Food and Biobased Products, AgResearch Ltd., Hamilton, New Zealand.
Smart Foods Innovation Centre of Excellence, AgResearch Ltd., Palmerston North, New Zealand.
PeerJ. 2022 May 10;10:e13415. doi: 10.7717/peerj.13415. eCollection 2022.
Milk, the first food of mammals, helps to establish a baseline gut microbiota. In humans, milk and milk products are consumed beyond infancy, providing comprehensive nutritional value. Non-dairy beverages, produced from plant, are increasingly popular as alternatives to dairy milk. The nutritive value of some plant-based products continues to be debated, whilst investigations into impacts on the microbiome are rare. The aim of this study was to compare the impact of bovine milk, soy and almond beverages on the rat gut microbiome. We previously showed soy and milk supplemented rats had similar bone density whereas the almond supplemented group had compromised bone health. There is an established link between bone health and the microbiota, leading us to hypothesise that the microbiota of groups supplemented with soy and milk would be somewhat similar, whilst almond supplementation would be different.
Three-week-old male Sprague Dawley rats were randomly assigned to five groups ( = 10/group) and fed for four weeks. Two control groups were fed either standard diet (AIN-93G food) or AIN-93G amino acids (AA, containing amino acids equivalent to casein but with no intact protein) and with water provided . Three treatment groups were fed AIN-93G AA and supplemented with either bovine ultra-heat treatment (UHT) milk or soy or almond UHT beverages as their sole liquid source. At trial end, DNA was extracted from caecum contents, and microbial abundance and diversity assessed using high throughput sequencing of the V3 to V4 variable regions of the 16S ribosomal RNA gene.
Almost all phyla (91%) differed significantly (FDR < 0.05) in relative abundance according to treatment and there were distinct differences seen in community structure between treatment groups at this level. At family level, forty taxa showed significantly different relative abundance (FDR < 0.05). Bacteroidetes () and Firmicutes populations (, and increased in relative abundance in the AA almond supplemented group. Supplementation with milk resulted in increased abundance of Actinobacteria ( and ) compared with other groups. Soy supplementation increased abundance of some Firmicutes ( but not Actinobacteria, as previously reported by others.
Supplementation with milk or plant-based drinks has broad impacts on the intestinal microbiome of young rats. Changes induced by cow milk were generally in line with previous reports showing increased relative abundance of whilst soy and almond beverage did not. Changes induced by soy and almond drink supplementation were in taxa commonly associated with carbohydrate utilisation. This research provides new insight into effects on the microbiome of three commercially available products marketed for similar uses.
牛奶是哺乳动物的第一食物，有助于建立肠道微生物群的基线。在人类中，牛奶和奶制品的消费超出了婴儿期，提供了全面的营养价值。非乳制品由植物制成，作为牛奶的替代品越来越受欢迎。一些植物性产品的营养价值仍在争论中，而对微生物组影响的调查很少。本研究的目的是比较牛奶、大豆和杏仁饮料对大鼠肠道微生物群的影响。我们之前表明，补充大豆和牛奶的大鼠具有相似的骨密度，而补充杏仁的大鼠的骨骼健康受损。骨骼健康与微生物群之间存在既定联系，这使我们假设补充大豆和牛奶的大鼠的微生物群会有些相似，而杏仁的补充则会有所不同。
3 周龄雄性 Sprague Dawley 大鼠随机分为 5 组（每组 10 只），并喂养 4 周。两组对照组分别喂食标准饮食（AIN-93G 食物）或 AIN-93G 氨基酸（AA，含有与酪蛋白相当的氨基酸，但没有完整的蛋白质），并提供水。三组处理组喂食 AIN-93G AA，并补充牛超高温处理（UHT）牛奶或大豆或杏仁 UHT 饮料作为其唯一的液体来源。试验结束时，从盲肠内容物中提取 DNA，并使用 16S 核糖体 RNA 基因的 V3 到 V4 可变区的高通量测序评估微生物丰度和多样性。
几乎所有门（91%）根据处理显著不同（FDR < 0.05），在群落结构方面，处理组之间存在明显差异。在科水平上，40 个分类群表现出显著不同的相对丰度（FDR < 0.05）。拟杆菌门（）和厚壁菌门（）的种群（、和）在 AA 杏仁补充组中的相对丰度增加。与其他组相比，牛奶补充导致放线菌（和）的丰度增加。大豆补充增加了一些厚壁菌门（但不是放线菌，如其他人先前报道的那样。
牛奶或植物性饮料的补充对幼鼠的肠道微生物群有广泛的影响。牛奶奶粉引起的变化通常与先前的报道一致，表明相对丰度增加，而大豆和杏仁饮料则没有。大豆和杏仁饮料补充引起的变化与通常与碳水化合物利用相关的分类群有关。这项研究为三种商业化产品对微生物组的影响提供了新的见解，这些产品以类似的用途销售。
