Effects of dietary supplementation with Ampelopsis grossedentata extract on production performance and body health of hens.

To investigate the potential of Ampelopsis grossedentata extract used as a feed additive, laying performance, egg quality, yolk cholesterol, plasma biochemical parameters, intestinal histology, and gut microbiota of hens (n = 60) were determined between basal diet (CK) and dietary supplementation with A. grossedentata extract (RT) for 11 weeks. The laying rate in RT group was 6.3 percentage points higher than in CK group together with feed conversion rate decreasing. Significant upregulation of immunoglobulin indexes and downregulation of lipid-related indexes in RT group were also found in comparison with CK group, suggesting that dietary supplementation with A. grossedentata extract benefited in immunity enhancing and blood-fat depressing. Meanwhile, the villus height in duodenum and villus height to crypt depth ratio in duodenum and jejunum of RT group were significantly higher than that of CK group, indicating that dietary supplementation with A. grossedentata extract facilitated nutrient adsorption via intestinal histology changing. Moreover, the richness, diversity, and composition of gut microbiota in RT group significantly altered with a comparison of CK group, including beneficial bacterium and pathogenic bacterium, revealing that dietary supplementation with A. grossedentata extract could modify gut microbiota communities to affect intestinal adsorption and pathogen invasion. In addition, the lipid metabolism-related insulin signing pathway was significantly enriched by gut microbiota in RT group, which were conducive to egg production elevation via facilitating blood lipid amelioration and insulin resistance alleviation. These results provided a basis for A. grossedentata extract served as a feed additive in the hen industry.

Direct from solid natural products to pure compounds in a single step: Coupling online extraction with high-speed counter-current chromatography.

Extraction is the most important step in the purification of bioactive compounds from natural products. This study introduces a simple online extraction strategy coupled with high-speed counter-current chromatography for efficient extraction and purification of bioactive components from solid natural products. For online extraction strategy, 1.0 g of ground Mangnolia officinalis or Piper nigrum was loaded into a guard column, which was then positioned on the manual injection valve instead of the sample loop. Bioactive components were directly extracted by the mobile phase of high-speed counter-current chromatography, and then transferred into high-speed counter-current chromatography for purification. In addition, the compatibility of the developed methodology for direct purification of bioactive components from fresh M. officinalis was successfully demonstrated. Obviously, in comparison with traditional offline heat-reflux extraction, online extraction avoided the instrument, time, solvent, and energy consumption, and purified two phenolic compounds (honokiol and magnolol) from M. officinalis and three alkaloids (piperyline, piperine, and piperanine) from P. nigrum with high extraction efficiency. The superiority of the developed methodology is to establish an easy, rapid, and efficient technique for the purification of a wide variety of bioactive components from solid natural products.

Magnetic Porous Molecularly Imprinted Polymers Based on Surface Precipitation Polymerization and Mesoporous SiO2 Layer as Sacrificial Support for Efficient and Selective Extraction and Determination of Chlorogenic Acid in Duzhong Brick Tea.

Magnetic porous molecularly imprinted polymers (MPMIPs) for rapid and efficient selective recognition of chlorogenic acid (CGA) were effectively prepared based on surface precipitation polymerization using CGA as template, 4-vinylpyridine (4-VP) as functional monomer, and mesoporous SiO2 (mSiO2) layer as sacrificial support. A computational simulation by evaluation of electronic binding energy is used to optimize the stoichiometric ratio between CGA and 4-VP (1:5), which reduced the duration of laboratory trials. The porous MIP shell and the rid of solid MIPs by magnet gave MPMIPs high binding capacity (42.22 mg/g) and fast kinetic binding (35 min). Adsorption behavior between CGA and MPMIPs followed Langmuir equation and pseudo-first-order reaction kinetics. Furthermore, the obtained MPMIPs as solid phase adsorbents coupled with high performance liquid chromatography (HPLC) were employed for selective extraction and determination of CGA (2.93 ± 0.11 mg/g) in Duzhong brick tea. The recoveries from 91.8% to 104.2%, and the limit of detection (LOD) at 0.8 µg/mL were obtained. The linear range (2.0⁻150.0 µg/mL) was wide with R² > 0.999. Overall, this study provided an efficient approach for fabrication of well-constructed MPMIPs for fast and selective recognition and determination of CGA from complex samples.

Online coupling solid-phase ligand-fishing with high-performance liquid chromatography-diode array detector-tandem mass spectrometry for rapid screening and identification of xanthine oxidase inhibitors in natural products.

Screening and analysis of bioactive compounds from natural products is challenging work due to their complexity. This study presents the first report on hyphenation of solid-phase ligand-fishing using immobilized xanthine oxidase microcolumn (IXOM) and high-performance liquid chromatography-diode array detector-tandem mass spectrometry (HPLC-DAD-MS/MS) for screening and identification of XO inhibitors from complex mixtures. Solid-phase ligand-fishing system was hyphenated with the HPLC system via four-port switching valve and a six-port injection valve as an interface for transferring effluents from IXOM to HPLC, and collecting chromatograms from LFMC (ligand-fishing microextraction column) and C18 column in a run by only one DAD. Mixtures containing allopurinol (positive control) and tryptophane (negative control) were analyzed in order to verify the specificity and reproducibility of the approach. Subsequently, the newly developed system was applied to screening and identification of XO inhibitors from L. macranthoides and its human microsomal metabolites. Six prototype compounds (3-caffeoylquinic acid, 5-caffeoylquinic acid, 4-caffeoylquinic acid, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid) and three metabolites (3-caffeoyl-epi-quinic acid, 5-caffeoyl-epi-quinic acid, 4-caffeoyl-epi-quinic acid) with XO binding affinities were identified. The XO inhibition activities of six prototype compounds were evaluated and confirmed using in vitro enzymatic assay. With the online system developed here, we present a feasible, selective, and effective strategy for rapid screening and identification of enzyme inhibitors from complex mixtures.

Preparation of magnetic dummy molecularly imprinted polymers for selective extraction and analysis of salicylic acid in Actinidia chinensis.

Compounds with strong intramolecular hydrogen bonds (e.g., salicylic acid) have weak intermolecular hydrogen bonding interactions between them and functional monomers in the imprinting process. Consequently, the corresponding molecularly imprinted polymers (MIPs) have no specific adsorption ability. Here, the first magnetic dummy MIPs (MDMIPs) based on benzonic acid as dummy template are successfully developed and evaluated with respect to the applications in selective enrichment and analysis of salicylic acid from complex mixtures. Various parameters affecting absorption/desorption were evaluated for achieving optimal recovery and reducing nonspecific interactions. The prepared MDMIPs showed high adsorption capacity, good selectivity, rapid kinetic binding (40 min) and magnetic separation (5 s), high reproducibility (RSD< 4 % for batch-to-batch evaluation), and stability (only 4 % decrease after 6 cycles). Owing to the efficacy in specific binding and removal of interference, trace level salicylic acid was quantified (0.2 µg/g of fresh mass) in Actinidia chinensis by high-performance liquid chromatography.

Comparative Analysis of the Effect of Dietary Supplementation with Fermented and Water-Extracted Leaf Extracts of Eucommia ulmoides on Egg Production and Egg Nutrition.

Although the water extract of Eucommia ulmoides leaf (WEE) promotes egg laying in hens, its palatability is poor. To improve the palatability of E. ulmoides leaf, probiotic fermentation was used, and fermented extract E. ulmoides leaf (FEE) was prepared using Lactiplantibacillus plantarum. The safety of FEE was investigated using a long-term toxicity test, and no oxidative damage, inflammatory reactions, or histological lesions were observed in the experimental rats receiving dietary supplementation of FEE at 200 mg/kg, suggesting that FEE is suitable for long-term feeding. Subsequently, dietary supplementation of FEE (group C) in comparison with dietary supplementation of WEE (group B), as well as a control (group A), was applied in the hen industry. Laying performance, egg quality, egg nutrition, egg flavor, and the gut microbiome were analyzed comparatively. Interestingly, the laying rate was observed to be four percentage points higher with dietary supplementation of FEE at 200 mg/kg compared with the control and two percentage points higher compared with the dietary addition of WEE at the same dosage. Simultaneously, a slight upregulation in daily feed consumption was determined in the FEE-supplemented group compared with the blank control and the WEE-supplemented group, indicating that the inclusion of FEE stimulated the hens' appetite. Moreover, variations in egg amino acids, fatty acids, and volatile components were obtained with either dietary addition, FEE or WEE, implying that dietary supplementation of the fermented and water-extracted E. ulmoides leaf extracts contributed to egg flavor change. Furthermore, variations in the gut microbiota were mediated by FEE, increasing the relative abundance of the genus Lactobacillus. These alterations in gut microbiota were tightly related to improved laying performance and egg flavor changes. Our results indicate that FEE is a better alternative feed additive in the hen industry than WEE.

Effect of dietary supplementation Ampelopsis grossedentata extract on growth performance and muscle nutrition of Megalobrama hoffmanni by gut bacterial mediation.

Nowadays, Megalobrama hoffmanni is a typical cultured fish in south China due to its resource decline in the Pearl River. Meanwhile, since antibiotics had been banned internationally, Chinese medical herbal plant serving as alternative to antibiotics has been adopted in aquaculture. In the present study, to ensure the health growth of M. hoffmanni, extract of traditional medical herbal plant Ampelopsis grossedentata was dietary supplemented and a series experiments were performed, including growth performance determination, physiological/biochemical detection, nutrition analysis, histology analysis, and 16S rRNA amplicon sequencing. Growth performance enhancement was determined since the weight gain rate (WGR), specific growth rate (SGR), and condition factor (CF) of M. hoffmanni increased as feeding inclusion A. grossedentata extract. Interestingly, the total content of muscle fatty acids ascended via supplementing A. grossedentata extract at middle level, in which group the activities of superoxide dismutase (SOD) and catalase (CAT) significantly increased and thus retarded the lipid peroxidation process (manifesting as malondialdehyde (MDA) content rising). Additionally, immune response and inflammatory reaction was stimulated in low and high level A. grossedentata extract added groups, indicating a suitable dosage of A. grossedentata extract benefited in safety production. Moreover, gut microbiota community varied hugely as daily supplementation A. grossedentata extract and the keystone species were tightly related to lipid transformation, which ultimately led to fatty acids composition variation. Our results confirmed that dietary supplementation A. grossedentata extract at the middle level (0.5‰, w/w) is suitable for serving as feed additive in healthful aquaculture of M. hoffmanni.

Combination of preparative HPLC and HSCCC methods to separate phosphodiesterase inhibitors from Eucommia ulmoides bark guided by ultrafiltration-based ligand screening.

Phosphodiesterase (PDE) inhibitors are widely used because of their various pharmacological properties, and natural products are considered the most productive source of PDE inhibitors. In this work, a new ultrafiltration-high-performance liquid chromatography (HPLC)-diode-array detection-mass spectrometry based ligand screening was developed for the first screening of PDE inhibitors from Eucommia ulmoides bark, and then the target bioactive compounds were prepared by combination of stepwise preparative HPLC and high-speed countercurrent chromatography (HSCCC) methods. Experiments were conducted to optimize the parameters in ultrafiltration, stepwise preparative HPLC, and HSCCC to allow rapid and effective screening and isolation of active compounds from complex mixtures. Seven lignans with purity over 97 % were isolated and identified by their UV, electrospray ionization mass spectrometry, and NMR data as (+)-pinoresinol-4,4'-di-O-ß-D-glucopyranoside (1), (+)-pinoresinol-4-O-ß-D-glucopyranosyl(1 → 6)-ß-D-glucopyranoside (2), (+)-medioresinol-4,4'-di-O-ß-D-glucopyranoside (3), (+)-syringaresinol-4,4'-di-O- ß-D-glucopyranoside (4), (-)-olivil-4'-O-ß-D-glucopyranoside (5), (-)-olivil-4-O-ß-D- glucopyranoside (6), and (+)-pinoresinol-4-O-ß-D-glucopyranoside (7). Compound 2 was first isolated from the genus Eucommia. Lignan diglucopyranosides (compounds 1-4) shower a greater inhibitory effect than lignan monoglucopyranosides (compounds 5-7). The method developed could be widely applied for high-throughput screening and preparative isolation of PDE inhibitors from natural products.

Effect of Fermented Artemisia argyi on Egg Quality, Nutrition, and Flavor by Gut Bacterial Mediation.

To improve the palatability of Artemisia argyi, fermented A. argyi (AAF) were prepared by Lactobacillus plantarum and Saccharomyces cerevisiae, which were used in the hen industry subsequently. Six hundred hens were randomly divided into three groups: control (A), dietary supplementation AAF at a low level (B), and dietary supplementation AAF at a high level (C). After feeding for four months, egg production, egg quality, egg nutrition, egg flavor, plasma biochemical parameters, intestinal histology, and microbiome of the gut contents were analyzed among the three tested groups. Interestingly, 5-6 percentage points elevation in the laying rates were observed in the AAF-supplemented groups in comparison to the control, accompanied with a 5 g increase in daily feed consumption. Since no alteration in egg/body weights was detected, laying performance enhancement was the main effect of dietary supplementation AAF. Meanwhile, the compositions of the egg amino acids and fatty acids changed as the feed inclusion AAF changed, e.g., His and linoleic acid decreased almost 0.1 and 0.5 g/100 g, respectively, while oleic acid increased almost 0.4 g/100 g. In addition, although no significant difference was detected (p > 0.05), the ß-diversity of the gut microbiota decreased as the diet addition of AAF decreased, and probiotics (Faecalibacterium, Prevotellaceae, Intestinimonas, and Lachnospiraceae) were the dominant keystone species under AAF treatments. These probiotics were well associated with the egg nutrition component variations based on the correlation analysis, as the Sankey plot showed. Furthermore, the results of headspace-gas chromatography-ion mobility spectrometry manifested that the egg volatile components varied (e.g., the contents of acetone, 4-methyl-3-penten-2-one, 1-hydroxy-2-propanone, ethyl acetate, ethyl octanoate, ethanol, and 2-butanol in the B and C groups were higher than in the A group) and separated clearly as daily supplementation AAF, indicating AAF hugely contributed to the egg flavor variation. Due to no significant differences noticed between the B and C groups, dietary supplementation AAF at a relative low level was enough to serve as a feed attractant in the hen industry for real feeding.

Comparative evaluation of three methods based on high-performance liquid chromatography analysis combined with a 2,2'-diphenyl-1-picrylhydrazyl assay for the rapid screening of antioxidants from Pueraria lobata flowers.

Traditional activity-guided fractionation of natural products is a time-consuming, labor intensive, and expensive strategy, which cannot compete with high-throughput and rapid screening of natural products. Therefore, more efficient approaches are necessary for searching active compounds from natural products. Three main methods based on high-performance liquid chromatography (HPLC) analysis combined with 2,2'-diphenyl-1-picrylhydrazyl (DPPH) assay, DPPH spiking HPLC analysis, on-line post-column HPLC-DPPH analysis, and HPLC-based DPPH activity profiling, were then developed for the rapid screening of antioxidants from complex mixtures. In the present study, a comparative study of these three methods has been conducted to identify antioxidants from an ethyl acetate fraction of Pueraria lobata flowers. The parameters in HPLC analysis and DPPH assay were optimized. The results indicated that all three methods could achieve similar information with regard to antioxidants, without the need for preparative isolation techniques. However, there were differences in instrumental set-up, sensitivity, and efficiency. DPPH spiking HPLC analysis seemed to be more sensitive and effective with simpler instrumental set-up and easier operation, which could also detect the total antioxidant capacity of color complexes. Eighteen antioxidants were tentatively screened and identified from P. lobata flowers by DPPH spiking HPLC-MS/MS. Among them, ten compounds including one new compound were first isolated from P. lobata flowers, and the DPPH radical scavenging activity of the new compound was reported for the first time.

Novel molecularly imprinted polymers based on multiwalled carbon nanotubes with bifunctional monomers for solid-phase extraction of rhein from the root of kiwi fruit.

A novel molecularly imprinted polymers based on multiwalled carbon nanotubes synthesized by precipitate polymerization was applied as a selective sorbent for separation and determination of rhein (4,5-dihydroxyanthraquinone-2-carboxylic acid) from the root of kiwi fruit samples coupled with high performance liquid chromatography (HPLC). The molecularly imprinted polymers were prepared with methacrylic acid and 4-vinylpyridine as bifunctional monomers. The chemical structure of the molecularly imprinted polymers was characterized by Fourier transform infrared spectrometer. The equilibrium rebinding experiment and competitive adsorption experiment showed that these imprinted polymers exhibited good adsorption ability toward rhein. The Langmuir adsorption equilibrium constant, K(m) , and theoretical maximum adsorption capacity, Q(m) , were estimated to be 0.43 and 6.77 mg g(-1) , respectively. Compared with molecularly imprinted polymers prepared with methacrylic acid or 4-vinylpyridine solely, the molecularly imprinted polymers synthesized with bifunctional monomers showed enhanced molecular imprinting effect and higher adsorption capacity for the template rhein. The performances of the molecularly imprinted polymers utilized as solid phase extraction sorbent were investigated in detail. The molecularly imprinted polymers prepared by the method proposed in this work could successfully apply to extraction and determination of rhein from the root of kiwi fruit samples coupled with HPLC.

Dietary supplementation Eucommia ulmoides extract at high content served as a feed additive in the hens industry.

Since numerous natural components in Eucommia ulmoides belong to phytoestrogen, its effect on hens production deserve more attention. To investigate the potential of E. ulmoides extract used as a feed additive, laying performance, egg quality, yolk cholesterol, yolk fatty acids, yolk fatty, yolk volatile components, albumen amino acids, plasma biochemical parameters, intestinal histology, and gut microbiota of hens (n = 120) were determined between basal diet (A) and dietary supplementation low (B), middle (C), and high (D) level E. ulmoides extract for 11 wk. When compared to A group, 2 percentage points elevation in laying rate was observed of D group. Significant up-regulation of immunoglobulin indexes and down-regulation of lipid related indexes in D group were also found if comparison with A group, suggesting that supplementation E. ulmoides extract at a relative high content benefited in immunity enhancing and blood-fat depressing. Meanwhile, obvious variation in albumen amino acids and yolk volatile compounds were inspected as dietary supplementation E. ulmoides extract, especially in D group, implied that the flavor of egg would change under high-level E. ulmoides extract treatment. Besides, villus height and villus height to crypt depth ratio of duodenum, jejunum, and ileum in D group were also significantly higher than that of in A group, indicating high-level E. ulmoides extract contributed to nutrient adsorption via intestinal histology changing. Moreover, the richness, diversity, and composition of gut microbiota in D group also significantly altered with a comparison of A group. These variation caused gut microbiota in D group major enriched in the KEGG pathway of insulin signing pathway, systemic lupus erythematosus, and bacterial invasion of epithelial cells, which were conducive to egg production elevation via facilitating nutrient adsorption, inflammation relieving, blood lipid amelioration, and insulin resistance alleviation. These results indicated that dietary supplementation E. ulmoides extract at high content could serve as a feed additive in the hens industry.

The effect of quercetin on diabetic nephropathy (DN): a systematic review and meta-analysis of animal studies.

Quercetin, a flavonoid possessing numerous biological activities, is reported to improve renal injury in diabetic animals. Here, the aim of this systematic review and meta-analysis is to assess the effect of quercetin on diabetic nephropathy and summarize its possible mechanisms. We searched in four databases PubMed, Web of Sciences (WOS), Cochrane and Embase from inception to May 2021 and ultimately included 20 animal studies in this review. A total of 12 outcome measurements including renal function indexes, oxidative stress biomarkers and inflammatory cytokines were extracted for meta-analysis using RevMan 5.4 software. Apart from creatinine clearance and uric acid with no significant difference, quercetin significantly decreased the levels of renal index, serum/plasma creatinine (SCr), blood urea nitrogen (BUN), urine protein, urine albumin, malondialdehyde (MDA), tumor necrosis factor (TNF)-α and interleukin (IL)-1ß, and increased superoxide dismutase (SOD) and catalase (CAT) activity. In short, quercetin improves renal function and attenuates the renal oxidative stress level and inflammatory response in DN animal models. Its possible action mechanisms include anti-oxidation, anti-inflammation, anti-fibrosis, and regulation of renal lipid accumulation.

Novel magnetic bovine serum albumin imprinted polymers with a matrix of carbon nanotubes, and their application to protein separation.

Novel magnetic multi-walled carbon nanotubes@Fe(3)O(4) molecularly imprinted polymers (MWNTs@Fe(3)O(4)-MIPs) intended for bovine serum albumin (BSA) recognition were successfully developed. The MWNTs@Fe(3)O(4)-MIPs were characterized with scanning electron microscopy (SEM) and Fourier transform infrared spectroscopy (FT-IR). Scanning electron microscopy images showed that the Fe(3)O(4) nanoparticles (diameter: 50-60 nm) were coated with a layer of MIPs with an average thickness of 25-30 nm. The magnetic material was easily dispersed and retrieved through the application of an external magnetic field. Adsorption experiments showed that the estimated maximum amount of BSA that could be adsorbed onto the MWNTs@Fe(3)O(4)-MIPs was 52.8 mg/g, and the time taken to reach equilibrium was about 40 min. Meanwhile, the MWNTs@Fe(3)O(4)-MIPs exhibited excellent selectivity towards (i.e., recognition of) BSA. The feasibility of the use of the MWNTs@Fe(3)O(4)-MIPs as a solid-phase extraction (SPE) sorbent was evaluated, and the results showed that the MWNTs@Fe(3)O(4)-MIPs were able to separate the template protein BSA from a binary protein solution. The proposed sorbent based on MWNTs@Fe(3)O(4)-MIPs for BSA separation exhibited satisfactory recoveries ranging from 92.0% to 97.3% in real samples. It was also successfully used for the purification of BSA from bovine calf serum.

Isolation of polyphenol compounds from olive waste and inhibition of their derivatives for α-glucosidase and α-amylase.

Olive waste was used as a sustainable resource because it contained a variety of valuable compounds. The polyphenols active fraction from enrichment by microporous resin and extraction with ethyl acetate were analysed by different chromatographic methods. A total of 14 polyphenolic compounds were isolated and identified by structure elucidation. Based on the above obtained compounds, tyrosol was selected as a characteristic polyphenol and participated in transesterification reaction to synthesise ß-ketoester using Yb(OTf)3. Then the Biginelli reaction with benzaldehyde, urea and ketoester (1:1.2:1.2) was performed at 90 °C for 3.0 h under the acidic condition. In addition, the ß-ketoester prepared using tyrosol with benzyl had a greater inhibitory effect on α-glucosidase and α-amylase, and the inhibition of enzyme activity for 3, 4-dihydropyrimidinone derivatives prepared using abovementioned ß-ketoester was improved significantly. Meanwhile, fluorine-containing dihydropyrimidinone derivatives were considerable inhibitors for both enzymes.

Adsorption and desorption characteristics of polyphenols from Eucommia ulmoides Oliv. leaves with macroporous resin and its inhibitory effect on α-amylase and α-glucosidase.

BACKGROUND: Eucommia ulmoides Oliv. (EUO) was a traditional Chinese herb, its leaves were abundant in China, and polyphenol compounds were considered to be an important active ingredient in Eucommia ulmoides Oliv. leaves (EUOL). However, previous research mainly focused on compound identification and extraction process, there were few reported on the efficient enrichment process and biological activity evaluation of polyphenols in EUOL. METHODS: The adsorption and desorption characteristics of twelve different resins (HPD-100, HPD-300, HPD-600, D-3250, X-5, D-140, NKA-9, NKA-II, D-101, AB-8, S-8 and Polyamide) were investigated to develop an efficient method for the enrichment of polyphenol from EUOL, and the static adsorption, kinetics, isotherm and thermodynamics of the polyphenol from EUOL were analyzed. The eluted component was obtained through dynamic elution, and its main polyphenol compounds were detected by high-phase liquid chromatography (HPLC) and the inhibitory effects on the enzyme activity of α-amylase and α-glucosidase was also evaluated for different elution components. Meanwhile, the binding of main polyphenol compounds to enzyme was also evaluated. RESULTS: The selected resins (HPD-300, HPD-600, D-3250, X-5, D-140, NKA-9, D-101 and AB-8) showed adsorption patterns that fitted well to the pseudo second-order kinetics. The intra-particle diffusion model demonstrated that the diffusion of polyphenol compounds on these resins were divided into three processes. For HPD-300, HPD-600 and NKA-9, the Freundlich model better described the adsorption isotherm behavior than the Langmuir model, and the adsorption of polyphenol was a physical, exothermic, and spontaneous process. Subsequently, dynamic elution was performed yielding a higher polyphenol content in a 60% ethanol-water elution component, and it also exhibited a higher inhibitory effect on α-amylase and α-glucosidase activity. Furthermore, as the main polyphenol compounds, chlorogenic acid, rutin, quercetin and kaempferol were used to simulate the binding to the enzyme protein through molecular docking technology. The results showed that quercetin had a higher docking score for α-amylase, while rutin displayed superior binding to α-glucosidase. CONCLUSIONS: Therefore, polyphenols of EUOL could be enriched through macroporous resins and have the potential to be effective enzyme inhibitor.

[Extraction and separation of flavonoids from leave of Eucommia ulmoides in aqueous two-phase system].

OBJECTIVE: To optimize the aqueous two-phase extraction and separation technology of flavonoids from the leaves of Eucommia ulmoides. METHODS: The system was prepared by dissolving suitable amounis of polyethylene glycol 4000 (PEG4000) and dextran 40000 ( D40) in aqueous solution. Phase map of the system, the mass fraction of PEG4000 and D40, the effects of amount of added sample, pH value and temperature on target compounds were investigated systematically. RESULTS: The optimum extraction conditions were PEG4000 11%, N40 8%, 8 g sample which contains 6.85% of flavonoids, temperature 60 t and pH value 8. The highest extraction rate could reach to 75.82%. CONCLUSION: This method has the advantages of mild conditions, solvent-free residues and less time-consumed, and the obvious efficiency in single-stage separation and purification of flavonoids.

Molecularly Imprinted Polymers-Coated CdTe Quantum Dots for Highly Sensitive and Selective Fluorescent Determination of Ferulic Acid.

Ferulic acid (FA), an important phenolic acid, is widely distributed in higher plants and presents many pharmacological effects. Therefore, sensitive determination of FA in complex matrix is necessary. Molecularly imprinted polymers-coated CdTe quantum dots (CdTe-QDs@MIPs) exhibited incomparable advantages because of their combination of excellent selectivity of MIPs and high sensitivity of QDs. Here, a fluorescent probe based on CdTe-QDs@MIPs was successfully fabricated for selective and sensitive determination of FA. MIPs shell was obtained by the reverse microemulsion method using FA, 3-(aminopropyl) triethoxysilane (APTES), and tetraethyl orthosilicate (TEOS), as template, functional monomer, and crosslinker. In optimal conditions, the fluorescence CdTe-QDs@MIPs sensor exhibited fast response (within only 3 min), high sensitivity (limit of detection, LOD at 0.85 µg/l), excellent linear ranges (2-100 µg/l) with a correlation coefficient of 0.9996, and distinguished selectivity for FA. Satisfactory recoveries from 91.8% to 110.3% were achieved with precisions below 6.6% for FA analysis in real pineapple juice and apple juice by developed CdTe-QDs@MIPs. The fluorescence results coincided well with those obtained by high-performance liquid chromatography (HPLC). It could be concluded that the resultant CdTe-QDs@MIPs offered a new way for rapid and sensitive analysis of FA in the complex matrix.

Online extraction-HPLC-FRAP system for direct identification of antioxidants from solid Du-zhong brick tea.

Du-zhong brick tea (DBT), a new post-fermented functional tea, is marketed in China for its prevention of diseases from oxidative stress. However, antioxidant compounds in DBT are not clear. Here, a novel online extraction-HPLC-ferric reducing antioxidant power (OLE-HPLC-FRAP) has been developed to screen antioxidants in DBT. For OLE, guard column is packed with DBT (1.0 mg), then compounds are extracted directly by HPLC mobile phase for HPLC-FRAP analysis without sample pretreatment procedures. Eleven antioxidants have been screened and identified, three of which are detected in Du-zhong for the first time. Contributions of eleven antioxidant compounds to total antioxidant activity are evaluated using chlorogenic acid as antioxidant marker. Results indicate that the developed OLE-HPLC-FRAP system is a simple and powerful tool to analyze antioxidant compounds from solid complex mixtures, which also contribute to the enhancement of the value of DBT as a good functional tea.

Dietary supplementation with the extract from Eucommia ulmoides leaves changed epithelial restitution and gut microbial community and composition of weanling piglets.

This study was conducted to compare the effects of Eucommia ulmoides leaves (EL) in different forms (EL extract, fermented EL, and EL powder) with antibiotics on growth performance, intestinal morphology, and the microbiota composition and diversity of weanling piglets. Compared to the control group, the antibiotics and EL extract significantly increased the average daily gain and decreased the feed: gain ratio as well as the diarrhea rate (P < 0.05). The EL extract significantly decreased the crypt depth and increased the ratio of villus height to crypt depth (P < 0.05), while the fermented EL group did the opposite (P < 0.05). The crypt depth in the antibiotics group was of similar value to the EL extract group, and was lower than the fermented EL and EL powder groups (P < 0.05). Compared to the control and antibiotics groups, the jejunul claudin-3 mRNA expression and the concentrations of total VFA, Chao 1, and ACE were significantly augmented in the EL extract group of piglets (P < 0.05). The EL extract groups also showed elevated Shannon (P < 0.05) and Simpson (P = 0.07) values relative to the control and antibiotics groups. At the phylum level, the EL extract group exhibited a reduced abundance of Bacteroidetes and an enhanced abundance of Firmicutes. At the genus level, the abundance of Prevotella was augmented in the EL extract group. Moreover, compared with the antibiotic group, the acetate concentration was enhanced in the EL extract and fermented EL groups. Overall, dietary supplementation with the EL extract, but not the fermented EL or EL powder, improved growth performance, jejunul morphology and function, as well as changed colonic microbial composition and diversity, which might be an alternative to confer protection against weanling stress in weanling piglets.