The chemical composition and potential prebiotic effects of 4 different flours from varieties of sweet potato roots (SPR), including two with white peel and two with purple peel, cultivated in Northeastern Brazil were studied. SPR flours (SPRF) showed variable contents of soluble (1.8–3.0%) and insoluble (4.6–5.8%) fiber, resistant starch (6.2–10.3%), nystose (not found up to 7.1 g/l), kestose (1.7–5.4 g/l), phenolic compounds (phenolic acids: not found up to 16.9 mg/l, flavanols: not found up to 20.4 mg/l, flavanones: not found up to 26.0 mg/l) and sugars (fructose: 4.6–6.1 g/l, glucose: 5.4–8.7 g/l, maltose: 3.2–27.2 g/l). SPRF (20 g/l) with and without a simulated gastrointestinal digestion had an average positive prebiotic activity score (0.11–0.55) with probiotics Lactobacillus acidophilus, L. casei and Bifidobacterium animalis to the detriment of enteric competitors, showing selective stimulatory effects on beneficial bacteria species that are found as part of the gut microbiota. Cultivation of these probiotics in media with or without simulated digestion (SPRF, 20 g/l) showed high bacterial counts (8.2–9.7 log CFU/ml), decreased pH, increased acetic, formic, lactic, malic, succinic and tartaric acids and decreased fructose, glucose and maltose over time, which are indicative of strong metabolic activity. These results showed that flours from different SPR varieties are potential prebiotic ingredients for use in the formulation of functional foods or dietary supplements.

研究了巴西东北部种植的4种来自甘薯根（SPR）品种的面粉的化学组成和潜在的益生元效应，其中包括两种带有白皮和两种带有紫色皮的面粉。SPR面粉（SPRF）的可溶性纤维（1.8–3.0％）和不溶性纤维（4.6–5.8％），抗性淀粉（6.2–10.3％），猪st糖（7.1 g / l以下未发现），钾（1.7） –5.4 g / l），酚类化合物（酚酸：未发现高达16.9 mg / l，黄烷醇：未发现高达20.4 mg / l，黄烷酮：未发现高达26.0 mg / l）和糖（果糖：4.6 –6.1 g / l，葡萄糖：5.4–8.7 g / l，麦芽糖：3.2–27.2 g / l）。带有和不带有模拟消化道消化的SPRF（20 g / l）益生菌嗜酸乳杆菌，干酪乳杆菌和乳酸菌的平均益生菌平均阳性活动评分（0.11-0.55）。动物双歧杆菌对肠道竞争者有害，对肠道菌群的有益细菌具有选择性的刺激作用。在有或没有模拟消化（SPRF，20 g / l）的培养基中培养这些益生菌均显示出高细菌数（8.2–9.7 log CFU / ml），pH降低，乙酸，甲酸，乳酸，苹果酸，琥珀酸和酒石酸增加，以及随着时间的流逝，果糖，葡萄糖和麦芽糖的含量下降，这表明其代谢活性强。这些结果表明，来自不同SPR品种的面粉是潜在的益生元成分，可用于配制功能性食品或膳食补充剂。