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The soaking process of glutinous rice allows the growth and reproduction of microorganisms, which can easily cause food safety problems. In this work, the effects of different ultrasonic powers (150 W, 300 W, 450 W, and 600 W) on the bactericidal effect of glutinous rice, the physicochemical properties of starch and the quality characteristics of sweet dumplings were studied. Compared with soaking for 0 and 2 h, sonication of glutinous rice after soaking for 4 h was more effective at reducing the number of microorganisms in soaked glutinous rice, and the bactericidal effect increased with increasing ultrasound intensity. After 30 min, the total number of bacteria decreased by 2.04 log CFU/g. Moreover, ultrasonic treatment destroys the grain structure of glutinous rice starch, resulting in the formation of dents and cracks on the starch surface, increasing the amylose content, improving its expansion, reducing its short-range order and relative crystallinity, and altering its gelatinization characteristics. In addition, ultrasonic treatment increased the soup transparency of sweet dumplings from 51.8 % to 63.95 %, reducing their hardness, chewiness and adhesiveness. In summary, ultrasonic treatment can not only effectively kill microorganisms in soaked glutinous rice but also improve the quality of glutinous rice dumplings by changing the physicochemical properties of glutinous rice starch. The results of this study provide theoretical support for the application of ultrasonic technology in glutinous rice food production.

This study aimed to explore the effects of three medicinal plant (Perilla frutescens, Illicium verum, and Artemisia annua) extracts on growth, immune function and microflora of largemouth bass (Micropterus salmoides). Four isonitrogenous and isolipidic diets were formulated: basic feed (control, CON), 0.075% extracts of Perilla frutescens (PFE), Illicium verum (IVE), or Artemisia annua (AAE) feed. Apparently healthy fish (initial body weight of 8.20 ± 0.03 g; total number of 300) were randomly assigned into four groups in triplicate 25 fish tanks, and fish were fed with each of the four experiment feeds for 80 days. Compared with the CON group, groups IVE and AAE fish significantly improved growth performance (final weight, weight gain rate, and specific growth rates; P < 0.05) and decreased hepatic lipid content and hepatopancreas somatic index. Groups IVE and AAE significantly enhanced the hepatic antioxidant capacity (Catalase, Glutathione peroxidase dismutase, and Superoxide dismutase), and up-regulated the mRNA levels of hepatic tight junction protein (Occluding-1 and Claudin-1; P < 0.05) and anti-inflammatory cytokines (interleukin-10 and transforming growth factor-β; P < 0.05). In addition, groups IVE and AAE decreased the transaminase activity and the contents of D-lactic acid in serum (P < 0.05). Groups PFE and AAE significantly improved albumin and globulin contents in serum immunity (P < 0.05). In addition, IVE and AAE groups significantly increased the α-diversity of intestinal flora, reduced the abundance of underlying harmful bacteria (Plesiomonas and Aeromonas), and increased the abundance of probiotics bacteria (Lactobacillus and Weissella; P < 0.05). These results demonstrate that supplementation of feed with IVE and AAE can improve the immune function and change the abundance of intestinal flora, ultimately increasing growth of largemouth bass. Overall, PFE group did not perform well compare with the IVE and AAE groups.

Polysaccharide is the major biologically active constituent in functional mushroom Ganoderma lucidum. This study was aim to investigate the utilizability of G. lucidum polysaccharide by human fecal microbiota and its prebiotic potential based on the Simulator of Human Intestinal Microbial Ecosystem (SHIME). GLP was obtained from fruiting bodies of G. lucidum with average molecular weight of 133.1 KDa. Short-term colonic fermentation of GLP revealed the continuously decreased contents of total carbohydrates and reducing sugar as well as pH. Gas chromatography analysis indicated that GLP promoted the production of acetic, propionic and butyric acids. The 16S rDNA amplicon sequencing analysis showed that GLP improved the microbial diversity and ratio of Bacteroides to Firmicutes., and sharply enriched Bacteroides ovatus and B. uniformis. Therefore, GLP can be utilized by human fecal microbiota and then modify microbial community and metabolic function, and may serve as novel prebiotics to bring health benefits for human.

Ichthyophthirius multifiliis, an external fish parasite, often causes significant economic damage to the aquaculture industry. Since the use of malachite green was banned, the search of alternative substance to control I. multifiliis infections becomes stringent. In present study, in vitro and in vivo anti-ich efficacies of isopsoralen and psoralidin, two active compounds isolated from methanol extract of Psoralea corylifolia by bioassay-guided fractionation based on the efficacy of anti-ich encysted tomonts, were evaluated. In vitro antiprotozoal efficacy of psoralidin is much better than that of isopsoralen. Psoralidin can kill all theronts at concentrations of 0.8 mg/L or more during 4 h exposure; and terminate reproduction of I. multifiliis post 6 h exposure of protomonts to 0.9 mg/L and encysted tomonts to 1.2 mg/L. In vivo trials showed that 5 h exposure of infected fish to 2.5 mg/L of psoralidin significantly reduced the number of theronts released from tomonts. Furthermore, we observed that a part of protomonts, collected from infected fish post treatment, presented characteristic morphological changes of apoptosis after staining with Annexin V-EGFP/propidium iodide, indicating the possible mechanism of psoralidin against I. multifiliis trophont in situ. On the basis of these results, psoralidin can be used as a potential lead compound for the development of commercial drug against I. multifiliis.