In order to explore the impacts of limited hydrolysis combined with glycation modification on the structure, functional properties, allergenicity, and volatile compounds of silkworm pupae protein, the crude silkworm pupae protein was firstly extracted by alkaline-solution method, followed by Alcalase-treated limited hydrolysis for 10-30 min. Xylose was subsequently added and reacted for 1 h at 95 °C. Afterwards, the structure, functionality, allergenicity, and volatile compounds before and after modification were analysed. The molecular weight of modified silkworm pupae protein was remarkably decreased. The solubility was improved from 4.7 to 28.6%. The foaming ability was elevated by 21%. The in vitro digestibility was elevated by 34.0-44.4%. Furthermore, the abundance of six potential allergic proteins was remarkably reduced. In addition, the contents of off-flavour compounds in modified silkworm pupae proteins substantially decreased. Overall, limited hydrolysis combined with glycation modification can improve the functionality and flavour of silkworm pupae protein, while reduce the allergenicity.
The aim of this study was to investigate the mechanisms underlying the involvement of gut microbes in body weight gain of high-fat diet-fed obesity-prone (obese) and obesity-resistant (lean) mice. C57BL/6 mice were grouped into an obese group, a lean group and a normal control group. Both obese and lean mice were fed a high-fat diet while normal control mice were fed a normal diet; they were observed for six weeks. The results showed that lean mice had lower serum lipid levels, body fat and weight gain than obese mice. The ATPase, succinate dehydrogenase and malate dehydrogenase activities in liver as well as oxygen expenditure and rectal temperature of lean mice were significantly lower than in obese mice. As compared with obese mice, the absorption of intestinal carbohydrates but not of fats or proteins was significantly attenuated in lean mice. Furthermore, 16S rRNA abundances of faecal Firmicutes and Bacteroidetes were significantly reduced in lean mice. In addition, faecal β-D-galactosidase activity and short chain fatty acid levels were significantly decreased in lean mice. Expressions of peroxisome proliferator-activated receptor gamma 2 and CCAAT/enhancer binding protein-β in visceral adipose tissues were significantly downregulated in lean mice as compared with obese mice. Resistance to dyslipidaemia and high-fat diet-induced obesity was mediated by ineffective absorption of intestinal carbohydrates but not of fats or proteins, probably through reducing gut Bacteroidetes and Firmicutes contents and lowering of gut carbohydrate metabolism. The regulation of intestinal carbohydrates instead of fat absorption by gut microbes might be a potential treatment strategy for high-fat diet-induced obesity.
The Aspergillus terreus strain HNGD-TM15 that was isolated from soil grown with rosemary was shown to efficiently degrade aflatoxin B1 (AFB1). Specifically, AFB1 was degraded by the strain’s fermentation broth at a maximum degradation rate of 98.3%. HPLC and LC-MS analyses detected a degradation product with an m/z ion value of 312.0636. Its molecular formula was C18H39NO3, which was tentatively identified as 2-amino-1, 3,4-octadecatriol. Based on LC-MS results and further analysis, it was revealed that a series of reactions, such as decomposition, reduction (lactone ring hydrogenation) and substitution (hydrolysis), occurred during the degradation of AFB1. Therefore, A. terreus HNGD-TM15 has a great potential for application in the detoxification of AFB1 contaminating food and feed products.
To elucidate the role of the retinoid X receptor (RXR) in moulting and ovarian development of crustaceans, the full-length cDNA of RXR (PtRXR) in Portunus trituberculatus (Miers, 1876) was cloned by nested reverse transcriptase polymerase chain reaction (RT-PCR) and rapid amplification of cDNA ends (RACE). The cDNA sequence of PtRXR was determined to be 1365 bp in length and contained an open reading frame (ORF) of 1140 bp encoding a 379-amino-acid residue protein. The deduced amino-acid sequence of PtRXR shared high identities with other known RXRs. Phylogenetic analysis showed that PtRXR was clustered among crustacean RXRs and located closer to the vertebrate RXRs than the insect ultraspiracle (USP, an orthologue of RXR). Quantitative real-time PCR (qRT-PCR) was used to analyse the tissue distribution of PtRXR and its expression patterns during the moulting cycle and the second ovarian development of P. trituberculatus. The results showed that PtRXR was widely distributed in the tested tissues. PtRXR mRNA levels were significantly high in ovary and Y-organs (YO) of intermoult crabs. The mRNA levels of PtRXR in YO and mandibular organs (MO) decreased significantly from intermoult to premoult. In addition, PtRXR was expressed at each stage of the second ovarian development in ovary, hepatopancreas, YO and MO, and the expression levels reached maximal values when the ovary reached the final stage of maturation. These results indicate that PtRXR might have an important role in regulating the moulting and ovarian development of P. trituberculatus.
Aflatoxins are a group of toxic and carcinogenic fungal metabolites. They are commonly found in cereals, nuts
and animal feeds and create a significant threat to the food industry and animal production. Several strategies
have been developed to avoid or reduce harmful effects of aflatoxins since the 1960s. However, prevention of
aflatoxin contamination pre/post harvest or during storage has not been satisfactory and control strategies such as
physical removing and chemical inactivating used in food commodities have their deficiencies, which limit their
large scale application. It is expected that progress in the control of aflatoxin contamination will depend on the
introduction of technologies for specific, efficient and environmentally sound detoxification. The utilisation of
biological detoxification agents, such as microorganisms and/or their enzymatic products to detoxify aflatoxins in
contaminated food and feed can be a choice of such technology. To date, many of the microbial strategies have only
showed reduced concentration of aflatoxins and the structure and toxicity of the detoxified products are unclear.
More attention should be paid to the detoxification reactions, the structure of biotransformed products and the
enzymes responsible for the detoxification. In this article, microbial strategies for aflatoxin control such as microbial
binding and microbial biotransformation are reviewed.
This study investigated the effect of dietary mealworm meal on growth performance, body composition, and liver health of largemouth bass. During the feeding trial, all fish were feed to apparent satiation twice one day for 42 days with 4 experimental diets included 0, 10.35, 20.70, 31.50% mealworm meal (MWM) replacing graded levels of fishmeal (FM) (0%, MWM0; 25%, MWM25; 50%, MWM50; 75%, MWM75), respectively. The growth performance (weight gain rate, specific growth rate and feed efficiency) of largemouth bass were significantly decreased in the MWM50, and MWM75 groups. Liver lipogenesis and lipid contents were significantly higher in MWM75 group than in the MWM0 group. In MWM50 and MWM75, the structure of liver tissue was abnormal, and a large number of inflammatory cells infiltrated into the tissue. The transcriptional levels of tumour necrosis factor-α, interleukin- 1β, and interleukin-15 were significantly upregulated in MWM75 compared to MWM0. The activity of caspase 3 (casp3) and apoptosis was significantly higher in the MWM75 group than in the MWM0 group. The relative mRNA levels of casp3, casp9, casp8 and casp10 were upregulated in MWM50 and MWM75. It is concluded that MWM can replace 25% of FM in the diet of largemouth bass without negative effects on growth performance. However, high inclusions of MWM replacing more than 50% of dietary FM would lead to negative influences on growth and liver health of largemouth bass, partly through enhanced inflammation and apoptosis.
Acute diarrhoea continues to be a leading cause of morbidity, hospitalisation, and mortality worldwide, and probiotics have been proposed as a complementary therapy in the treatment of acute diarrhoea. The goal of this study is to assess the efficacy and safety of three combined probiotic strains, Bifidobacterium lactis Bi-07, Lactobacillus rhamnosus HN001, and Lactobacillus acidophilus NCFM, as an adjunct to rehydration therapy in treatment of acute watery diarrhoea in hospitalised children. Eligible diarrheal children were randomised into intervention group (IG, n=96, conventional treatment for diarrhoea in combination with probiotics) and control group (CG, n=98, conventional treatment for diarrhoea without probiotics). The primary assessments of this study were duration of diarrhoea and hospital stay and improvement in diarrhoea symptoms. Significantly more children in the IG showed improvements in diarrhoea (defined as a decrease of stool frequency to no more than four times per day and an improved stool consistency within 24-48 h after the treatment) than those in the CG (96.9 vs 79.6%, P<0.05). Children supplemented with the mixed strains had a 22.5 h shorter (121.4±13.7 h vs 143.9±19.8 h) mean duration of diarrhoea and 1.2 d shorter hospital stays (5.1±1.2 d vs 6.3±1.4 d) than children only receiving the rehydration therapy (P<0.05). The prevalence of constipation of children in the IG (3.1%) was markedly lower (P<0.05) than that of children in the CG (13.3%) after treatment. In conclusion, the mixture of three probiotic strains given to children aged 1-3 years resulted in shorter durations of diarrhoea and hospitalisation and a higher percentage of improved children.
In arthropods, the moult-inhibiting hormone (MIH), the ecdysone receptor (EcR), and the retinoid X receptor (RXR) are key regulators in moulting. In the present study, the full-length cDNAs of the MIH, EcR2, and RXR3 genes from the red swamp crayfish, Procambarus clarkii (Girard, 1852) (denoted as PcMIH, PcEcR2, and PcRXR3) were cloned. Tissue-specific and moult stage-specific mRNA expression patterns of these genes were detected by real-time quantitative polymerase chain reaction. PcMIH was detected only in the eyestalk, whereas PcEcR2 and PcRXR3 mRNA were expressed in all tissues tested. The highest levels of PcEcR2 and PcRXR3 were detected in the gill and hepatopancreas. Expression of PcMIH mRNA in the eyestalk increased from postmoult to peak in intermoult and then decreased in premoult. Expression of PcEcR2 mRNA in the eyestalk, hepatopancreas, and muscle increased from postmoult to peak in early premoult and then decreased. However, expression of PcEcR2 mRNA in the gill increased from postmoult to reach a maximum in intermoult and then decreased in premoult. Expression of PcRXR3 mRNA also fluctuated in the eyestalk, hepatopancreas, muscle, and gill, with a decrease from postmoult to late premoult. Expression of PcEcR2 and PcRXR3 mRNA increased relative to the control in the hepatopancreas and gill after unilateral and bilateral eyestalk ablation, which suggested that PcMIH can inhibit their mRNA expression. Double-stranded RNA-mediated RNA interference of PcRXR3 caused different changes in mRNA expression of these genes in different tissues and resulted in decreased expression of PcEcR2 mRNA, which suggested a collaborative relationship between PcEcR2 and PcRXR3.
Treatment of irritable bowel syndrome (IBS) remains challenging for clinicians. Probiotic fungi may act as candidate options for IBS treatment, but systematic evaluation of their clinical value remains scarce. This study is aimed to assess the efficacy and the safety of probiotic fungi for IBS treatment by means of systematic review and meta-analysis. PubMed, Embase, Web of Science, and the Cochrane Library, were searched up to June 2022. Randomised controlled trials recruited subjects with prescriptions of probiotic fungi were eligible. Efficacy and safety of probiotic fungi were re-evaluated. Continuous data were pooled to obtain standardised difference in means (SMD) with a 95% confidence interval. The search strategy identified 120 articles of which 7 trial assessing 883 subjects were included in the analysis. Systematic data support that Saccharomyces helps to relieve abdominal pain/discomfort (SMD = −0.205, ), and presented potential improvements on psychological outcomes, stool form for IBS patients. It is hard to demonstrate favourable effects on other symptoms (including distension, mucus passage, sense of incomplete evacuation, urgency, straining). The incidence of mild complications ranged from 0 to 51.4%, but no serious complications were observed in the included trials. Therefore, the partial response and the relative safe of probiotic fungi for IBS treatment have been demonstrated from the existing trials. However, it is premature to eventually declare the practical effects of probiotic fungi. Conducting more high-quality and large-scale trials and real-world studies, or even developing new fungal strains, is still necessary.