Effect of lotus seed resistant starch on the bioconversion pathway of taurocholic acid by regulating the intestinal microbiota.

Taurocholic acid (TCA) is abundant in the rat intestine and has multiple health benefits. In the gut, intestinal microbiota can transform TCA into different bile acid (BA) derivatives, with the composition of microbiota playing a crucial role in the transformation process. This study aims to investigate how lotus seed resistant starch (LRS) can regulate microbiota to influence BA transformation. A fecal fermentation study was conducted in vitro, using either LRS, high-amylose maize starch (HAMS), or glucose (GLU) to analyze microbiota composition, BA content, and metabolic enzyme activities over different fermentation times. Bioinformatics analysis found that LRS increased the relative abundance of Enterococcus, Bacillus, and Lactobacillus, and decreased Escherichia-Shigella, compared with HAMS and GLU. LRS also reduced total BA content and accelerated the conversion of TCA to cholic acid, deoxycholic acid, and other derivatives. These results reveal that LRS and GLU tend to mediate the dehydroxy pathway, whereas HAMS tends to secrete metabolic enzymes in the epimerization pathway. Therefore, the evidence that LRS may regulate TCA bioconversion may benefit human colon health research and provide an important theoretical basis, as well as offer new concepts for the development of functional foods.

Bile acid and its bidirectional interactions with gut microbiota: a review.

Bile acids (BAs) are an important metabolite produced by cholesterol catabolism. It serves important roles in glucose and lipid metabolism and host-microbe interaction. Recent research has shown that different gut-microbiota can secrete different metabolic-enzymes to mediate the deconjugation, dehydroxylation and epimerization of BAs. In addition, microbes mediate BAs transformation and exert physiological functions in metabolic diseases may have a potentially close relationship with diet. Therefore, elaborating the pathways by which gut microbes mediate the transformation of BAs through enzymatic reactions involved are principal to understand the mechanism of effects between dietary patterns, gut microbes and BAs, and to provide theoretical knowledge for the development of functional foods to regulate metabolic diseases. In the present review, we summarized works on the physiological function of BAs, as well as the classification and composition of BAs in different animal models and its organs. In addition, we mainly focus on the bidirectional interactions of gut microbes with BAs transformation, and discuss the effects of diet on microbial transformation of BAs. Finally, we raised the question of further in-depth investigation of the food-gut microbial-BAs relationship, which might contribute to the improvement of metabolic diseases through dietary interventions in the future.

Effect of lotus seed resistant starch on small intestinal flora and bile acids in hyperlipidemic rats.

Ordinary and hyperlipidemic rats were gavaged with lotus seed resistant starch (LRS), and the structure of the small intestinal flora and bile acids composition were determined for four groups of rats to construct a relationship network diagram between different bacterial genera, bile acids and blood lipid profiles, revealing a microbial mechanism for the lipid-lowering effect of LRS in hyperlipidemic rats. LRS inhibited the growth of Romboutsia, Bacillus, Blautia, norank_f__Muribaculaceae and norank_f__Eubacterium_coprostanoligenes_group in hyperlipidemic rats. Meanwhile LRS promoted the production of primary bile acids (CA, CDCA, ß-MCA) and secondary bile acids (LCA, UDCA), and reduced the contents of TCA, Dehydro-LCA, isoLCA, LCA-3-S and THDCA in hyperlipidemic rats. Furthermore, Blautia, norank_f__Muribaculaceae and norank_f__Eubacterium_coprostanoligenes_group were positively correlated with Dehydro-LCA, isoLCA, TCA, LCA-3-S, TCHO, TG and LDL-C. In summary, LRS improves blood lipid levels by regulating small intestinal flora and accelerating the breakdown of cholesterol into bile acids in the liver.

Resistant starch from sweet potatoes: Recent advancements and applications in the food sector.

In tropical and subtropical areas, tuber and root crops are staple foods and a key source of energy. Sweet potato (SP) is currently regarded as one of the world's top ten foods because of its diverse sizes, shapes, color, and health benefits. The resistant starch (RS) content of SP is substantial. It is predicted to become the cheapest item in the food industry due to its extensive variety, food stability, emulsifier and fat substitution capabilities, and as filler. As a result, interest in SP-sourced RS has recently increased. Due to their unique nutritional and functional qualities, novelty has become a popular research focus in recent years. This review will summarize the current understanding of SP starch components and their impact on the technological and physicochemical properties of produced starch for commercial viability. The importance of sweet potato RS in addressing future RS demand sustainability is emphasized. SPs are a viable alternative to tubers as a sustainable raw material for RS production. It has an advantage over tubers because of its intrinsic nutritional value and climatic endurance. Thermal, chemical, and enzymatic treatments are effective RS manufacturing procedures. The adaptability of sweet potato RS allows for a wide range of food applications.

Synergistic Effects of Lotus Seed Resistant Starch and Sodium Lactate on Hypolipidemic Function and Serum Nontargeted Metabolites in Hyperlipidemic Rats.

The synergistic effects of lotus seed resistant starch (LRS3) and sodium lactate (SL; a postbiotics of RS3) on hypolipidemic function and serum nontargeted metabolites of hyperlipidemia rats were investegated. Rats fed a high-fat diet were orally administered with LRS3 (HLRS group) or SL (HSL group) either alone or in combination (HLRSSL group) for consecutive 4 weeks. HLRSSL was found to control weight gain, regulate blood lipid levels, reduce accumulation of fat in liver cells, and improve lesions in rat cardiac arteries, liver, small intestine, and colon tissues more effectively compared to HLRS or HSL group alone. Compared to the high-fat control group (HMC), l-phenylalanine and LysoPC(22:6(4Z,7Z,10Z,13Z,16Z,19Z)) in serum were upregulated in HLRSSL rats, while aconitic acid and suberic acid were decreased. Correlation analysis showed that SM(d18:0/16:1(9Z)), taurochenodeoxycholic acid, LysoPC(22:6(4Z,7Z,10Z,13Z,16Z,19Z)), oleic acid, and retinol were negatively correlated with total cholesterol (TCHO), triglyceride (TG), and low-density lipoprotein cholesterol (LDL-C) and positively correlated with high-density lipoprotein cholesterol (HDL-C). Moreover, glutamic acid and serine showed a significant positive correlation with LDL-C and negative correlation with HDL-C. These differential metabolites were associated with reducing serum lipid levels in hyperlipidemia rats potentially through metabolic pathways such as linoleic acid, glutamine and glutamate, pyruvate, citric acid cycle, and glycerophospholipid.

Lotus seed resistant starch affects the conversion of sodium taurocholate by regulating the intestinal microbiota.

We investigated the ability of lotus seed resistant starch (LRS) to affect the conversion of sodium taurocholate (STCA) by regulating the intestinal flora, using glucose (GLU) and high amylose corn starch (HAMS) as controls. The dominant microbiota in LRS group were mainly Lactobacillus and Escherichia_Shigella, with a small proportion of Bifidobacterium. Meanwhile, Lactobacillus, Bifidobacterium and Enterococcus were dominant microbiota in the HAMS group. Lactobacillus, Burkholderia-Caballeronia-Paraburkholderia and Sphingomonas were found in the GLU group. Furthermore, Bifidobacterium, Enterococcus and Escherichia_Shigella were negatively correlated with STCA and sodium taurodeoxycholate (STDCA), while these bacteria were positively correlated with bile salt hydrolase (BSH) and hydroxysteroid dehydrogenase (HSDH) content. Meanwhile Burkholderia-Caballeronia-Paraburkholderia and Sphingomonas were positively correlated with STCA and STDCA, while these bacteria were negatively correlated with BSH and HSDH content. LRS promoted the proliferation of Bifidobacterium and Escherichia_Shigella to secret more BSH and HSDH, accelerating the hydrolysis of STCA and reducing the conversion of STDCA.

Synergistic effect of lotus seed resistant starch and short-chain fatty acids on mice fecal microbiota in vitro.

This study aimed to investigate the synergistic effect of lotus seed resistant starch (LRS) and short-chain fatty acids (SCFAs) on mice fecal bacterial flora and the contents of SCFAs in vitro. Following 24 h of fermentation, 16S rRNA analysis revealed several differences in the fecal microbiota community structure among primal bacteria (PB), LRS and different SCFAs combined with LRS groups (SCFAs-LRS). The LRS group increased the relative abundance of Lactobacillus, Allobaculum, Clostridium, Bacteroides and Prevotella. Among the SCFAs-LRS group, AA-LRS increased the relative abundance of Prevotella, and Bacillus. PA-LRS increased abundance of Sphingomonas and the BA-LRS group significantly increased the relative abundance of Rhizobiales, Brucellaceae and Ochrobactrum. Meanwhile, propionic acid and BA productions significantly increased in the BA-LRS group. The SCFAs-LRS group elicited a beneficial effect on the fecal microbiota by increasing production of SCFAs. We highlight the fact that the combination of LRS and SCFA can increase the contents of SCFAs produced by mice fecal microbiota. In short, the combination of LRS and SCFA can influence intestinal flora by promoting the growth of beneficial bacteria and can serve as new prebiotics for promoting health and disease management.

Effect of lotus seed resistant starch on tolerance of mice fecal microbiota to bile salt.

We investigated the effect of lotus seed resistant starch (LRS) on mice fecal microbiota tolerance to bile salt by culturing organisms compared to inulin (INU) glucose (GLU) and waxy corn starch (WAX). Operational taxonomic units (OTUs) and diversity indices in LRS and INU groups were increased in the presence of 0.03% to 0.3% bile salt, while they were decreased in GLU, and OTUs were decreased in WAX. Specifically, LRS promoted proliferation of Lactobacillus, which potentially used bile acid, and inhibited growth of the potentially harmful bacteria Enterococcus and Staphylococcus. Moreover, Lactobacillus was negatively correlated with Salinicoccus and Granulicatella in GLU, LRS and INU groups at 1.5% bile salt. With LRS, amino acid metabolic pathways were increased while pathogens causing certain diseases were decreased. LRS increased the tolerance of mice fecal microbiota to bile salt by promoting the proliferation of bacteria utilizing bile acid and inhibiting the growth of harmful bacteria.

Effect of chitosan on the digestibility and molecular structural properties of lotus seed starch.

The effect of chitosan (CS) on the in vitro digestibility and molecular structural properties of lotus seed starch (LS), and the correlation matrix was studied. The addition of CS could delay the hydrolysis of LS due to a increased level of slowly digestible starch (SDS). LS-CS blends exhibited lower pasting viscosity, greater amylose content and higher ordered structure than LS alone. A significant correlation was found between the digestibility and molecular structural properties of LS-CS blends. Rapidly digestible starch content was positively correlated with viscosity and full width at half-maximum height (FWHH) at 480 cm-1; whereas, SDS content was negatively correlated with setback and FWHH. Moreover, CS concentration was positively related to absorbances at 1047 and 1035 cm-1and amylose content. The results indicated that the addition of CS could be beneficial to the formation of an ordered molecular structure in LS-CS blends and decreased digestibility in vitro.