Digestive Activity Research Articles

SCAV-3 affects apoptotic cell degradation in Caenorhabditis elegans.

As the final step in apoptosis, apoptotic cells (ACs) are swiftly removed by specialized phagocytes, such as macrophages, or nonprofessional phagocytes, such as epidermal cells. Genetic studies of model organisms such as Caenorhabditis elegans have helped to elucidate the mechanisms of AC clearance and the underlying causes of disorders related to the dysregulation of these pathways. C. elegans possesses six class B scavenger receptor homologs, but whether they affect apoptosis is unknown. Here, we show that only the loss of function of scav-3, the C. elegans homolog of human lysosomal integral membrane protein-2, resulted in a considerable accumulation of cell corpses, which was caused by a failure in degradation rather than engulfment. SCAV-3 was found to be widely distributed and localized in lysosomes to maintain the integrity of the lysosomal membrane. Further study revealed that loss of scav-3 had no effect on phagosome maturation or the recruitment of lysosomes to phagosomes carrying cell corpses. Moreover, we discovered that the hydrolytic enzymes contained in the lysosomes were reduced in phagosomes in scav-3 mutants. Thus, hydrolases may leak from the damaged lysosome during phagolysosome formation due to the loss of scav-3 function, which reduces lysosome digestion activity and thus directly contributes to the elimination of ACs.

The effects of heat-moisture treatment on resistant starch levels in cassava and on fermentation, methanogenesis, and microbial populations in ruminants.

Resistant starch (RS) is difficult to digest in the digestive tract. This study aimed to evaluate the effects of heat-moisture treatment (HMT) on RS in cassava and examined its impact on rumen fermentation. Cassava flour was used as a raw material and used in a randomized block design with four different cycles of HMT as the treatments and four different rumen incubations in vitro as blocks. Treatments included: HMT0: without HMT (control), HMT1: one HMT cycle, HMT2: two HMT cycles, and HMT3: three HMT cycles. Heat-moisture treatment processes were performed at 121°C for 15 min and then freezing at -20°C for 6 h. Analyzed HMT cassava starch characteristics included components, digestibility, and physicochemical properties. In in vitro rumen fermentation studies (48 h incubation) using HMT cassava, digestibility, gas production, methane, fermentation profiles, and microbial population assessments were performed. Heat-moisture treatment significantly reduced (p < 0.05) starch, amylopectin, rapidly digestible starch (RDS), and slowly digestible starch levels. In contrast, amylose, reducing sugars, very RDS, RS, and protein digestion levels were significantly increased (p < 0.05). Additionally, a reduced crystallinity index and an increased amorphous index were observed in starch using Fourier-transform infrared analyses, while a change in crystalline type from type A to type B, along with a reduction in crystallinity degree, was observed in X-ray diffraction analyses. Heat-moisture treatment significantly (p < 0.05) reduced rumen dry matter (DM) degradation, gas production, methane (CH4 for 12 h), volatile fatty acid (VFA), and propionate levels. In addition, acetate, butyrate, and acetate/propionate ratios, as well as population of Streptococcus bovis and Bacteroides were significantly increased (p < 0.05). However, pH, ammonia, and organic matter digestibility were unaffected (p > 0.05) by HMT. Cassava HMT altered starch characteristics, significantly increased RS, which appeared to limit rumen digestion activity, decreased rumen DM degradation, gas production, VFAs, and CH4 production for 12 h, but increased S. bovis and Bacteroides levels.

Large-scale micro-aerobic digestion studies at municipal water resource recovery facilities for process-integrated biogas desulfurization

Biogas generated from anaerobic digestion processes typically requires gas conditioning including hydrogen sulfide removal before it is used on-site to generate electricity and heat or before upgrading to biomethane for gas pipeline distribution or vehicle fuel. Experiments of process-integrated micro-aeration in three different large-scale sludge digesters (effective volume 2450 m3, 3250 m3 and 3300 m3) were undertaken at municipal wastewater treatment plants and compared with large-scale applications reported in literature. This work discusses critical process parameters, advantages, and potential limitations of micro-aerobic digestion in comparison with other commonly used biogas desulfurization methods. It shows that high H2S reduction in the biogas can be obtained and that the H2S reduction is dependent not only on the air injection rate and location, but also on the digestion activity identified by the volumetric biogas production. Reliability testing of typical micro-aerobic upset scenarios and long-term micro-aerobic digester operation as part of this study provided deeper insights in the MA process that could also provide valuable input to what operational, maintenance and safety measures should be considered when applying micro-aeration in large-scale digesters. The large-scale micro-aerobic digestion trials demonstrated that the hydrogen sulfide concentration in the biogas can be controlled using minimal plant upgrades, contributing to the sustainability and economic efficiency of the energy recovery process of waste sludge digestion at water resource recovery facilities.

Inulin Supplementation in Diets for Tropical Gar (Atractosteus tropicus) Larvae: Effects on Growth, Survival, and Digestive and Antioxidant Enzyme Activities

The effect of adding inulin to balanced diets for tropical gar (Atractosteus tropicus) larvae on growth, survival, digestive enzyme activity, and antioxidant activity was evaluated. The diets were supplemented with 0.5, 1.0, 1.5, 2.0, and 2.5% inulin in addition to a control diet (0% inulin). A total of 1800 larvae of A. tropicus distributed in 18 tanks were used; the larvae were fed five times a day (8:00, 11:00, 13:00, 15:00, and 18:00) with Artemia nauplii from the absorption of the yolk (from 3–7 days after hatching, DAH) up to 10 DAH, which was mixed with the experimental feeds from 8–11 DAH (co-feeding) and exclusively with the balanced diets from 12 DAH to 21 DAH. Larvae fed the control diet (0% inulin) had the highest growth in weight and length, followed by fish fed the 2.5 and 2.0% inulin inclusions. However, survival showed that the fish fed with the inclusion of 2.5% inulin had the highest percentage (34.7%) compared to the rest of the treatments. On the other hand, the highest digestive enzymatic activities (acid and alkaline proteases, amylase, and lipase) were recorded in the larvae fed with 2 and 2.5% inulin. Likewise, catalase (CAT) and superoxide dismutase (SOD) activities were higher in larvae fed the control diet with 0% inulin. Supplementation of 2.0% to 2.5% inulin in the diet is recommended for A. tropicus larvae as it improves survival and digestive enzyme activity during this early stage of life.

In vitro hypoglycemic and antioxidant activities of steamed Polygonatum cyrtonema Hua with various steaming degrees: Relationship with homoisoflavonoids

Polygonatum cyrtonema Hua, an edible and medicinal plant in China, is usually steamed and then dried before use. Changes in homoisoflavonoids composition, radical scavenging activity, starch digestive enzyme inhibitory activity, cell glucose consumption and intracellular ROS formation of steamed P. cyrtonema Hua rhizome with various steaming degrees were investigated. Nine homoisoflavonoids were identified in raw and steamed rhizome extracts, and their contents were almost increased with increasing steaming degree. Steamed rhizome extract had increased activities to scavenge free radicals, reduce ferric iron, and inhibit α-amylase and α-glucosidase. The treatment with dark-steamed and deep-dark-steamed rhizome extracts restored glucose consumption in IR-HepG2 cells to normal level, and suppressed ROS level to that of Trolox treated group. Multivariate analyses (heat-map, correlation coefficient and PCA) indicated that the hypoglycemic and antioxidant activities of steamed rhizome depended on steaming degree, and were significantly correlated with disporopsin and 5,7,2′,4′-tetrahydroxy-6-methyl-homoisoflavanone (p < 0.05). Overall, these results suggested that steaming degree had remarkable impacts on homoisoflavonoids composition and bioactivities of P. cyrtonema Hua rhizome, and homoisoflavonoids greatly contributed to these activities.

Interactive effects of culture systems (biofloc and clear water) and dietary protein levels on growth, digestive activity, mucosal immune responses, antioxidant status, and resistance against salinity stress in the Caspian roach (Rutilus caspicus) fry

This experiment aimed to evaluate effects of culture system and dietary protein level on performance of the Caspian roach fry. Fish (0.99 ± 0.06 g) were stocked into 12 tanks (water volume, 50 L) at a stocking density of 100 fish per tank. The experiment was designed with two culture systems (biofloc, BFT and clear water, CW) each with 38 and 28% dietary protein levels following a 2 × 2 factorial design. After 60 days, fifty fish were randomly captured from each tank and exposed to salinity challenge (13 g/L) for 72 h. On days 45 and 60, total ammonia nitrogen (TAN) values were significantly higher in CW treatments, then BFT38 treatment, and lower in BFT28 treatment. The final weight, weight gain, and SGR in BFT and CW38 treatments were significantly higher and FCR was lower than the CW28 treatment. The protein efficiency ratio was highest in the BFT28 treatment. Also, amylase, lipase, and protease activities in fish cultured in BFT system were significantly higher than the CW system. After salinity stress, skin mucus cortisol values were significantly lower and survival rate was higher in BFT groups compared to the CW treatments. After 72 h stress, the mucus glucose values in BFT and CW38 treatments were significantly lower than the CW28 treatment. Before stress, the mucus alkaline phosphatase (ALP) activity was lowest in the CW28 treatment. Skin mucus protease activity was significantly higher in BFT groups at before and all sampling times after salinity challenge. The skin mucus lysozyme activity and total protein value in all treatments increased at 24 h post stress, and then only returned to the pre-stress values at 48 h for the BFT38 treatment. After salinity stress, lysozyme activity in BFT and CW38 treatments was significantly lower than the CW28 treatment. After 48 h stress, the highest mucus ACH50 activity was observed in the BFT38 treatment, but it was not significantly different from the BFT28 and CW38 treatments. After salinity stress, muscle catalase and SOD activities were significantly higher and MDA content was lower in BFT treatments than the CW treatments, suggesting that biofloc can enhance the antioxidant defense in fish. Overall, biofloc system and high dietary protein level beneficially affect growth, skin mucus immune responses, and resistance against salinity challenge in fish. Also, microbial proteins contained in bioflocs as a supplemental protein source can compensate 10% reduction of protein in the Caspian roach fry diet.

Identification of peptides from camel milk that inhibit starch digestion

The inhibition of starch digestion activities by peptides derived from camel milk proteins was determined and the effect of their amino acids charge and/or hydrophobicity was assessed. Starch digestion by pancreatic and brush border enzymes was assessed in vitro with a peptide to starch ratio of 1:3 (w/w). Hydrolysed whey proteins were more inhibitory than hydrolysed casein. Successive chromatographic separation of peptides enriched positively charged peptides with hydrophobic amino acids. Whey protein hydrolysate inhibited starch hydrolysis by 16%; peptide fractions recovered after CEX and HIC inhibited starch hydrolysis by 33–36%. Peptides in the active fractions were identified by LC–MS/MS and the inhibitory activity of 6 synthetic peptides was evaluated. Two of these six peptides, LALDIEIATYR and VLDELTLAR, inhibited starch hydrolysis by 34–37%. In conclusion, specific peptides that are produced before or during in vitro digestion can inhibit starch digestion and may moderate postprandial blood glucose levels in vivo.

Effects of dietary costmary (Tanacetum balsamita) essential oil on growth performance, digestive enzymes' activity, immune responses and subjected to ambient ammonia of common carp Cyprinus carpio

The present study aimed at investigating the effects of dietary costmary, Tanacetum balsamita, essential oil (CEO) on growth performance, digestive enzymes' activity, and physiological responses to ammonia exposure in common carp, Cyprinus carpio. Common carp (∼17 g) were randomly distributed in 15 tanks as five treatments receiving diets containing 0 (CTL), 100 (100E), 200 (200E), 300 (300E), and 400 (400E) mg/kg CEO for eight weeks and then exposed to 0.5 mg/l unionized ammonia nitrogen for 3 h. The results showed that dietary CEO significantly increased growth performance and feed efficiency and the best values were observed in 100E and 200E treatments. Intestinal amylase, lipase, and protease activities significantly increased in 100E, 200E, and 300E treatments, compared to CTL, and the highest amylase activity was related to 100E, and highest lipase and protease was related 100E and 200E treatments. Dietary CEO significantly decreased serum cortisol, glucose, catalase, malondialdehyde, alanine aminotransferase, aspartate aminotransferase, triglyceride, cholesterol, and low-density lipoprotein, but increased serum superoxide dismutase, glutathione peroxidase, lysozyme, complement, total immunoglobulin, high density lipoprotein, total protein, and albumin before and/or after ammonia stress, depending on CEO concentrations. Based on the present results, dietary CEO supplementation can improve digestive enzymes and growth performance of common carp. Moreover, CEO exhibits anti-stress, antioxidant, hepatoprotective, and immunostimulant effects in common carp under ammonia toxicity. Based on the results, 100–200 mg/kg CEO is recommended for common carp feed supplementation.

Genotoxins: The Mechanistic Links between Escherichia coli and Colorectal Cancer.

Emerging evidence indicates bacterial infections contribute to the formation of cancers. Bacterial genotoxins are effectors that cause DNA damage by introducing single- and double-strand DNA breaks in the host cells. The first bacterial genotoxin cytolethal distending toxin (CDT) was a protein identified in 1987 in a pathogenic strain in Escherichia coli (E. coli) isolated from a young patient. The peptide-polyketide genotoxin colibactin is produced by the phylogenetic group B2 of E. coli. Recently, a protein produced by attaching/effacing (A/E) pathogens, including enteropathogenic and enterohemorrhagic E. coli (EPEC and EHEC) and their murine equivalent Citrobacter rodentium (CR), has been reported as a novel protein genotoxin, being injected via the type III secretion system (T3SS) into host cells and harboring direct DNA digestion activity with a catalytic histidine-aspartic acid dyad. These E. coli-produced genotoxins impair host DNA, which results in senescence or apoptosis of the target cells if the damage is beyond repair. Conversely, host cells can survive and proliferate if the genotoxin-induced DNA damage is not severe enough to kill them. The surviving cells may accumulate genomic instability and acquire malignant traits. This review presents the cellular responses of infection with the genotoxins-producing E. coli and discusses the current knowledge of the tumorigenic potential of these toxins.

Preparation and structural characterization of acid-extracted polysaccharide from Grifola frondosa and antitumor activity on S180 tumor-bearing mice

In this study, an acid-extracted polysaccharide (GFP-A) was extracted from the fruiting bodies of G. frondosa with 1 % hydrochloric acid solution. Our study aimed to imitate the processes of digestion, absorption and antitumor activities of polysaccharides from G. frondosa under the acid environment of stomach in the body. The preliminary structural analysis resulted that GFP-A (about 1.10 × 106 Da) was a neutral polysaccharide composed of xylose, mannose, glucose (molar ratio: 0.12:1.00:6.98) with α-type glycosidic linkages. Additionally, antitumor activities on S180 tumor-bearing mice showed that GFP-A could effectively inhibit the growth of S180 tumor cells by protecting immune organs (thymus and spleen), activating immune cells (NK cells, lymphocytes and macrophages), upregulating the secretion of serum cytokines (TNF-α, IL-2 and IFN-γ) in vivo. H & E staining and cell cycle determination further demonstrated that GFP-A could induce S180 tumor cells apoptosis via arresting them in G1 phase. These results demonstrated that GFP-A could provide a theoretical basis for treatment of cancer.

Changes in Juvenile Rainbow Trout (Oncorhynchus mykiss) Growth Performance, Digestive Enzyme Activity, Hematological Profile and Serum Biochemical Markers After Dietary Administration of γ-irradiated Cinnamon (Cinnamomum verum) Ethanolic Extract

The aim of this study was to investigate the effects of dietary supplementation of γ-irradiated cinnamon ethanolic extract on the growth performance, digestive enzymes, lysozyme activity level and hematological factors in the juvenile rainbow trout. The fish were divided into five groups, including control group and four experimental groups (received diets enriched with 10 g/kg of non-irradiated or irradiated CEE at the radiation doses of 10, 20 and 40 KGy. At the end of the feeding trial (60` days), 10 fish were sampled from each tank after 12 h of feed deprivation. The results showed that the fish dietary irradiated CEE at doses of 10 KGy and 20 KGy had significantly higher final weights, weight gain, specific growth rates and growth hormone levels, and lower feed conversion ratios compared to the other groups (P≤0.05). The blood glucose level significantly lowered in the fish group fed with dietary γ-irradiated CEE, and increased the activity of lysozyme activity level and digestive enzymes compared to the control group (P≤0.05). In conclusion, dietary supplementation of γ-irradiated CEE at a dose of 10 KGy can enhance the positive effects of cinnamon extract and improve the growth performance, digestion and lysozyme activity in juvenile rainbow trout.

Effects of microbe-derived antioxidants on growth, digestive and aminotransferase activities, and antioxidant capacities in the hepatopancreas of Eriocheir sinensis under ammonia nitrogen stress

This study evaluated the effects of feeding a microbial-derived antioxidant diet (MA) for 56 days on the growth performance of Eriocheir sinensis, as well as on digestive and metabolic enzyme activity and antioxidant capacity under ammonia stress (400 mg/L ammonia nitrogen for 48 h). The weight gain at 28d and the specific growth rate at 56ds for crabs in the MA group were significantly higher than those in the control diet (C) group (p < 0.05). Compared with the C group, the color of the hepatopancreas in the MA group was significantly improved (p < 0.05). A significant decrease in the level of Hemolymph ammonia was found in the microbial antioxidant ammonia-N (MA_A) group (p < 0.05), which may be related to the decrease of transaminase (AST, ALT, GDH) activities caused by MA diet (p < 0.05). There is a significant increase in the digestive enzyme activities (Trypsin and Lipase), which reduced the accumulation of triglycerides in the hepatopancreas in the (MA_A) group (p < 0.05). In addition, the antioxidant damage of crabs in hepatopancreas caused by ammonia nitrogen toxicity could also significantly be improved by MA fed in the (MA_A) group (p < 0.05). microbe-derived antioxidants (supplemented with 0.2% in feeds) can protect the health of hepatopancreas, promote growth, and improve the ability to resist ammonia nitrogen stress for E.sinensis.

Co-assembly-mediated biosupramolecular catalysis: thermodynamic insights into nucleobase specific (oligo)nucleotide attachment and cleavage.

Gaining control over the stability and cleavage of phosphoester and phosphodiester remains a matter of interest for their application in biotechnology to oligonucleotide-based therapeutics. Herein, we report an efficient unactivated phosphoester hydrolysis (stable mono/di/tri/cyclic nucleotide to nucleoside conversion) via a biosupramolecular system comprising of a non-covalent complex of enzyme, alkaline phosphatase (ALP), and Zn(II)-metallosurfactant. We also demonstrate the nucleobase selective activation or inhibition of ALP-mediated oligonucleotide digestion process using that complex. The higher binding affinity of Zn(II)-containing headgroup with phosphate-containing substrate enhanced the effective substrate concentration surrounding the enzyme, which, in turn, results in a drastic decrease in the Michaelis constant (KM), along with an increase in the turnover (kcat). The catalytic activation or inhibition of nucleobase-specific oligonucleotide digestion depends on the hydration, localization of the substrates, and viscosity of the resultant co-assembly upon substrate binding with the enzyme-metallosurfactant complex. Additionally, through isothermal titration calorimetry experiment, we demonstrate enthalpy-entropy change during both the supramolecular binding of (oligo)nucleotides and simultaneous activation/inhibition in catalytic cleavage. Overall, it showed the possible modularity of Zn(II)-mediated biosupramolecular interaction, describing intrinsic thermodynamic aspects in developing complex biocatalytic circuits with nucleobase-specific oligonucleotides inputs, which are relevant in designing nucleic acid-based cargo for drug delivery and bioimaging.

A strategy for healthy eating habits of daily fruits revisited: A metabolomics study

Many people peel fruits, commonly persimmon, grape, apple, and peach, before eating as table fruits. Differences of bioactive compounds between peels and pulps of daily fruits are widely known but limited to individual compound because understanding of differences in their global metabolites is lack. We employed 1H NMR-based metabolomics to explore the global metabolite differences between their peels and pulps from the fruits, which included changes of diverse metabolites in persimmon after harvest ripening. Of diverse metabolites observed among the fruits tested, various health-beneficial metabolites were present in the peels rather than the pulps and their classes were dependent on the type of fruit: gallocatechin, epicatechin and epigallocatehin only in persimmon, apple, and peach, respectively; quercetin only in persimmon and apple; kaempferol only in persimmon; chlorogenic acid only in grape and peach; neochlorogenic acid only in apple and peach; p-coumaric acid only in grape; phloridzin and catechin only in apple. These metabolites in the peels of each fruits were strongly correlated with free radical-scavenging activity and delay of carbohydrate digestion. Therefore, intake of whole fruits, rather than removal of their peels, were recommended for potential improvement of healthy lifespan and human wellness. This study highlights the critical role of metabolomic studies in simultaneous determinations of diverse and intrinsic metabolites in different types of fruits and thus providing a strategy for healthy eating habits of daily fruits.

Effect of Gastrointestinal Digestion on the Bioaccessibility of Phenolic Compounds and Antioxidant Activity of Fermented Aloe vera Juices.

Plant-based beverages are enriched by the fermentation process. However, their biocompounds are transformed during gastrointestinal digestion, improving their bioaccessibility, which is of primary importance when considering the associated health benefits. This study aimed to evaluate the effect of in vitro gastrointestinal digestion on phenolic compound bioaccessibility and antioxidant activity of novel Aloe vera juices fermented by probiotic Enterococcus faecium and Lactococcus lactis. Aloe vera juices were digested using the standardized static INFOGEST protocol. During digestion, phenolic compounds and antioxidant activity (DPPH, ABTS, and FRAP) were accessed. The digestion process was seen to significantly increase the total phenolic content of the fermented Aloe vera juices. The fermentation of Aloe vera increased the bioaccessibility of juice biocompounds, particularly for kaempferol, ellagic acid, resveratrol, hesperidin, ferulic acid, and aloin. The phenolics released during digestion were able to reduce the oxidative radicals assessed by ABTS and FRAP tests, increasing the antioxidant action in the intestine, where they are absorbed. The fermentation of Aloe vera by probiotics is an excellent process to increase the bioavailability of beverages, resulting in natural added-value functional products.

Antibody-free photoelectrochemical strategy for simultaneous detection of methylated RNA, METTL3/METTL14 protein and MazF protein based on enhanced photoactivity of MoSe2–BiOI nanocomposite

Taking advantages of the catalytic activity of METTL3/METTL14 protein towards adenine methylation in RNA sequence and the specific digestion activity of MazF protein towards unmethylated RNA sequence containing ACA bases, a novel photoelectrochemical biosensor was constructed for simultaneous detection of RNA methylation, METTL3/METTL14 protein and MazF protein. MoSe2–BiOI nanocomposite was prepared and considered as photoactive material, catalytic hairpin assembly strategy and in situ generation of electron donors catalyzed by polyaspartic acid-loaded alkaline phosphatase technique were employed as signal amplification. Under the optimum conditions, the detection ranges of methylated RNA, METTL3/METTL14 protein and MazF protein were 0.001–50 nM, 0.001–25 ng/μL, and 0.001–10 U/mL, respectively. The corresponding detection limits were 0.46 pM, 0.51 pg/μL and 0.42 U/μL with S/N = 3. In addition, the effect of drugs and composite pollutants on the activities of MazF proteins was assessed, proving the applicability of the developed method in the field of drug screening for MazF-related diseases. Moreover, the effects of pollutants on the activity of METTL3/METTL14 were also preliminarily explored, providing new information on pathogenic mechanism of pollutants.

Isolation and Identification of Anti-Inflammatory Peptide from Goose Blood Hydrolysate to Ameliorate LPS-Mediated Inflammation and Oxidative Stress in RAW264.7 Macrophages.

This study was designed to isolate an anti-inflammatory activity oligopeptide from goose blood (GBP) for ameliorating LPS-mediated inflammation response and oxidative stress in RAW264.7 macrophages. In this study, GBP was isolated by tangential flow ultrafiltration system (TFUS) combined with size exclusion chromatography (SEC), ion exchange chromatography (IEC), and reversed-phase liquid chromatography (RP-LC), and then identified by liquid chromatography mass spectrometry (LC-MS/MS). The experiment results indicated that the amino acid sequence of oligopeptide with the best anti-inflammatory activity was IIe-Val-Tyr-Pro-Trp-Thr-Gln-Arg (IVYPWTQR), which had a molecular weight of 1062.5720 Da, and was derived from haemoglobin subunit beta OS in goose blood. In addition, IVYPWTQR was confirmed to have satisfactory stability and maintained high anti-inflammatory activity in a simulated gastrointestinal digestion. The mechanism by which the IVYPWTQR protected against LPS-mediated inflammation response was attributed to downregulating the TLR4/NF-kB/iNOS pathway. Moreover, IVYPWTQR ameliorated oxidative stress damage in inflammatory state was attributed to activating antioxidant defence system, which was regulated by Keap-1/NRF2/HO-1 signalling pathway for decreasing the accumulation of reactive oxide species (ROS). In summary, these results indicated GBP could serve as a potential functional factor for prevention and improvement of inflammation mediated by LPS and provided an affordable dietary intervention strategy to prevent inflammation.

Effects of titanium dioxide (TiO2)/activated carbon (AC) nanoparticle on the growth and immunity of the giant freshwater prawn, Macrobrachium rosenbergii: potential toxicological risks to the aquatic crustaceans.

Due to their unique physicochemical characteristics, nanomaterials exhibit many excellent properties and functions, leading to their applications in numerous fields. The large-scale production and widespread application of nanomaterials have inevitably resulted in their release into the environment, especially the water environment. Several studies have confirmed that exposure to nanomaterials can be toxic to aquatic organisms. However, few studies have focused on the effects of nanomaterial exposure on growth and immunity in crustaceans. In the present study, juvenile Macrobrachium rosenbergii were exposed to different concentrations of titanium dioxide (TiO2)/activated carbon (AC) composite nanomaterial (0.1 and 0.5mg/L) for 45days. The effects of nanoparticle exposure on digestion and antioxidant-related enzyme activities, as well as the expression of growth and immunity-related genes and signaling pathway, were evaluated. Our results show that in response to low concentration of TiO2/AC nanoparticle (0.1mg/L), most of the enzyme activities related to digestion and antioxidation (TPS, LPS, AMS, SOD, and CAT) were diminished. On the contrary, the GSH-Px activity increased under the 0.1mg/L group of TiO2/AC nanoparticle concentration. Additionally, the level of digestive and antioxidant enzyme activities we detected was increased when exposed to 0.5mg/L TiO2/AC nanoparticle. By comparison to the expression level of growth-related genes in the control group, MSTN, CaBP, E75, Raptor, EcR, and EGF were significantly inhibited at 0.1 and 0.5mg/L concentrations of TiO2/AC nanoparticle, whereas the expression level of genes (TLR, JAK, STAT, PPAF, ACP, and AKP) related to immunity was increased when exposed to different concentrations of TiO2/AC nanoparticle. Compared with the control group (0mg/L concentration), 5166 DEGs were identified in the TiO2/AC nanoparticle group, and a large number of DEGs were involved in molting, energy metabolism, stress tolerance, and germ cell development. Moreover, KEGG analysis revealed that many DEGs were assigned into signaling pathways related to metabolic growth and immune stress. These results showed that exposure to TiO2/AC nanoparticle will result in the changes of enzyme activity and routine mRNA expression, suggesting that TiO2/AC nanoparticle which existed in aquatic environment might affect the physiology of M. rosenbergii. This study will provide significant information for the evaluation of nanomaterial toxicity on aquatic crustaceans.

Effects of chickpea protein fractions on α-amylase activity in digestion

This study concerns the effects of endogenous proteins on starch digestion kinetics. It investigates the effects in chickpeas of hydrolysates released from the endogenous proteins albumin, globulin and glutelin on the in vitro activity of porcine pancreatic α-amylase (PPA) and on starch digestion. Using a docking simulation, potential proteinaceous α-amylase inhibitors (α-AIs) belonging to the small peptides of albumin, globulin and glutelin are identified and their binding mechanisms with PPA are explored. It was found that cooking and pepsin hydrolysis led to severe degradation of protein fractions, accompanied by the enrichment of small (<10 kDa) peptides, among which peptides <3 kDa exhibited strong inhibitory activity (up to 50%). Most of the active α-AIs were therefore considered to be found in the fractions <3 kDa, and were further characterized by mass spectrometry combined with in silico analysis. Docking results showed that glutelin could produce the most α-AIs (45 peptides), followed by globulin (41) and albumin (12). Among these, 71 peptides were predicted to exhibit a competitive or uncompetitive type of inhibition on PPA, whereas 6 peptides performed a noncompetitive inhibition. The competitive and uncompetitive α-AIs inhibited enzyme activity mainly by binding to a flexible loop and three major catalytic residues in PPA, and the latter by interacting with the non-catalytic regions of PPA. Different inhibition types therefore can together to hinder the formation of enzyme-starch complexes, so that PPA activity is inhibited and starch digestibility could be reduced. • Chickpea proteins reduce starch digestion rate, which is nutritionally advantageous. • Cooking and pepsin hydrolysis produced albumin-, globulin- and glutelin-peptides. • Peptides<3 kDa had the highest α-amylase inhibitory activity. • 77 peptides were predicted to be α-amylase inhibitors. • Inhibitors exhibited competitive, uncompetitive and noncompetitive inhibition.

The Effects of using Acid-Consuming Bacteria and Different Buffers with High Concentration Diets on In Vitro Digestion and Fermentation Activity of Anaerobic Bacteria and Fungi of Fattening Lambs Rumen

The Effects of using Acid-Consuming Bacteria and Different Buffers with High Concentration Diets on In Vitro Digestion and Fermentation Activity of Anaerobic Bacteria and Fungi of Fattening Lambs Rumen