Zhao-Jun Wei

Anti-Cancerous Potential of Polysaccharide Fractions Extracted from Peony Seed Dreg on Various Human Cancer Cell Lines Via Cell Cycle Arrest and Apoptosis

In this study, four homo/heterogenous polysaccharides (HBSS, CHSS, DASS, and CASS) extracted from peony seed dreg with respective molecular weights of 3467, 4677, 229, and 56 kDa were evaluated for anti-cancerous attributes in prostate cancer cells (Pc-3), colon cancer cells (HCT-116), human breast cancer cells (MCF-7), cervical cancer (Hela cells) and human embryonic kidney 293 (HEK 293) cells as control. Among them, CASS and DASS extracted by alkali, consisted of 34.43% Gal, 26.39% Ara, 21.80% Glc and 35.77% Ara, 19.35% Gal, 17.77% Man, respectively. CASS fraction had the most significant inhibitory effects on all the cell lines used whereas HBSS had least effect. The CASS shown remarkable inhibition and cytotoxic effects in Hela cells followed by other cell lines as compared to 5-fluorouracil (5-FU). CASS arrested cell cycle in G0/G1 phase except MCF-7 cells and increased apoptotic cells percentage varied in different treated cells. CASS down regulated the expression of Cyclin A/B1/D1/E1, CDK-1/2/4/6 and p15/16/21/27 excluding p53. The notable change in expression of proteins (Cytochrome C, Bax, Bcl-2, p-Caspase-3, -8, -9, and PARP) was observed followed by Apaf-1 and Survivin. These findings indicated that CASS has an anti-cancerous potential in the treatment of human cancers which make it a potent candidate in functional foods.

Metabolic Effect of 1-Deoxynojirimycin from Mulberry Leaves on db/db Diabetic Mice Using Liquid Chromatography–Mass Spectrometry Based Metabolomics

Metabolomics was applied to the liquid chromatography-mass spectrometry urinary metabolic profile of type 2 diabetes (T2DM) mice treated with mulberry 1-deoxynojirimycin (DNJ). The serum biochemical indicators related to T2DM like blood glucose, insulin, triglyceride, total cholesterol, nitrogen, malondialdehyde, and creatinine decreased significantly in the treated group. The histopathological changes in liver cells were marked by deformations and disruptions in central area of nuclei in DM mice, whereas DNJ treatment recovered regular liver cells with normal nuclei. Most of the metabolites of T2DM were significantly different from healthy controls in the bulk data generated. The level of 16 metabolites showed that the diabetic group was closer to the healthy group as the DNJ treatment time prolonged. Moreover, DNJ inhibited the activity of glucosidase on glucose, lipid, and amino acid metabolism. Our results showed the mechanism of DNJ treatment of T2DM and could fetch deep insights into the potent metabolite markers of the applied antidiabetic interventions.

Antioxidant and antibacterial evaluation of polysaccharides sequentially extracted from onion ( Allium cepa L.)

We investigated the antioxidant and antimicrobial potential of sequentially extracted onion polysaccharide fractions namely HBSS, CHSS, DASS and CASS. The different antioxidant assays indicated that ACLPs exhibited potentially appreciable antioxidant activity in a dose-dependent manner. Among all the fractions, CHSS rendered the highest antioxidant action towards ABTS radical cations (97.52%), Fe2+ chelating (98.94%) and superoxide anion radical scavenging (76.27%). Whereas, HBSS possessed the highest potential for DPPH radicals (93.68%), hydroxyl radicals (65.12%) as well as for reducing power (0.559). CASS exhibited the highest lipid peroxidation inhibition (86.43%), while, DASS showed the best β-carotene bleaching inhibition (92.26%). Furthermore, regardless of the bacterial strain, DASS represented the strongest antibacterial activity on the basis of largest inhibition zone, the lowest minimal inhibitory concentration and maximum inhibition of bacterial growth in liquid medium. Overall results indicated that ACLPs hold a promise as potential natural antioxidant additives and antimicrobial agents for formulating the functional foods with potential applications in the medical and food industries.

Thermal and Antioxidant Properties of Polysaccharides Sequentially Extracted from Mulberry Leaves (Morus alba L.).

Polysaccharides from natural plant products are gaining considerable attention due to their multi-faceted health effects, as well their functional applications in food production. We reported the sequential extraction of mulberry leaf polysaccharides (MLPs) with hot buffer (HBSS), chelating agent (CHSS), dilute alkali (DASS) and concentrated alkali (CASS), in order to obtain polysaccharide fractions. Monosaccharide analysis proved that galactose (27.07%) and arabinose (25.99%) were the major sugars in HBSS, whereas arabinose (30.55%) was the major sugar in CHSS, and glucose was the major sugar in DASS (24.96%) and CASS (27.51%). The molecular weights of the polysaccharide fractions were 7.812 × 103 (HBSS), 3.279 × 103 (CHSS), 6.912 × 103 (DASS), and 1.408 × 103 kDa (CASS). HBSS and CASS showed the largest peak temperature and the highest endothermic enthalpy, respectively. Different antioxidant assays showed that the MLPs possessed appreciable antioxidant activities in a dose-dependent manner. At 5 mg/mL, HBSS and DASS possessed the largest 2,2-diphenyl-1-picryl-hydrazyl-hydrate (DPPH) radical scavenging activity (96.82%). HBSS exhibited the highest reducing power, and DASS rendered the strongest ABTS radical scavenging activity (99.69%). CHSS performed the best hydroxyl radical scavenging activity (64.22%) and Fe2+-chelating ability (96.36%). Our results suggested that MLPs could be a promising source of natural antioxidants for use in the food, pharmaceutical, and cosmetic industries.

Insights into physicochemical and functional properties of polysaccharides sequentially extracted from onion (Allium cepa L.)

Onion polysaccharides (ACLP) were sequentially extracted with four different solvents (hot buffer, chelating agent, dilute alkaline and concentrated alkaline) and obtained four fractions, named as HBSS, CHSS, DASS and CASS, respectively. The present studies characterized the ACLP concerning its physicochemical and functional properties. Monosaccharides analysis revealed that mannose (81.68%) was the dominant sugar in HBSS and galactose (67.59%) was the most in CASS. Similarly, CHSS and DASS possessed mannose and galactose as major sugar, which were 25.80% and 31.37%, 20.33% and 33.96%, respectively. The obtained molecular weight of ACLPs were 7.702×103 (HBSS), 4.690×103 (CHSS), 4.943×103 (DASS) and 1.390×103kDa (CASS). CASS resulted in the strongest solubility, fat-binding capacity, foam capacity and foam stability whereas, HBSS showed the highest thermal stability. DASS showed the best hygroscopicity and the best moisture retention was obtained by CHSS. Subsequently, the emulsifying activity and emulsifying stability were the highest for HBSS and the longest for of CASS, respectively. The rheological properties of CHSS exhibited the largest viscosity. Our results indicated that all factions could be considered as functional polysaccharides according to their respective characteristics, which have vast potential in food production.

Antioxidant and antimicrobial potential of polysaccharides sequentially extracted from Polygonatum cyrtonema Hua

We examined the antioxidant and antimicrobial attributes of Polygonatum cyrtonema Hua polysaccharides (HBSS, CHSS, DASS, CASS). The UV spectra and FT-IR results showed the purity and acidic nature of polysaccharides with β-configurations. DASS (78.585% hydroxyl radical scavenging, 92.794% ABTS radical scavenging, 75.648% DPPH radical scavenging activity, 0.582 reducing power and 98.721% Fe2+ chelation at 5mg/mL) possessed the best antioxidant potential; while, HBSS (21.113% hydroxyl radical scavenging, 14.412% ABTS radical scavenging, 28.005% DPPH radical scavenging activity, 0.285 reducing power and 48.969% Fe2+ chelation at 5mg/mL) was observed with the lowest antioxidant action. The bacterial inhibition effect of four PCHPs on Gram-positive organisms (B. subtilis and S. aureus with the maximum inhibitory diameters of 18.9 and 15.8mm, respectively) was better than that of Gram-negative bacteria (E. coli and S. typhimurium with the maximum inhibitory diameters of 10.9 and 8.4mm, respectively). The bacterial sensitivity was observed in the following order: B. subtilis>S. aureus>E. coli>S. typhimurium. The trend of antibacterial action of PCHPs was in following order: DASS>CHSS>CASS>HBSS. DASS can be considered as natural anti-oxidant as well as spoilage inhibitors to enhance the nutritive and functional values of various foods.

Effects of different chemical modifications on the antibacterial activities of polysaccharides sequentially extracted from peony seed dreg

Four types of sequentially extracted peony seed dreg polysaccharides (PSDPs) fractions were modified through sulfation, phosphorylation and carboxymethylation and studied for their in vitro antioxidant characteristics. The modified derivatives showed decreased sugar and protein content, while uronic acid content was elevated as compared to native (un-modified) polysaccharides. Further, modified derivatives shared the similar maximum absorption peaks indicating their homogeneous nature. The Fourier transform infrared (FTIR) spectra of sulfated, carboxymethylated and phosphorylated derivatives showed that hydroxyl groups were converted to OS, COO and POH bonds, respectively. The sulfated polysaccharides (S-PSDPs) displayed the highest reducing ability [S-CASS (1.854)], DPPH radical scavenging ability [S-CASS (95.07%)] and ABTS radical scavenging activity [S-CASS (99.85%)]. The phosphorylated polysaccharides (P-PSDPs) exhibited maximum hydroxyl radical scavenging activity [P-DASS (92.61%)] and ferrous ion chelating ability (99.94% for all the fractions). The carboxymethylated polysaccharides (C-PSDPs) maintained moderately stable antioxidant ability. Overall, the four different PSDPs modified by the same chemical method also resulted into different chemical composition, characteristic absorption peaks and antioxidant attributes. We conclude that the different modifications of the polysaccharide fractions had their own potential significance as new antioxidants for food industry and human health.

Development of a dynamic prediction model for shelf-life evaluation of yogurt by using physicochemical, microbiological and sensory parameters

ABSTRACT With the aim to develop a predictive model to quantify shelf-life of yogurt, two yogurt samples were stored at various temperatures (5–35°C) and targeted for sensory assessment and evaluated using physicochemical, microbiological and sensory analysis. An increase in acidity and reduction in three parameters were observed with storage time, but the changes exhibited were relatively small at 5°C compared with the variation at higher temperatures. Our study developed a dynamic prediction model to determine the shelf-life of yogurt. Because of relatively small influence on shelf-life, microbiological data were excluded; thus, shelf-life of this product was established only based on remaining parameters. The results showed that shelf-life prediction was 15.5 and 18.5 days for sample 1 and 2 at 5°C, respectively. The prediction had a minute difference with the marked shelf-life which recognized Arrhenius model as an effective tool to predetermine the shelf-life and to improve the quality management of yogurt product.

Isolation functional characterization of allatotropin receptor from the cotton bollworm, Helicoverpa armigera

Insect allatotropin (AT) plays multi-functions including regulation of juvenile hormone synthesis, growth, development and reproduction. In the present study, the full-length cDNA encoding the AT receptor was cloned from the brain of Helicoverpa armigera (Helar-ATR). The ORF of Helar-ATR exhibited the characteristic seven transmembrane domains of the G protein-coupled receptor (GPCR) and was close to the ATR of Manduca sexta in the phylogenetic tree. The Helar-ATR expressed in vertebrate cell lines can be activated by Helar-AT and each Helar-ATL in a dose-responsive manner, in the following order: Helar-ATLI > Helar-ATLII > Helar-AT > Helar-ATLIII. Helar-ATLI and Helar-ATLII represented the functional ligands to Helar-ATR in vitro, while Helar-AT and Helar-ATLIII behaved as partial agonists. The in vitro functional analysis suggested that the Helar-ATR signal was mainly coupled with elevated levels of Ca2+ and independent of cAMP levels. Helar-ATR mRNA in larvae showed the highest level in the brain, followed by the thorax ganglion, abdomen ganglion, fat body and midgut. Helar-ATR mRNA levels in the complex of the brain-thoracic-abdomen ganglion on the 2nd day of the larval stage and during later pupal stages were observed to be relatively higher than in the wandering and early pupal stages.

Identification and hydrolysis kinetic of a novel antioxidant peptide from pecan meal using Alcalase

In this study, the hydrolysis of a pecan protein isolate (PPI) with Alcalase was carried out to generate antioxidant peptides. We proposed a kinetic model to illustrate the enzymolysis process of PPI, which was found suitable for depiction of the kinetic behavior for PPI hydrolysis by Alcalase. The PPI hydrolysis products were gradually fractionated by ultrafiltration through cut-off membranes with molecular weights of 10, 5 and 3 kDa and their antioxidant activities were evaluated in vitro. Further, the strongest antioxidant fraction (<3 kDa) and novel antioxidative peptide were successfully purified. The amino acid sequence of the purified peptide was identified as LAYLQYTDFETR. The purified fraction exhibited appreciable scavenging activities on ABTS radical (67.67%), DPPH radical (56.25%) and hydroxyl radical (47.42%) at 0.1 mg/mL. The results suggested that this novel peptide may serve as a potential antioxidant and it should be evaluated for development of functional foods and pharmaceuticals products.