Effect of cinnamon essential oil on gut microbiota in the mouse model of dextran sodium sulfate-induced colitis.

Increasing evidence has confirmed that the antimicrobial and anti-inflammatory effects of cinnamon essential oil (CEO) contribute to protection against inflammatory bowel disease (IBD). The dextran sodium sulfate (DSS)-induced colitis mouse model was established to investigate the correlation between the protective effects of CEO and the regulation of intestinal microflora. The symptoms of IBD were assessed by measuring the hemoglobin content, myeloperoxidase activity, histopathological observation, cytokines, and toll-like receptor (TLR4) expression. The alteration of the fecal microbiome composition was analyzed by 16S rRNA gene sequencing. The results indicated that the oral administration of CEO enriched with cinnamaldehyde effectively alleviated the development of DSS-induced colitis. In contrast to the inability of antibiotics to regulate flora imbalance, the mice fed with CEO had an improved diversity and richness of intestinal microbiota, and a modified community composition with a decrease in Helicobacter and Bacteroides and an increase in Bacteroidales_S24-7 family and short-chain fatty acids (SCFA)-producing bacteria (Alloprevotella and Lachnospiraceae_NK4A136_group). Moreover, the correlation analysis showed that TLR4 and tumor necrosis factor-α was positively correlated with Helicobacter, but inversely correlated with SCFA-producing bacteria. These findings indicated from a new perspective that the inhibitory effect of CEO on IBD was closely related to improving the intestinal flora imbalance.

Oil Bodies Extracted from High-Fat and Low-Fat Soybeans: Stability and Composition During Storage.

Soybeans contain oil bodies (OBs) that encapsulate triacylglycerols (TAGs) with a phospholipid monolayer carrying scattered proteins. In nature, soybean OBs can form natural emulsions in aqueous media and may serve as natural, minimally processed, stable, and pre-emulsified oil for addition into appropriate food systems. In this study, OBs were obtained by aqueous extraction from the mature seeds of 2 soybean crop cultivars, high-fat soybean and low-fat soybeans. The compositions of the extracted OBs were analyzed during storage at room temperature up to 14 d (pH = 7). The oxidative stability of these OBs, stored at 60 °C, was evaluated by measuring the presence of primary (lipid hydroperoxides) and secondary lipid oxidation products (malondialdehyde) by determining the standard peroxide value (PV) and thiobarbituric acid-reactive substances (TBARS) value. During storage, the contents of unsaturated fatty acids, phospholipids, and tocopherols declined in both OBs, while their mean particle diameters (d32 ) and ζ-potentials increased. The changes in PV and TBARS values exhibited a similar trend for both OBs, but the OBs from low-fat soybeans had significantly lower PV and higher TBARS values than the OBs from high-fat soybean cultivars (P < 0.05). Overall, the OBs from both soybean cultivars had good stability during storage.

Effect of culturing conditions on the expression of key enzymes in the proteolytic system of Lactobacillus bulgaricus.

The proteolytic system of Lactobacillus bulgaricus breaks down milk proteins into peptides and amino acids, which are essential for the growth of the bacteria. The aim of this study was to determine the expressions of seven key genes in the proteolytic system under different culturing conditions (different phases, initial pH values, temperatures, and nitrogen sources) using real-time polymerase chain reaction (RT-PCR). The transcriptions of the seven genes were reduced by 30-fold on average in the stationary phase compared with the exponential growth phase. The transcriptions of the seven genes were reduced by 62.5-, 15.0-, and 59.0-fold in the strains KLDS 08006, KLDS 08007, and KLDS 08012, respectively, indicating that the expressions of the seven genes were significantly different among strains. In addition, the expressions of the seven genes were repressed in the MRS medium containing casein peptone. The effect of peptone supply on PepX transcription was the weakest compared with the other six genes, and the impact on OppD transcription was the strongest. Moreover, the expressions of the seven genes were significantly different among different strains (P<0.05). All these results indicated that the culturing conditions affected the expression of the proteolytic system genes in Lactobacillus bulgaricus at the transcription level.