Inligting

Watter effek het oligosakkariede, soos dié wat in peulgewasse voorkom, op die samestelling van dermflora by mense en indien wel, hoe so?

Watter effek het oligosakkariede, soos dié wat in peulgewasse voorkom, op die samestelling van dermflora by mense en indien wel, hoe so?


We are searching data for your request:

Forums and discussions:
Manuals and reference books:
Data from registers:
Wait the end of the search in all databases.
Upon completion, a link will appear to access the found materials.

Ek weet dat dermflora wat oligosakkariede metaboliseer, soos dié wat in peulplante voorkom, die oorsaak is vir die bekende feit dat peulgewasse winderigheid veroorsaak, maar verander 'n oligosakkariedryke derm die samestelling (maw watter spesifieke bakterieë dit uitmaak) van dermflora in mense?


Die antwoord hierop is redelik kompleks, en dit hang af of jy van korttermyn- of langtermynveranderinge aan die mikrobiota praat.

As daar oor korttermynveranderinge gepraat word, is die antwoord byna seker 'n dawerende ja. Enige ingeneemde voedingstof sal lei tot 'n toename in die groeitempo van bakterieë wat in staat is om daardie voedingstof te metaboliseer, en sal dus lei tot 'n verandering in die samestelling van die dermmikrobiota.

Dit is ongelukkig moeilik om waar te neem, aangesien die meeste studies van die dermmikrobiota fekale monsters gebruik om na dermmikrobiese samestelling te kyk. Aangesien stoelgang 'n gemiddelde verteenwoordig van wat tussen twee dermbewegings gebeur, is dit moeilik om afleidings te maak oor korttermynveranderinge in die mikrobiese samestelling van die derm. Daar is egter bewyse van Pythons wat daarop dui dat uitgebreide hermodellering van die mikrobiese samestelling wel plaasvind, ten minste in diere met minder gereelde voedingsskedules.

In die geval van langtermynveranderinge is daar sterk bewyse dat spesifieke oligosakkariede wat in menslike melk vervat is, spesifiek vir sekere stamme van Bifidobakterie en Lactobacillus. Afgesien van hierdie baie spesifieke stel oligosakkariede, is daar egter min studies wat handel oor die uitwerking van dieet op die dermmikrobiota, en selfs minder kyk na spesifieke voedingstowwe.

Die uitgangspunt dat langtermynveranderinge aan die dermmikrobiota met diëte gemaak kan word, is die grondslag waarop die hele prebiotikabedryf gebou is. Die gewildste prebiotika is frukto-oligosakkaried, inulien, galakto-oligosakkaried en laktulose. Daar word gesê dat dit die groei van voordelige stamme van aanmoedig Bifidobakterie en Lactobacillus. Daar is egter tans geen konsensus oor die langtermyn-effekte van hierdie oligosakkariede op die mikrobiota nie.


Hoofstuk 8 - Prebiotika in babaformules: risiko's en voordele

Hierdie hoofstuk bespreek die sterkte van bewyse rakende die immuunstimulerende effekte van prebiotika, en hoe dit in huidige babaformules gebruik word. Dit hersien die risiko's verbonde aan die gebruik daarvan en wat die regulatoriese status van prebiotika in babaformules is. Prebiotika in vroeë voeding het diepgaande uitwerking op die dermversperring, interne milieu en verdedigingsmeganismes. Dit is goed vasgestel dat 'n prebiotiese mengsel in babaformule 'n bifidogene effek het. Gebaseer op eksperimentele data, is daar bewyse dat prebiotiese oligosakkariede die natuurlike verdedigingstelsel teen infeksie tydens kinderskoene kan moduleer. Dit word gedemonstreer dat 'n mengsel van frukto-oligosakkariede en galakto-oligosakkariede wat by 'n babaformule (0,88 g/dL) gevoeg word, die aantal bifidobakterieë in ontlasting aansienlik verhoog op 'n dosisverwante manier en die aantal patogene verminder in vergelyking met onaangevulde formule. . Die funksionele effekte van prebiotika op baba gesondheid en die langtermyn effekte van verskillende dieet prebiotika op volwasse gesondheid en gastroïntestinale siektes moet verder bestudeer word in gekontroleerde intervensie proewe.


Opsomming

Prebiotika is bekend vir hul gesondheidsvoordele vir die mens, insluitend die vermindering van kardiovaskulêre siektes en die verbetering van dermgesondheid. Hierdie oorsig neem 'n kritiese beoordeling van die impak van dieetvesels en prebiotika op die gastroïntestinale mikrobiota in vitro. Die rolle van kolonorganismes, stadige fermentasie van prebiotika, produksie van hoë botter- en propionsure en positiewe modulasie van die gasheergesondheid is in ag geneem. Ook die kortkettingvetsure (SCFA's) molekulêre seinmeganismes wat verband hou met hul prebiotiese substraat strukturele konformasies en die fenotipiese response wat verband hou met die dermmikrobes samestelling is bespreek. Verder is algemene dieetvesels soos weerstandbiedende stysel, pektien, hemisellulose, β-glukan en fruktaan in konteks van hul prebiotiese potensiaal vir menslike gesondheid ook verduidelik. Ten slotte, die in vitro menslike kolonfermentasie hang af van prebiotiese tipe en sy fisies-chemiese eienskappe, wat dan die fermentasietempo, selektiwiteit van mikro-organismes om te vermenigvuldig, en SCFAs konsentrasies en samestellings sal beïnvloed.


OPSOMMING EN GEVOLGTREKKINGS

Peulgewasse was tradisioneel 'n belangrike deel van die dieet van baie kulture regoor die wêreld. Daarteenoor, in ontwikkelde lande speel boontjies tans slegs 'n geringe dieetrol. Die voedingsprofiel van bone toon dat hulle baie het om te bied bone is hoog in proteïen, laag in versadigde vet, en hoog in komplekse koolhidrate en vesel. Bone is ook 'n goeie bron van verskeie mikrovoedingstowwe en fitochemikalieë. Sojabone is uniek onder die peulgewasse omdat dit 'n gekonsentreerde bron van isoflavone is. Daar is veronderstel dat isoflavone die risiko van kanker, hartsiektes en osteoporose verminder, en ook help om menopousale simptome te verlig. Alhoewel daar baie is om te leer oor die uitwerking van isoflavone op die risiko van chroniese siektes, hou hierdie navorsingsgebied aansienlike potensiaal in. Gegewe die voedingstofprofiel en fitochemiese bydrae van peulgewasse, behoort voedingkundiges 'n daadwerklike poging aan te wend om die publiek aan te moedig om meer bone in die algemeen en meer sojakos in die besonder te verbruik.


Kos met FODMAPS

Watter oligosakkariede is FODMAPs?

Het jy al ooit opgeblasenheid of winderigheid opgemerk nadat jy 'n bak boontjies geëet het? Verhoogde opgeblasenheid na die eet van peulgewasse is as gevolg van die _oligosakkaried _inhoud.

Oligosakkariede is koolhidraatkettings wat bestaan ​​uit drie tot nege eenvoudige suikers wat monosakkariede genoem word.

  • Groente wat FODMAP's bevat, sluit in artisjokke, broccoli, ertjies, vinkel, knoffel, kool, prei, Brusselse spruite, rucola, aspersies en uie.
  • Korrels wat FODMAPs bevat, sluit rog en koring in.
  • Vrugte wat FODMAP's bevat, sluit in persimmons, witperskes, appels en waatlemoene.
  • Peulgewasse wat FODMAPS bevat, sluit in rooi en wit boontjies, kekerertjies en lensies. Die winderigheid wat dikwels volg op 'n maaltyd ryk aan boontjies word geproduseer deur die effek van FODMAPs op gasproduksie en fermentasieprosesse tydens vertering, omdat peulgewasse besonder ryk aan oligosakkariede is.

Watter disakkariede is FODMAPs?

Disakkariede is dubbele suikers. Melksuiker, genaamd laktose, is die disakkaried in FODMAP. Laktose word deur die ensiem afgebreek laktase in die dermslymvlies, en dan geabsorbeer. As daar nie genoeg laktase is nie, is daar tipiese simptome van FODMAP-intoleransie soos gas, opgeblasenheid en buikpyn.

Daar word nou geglo dat daar verskillende vlakke van laktose-intoleransie is. Benewens mense wat laktose verdra en mense wat nie laktose verdra nie, kan dit moontlik wees om intermediêre vlakke van laktose-intoleransie te hê. Laktoseverdraagsaamheid verander na gelang van lewenstyl en ouderdom.

Terwyl byna alle babas laktose verdra, is die meerderheid volwassenes wêreldwyd laktose-onverdraagsaam. Dit sal ook verduidelik waarom FODMAP-verdraagsaamheid in sommige gevalle deur die lewe versleg.

Watter monosakkariede is FODMAPs?

Monosakkariede is eenvoudige suikers. Onder eenvoudige suikers is fruktose een van die FODMAPs.

Fruktose word as 'n versoeter in koeldrank en baie ander kosse gebruik. In die afgelope paar jaar het mieliesiroop, ook genoem hoë-fruktose mieliesiroop, of HFCS, die verbruik van fruktose aansienlik verhoog.

Fruktose is 'n FODMAP wat gevind word in:

  • appels
  • pere
  • waatlemoene
  • mango's
  • ingemaakte en gedroogde vrugte
  • heuning
  • gaskoeldrank
  • voedsel wat mieliesiroop bevat (ook genoem hoë-fruktose mieliesiroop, of HFCS)

In alle mense, selfs diegene sonder prikkelbare derm-sindroom of fruktose-intoleransie, is die kapasiteit om te absorbeer beperk omdat die menslike spysverteringstelsel ontwerp is om slegs klein hoeveelhede vrugte in te neem, en nie die groot hoeveelhede suiker wat baie diëte vandag insluit nie.

As te veel fruktose gelyktydig ingeneem word, bly van die FODMAP's in die ingewande en die tipiese simptome van FODMAP-intoleransie kom voor. Sommige navorsing het aangedui dat 80 persent van mense wat 50 gram of meer fruktose per dag eet, dit nie goed opneem nie.

Watter bloliole is FODMAPS? En hoekom veroorsaak suikervervangers diarree?

Poliole is suikeralkohole, waarvan die bekende verteenwoordigers is sorbitol, mannitol, xylitol, en maltitol.

Poliole word in sommige soorte vrugte en groente aangetref:

As kinders aan te veel kersies peusel en nie goed voel nie, is dit die gevolg van die bakteriële fermentasie van die FODMAPs wat in kersies vervat is.

Poliole word ook dikwels as suikervervangers in lae-kalorie kosse gebruik. Poliole word ook bygevoeg in suikervrye lekkers en kougom om die tande te beskerm teen holte-veroorsakende sukrose.

FODMAPs is osmoties effektief. Dit beteken dat hulle vloeistof bind of selfs uit die ingewande in die stoel trek. Dit kan lei tot diarree met hoë inname. Aangesien hulle swak deur die dermwand geabsorbeer word en water aantrek, maak hulle die stoelgang vloeibaar.

Die Verenigde State se Food & # x26 Drug Administration (FDA) etiketteer sekere polyol FODMAPs as voedselbymiddels met spesifieke vereistes. Hierdie FODMAPS word as versoeters gebruik en moet die volgende stelling op die etiket van die voedselproduk hê: "Oormatige verbruik kan 'n lakseermiddel hê."


Voedingswaarde

Dieetvesel eienskappe

Volgens EU-Kommissierichtlijn EC/2008/100 (Europese Kommissie 2008), sluit dieetvesel 'n wye verskeidenheid onverteerbare koolhidrate in met 'n DP van 3 of meer (plus lignien). Hierdie verbindings is tradisioneel afkomstig van plantmateriaal, insluitend vrugte, graan, peulgewasse, sade, neute, peulgewasse. Die hooftipes dieetvesel is nie-stysel-polisakkariede (sellulose, hemisellulose, pektiene, tandvleis, mucilages en beta-glukane), weerstandbiedende oligosakkariede (inulien, oligofruktose, FOS, galakto-oligosakkariede), weerstandbiedende stysel en lignien (geassosieer met polisakkariede) ). Gemiddelde dieetveselinname by volwassenes in Europese lande wissel tussen 15 en 30 g/d (European Food Safety Authority 2010). Hierdie vlak van inname is laer as 3,4 g/MJ (14 g per 1000 kcal), soos aanbeveel deur amptelike liggame (Instituut of Medicine of the National Academies 2001 Health Council of the Netherlands 2006 ). Dieetvesel kan direkte uitwerking op die ingewande en/of die mikrobiota hê. Dit kan ook indirekte effekte hê wat bemiddel word deur veranderinge in die samestelling en/of metaboliese aktiwiteite van die mikrobiota. Die Gesondheidsraad van Nederland (2006) het die gesondheidsvoordele van dieetvesel geëvalueer, bloot op grond van voedselverbruikdata en gesondheidsuitkomste, en het tot die gevolgtrekking gekom dat dieetvesel deurvoertyd verminder en hardlywigheid verminder 'n hoëveseldieet (veral volgraan en vrugte) verminder die risiko van koronêre hartsiekte en kan help om oorgewig te voorkom. As gevolg van die molekulêre heterogeniteit, vertoon verskillende tipes dieetvesel nie identiese fisiologiese effekte nie en daarom moet effekte van die inname van inulien en oligofruktose spesifiek in ag geneem word. Hulle kan onderskei word in intestinale en sistemiese effekte (Figuur 1).

Veiligheid, verdraagsaamheid en kaloriewaarde

Oor die algemeen is daar geen veiligheidskwessies met die inname van onverteerbare oligosakkariede nie, maar oormatige inname kan ongewenste newe-effekte veroorsaak, soos winderigheid, opgeblasenheid, gedreun, krampe en vloeibare stoelgang, wat veroorsaak word deur gasvorming en osmotiese effekte van sekere fermentasieprodukte. Dit is kortkettingvetsure (SCFA) en laktaat en hulle word in die blindedarm en kolon gevorm. Verspreiding van die inname oor die dag en inname met vaste kos (maaltye), sowel as aanpassing van 'n ongewenste dermflora, kan sulke newe-effekte verminder, alhoewel interindividuele variasie in reaksie bestaan ​​(Marteau en Florié 2001). Newe-effekte sal minder wees met langketting-inulinemolekules, aangesien dit gefermenteer word teen 'n tempo wat ongeveer 50% laer is as dié van kortketting-inulinemolekules (Roberfroid en andere 1998 Coussement 1999). Havenaar (2000) het studies in mense hersien en tot die gevolgtrekking gekom dat by volwassenes tot 20 g/d inulien met 'n gemiddelde DP van 9 nie ernstige nadelige newe-effekte veroorsaak nie, behalwe ligte tot matige ongemak soos winderigheid by sommige individue. In die groot meerderheid studies oor die voedingswaarde van oligofruktose en inulien was innamevlakke onder 20 g/d. In 2 onlangse gerandomiseerde beheerde proewe (RCT's Bonnema en ander 2010 Holscher en ander 2014), is die verdraagsaamheid van matige dosisse (5 tot 10 g/d) sigorei-oligofruktose, sigorei-inulien en agave-inuline bevestig. Slegs ligte gastroïntestinale newe-effekte (winderigheid en opgeblasenheid) is waargeneem en hierdie effekte was minder met inheemse inulien as met oligofruktose. As dit nie in oormaat gegee word nie (meer as 80 g/d sien Clausen en ander 1998), word inulien heeltemal gefermenteer in die kolon, wat lei tot die produksie van SCFA (hoofsaaklik asynsuur, propionzuur, bottersuur) en laktaat.

Op grond van biochemiese balanskaarte vir koolstofatome, metaboliese weë en energie-opbrengs aan die gasheer, het Roberfroid (1999) vir inulien 'n kaloriewaarde van 25% tot 35% van dié van volledig verteerde en geabsorbeerde fruktose bereken. Soortgelyk as vir ander onverteerbare koolhidrate wat min of meer heeltemal deur die dermflora gefermenteer word, het Roberfroid (1999) 'n energiewaarde van 1,5 kcal/g vir inulien en oligofruktose vir voedseletiketteringsdoeleindes voorgestel. Die Europese Unie het in 2008 'n energiewaarde van 2 kcal/g vir alle dieetvesels aangeneem (Europese Kommissie 2008 European Food Safety Authority 2010 ). Ook Health Canada (2012) het hierdie waarde aangeneem en in die onlangs voorgestelde reëls om voedingsinligting aan te pas, het die Amerikaanse FDA hierdie waarde voorgestel (Food and Drug Administration 2014).

Mondgesondheid

Inulien en oligofruktose word nie deur speekselensieme afgebreek nie, maar kan deur die orale streptokokke gefermenteer word. In reaksie op die inname van oligofruktose of inulien word fruktanases geïnduseer en suur word gevorm. Dit is deur Hartemink en andere (1995) gevind dat oligofruktose gefermenteer word deur Streptococcus mutans en vorm plae teen 'n tempo wat vergelykbaar is met dié van sukrose, wat aandui dat oligofruktose so kariogeen soos sukrose kan wees. Aangesien inulien of oligofruktose in baie gevalle op dieselfde tyd as glukose of sukrose in die mondholte teenwoordig sal wees en aangesien fermentasie van inulien en oligofruktose onderhewig is aan katabolietonderdrukking, is kariogeniese effekte waarskynlik relatief klein. Doran en Verran (2007) het die moontlikheid ondersoek dat inulien, deur stimulering van orale asidogeniese mikroörganismes, orale wanreuk kan verminder, en tot die gevolgtrekking gekom dat sukrose en inulien vergelykbare effekte het in die vermindering van die tong pH.

Samestelling van die derm mikrobiota

Die aantal mikrobiese selle in die ingewande is ongeveer 10 14 en oortref die liggaamselle met 'n faktor van 10. Meer as 1000 verskillende spesies word wêreldwyd erken met honderde in 1 individu (Rijkers 2014). Die mikrobiota kan beskou word as 'n ekosisteem wat kolonisasieweerstand teen patogene bied en wat intensief met die gasheer in wisselwerking tree, deur beide die aangebore en aanpasbare immuunresponse te moduleer en deur metaboliete te produseer wat die liggaam beïnvloed. Die samestelling en metaboliese aktiwiteite van die mikrobiota word beïnvloed deur genetiese gasheerfaktore en deur eksterne invloede, insluitend dieetsamestelling en inname van geneesmiddels, veral antibiotika. Die dermmikrobiota het 'n indrukwekkende impak op menslike gesondheid. Navorsing van die afgelope dekade het getoon dat veranderinge in die mikrobiese samestelling geassosieer word met spesifieke siektes, insluitend allergieë, coeliakie, vetsug, anoreksie, inflammatoriese dermsiekte en tipe 2-diabetes (Clemente en ander 2012).

Saam met trans-galakto-oligosakkariede, is inulien en oligofruktose "selektief gefermenteerde bestanddele wat spesifieke veranderinge toelaat, beide in die samestelling en/of aktiwiteit in die gastroïntestinale mikrobiota wat voordele verleen aan gasheerwelstand en gesondheid" daarom word dit prebiotika genoem. (Roberfroid 2007). Dit is goed gevestig deur in vitro studies, in diere-eksperimente en studies in mense, insluitend formule-gevoede babas, dat inulien en oligofruktose die groei van bifidobakterieë stimuleer (Roberfroid 2007 Meyer en Stasse-Wolthuis 2009 Roberfroid en andere 2010). Bifidobakterieë oorheers die dermflora in borsvoedende babas en vorm een ​​van die belangrikste organismes in die kolonflora van gesonde kinders en volwassenes. Bifidobakterieë word beskou as 'n belangrike rol in die handhawing van 'n gesonde en stabiele mikrobiese ekosisteem. Hul getalle is oor die algemeen laag in verskeie siektetoestande en hul vermindering of verdwyning uit die menslike ingewande sou 'n "ongesonde" toestand aandui (Mitsuoka 1990). Gibson en Wang (1994a) het getoon dat Bifidobakterieë, benewens die produksie van asynsuur en melksuur, 'n antimikrobiese stof met 'n breë spektrum van aktiwiteit teen patogene bakterieë uitskei. Meer onlangs is dit in beide gedemonstreer in vitro en diere-eksperimente, wat duidelike stamme van bifidobakterieë beïnvloed rypwording- en sitokienproduksiepatrone van dendritiese selle van die dermslymvlies (Menard en ander 2008 Dong en ander 2010 Lopez en ander 2011). Dendritiese selle monster antigene uit voedsel en bakterieë en moduleer die immuunstelsel. Deur afskeiding van sitokiene beheer hulle B- en T-limfosiete, wat gevolge kan hê vir die ontwikkeling van verdraagsaamheid en inflammasie. Onlangse inligting van in vitro proewe dui daarop dat inulien en oligofruktose ook direk met die immuunstelsel kan interaksie hê deur die Tol-agtige Reseptor 2, wat selaktivering bemiddel (Vogt en ander 2013, 2014). Bifidobakterieë is nie die enigste spesie wat deur oligofruktose of inulien gestimuleer word nie. Ook butyraat-produserende Faecalibacterium prausnitzii en Eubakterie spp. toename in reaksie op inulien- of oligofruktose-inname (Ramirez-Farias en ander 2009 Louis en ander 2010).

Metaboliese aktiwiteite van die dermmikrobiota

Uit resensies deur Cummings en Macfarlane (1997), Macfarlane en Macfarlane (1997, 2011) en van Loo en andere (1999) word die metaboliese aktiwiteite van die dermflora in die dikderm soos volg opgesom. Die aktiwiteite van die anaërobiese mikroörganismes kan gerieflik gedifferensieer word in sakkarolitiese- en proteolitiese aktiwiteite, waardeur die 1ste hoofsaaklik in die proksimale derm en laasgenoemde hoofsaaklik in die distale derm voorkom. Die metaboliese potensiaal van die kolonmikrobiota is vergelykbaar met dié van die lewer in aantal biochemiese reaksies en transformasies.

Die totale hoeveelheid fermenteerbare koolhidrate in die westerse dieet wat uit die ileum gelewer word, is op 30 tot 40 g/d geraam. Kekale en kolonkoolhidraatfermentasie lei tot die produksie van SCFA, laktaat, gasse (waterstof, koolstofdioksied en metaan) en tot 'n verlaging van die luminale pH. Die SCFA word grootliks (95% tot 99%) geabsorbeer, wat ongeveer 10% van die menslike energiebehoefte dek. Butiraat word direk deur die kolonselle gebruik, wat 'n trofiese effek op hierdie selle uitoefen. SCFA stimuleer sout- en waterabsorpsie en epiteelgroei. Die sakkarolitiese aktiwiteite verhoog biomassa, fekale massa, stoelgewig en stoelfrekwensie. Vir inulien is die toename in stoelgewig by volwassenes relatief klein (1,5 tot 2 g per g ingeneemde inulien). In vitro fermentasie van inulien-tipe fruktane met menslike sekale of fekale mikrobiota dui op 'n tipiese toename in die produksie van asetaat en butiraat. Sedert Bifidobakterieë produseer nie butyraat, dit dui daarop dat ander bakterieë as net Bifidobakterieë ook voordeel trek uit hierdie substraat of dat kruisvoeding kan voorkom (Belenguer en andere 2006).

In vitro fermentasie van oligofruktose het getoon dat 40 mol% SCFA is, 15% laktaat is, 5% koolstofdioksied, en 40% van die C-atome gebruik mag word vir biomassa sintese (Havenaar en Petitet 1996). Volgens Morrison en andere (2006) produseer bifidobakterieë en laktobacilli asetaat en laktaat uit oligofruktose. Vervolgens word ekstrasellulêre asetaat omgeskakel na butiraat en ekstrasellulêre laktaat na asetaat, propionaat en butiraat met 'n groot rol vir butiraat-produserende bakterieë wat verband hou met F. prausnitzii en Roseburia spp. (Duncan en andere 2004).

Die ileale lewering van proteïen by volwassenes is geskat op 12 tot 18 g/d en is afgelei van onverteerde dieetproteïene en endogene verteringsensieme. Die stikstof word gedeeltelik vir mikrobiese biomassa sintese gebruik. Die res van die proteïen word gefermenteer. Dit lei tot 'n verskeidenheid produkte, insluitend vertaktekettingvetsure (BCFA van die vertaktekettingaminosure valien, leusien en isoleusien), in ammoniak (vanaf deaminering van aminosure), in indole en fenole (van aromatiese aminosure ), en in amiene (vanaf dekarboksilering van aminosure). Sulfiede word uit sulfaat gevorm deur sulfaatverminderende bakterieë. Die omvang van proteïenfermentasie hang af van 'n aantal faktore, insluitend deurgangstyd, die hoeveelheid proteïen in die kolon en die hoeveelheid proteïen wat vir biomassasintese gebruik word. Ammoniak, sulfiede, indool en fenole word as giftig vir die dikderm-epiteel beskou. Van Nuenen en andere (2003) het in 'n kolonmodel met 'n menslike flora gedemonstreer dat inulien die vorming van ammoniak, fenoliese verbindings en BCFA inhibeer, wat daarop dui dat stimulering van sakkarolitiese aktiwiteite en biomassaproduksie proteïenfermentasie verminder het. Swanson en ander (2002) het in 'n proef met mense getoon dat 'n klein hoeveelheid FOS (3 g/d vir 4 wk) fekale proteïenammoniak (P < 0.07) en isovaleriaat (P < 0.11). De Preter en andere (2008) het getoon dat beide laktulose en oligofruktose-verrykte inulien in 'n dosis van 10 g/d vir 4 wk die urinêre uitskeiding van parakresol en kolonammoniak vorming aansienlik verminder het.

Regulerende en epigenetiese effekte van butyraat

Onlangse studies het aangedui dat, behalwe dat dit 'n energiebron is, SCFA en veral butyraat 'n reeks voordelige effekte kan uitoefen, beide op die derm- en ekstra-intestinale vlakke deur op leukosiete, dermselle en endoteelselle in te werk deur inhibisie van histoon-deasetilase ( Gao en ander 2009 Canani en ander 2011, 2012) en metaboliese regulering deur sein deur guanosiennukleotiedbindende proteïene (G-proteïene), wat geaktiveer word deur proteïengekoppelde reseptore (GPCR's), soos GPR41 of GPR43 (Vinolo en ander 2011) ). G-proteïene reguleer metaboliese ensieme en ioonkanale, en beheer selfunksies soos transkripsie, beweeglikheid, kontraktiliteit en afskeiding. Hulle dien as molekulêre skakelaars. Histoon-deasetilases reguleer geentranskripsie deur modifikasie van chromatienstruktuur deur deasetilering van proteïene, insluitend histoonproteïene en transkripsiefaktore. Dit is getoon dat natriumbutyraat peroksisoomproliferator-geaktiveerde reseptor gamma-koaktivator 1 (PGC-1)-aktiwiteit in skeletspiere en bruinvet in muise induseer (Gao en andere 2009). PGC-1 is 'n transkripsie-koaktiveerder van PPAR-y (peroksisoomproliferator-geaktiveerde reseptor).

Die epigenetiese effekte van butiraat op leukosiete lei tot veranderinge in die produksie van sitokiene en chemokiene en kan lei tot anti-inflammatoriese effekte, bevordering van selgroei en differensiasie, versterking van die intestinale versperring funksie, verbetering van intestinale motiliteit, inhibisie van intestinale cholesterol sintese , vermindering van vetsug deur mitochondriale funksie te verbeter, en verhoging van insuliensensitiwiteit in tipe 2-diabetes (Canani en ander 2012 Tremaroli en Bäckhed 2012). Die anti-inflammatoriese effek van butiraat hou waarskynlik verband met die versterking van die dermversperring teen die vervoer van lipopolisakkariede (LPS'e) en peptidoglikaan vanaf die lisis van Gram-negatiewe bakterieë). Dit is bekend dat hierdie verbindings die produksie van pro-inflammatoriese sitokiene veroorsaak en sistemiese inflammasie veroorsaak. Orale toediening van butyraat is gerapporteer om die produksie van makrofaag chemoattractant proteïen (MCP-1) in vetweefsel te verminder MCP-1 is betrokke by die werwing van makrofage in vetweefsel en is relevant vir die ontwikkeling van insulienweerstand deur inflammatoriese bemiddelaars, geproduseer deur geaktiveerde makrofage, in vetsugtige vakke (Vinolo en ander 2011).

Derm gewoonte

Die toename in sakkarolitiese aktiwiteite van die dermflora, in reaksie op die inname van oligofruktose of inulien, verhoog biomassa, fekale massa, stoel frekwensie, en lei tot sagter stoelgang en word dus geassosieer met 'n anti-hardlywigheid effek of ligte lakseermiddel effek, sonder om transito te beïnvloed. tyd. Die effek van heeltemal fermenteerbare vesels, soos inulien en FOS, op fekale massa is bekend om minder te wees as dié van vesels met sterk waterhouvermoë wat grootliks ongeskonde die blindedarm bereik, soos koringvesel (FAO 1998). Den Hond en ander (2000) het verhoogde stoelfrekwensie en verhoogde fekale massa (1,5 g per 2 g ingeneemde inulien) waargeneem by proefpersone met 'n lae stoelfrekwensiepatroon, wat vir 2 weke 15 g inulien per dag ingeneem het (gemiddelde DP van 25) . 'n Anti-hardlywigheid-effek in gekontroleerde studies by proefpersone met lae stoelgangfrekwensie is ook gerapporteer vir FOS (3 g/d: Tominaga en ander 1999) en vir inulien (12 tot 20 g/d: Kleessen en ander 1997 Tomono en ander 2010 Marteau en ander 2010). Sulke data toon duidelik die dieetveselkenmerke van inulientipe fruktane. Onlangs het Dahl en ander (2014) die dieetvesel-eienskap op stoelfrekwensie van oligofruktose in 'n RCT met 'n parallelle ontwerp bevestig. Vyf-en-negentig gesonde jong volwasse vrywilligers met gewone veselinnames onder 20 g/d (gemiddeld: 12.1 g/d) het daagliks, as deel van hul dieet, 16 g oligofruktose via 2 versnaperinge vir 8 wk ingeneem. Dit het hul gemiddelde veselinname van 12,1 tot 24,3 g/d verhoog. Oligofruktose het die gemiddelde stoelfrekwensie van onderskeidelik 1,3 tot 1,8 en van 1,0 tot 1,4 ontlasting per dag by mans en wyfies verhoog. Simptome van intestinale ongemak, veral winderigheid, het matig gebly, behalwe vir 'n paar proefpersone op 'n paar dae, met geen aanpassing oor tyd nie. Slegs 1 proefpersoon het genoeg ongemak ervaar om die studie te stop.

Kolonisasie weerstand teen patogene

In vitro eksperimente, dierestudies en menslike studies het getoon dat die bifidogene effekte van oligofruktose en inulien dikwels geassosieer word met onderdrukking van groei van (potensieel) patogeniese organismes, soos bv. Enterobacteriacae, E. coli, Clostridium perfringens, Salmonella, Listeria, Campylobacter, Shigella, Vibrio cholera (Wang en Gibson 1993 Gibson en Wang 1994b Gibson en ander 1995 Catala en ander 1999 Fooks en Gibson 2002). Sulke voordelige veranderinge in die mikrobiota is egter nie altyd waargeneem nie. Dus, in studies met mense, het Tuohy en ander (2001a, 2001b) waargeneem dat die bifidogene effek van 'n hoë-molekulêre-gewig fraksie van inulien geassosieer word met 'n klein toename in Clostridium en dat die bifidogene effek van oligofruktose nie gelei het tot die verandering van die getalle van Clostridium en Enterokokkus. Relatief klein hoeveelhede FOS in die dieet van hoenders (0,375 of 0,75%) verminder vatbaarheid vir Salmonella kolonisasie (Bailey en andere 1991), maar in rotte het 6% van dieetoligofruktose of inulien wel die kolonisasie van Salmonella in kekale inhoud, maar het die translokasie van verbeter Salmonella na 'n uitdaging met hierdie patogeen is die effek gedeeltelik voorkom deur die kalsiuminhoud van die dieet te verhoog (Bovee-Oudenhoven en andere 2003 Ten Bruggencate en andere 2004). Daar is aangedui dat die suur wat deur fermentasie gevorm word, irritasie van die onderste dermwand verhoog en sy versperringsfunksie verminder het. Toenemende dieetkalsium het tot groter hoeveelhede kalsiumfosfaat in die laer derm gelei en dit sou versuring van die derm-inhoud teengewerk het. Dit is moontlik dat verskille in dosis, agtergronddieet en metodologie van meting van die flora tot die variasie van respons bygedra het. Voordelige veranderinge in die samestelling van die dermflora en/of verhoogde kolonisasieweerstand teen patogene in reaksie op die bifidogene effekte van oligofruktose en inulien kan verklaar word deur direkte antagonisme (asetaat- en laktaatproduksie), kompetisie vir voedingstowwe en adhesieplekke, en stimulasie van immuniteit (Fuller en Gibson 1997 Corr en andere 2007 Fukuda en ander 2011).

Mineraalabsorpsie, beengesondheid en vitamiensintese

Uitgebreide navorsing in diere, hoofsaaklik rotte, het konsekwent getoon dat onverteerbare koolhidrate wat deur die dermflora gefermenteer word, insluitend oligofruktose en inulien, toegedien in dosisse van 25 tot 150 g/kg dieet, die absorpsie van minerale in die kekale en kolon verhoog, veral kalsium. en magnesium hierdie effek word geassosieer met toenames in kortikale beenmassa in groeiende rotte en voorkom beenverlies in ovrieektomized diere (van den Heuvel en Weidauer 1999 Scholz-Ahrens en andere 2007). Die effek is afhanklik van bakteriële fermentasie, aangesien dit nie by kiemvrye diere aangetoon kan word nie. Die geïmpliseerde meganisme hou waarskynlik verband met die vorming van SCFA, vermindering van die luminale pH, verbeterde mineraaloplosbaarheid en verhoogde parasellulêre vervoer, gemedieer deur osmotiese effekte en verhoogde luminale vloeistofvolume, wat die intersellulêre stywe aansluitings losmaak (van den Heuvel en Weidauer 1999). ). Nog 'n moontlikheid is dat die trofiese effekte van SCFA op kekale en kolonepiteel die absorpsiekapasiteit van die mukosa verhoog.

Resultate van studies in mense oor mineraalabsorpsie is minder konsekwent. Tabel 2 som die studies op oor die effek van prebiotika op kalsiumabsorpsie. Deur die klassieke balanstegniek te gebruik, het Coudray en andere (1997) getoon dat dosisse inulien tot 40 g/d die oënskynlike absorpsie en retensie van Ca verhoog het, maar nie dié van Mg, Zn of Fe by jong gesonde mans nie. Maar van den Heuvel en andere (1998), wat 'n stabiele isotooptegniek gebruik, het nie 'n positiewe effek op ware fraksionele absorpsie van Ca en Fe gevind by jong gesonde mans wat 15 g/d inulien, oligofruktose of galakto-oligosachariede ingeneem het nie. Aan die ander kant het dieselfde groep 'n positiewe dosisverwante effek op ware fraksionele kalsiumabsorpsie in postmenopousale vroue van 10 g/d laktulose (van den Heuvel en andere 1999a) en van 20 g/d trans-galakto-oligosakkariede waargeneem ( van den Heuvel en andere 2000). By manlike adolessente het 15 g/d oligofruktose ook kalsiumabsorpsie verhoog (van den Heuvel en andere 1999b). Griffin en ander (2002) het by meisies, wat rondom die menarge was, getoon dat 'n mengsel van oligofruktose en langketting-inulien teen 'n dosis van 8 g/d, maar nie van oligofruktose alleen nie, ware kalsiumabsorpsie verhoog het, terwyl Abrams en ander ( 2005b ) showed enhanced calcium absorption by a mixture of short- and long-chain inulin fructans, at a dose of 8 g/d. This resulted in a 35 g higher increment of the bone mineral content after 1 y. Using the classical balance technique, Kim and others ( 2004 ) showed that inulin (8 g/d) improved calcium absorption in postmenopausal women. More recently, Martin and others ( 2010 ) in a stable isotope study, with girls 11- to 12-y-old, found no effect on either Ca absorption or retention after 3 wk of ingestion of 9 g short- and long-chain inulin. Tahiri and others ( 2001 ), also using a stable isotope technique, reported enhanced Mg absorption and urinary magnesium excretion in postmenopausal women, given a dose of 10 g FOS per day for 5 wk.

Skrywers Tegniek Target group Prebiotic type and dose Resultate
Coudray and others ( 1997 ) Classical balance Young healthy men Inulin, 40 g/d, 4 wk Positive
Van den Heuvel and others ( 1998 ) Stable isotopes Young healthy men Inulin, oligofructose or galacto-oligosaccharides, 15 g/d, 3 wk Not significant
Van den Heuvel and others ( 1999a ) Stable isotopes Postmenopausal women Lactulose, 10 g/d, 9 d Positive
Van den Heuvel and others ( 1999b ) Stable isotopes Male adolescents Oligofructose, 15 g/d, 9 d Positive
Van den Heuvel and others ( 2000 ) Stable isotopes Postmenopausal women Galacto-oligosaccharides, 20 g/d, 9 d Positive
Griffin and others ( 2002 ) Stable isotopes Young girls Oligfructose/inulin mixture, 8 g/d, 3 wk Positive
Griffin and others ( 2002 ) Stable isotopes Young girls Oligofructose, 8 g/d, 3 wk Not significant
Abrams and others 2005b Stable isotopes Adolescents Mixture of short- and long-chain inulin , 8 g/d, 1 y Positive
Kim and others ( 2004 ) Classical balance Postmenopausal women Inulin 8 g/d, 3 mo Positive
Martin and others ( 2010 ) Stable isotopes Young girls Mixture of short- and long-chain inulin, 9 g/d, 3 wk Not significant

The positive effects on mineral absorption in humans, although physiologically meaningful, are relatively small (about 10% increase of true fractional absorption) and therefore not easy to detect. This may explain in part the variability of results. Moreover, differences in physiological status, background diet, dose, and way of its administration may play a role. Based on data from their long-term trial in adolescents, Abrams and others ( 2005a ) have suggested that polymorphisms of the specific vitamin D receptor (Fok1) gene directly affect bone mineralization during pubertal growth through an effect on calcium absorption. The Fok1 effect on whole body bone mineral density (BMD) was only significant for those with high calcium intake. In a follow-up study, these investigators evaluated 32 responders and 16 nonresponders to the calcium absorptive benefit of inulin. It was found that responders who increased their calcium absorption by at least 3% after 8 wk of the 1/1 mixture of oligofructose and inulin, had a greater accretion of calcium to the skeleton over a year. There were no differences in habitual dietary calcium intakes between responders and nonresponders (Abrams and others 2007 ). So far, long-term effects on bone in postmenopausal women have not been assessed.

Baie Bifidobakterieë strains have the capacity to synthesize and excrete B-vitamins, including thiamine, folate, nicotinate, pyridoxine, and vitamin B12 (Ventura and others 2010 ). It is not known to what extent B-vitamins are absorbed in the cecum and colon and whether the bifidogenic effects of inulin fructans contribute to the vitamin B-status in humans. Santacruz and others ( 2010 ) showed that an increased level of bifidobacteria is associated with an improved folate status in pregnant women.

Intestinal hormones, satiety, and weight management

Studies in rats have shown that 10% dietary inulin-type fructans with different DPs decreases food intake and epididymal fat mass, apparently through increased production of SCFA and stimulated cecal and colonic secretion of the satiety hormones glucagon-like peptide-1 (GLP-1) and peptide YY (PYY) and a decrease in the serum orexigenic peptide ghrelin (Delzenne and others 2005 ). Oligofructose-enriched inulin supplementation in mice on a high-fat diet reduced weight gain, total body fat and liver fat contents, and these effects were associated with increases in fecal Bifidobakterieë, Lactobacillus, and SCFA. Functional magnetic resonance imaging (MRI) showed an increase in neuronal activation of the arcuate nucleus in the supplemented mice (Anastasovska and others 2012 ). Short-term studies in humans on the effect of oligofructose, however, have yielded inconsistent results. In a 2-wk study with humans, Cani and others ( 2006 ) found that 16 g oligofructose distributed over 2 meal replacement bars increased satiety and reduced food intake. In a carefully controlled crossover study with 31 young adults, Verhoef and others ( 2011 ) observed that ingestion of oligofructose (10 or 16 g for 13 d) tended to reduce food intake. With the higher dose, energy intake on day 13 was significantly lower (12%, P < 0.05) than with placebo, and this was associated with increased levels of GLP-1 (compared with the 10-g dose) and of PYY compared with the 10-g dose and placebo. In acute (1 to 2 d) experiments, no effects of inulin fructans were observed on appetite or food intake by Peters and others ( 2009 ) and Karalus and others ( 2012 ). Parnell and Reimer ( 2009 ), in a randomized placebo-controlled trial with 48 overweight adults, who consumed 21 g oligofructose per day for 12 wk, found no effects on subjective hunger and on GLP-1. But these subjects reported a lower energy intake, lost significantly more body weight, and had a lower ghrelin concentration and increased PYY levels. In this study, oligofructose supplementation improved blood-glucose control and this was associated with body fat loss, mainly from the trunk.

Evidence is accumulating (Rijkers and others 2012 Clemente and others 2012 Johnson and Olefsky 2013 ) that the interaction between environmental factors, the host, and its microbiome is involved in the development of such chronic diseases as obesity, type 2 diabetes, and metabolic syndrome. The interaction would involve the immune system with a central role for low-grade inflammation. In obese subjects, a relative abundance in the intestinal flora of Actinobacteriaceae en Firmicutes in vergelyking met Bakteroïede would result in an increased capacity to harvest energy from food and would produce moderate induction of inflammatory cytokines, increase in mast cells, T cells, and macrophages. An imbalance between Th1 and Th2 cells, caused by a disturbed microbiota would be responsible for allergies and autoimmune diseases. A low grade of inflammation is held responsible for insulin resistance. A more diverse microbiota would be related to health, while in disease conditions the diversity often seems to be decreased. An increase in bifidobacteria has also been shown to modulate inflammation in obese mice by increasing glucagon-like-peptide-2 (GLP-2), which reduces intestinal permeability and reduces translocation of bacterial LPS (Cani and others 2009 ).

Blood lipids and blood glucose regulation

Animal experiments, mainly in rodents, have consistently demonstrated that oligofructose and inulin in doses of 5 to 15 weight% of the diet lower blood triglyceride or cholesterol levels, most probably through inhibition of lipogenic enzymes in the liver following bacterial SCFA production (Delzenne and Kok 1999 ). Studies in humans have yielded variable results (Williams and Jackson 2002 Beylot 2005 ). In 2 well-controlled studies with normal subjects (Van Dokkum and others 1999 Pedersen and others 1997 ) and in 1 comparable study in patients with type 2 diabetes (Alles and others 1999 ), no significant effects were found on either blood triglyceride, blood cholesterol, or blood glucose regulation when with doses of oligofructose of 14 or 15 g/d for 3 or 4 wk . On the other hand, Causey and others ( 2000 ) observed a significant decrease of blood triglyceride levels after 3 wk of ingesting 20 g inulin daily and a trend to cholesterol reduction in hypercholesterolemic men.

The lipid-lowering effect of inulin fructans is probably related to the production of SCFA. The difference in response between rats and the men could be related to the lower doses used in studies with humans. On a body weight basis, these doses are about 40-fold higher in rats. Since oligofructose and inulin are not digested in the small intestine and are fermented in the large intestine, they do not contribute to the glycemic response after ingestion. In fact, this feature has now been recognized by the European Food Safety Authority as the basis for a health claim to reduce the postprandial glycemic response (European Food Safety Authority 2014 ).

Diseases of the gut and allergy

Several diseases of the colon are associated with changes in the composition and/or activity of microbiota. These are inflammatory bowel diseases (IBD, Crohn's disease, and ulcerative colitis), irritable bowel syndrome (IBS), and colon cancer. IBD is the result of an imbalance in the gut-associated lymphoid tissue, resulting in an increased Th1 T-cell-driven inflammatory response. An interaction between the mucosal immune system of the host and the microbiota is probably involved. Higher concentrations of Bacteroides and lower concentrations of Bifidobakterieë have been found in patients with Crohn's disease (Lindsay and others 2006 ). The immunomodulating effects of Bifidobakterieë may change the imbalance. In a pilot study with 10 patients having Crohn's disease, Lindsay and others ( 2006 ) found that the bifidogenic effect of 15 g of a mixture of oligofructose and inulin (7/3) daily for 3 wk was associated with reduced disease activity and functional changes of dendritic cells. However, in a much larger randomized controlled study with 103 patients, no reduction in the response to disease activity was found after 4 wk administering 15 g daily of a slightly different mixture (oligofructose/inulin, 1/1), although changes in dendritic cell function were noted (Ng and others 2011 ). In this study no (fecal) bifidogenic effect was seen (Benjamin and others 2011 ).

In rodent models of ulcerative colitis, several groups of investigators showed reduction of inflammation after administration of FOS, oligofructose, or inulin (Cherbut and others 2003 Winkler and others 2007 Koleva and others 2012 ). In a pilot RCT in colitis patients, Casellas and others ( 2007 ) reported that 12 g of oligofructose-enriched inulin reduced the fecal excretion of calprotectin, a marker of intestinal inflammation. Welters and others ( 2002 ) reported that supplementation of 24 g inulin per day for 3 wk in a randomized crossover study with 20 patients with an ileal pouch increased butyrate concentrations, lowered fecal pH and secondary bile acids, and decreased the number of Bacteroides fragilis in feces, while it reduced mucosal inflammation.

In rodent models of colon cancer, dietary FOS and inulin also showed favorable results on advanced stages of colon cancer development (Pierre and others 1997 ), and on the number of aberrant crypt foci, an early preneoplastic marker of malignant potential in colon cancer genesis (Reddy and others 1997 Hsu and others 2004 ). The proposed involved mechanisms are immunomodulation by the colonic microbial ecosystem and enhanced butyrate formation, associated with growth regulation and differentiation of colon cells (Bornet and Brouns 2002 ). In humans, no data are available on possible benefits of inulin fructans on colon cancer risk. Only 1 human study with inulin-based synbiotics showed favorable changes in biomarkers related to colon cancer (Rafter and others 2007 ). In another study (Bouhnik and others 1996 ), it was found that 12,5 g per day of FOS for 12 wk exerted a strong bifidogenic effect, but did not change the fecal parameters which are suspected to be involved in colon carcinogenesis, including nitroreductase, azoreductase, beta-glucuronidase, concentration of bile acids, and neutral sterols.

In IBS patients, a 2-fold decreased level of fecal bifidobacteria has been reported (Kerckhoffs and others 2009 ). From this, it might be expected that IBS symptoms could be reduced by supplementation with FOS or inulin. However, results of studies in IBS patients are not consistent. In a multicenter RCT, Olesen and Gudmand-Høyer ( 2000 ) found that 20 g/d of oligofructose for 12 wk had no significant effects on symptoms. But in another multicenter RCT (Paineau and others 2008 ), 5 g/d of FOS for 6 wk suggested improvement in digestive comfort, whereas in an earlier study 6 g/d of oligofructose had no therapeutic value (Hunter and others 1999 ).

A study in formula-fed infants showed that the bifidogenic effect of a mixture of galacto-oligosaccharides and long-chain inulin in the formula (0.8 g/100 mL) is associated with a significantly reduced incidence of atopic disease after 6-mo intervention in infants at risk of atopy (Moro and others 2006 ). After 2 y of a follow-up, cumulative incidences of atopic dermatitis, recurrent wheezing, and allergic urticaria were higher in the placebo group. This group also had more episodes of upper respiratory tract infections and antibiotic prescriptions. The benefits of the prebiotic mixture were attributed to its bifidogenic effect (Arslanoglu and others 2008 ). It is possible that changes in the intestinal flora modulate the immune system by bringing about a shift in the activity of Th-2 cells (predominant atopic activity) to Th-1 cells.


Effects of gut microbiota on nutrient utilization, growth, and health

The GIT is the ultimate organ for host digestion and immunity and the proper functioning of this organ gut microbiota should be in balance and dynamic state. Gut microbiota affects the metabolic processes directly such as Clostridium cluster XIV, and Ruminokok can break cellulose and resistant starch [54]. Indirectly as most of the bacteria phylotypes abundant in higher AME utilizing and higher growth performing birds are firmly related to bacteria with known beneficial metabolic characteristics [55]. Also, the most dominant cecal microbes Firmicutes, and Bacteroidetes are correlated with body weight as their ratio is found significantly higher in obese hosts and lower in hosts of low to healthy body weight [56]. For proper intestinal function and integrity, bacterial fermentation plays an essential role by producing fermentation by-products such as SCFAs, especially butyrate, to provide energy to the epithelial cells and another SCFAs undergoes diffusion to enter different metabolic pathways. Other functions of SCFAs include regulation of intestinal blood flow, mucin production, enterocyte growth and proliferation, and intestinal immune responses [57]. Lactobacillus sp. is known to produce a variety of SCFAs and bacteriocins with bacteriostatic or bactericidal properties either by reducing pH or by modifying the receptors against pathogenic microbes [30].


Microbial organisms commercially used as probiotics in dogs in Europe

To date, four bacterial strains/products have been examined by the European Food Safety Authority (EFSA) for their safety and efficacy as probiotics or feed additives in dogs. This includes two Enterococcus faecium strains (E. faecium NCIMB 10415 E1705, E. faecium NCIMB 10415 E1707), Lactobacillus acidophilus DSM 13241 25 and Bifidobacterium sp. animalis.

Both products containing an E. faecium strain had already been approved for the use in farm animals at the time approval for small animals was sought (2004). For one of these strains, EFSA's conclusion was that enough information was provided to consider it safe for the use in dogs and for humans having contact with treated dogs (E. faecium NCIMB 10415 E1707). Die ander E. faecium, strain NCIMB 10415 E1705, was considered unlikely to represent a hazard for the target species even when supplied in overdose. It was shown to not favour the growth and shedding of haemolytic and non-haemolytic E coli in dogs (and cats).

For the product containing Lactobacillus acidophilus DSM 13241 25, EFSA did not establish a safety concern, as the strain was sensitive to medically relevant antibiotics, with the exception of ciprofloxacin. As no data on the effect of this probiotic on shedding of intestinal pathogens in the dog were provided, and it was considered a potential respiratory sensitiser, further data were requested by EFSA before reaching a final conclusion (2004).

The latest probiotic strain assessed was Bifidobacterium animalis (2012). For this strain (no further strain designation or details are available), the requirements regarding the assessment of antibiotic resistances were not met (as the strain was resistant to clindamycin and the genetic basis of the resistance could not be established). Based on two studies provided, the effect of B. animalis on GI-related parameters in dogs was considered of questionable biological relevance and EFSA could not conclude the efficacy of this product.

Apart from the strains mentioned above, other probiotics or synbiotics are available as nutritional supplements in dogs, both in Europe and in the USA. Even though most products available in Europe to date contain the E. faecium strain NCIMB 10415 E1707, sometimes in combination with other bacterial strains and different prebiotics, the products themselves have mostly not been specifically approved or tested. Aan die ander kant, E. faecium NCIMB 10415 E1707 has been used most widely in experimental settings, to assess effect on immune function or gut health (see below). Other bacterial strains available as over-the-counter supplements for dogs contain different strains of Laktobacilli (L. acidophilus, L. casei, L. plantarum, L. paracasei, L. lactis, L. rhamnosus, L. salivarius), Bifidobakterieë (B. infantis, B. lactis, B. longum, B. bifidum), Bacillus subtilis of coagulans and in some cases yeasts (Saccharomyces cerevisiae) or other fungi (Aspergillus oryzae). However, limited data are available about the safety and efficacy of these microorganisms/products or the health claims associated with them. Some microorganisms other than E. faecium have been tested as probiotics in experimental settings in dogs. Byvoorbeeld Saccharomyces boulardii was investigated in a small pilot study presented as a congress abstract in dogs with IBD and protein-losing enteropathy (P-LE) (Bresciani et al. 2014 )]. It significantly improved clinical activity score and serum albumin levels compared to the placebo-treated control dogs (Bresciani et al. 2014). Apart from single bacterial strains tested in vitro (detailed below), some single- and multi-strain probiotic products have also been tested to a certain degree in a clinical setting in dogs. For most single-strain studies, this is limited to the use of E. faecium (Swanson et al. 2002 Sauter et al. 2006 Strompfová et al. 2006 Schmitz et al. 2015a ). Several probiotic cocktails have been used with variable effect. For example a mixture of lactobacilli that showed promising ex vivo results regarding creating a more tolerant microenvironment in the gut, did not significantly improve outcome when administered in a clinical trial (Sauter et al. 2006). In another study, strains from a product approved for the use in people (VSL#3) have been administered to dogs with IBD leading to some clinical and immunological improvement (Rossi et al. 2014). This includes four Laktobacilli (L. acidophilus, L. plantarum, L. paracasei, L. delbrueckii ssp. bulgaricus), three Bifidobakterieë (B. breve, B. longum, B. infantis) en Streptococcus thermophilus.


Gevolgtrekkings

Long-term intake of a diet that is high in fruit and legume fibre, typical of those brought up in a rural agrarian community, is associated with greater diversity and marked differences in the faecal microbiota. Identified in a number of recent studies, a high predominance of Prevotella aan Bacteroides is seen in contrast to faecal microbiota of those living in Westernised societies. A ‘Western’, high-animal fat/high-sugar diet (also typically low in fruit and vegetable fibre) decreases potentially beneficial Firmicutes (such as the Roseburia/Eubakterie group and Faecalibacterium spp. fermenting dietary plant polysaccharides to beneficial SCFAs) and promotes increased levels of bacteria from within the Proteobacteria phylum [including mucosa-associated enteric gut pathogens and pathobionts, such as adherent, invasive E coli (AIEC) seen in increased numbers in IBD].

Short-term dietary changes were thought to have only modest transient effects unless they are quite severe, e.g. severe energy restriction (>35% for 6 weeks), however recent evidence points to major effects following short-term consumption of diets that are exclusively animal- or plant-based, with animal-based diets increasing the abundance of bile-tolerant bacteria (including Bacteroides, Bilophila and AIEC) and reducing the Firmicutes metabolising dietary carbohydrates/fibre. In humans ingesting high-protein, carbohydrate-restricted ‘weight-loss’ diets, weight loss is accompanied by increase in abundance of Bacteroidetes, and reduction in the Roseburia/Eubakterie group of Firmicutes. Consequently, these diets are associated with a significant reduction in the proportion of butyrate in faecal and colonic SCFA concentrations within 4 weeks which may impact on available energy resource for colonocytes. Long-term adherence to such diets may increase risk of colonic disease. Specific carbohydrate exclusion of FODMAPs however, whilst providing gastrointestinal symptom relief for patients with IBS and increasing microbiota diversity, appears to lower relative abundance of key SCFA-producing bacteria, e.g. Clostridium cluster XIVa.

Intervention with prebiotics (dietary carbohydrate/fibre components that encourage the growth of ‘healthy’ bacteria), particularly fructo- and GOS, appear to promote increased abundance of Bifidobacteria within the intestinal microbiota. This bacterial genus is known to be more prevalent in the faeces of breast milk-fed than formula milk-fed infants, Bifodogenesis being promoted by prebiotic human milk oligosaccharides. In vivo animal and human studies also provide convincing evidence to suggest that fermentable RS can also selectively promote growth of specific beneficial bacterial populations, thereby improving intestinal health. However, volunteer studies and recent clinical trials, indicate that prebiotic responses show a high-degree of subject to subject variability, and they are also influenced by the initial composition of an individual's microbiota. More detailed analysis of the microbiota following dietary prebiotic supplementation is clearly needed.

Soluble dietary fibres (NSP), if not yet defined as impacting on the microbiome, are able to block bacteria–intestinal epithelial interactions of a range of enteric pathogens, including IBD mucosa-associated AIEC. Not all soluble plant fibres are equally effective, with acidic (pectic) NSP from plantain (bananas) and broccoli having so far proved particularly effective, and although addition of plantain fibre to the feed substantially reduced invasion by Salmonella in the chicken, further studies are clearly needed to evaluate any benefit in humans. It is worth noting though, that a ‘contrabiotic’ effect is a plausible explanation for the recent demonstration from the Nurses’ Health study that subjects in the highest quintile for fruit fibre intake had

50% lower risk for subsequent development of Crohn's disease. A combination of all these mechanisms effected by dietary fibre (insoluble and soluble components) likely explain many of the differences in microbiota associated with long-term ingestion of a diet rich in fruit and vegetable fibre.

An overview of the long-term and short-term impact of dietary fibre on the intestinal microbiome and metabolome has been presented in Figure 5.


Gevolgtrekkings

Alzheimer’s disease is the most diffuse incurable dementia, and the identification of a definitive therapeutic intervention is a major challenge of our time. Dysbiosis was demonstrated to be a relevant risk factor for AD [ [101] ], with lifestyle, geographical location, drug assumption and dietary habits continuously being capable of modifying the gut microbiota composition. Diet rich in saturated fat and simple carbohydrates increases the risk of dementia and a suboptimal diet is associated with a more severe impaired cognition in AD [ [189] ]. Differently, a high quality diet like the Mediterranean diet correlates with better cognitive status in healthy people with reduced risk of developing MCI and AD [ [190] ]. In this context, the possibility to modulate the composition of gut microbiota using probiotics, prebiotics and other dietary intervention represents a promising and sustainable approach. Dietary interventions are generally safe and more advantageous than drug-based therapies since probiotics, prebiotics and synbiotics are cheap and easy to handle, thus reducing the burden also for AD patient caregivers. Similarly, FMT was described as a promising procedure, although some adverse effects were documented in infections from Clostridium difficile [ [191] ] or ulcerative colitis [ [192] ], indicating that intersubject variability must be considered and that a long-term follow-up is necessary to assess the risks and benefits. Moreover, standardization of methods used for microbiota analysis (sampling, preservation and storage of samples, and analytic procedures) will facilitate comparison between studies, enhancing the reproducibility [ [193] ]. The rapid advances of metabolomics and informatics will help in managing the vast databases deriving from ongoing and short-coming microbiota studies.

Successful results depend upon the optimization of different factors including proper combinations of bacterial strains and nutrients, time of treatment, disease stage therefore the presence of specific procedures and guidelines are necessary to enhance effectiveness of gut microbiota modulation.

The identification of AD-specific signatures in gut microbiota together with a better knowledge of the molecular mechanisms triggered upon microbiota modification will contribute to identify multiple personalized interventions for decreasing AD risk, delaying the onset of the pathology, and counteracting the appearance or improving the clearance of AD hallmarks.


Leserinteraksies

Kommentaar

jim lee says

Wow, this article explains so much — thanks!
I went vegan 3 months ago, and have trouble tolerating soy, even after taking TWO Beano caps before a meal.
Now I know that people with a true soy intolerance may not be helped by Beano.
But I didn’t know that tempeh may be a good alernative — that’s good to know, ‘cuz I’ve been avoiding recipes with ANY soy.
Thanks again for the info.

rachel says

Can someone at WestonPrice tell me if AvoVida capsules made with Soy can cause extreme gas? There seems to be no online reports of this, yet it happens to my partner each time he takes it for arthritis pain. Please can anyone give me an answer on this?

Mila says

Very informative and useful, thank you !

lew lu says

I am chinese and eat many varieties of tofu without a problem except tonight. my friend used a generic store bought tofu vs my varieties from the asian markets, from fresh, juice or dehydrated. I am in pain!! I wonder if its gmo? or they “whey” the process it (pun intended)


Kyk die video: 1st year, Biology, Chapter 2, Carbohydrates. Oligosaccharides. Polysaccharides (Oktober 2022).