Gut Microbiota Modulation by Dietary Barley Malt Melanoidins

Abstract

Melanoidins are the final Maillard reaction products (protein–carbohydrate complexes) produced in food by prolonged and intense heating. We assessed the impact of the consumption of melanoidins from barley malts on gut microbiota. Seventy-five mice were assigned into five groups, where the control group consumed a non-melanoidin malt diet, and other groups received melanoidin-rich malts in increments of 25% up to 100% melanoidin malts. Feces were sampled at days 0, 1, 2, 3, 7, 14, and 21 and the microbiota was determined using V4 bacterial 16S rRNA amplicon sequencing and short-chain fatty acids (SCFA) by gas chromatography. Increased melanoidins was found to result in significantly divergent gut microbiota profiles and supported sustained SCFA production. The relative abundance of Dorea, Oscillibacter, and Alisitpes were decreased, while Lactobacillus, Parasutterella, Akkermansia, Bifidobacterium, and Barnesiella increased. Bifidobacterium spp. and Akkermansia spp. were significantly increased in mice consuming the highest melanoidin amounts, suggesting remarkable prebiotic potential.

Colon Bioaccessibility under In Vitro Gastrointestinal Digestion of Different Coffee Brews Chemically Profiled through UHPLC-Q-Orbitrap HRMS

“…In fact, the increased bioaccessibility and antioxidant activity observed in assayed samples appeared to be attributable to the coffee melanoidins. According to the recent publications, coffee melanoidins escape digestion, similar to dietary fibers, and during the colonic stage they can become substrates for the gut microbiota, releasing antioxidant active molecules linked to them [ 44 , 45 , 46 ]. The released phenolics, especially CGAs, incorporated during the roasting of coffee beans, may exert a local effect in protection against colorectal cancer and provide important health benefits after absorption via epithelium cells [ 43 ].…”

Decontamination of mycotoxigenic fungi on shelled corn using selective infrared heating technique

“…Amplicon libraries were obtained following established protocols (Aljahdali et al., 2020). Briefly, PCR was performed at 94°C for 2 min; 30 cycles of 94°C for 30 s, 55°C for 30 s, and 68°C for 1 min; and a final extension at 72°C for 5 min.…”

Carbohydrates Profile, Polyphenols Content and Antioxidative Properties of Beer Worts Produced with Different Dark Malts Varieties or Roasted Barley Grains

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