Metabolite profiling of camel milk and the fermentation bacteria agent TR1 fermented two types of sour camel milk using LC-MS in relation to their probiotic potentials.

Camel milk is a nutrient-rich diet and fermentation affects its nutritional value and probiotic function. In this study, sour camel milk and oat jujube sour camel milk were prepared using fermentation bacteria agent TR1, and the metabolites of camel milk, sour camel milk and oat jujube sour camel milk were detected using a non-targeted metabolomics approach using liquid chromatography-mass spectrometry (LC-MS).The results showed that the partial least squares discriminant analysis (PLS-DA) with 100 % accuracy and good predictive power detected 343 components in positive ion mode and 220 components in negative ion mode. The differential metabolites were mainly organic acids, amino acids, esters, vitamins and other substances contained in camel milk.It showed that there were significant differences in the metabolites of camel milk, sour camel milk and oat jujube sour camel milk. Based on the pathway enrichment analysis of the three dairy products in the KEGG database, 12 metabolic pathways mainly involved in the positive ion mode and 20 metabolic pathways mainly involved in the negative ion mode were identified. The main biochemical metabolic pathways and signal transduction pathways of the differential metabolites of the three dairy products were obtained. This study provides theoretical support for improving the nutritional quality and probiotic function of camel milk and fermented camel milk products and provides a basis for the development of relevant processing technologies and products for camel milk and fermented camel milk.

Plasma proteins, circulating metabolites mediate causal inference studies on the effect of gut bacteria on the risk of osteoporosis development.

BACKGROUND: The role of gut bacteria in preventing and delaying osteoporosis has been studied. However, the causal relationship between gut bacteria, plasma proteins, circulating metabolites and osteoporosis (OP) risk has not been fully revealed. MATERIALS AND METHODS: In this study, a two-sample Mendelian randomization study (MR) approach was used to assess the causal associations between gut bacteria, plasma proteins and circulating metabolites, and osteoporosis risk using Genome Wide Association Study (GWAS) data from gut bacteria(n=8208), plasma proteins(n=2263), circulating metabolites (n=123), and osteoporosis (3203 cases and 16380452 controls). Inverse-variance weighted (IVW) was used as the main analytical method to estimate the MR causal effect and to perform directional sensitivity analysis of causality. Finally, the mediating effect values for the influence of gut flora on OP pathogenesis through circulating metabolites were calculated by univariate MR analysis, and multivariate MR analysis. Next, we evaluated the effect of Phosphatidylcholine on the osteogenic function of bone marrow mesenchymal stem cells (BMSCs) through relevant experiments, including Edu detection of cell proliferation, alkaline phosphatase (ALP) staining, Alizarin red staining to evaluate osteogenic function, qPCR and WB detection of osteogenic differentiation related gene expression. RESULTS: A total of 9 gut microbial taxa, 15 plasma proteins and eight circulating metabolites were analysed for significant causal associations with the development of OP. Significant causal effects of 7 on gut bacteria, plasma proteins and circulating metabolites were analysed by univariate MR analysis and these results were used as exposure factors for subsequent multivariate MR. Multivariate MR analyses yielded a significant effect of circulating metabolites Phosphatidylcholine and other cholines on OP (P<0.05). Further mediation effect analysis showed that the mediation effect of Bifidobacteriaceae affecting OP through the circulating metabolite Phosphatidylcholine and other cholines was -0.0224, with a 95 % confidence interval for the mediation effect that did not include 0, and the complete mediation effect was significant. Phosphatidylcholine can promote BMSCs proliferation and osteogenesis. CONCLUSION: Our study demonstrated significant causal associations of gut bacteria, plasma proteins and circulating metabolites on OP, and that Bifidobacteriaceae affect OP through the circulating metabolites Phosphatidylcholine and other cholines. Phosphatidylcholine affects the osteogenic ability of BMSCs. Further exploration of potential microbiota-associated mechanisms of bone metabolism may offer new avenues for osteoporosis prevention and treatment of osteoporosis.

An Enhanced Insect Pest Counter Based on Saliency Map and Improved Non-Maximum Suppression.

Accurately counting the number of insect pests from digital images captured on yellow sticky traps remains a challenge in the field of insect pest monitoring. In this study, we develop a new approach to counting the number of insect pests using a saliency map and improved non-maximum suppression. Specifically, as the background of a yellow sticky trap is simple and the insect pest object is small, we exploit a saliency map to construct a region proposal generator including saliency map building, activation region formation, background-foreground classifier, and tune-up boxes involved in region proposal generation. For each region proposal, a convolutional neural network (CNN) model is used to classify it as a specific insect pest class, resulting in detection bounding boxes. By considering the relationship between detection bounding boxes, we thus develop an improved non-maximum suppression to sophisticatedly handle the redundant detection bounding boxes and obtain the insect pest number through counting the handled detection bounding boxes, each of which covers one insect pest. As this insect pest counter may miscount insect pests that are close to each other, we further integrate the widely used Faster R-CNN with the mentioned insect pest counter to construct a dual-path network. Extensive experimental simulations show that the two proposed insect pest counters achieve significant improvement in terms of F1 score against the state-of-the-art object detectors as well as insect pest detection methods.

Antioxidant and antihypertensive effects of garlic protein and its hydrolysates and the related mechanism.

Garlic protein (GP) was enzymatically hydrolyzed using pepsin and trypsin followed by the evaluation of antioxidant and angiotensin-converting enzyme (ACE) inhibitory activities of GP and its hydrolysates. The antihypertensive effects of GP and its hydrolysates were determined in vivo. The results showed that GP and its hydrolysates namely GPH-P (pepsin) and GPH-T (trypsin) possessed appreciable antioxidant and ACE inhibitory activities. The ACE inhibitory activity of GP, GPH-T, and GPH-P was in consistent with their antioxidant activities. GP and its hydrolysates offered significant protective effects against H2 O2 -induced oxidative damage (p < .05). In addition, the administration of GP, GPH-T, and GPH-P reduced the blood pressure in hypertensive rats. The mechanism might be to reduce blood pressure by inhibiting the activity of ACE, reducing the formation of ACEII, and protecting the activity of bradykinin. This study suggested that GP might be utilized as a promising functional food as antioxidant and antihypertensive agents. PRACTICAL APPLICATIONS: Garlic (Allium sativum L.) is one of the oldest cultivated plants that belongs to the Liliaceae family and it has been used in cooking and medicinal applications. Large quantities of garlic residuals were produced with the development of the garlic essential oil industry. These residuals are highly rich in proteins and they can be used for the preparation of protein hydrolysates. Generally, hydrolysates are considered as a promising food supplement due to the enrichment of amino acids present in it. In this study, garlic proteins (GPs) and its hydrolysates retain effective antioxidant effects. They were found to reduce  the blood pressure and prevent oxidative stress induced by H2 O2 . The information from this study could be used to develop a new nutritional supplement from GP and its hydrolysates to treat hypertension as well as prevent oxidative damage.

Identification of Ellagitannins in the Unripe Fruit of Rubus Chingii Hu and Evaluation of its Potential Antidiabetic Activity.

As a functional food, the unripe fruits of Rubus chingii Hu have been widely used in China for thousands of years. Twenty-five major ellagitannins (ETs) were identified from the unripe fruits, and a novel ellagitannin, chingiitannin A (1), together with four other known ETs (2-5) were isolated and identified by HPLC-QTOF-MS/MS and 2D-NMR. Chingiitannin A showed the highest α-glucosidase and α-amylase inhibitory activities (IC50 2.89 and 4.52 µM, respectively), which occurred in a reversible and noncompetitive manner. Static quenching was indicated in a fluorescence quenching assay. Molecular docking results revealed that chingiitannin A interacted with the enzymes mainly by hydrogen bonding and was bound in the allosteric site. Chingiitannin A was nontoxic, and it increased the glucose uptake in L6 myotubes. The results suggested that the unripe fruits of Rubus chingii Hu are rich sources of ETs, and chingiitannin A might be a good candidate for functional foods or antidiabetic drugs.

Identification and antimicrobial activity evaluation of three peptides from laba garlic and the related mechanism.

Laba garlic is a traditional Chinese processed garlic (Allium sativum L.) with multiple health benefits. This study was aimed at isolating and identifying three antimicrobial peptide fractions from laba garlic using Sephadex chromatography, pre-HPLC and LC-MS/MS and investigating the potential antimicrobial mechanism. The sequences of the three peptides were demonstrated to be Tyr-Asn-His-Asn-Phe (YNHNF, F3-3-a), Trp-Pro-Thr-Ser-Phe-Thr (WPTSFT, F3-3-b) and Ala-Val-Asp-Arg-Ala-Val (AVDRAV, F3-3-c), respectively. F3-3-c showed the strongest anti-microbial effects among these three fractions and it could inhibit the mycelial growth of E. coli and S. aureus in vitro with a minimum inhibitory concentration (MIC) of 100 µM and exhibited negligible hemolytic activity. F3-3-c showed amphipathic properties with the presence of α-helix (25.8 ± 0.56%), ß-strands (19.7 ± 0.45%), turns (21.2 ± 0.78%) and unordered conformation (33.3 ± 1.09%). Treatment of F3-3-c resulted in a change in the morphology of the hyphae and the disruption of membrane integrity as shown by SEM and TEM analyses. These results suggested that the laba garlic peptide F3-3-c might be a promising candidate for antibiotics and related functional foods.

Effects of N-trans-feruloyltyramine isolated from laba garlic on antioxidant, cytotoxic activities and H2O2-induced oxidative damage in HepG2 and L02 cells.

Laba garlic is a kind of processed garlic products, it is the traditional Chinese food with a long history. In this study, the antitumor, antioxidant and cytotoxic properties of the blue pigment (BP) from Laba garlic were investigated. N-trans-feruloyltyramine (FLA) was isolated and identified from BP. The protective effects of FLA against H2O2-induced oxidative damages in L02 cells were also assessed. The apoptotic effects of FLA were detected by using flow cytometry analysis. Results showed that the tumor growth was significantly suppressed by BP (P<0.05). BP and FLA exhibited remarkable antioxidant activities. L02 cells pretreatment with FLA could significantly fight against the oxidative damage induced by H2O2, inhibit the morphological changes of mitochondria and maintain the integrity of mitochondria. FLA showed proliferation inhibition on HepG2 cells with IC50 value of 194 ±â€¯0.894 µM. After treatment of FLA (320 µM), the results of MTT assay on HepG2 and L02 cells indicated that FLA had selective cytotoxic effects. It suggested a new way of prevention and treatment of tumors and FLA might be a promising candidate in cancer therapy and functional foods.

Improvement of the alkali stability of Penicillium cyclopium lipase by error-prone PCR

BACKGROUND: Lipases are extensively exploited in lots of industrial fields; cold-adapted lipases with alkali-resistance are especially desired in detergent industry. Penicillium cyclopium lipase I (PCL) might be suitable for applications of detergent industry due to its high catalytic efficiency at low temperature and relatively good alkali stability. In this study, to better meet the requirements, the alkali stability of PCL was further improved via directed evolution with error-prone PCR. RESULTS: The mutant PCL (N157F) with an improved alkali stability was selected based on a high-throughput activity assay. After incubating at pH 11.0 for 120 min, N157F retained 70% of its initial activity, which was 23% higher than that of wild type PCL. Combined with the three-dimensional structure analysis, N157F exhibited an improved alkali stability under the high pH condition due to the interactions of hydrophilicity and ß-strand propensity. Conclusions: This work provided the theoretical foundation and preliminary data for improving alkali stability of PCL to meet the industrial requirements, which is also beneficial to improving alkali-tolerance ability of other industrial enzymes via molecular modification.

Structural characterization of corn silk polysaccharides and its effect in H2O2 induced oxidative damage in L6 skeletal muscle cells.

To evaluate the antioxidant activity of polysaccharides from corn silk in H2O2 induced oxidative damage in L6 skeletal muscle cells. A polysaccharide (CSP2) was isolated from corn silk. Structure analysis of CSP2 with 1D and 2D NMR indicated that CSP2 was composed of (1→6)-linked α-d-glucose. The substituent of the α-d-glucose is composed of (1→3)-linked α-l-arabinose, (1→4)-linked ß-d-galactose and (1→3,5)-linked ß-d-mannose, with ß-d-xylose and α-l-rhamnose as terminal unit. CSP2 had the potential to scavenge DPPH and hydroxyl radical and inhibit hemolysis in vitro. CSP2 was found to suppress oxidant stress by improving the enzyme activities of SOD, CAT, and GPX. Rodamine 123 staining results showed that the pretreatment of CSP2 prevented changes in the mitochondrial membrane potential and increased the fluorescence intensity in L6 cells in the presence of H2O2. These results suggested that CSP2 could be utilized as a potential antioxidant supplement to prevent oxidative stress.

Inhibitory effect of epigallocatechin-3-O-gallate on α-glucosidase and its hypoglycemic effect via targeting PI3K/AKT signaling pathway in L6 skeletal muscle cells.

Epigallocatechin-3-O-gallate (EGCG), a tea polyphenol is renowned for its anti-diabetic properties, however limited studies elucidate its hypoglycemic mechanism from multi-perspectives. In the present study, the interaction between EGCG and α-glucosidase was investigated through kinetics analysis, fluorescence spectra, Fourier transform infrared (FT-IR) spectra and molecular docking studies. Additionally, the effect of EGCG on glucose uptake and its related signaling pathway in L6 muscle cells were also investigated. The results showed that the α-glucosidase inhibitory activity of EGCG (IC50 = 19.5 ±â€¯0.3 µM) was higher than that acarbose (IC50 = 278.7 ±â€¯1.1 µM). EGCG inhibited α-glucosidase in a reversible and non-competitive manner. EGCG quenched the fluorescence of α-glucosidase due to the complex formation between EGCG and α-glucosidase, where the hydrogen bonds played a critical role. Microenvironment and the secondary structure of α-glucosidase were highly influenced by EGCG. Molecular docking results indicated that the binding sites on α-glucosidase for EGCG were close to the active site pocket of the enzyme. EGCG was also found to enhance the glucose uptake and promote GLUT4 translocation to plasma membrane via PI3K/AKT signaling pathway in L6 skeletal muscle cells. Overall, these results revealed the possible hypoglycemic mechanism of EGCG.

Hypoglycemic effects of polysaccharides from corn silk (Maydis stigma) and their beneficial roles via regulating the PI3K/Akt signaling pathway in L6 skeletal muscle myotubes.

In the present study, the physicochemical properties of polysaccharides from corn silk (CSP) with different molecular weights were characterized and their inhibitory actions against α-glucosidase and α-amylase were evaluated. Then their effects on glucose uptake and mechanism of action in PI3K/Akt signaling pathway were also determined in L6 skeletal muscle cells. Results demonstrated that CSP could significantly inhibit α-amylase and α-glucosidase. CSP were non-toxic and they considerably increased the 2-NBDG uptake (P < 0.05) in L6 cells. Additionally, CSP regulated the PI3K/Akt signaling pathway and promoted the translocation of GLUT4 to the plasma membrane that would enhanced the glucose uptake in rat L6 skeletal muscle cells. Among the tested polysaccharides, CSP2 with the molecular weight of 62.16 kDa exerted appreciable hypoglycemic activity. Altogether it was suggested that CSP could be the promising candidate in the treatment of Type 2 Diabetes Mellitus (T2DM). The elucidation of the potential anti-diabetic mechanism of the polysaccharides from corn silk will facilitate their utilization in the functional food industries.

Observing the effect of traditional Chinese medicine Kouchuang Xiaotong powder on patients with recurrent aphthus ulcer.

The effect of traditional Chinese medicine Kouchuang Xiaotong powder on patients with recurrent aphthous ulcer is observed and analyzed. 140 patients with recurrent aphthous ulcer in our hospital were selected as research objects, which were randomly divided into two groups: study group and control group. Among them, the patients in study group were treated with traditional Chinese medicine kouchuang xiaotong powder, and patients in control group were given the general routine treatment, comparing overall effective treatment of the two groups. Through comparing the time of pain disappearance, the size of ulcer after treatment, ulcer healing time and the time of feeding improvement, the results showed that study group had more obvious advantages than control group with P<0.05; through comparing pain score and overall curative effect of the two groups, study group was significantly superior than control group with P<0.05.The treatment of traditional Chinese medicine Kouchang Xiaotong powder on patients with recurrent aphthous ulcer, it can obtain good effect, significantly improve the curative effect and promote recovery as soon as possible.

Studies on the binding characteristics of three polysaccharides with different molecular weight and flavonoids from corn silk (Maydis stigma).

Polysaccharides and flavonoids co-existed in corn silk (Maydis stigma) could interact inevitably during processing and digestion. In this study, the binding interaction between three polysaccharides with different molecular weight and flavonoids from corn silk was characterized using molecular dynamic and thermodynamic simulation. And the corn silk polysaccharides-flavonoids complex (CSP - CSF complex) was characterized using fourier transform infrared (FT-IR) spectra, circular dichroism (CD), scanning electron microscope (SEM) and differential scanning calorimetry (DSC). The three polysaccharides from corn silk showed the molecular weight distributions of 43.3 kDa, 61.3 kDa and 106.6 kDa, respectively, and they had the same monosaccharide types with different ratios. The adsorption of flavonoids to polysaccharides might be mostly driven by van der Waals forces and hydrogen bonding, and it could be described through various isothermal models and thermodynamic equations such as Langmuir, Freundlich equations and Clausius-Clapeyron equation. This type of interactions could improve the biological activities of polysaccharides such as α-amylase and α-glucosidase inhibition.

Effect of different drying methods on the physicochemical properties and antioxidant activities of mulberry leaves polysaccharides.

This study aimed to optimize the suitable drying method to obtain high yield of polysaccharides from mulberry leaves and to determine their structural characterization and antioxidant activities. The effects of three different drying methods such as air dried, hot air dried (55 °C, 65 °C & 75 °C) and freeze dried on the physicochemical and antioxidant properties of mulberry leaves polysaccharides were studied using gas chromatography, high performance gel permeation chromatography, Fourier transform infrared spectroscopy, scanning electron micrography and antioxidant assays. Results revealed that pre-treatment remarkably influenced the changes in their physicochemical and antioxidant properties. In comparison with the other drying techniques, freeze dried polysaccharides showed more rough morphologies and significant antioxidant property. The yield of polysaccharides from the freeze dried sample was about 28.88% higher than the yield of hot air dried sample. The MDA activity of freeze dried sample was about 95.45%. Overall, the results suggested that the freeze drying technique was the appropriate method to extract polysaccharides from mulberry leaves that offered significant biological properties.

Preparation and characterization of a novel nanocomposite with double enzymes immobilized on magnetic Fe3O4-chitosan-sodium tripolyphosphate.

In this study, a novel and efficient synchronously immobilization of double enzymes (DE, alcalase and trypsin) were developed by using the chitosan and sodium tripolyphosphate-coated magnetic nanoparticles (Fe3O4@CS-TPP) as support. The physicochemical properties of DE-Fe3O4@CS-TPP NPs were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), transmission electron microscopy (TEM) and magnetic measurements. The preparation conditions and stabilities were also optimized and assessed. Results showed that the optimum preparation conditions were as follows: ratio of alcalase and trypsin of 3:1, enzyme concentration of 6% (w/w), temperature of 50 °C and pH of 9.0, the enzyme concentration absorbed by Fe3O4@CS-TPP NPs of 6 mg mL-1, immoblization time of 4 h, and glutaraldehyde content of 3% (w/w). The Km and Vmax values were determined as 0.5035 mg mL-1, 6.900 mg mL-1 min-1 for the immobilized enzymes, respectively. DE-Fe3O4@CS-TPP NPs was more stable than the free enzyme above 40 °C. The activity of DE-Fe3O4@CS-TPP NPs was preserved 86% after 35 days storage and retained more than 60% of its initial activity after ten times of successive reuse. Application of DE-Fe3O4@CS-TPP NPs in various protein hydrolysis showed favorable degrees of hydrolysis, yields and antioxidant activity. The results demonstrated that the DE-Fe3O4@CS-TPP NPs were suitable for application in food protein hydrolysis.

Physicochemical properties of polysaccharides from Lentinus edodes under high pressure cooking treatment and its enhanced anticancer effects.

This study was to investigate the physicochemical properties and anticancer effects of polysaccharides from Lentinus edodes extracted under high pressure cooking treatment (HPLPS) in vitro and in vivo. The extraction efficiency was improved. The main molecular weight of HPLPS was about 540 and about 227 kDa. And the inhibitory effects on HepG2 and HeLa cells of HPLPS were significantly increased (p < 0.05). The in vivo anticancer effect on H22 tumor bearing mice model was evaluated. The tumor growth inhibitory rate of HPLPS-H was 67.66%. The activities of ALT and AST were decreased. The activities of SOD, CAT, GSH-Px were notably increased. The expressions of IL-2 and TNF-α were increased while the expression of VEGF was decreased. These results suggested that high pressure-assisted extracted polysaccharides from Lentinus edodes might be effectively used for the treatment of hepatocellular carcinoma through its antioxidant and immunomodulatory effects.

[Research on Fenton treatment of the biochemical processes effluent of bamboo industry wastewater].

The decolorization and organic matter reduction of bamboo wastewater using Fenton oxidation was studied. Considering the cost and the removal efficiency, the optimal conditions were t = 30 degrees C, pH = 3.5, p(H2O2) = 1 665 mg x L(-1), c(Fe2+)/c(H2O2) = 0.072 and reaction time 3 h, with an initial COD and color concentration of wastewater of 430 mg x L(-1) and 1 500 times, under these conditions, the removal efficiency of COD and color could achieve 87.5% and 94.4%, respectively. It was found that the color reduction was higher than that of organics, and less affected by operation factors. The GC-MS analysis revealed that the chromophoric groups and auxochromic groups were greatly removed after Fenton treatment. The intermediates were mainly ester derivatives, and the by-products included 1-iodo-tridecane and 1,1'-oxybisoctane.