Exopolysaccharides of Paenibacillus polymyxa: A review.

Paenibacillus polymyxa (P. polymyxa) is a member of the genus Paenibacillus, which is a rod-shaped, spore-forming gram-positive bacterium. P. polymyxa is a source of many metabolically active substances, including polypeptides, volatile organic compounds, phytohormone, hydrolytic enzymes, exopolysaccharide (EPS), etc. Due to the wide range of compounds that it produces, P. polymyxa has been extensively studied as a plant growth promoting bacterium which provides a direct benefit to plants through the improvement of N fixation from the atmosphere and enhancement of the solubilization of phosphorus and the uptake of iron in the soil, and phytohormones production. Among the metabolites from P. polymyxa, EPS exhibits many activities, for example, antioxidant, immunomodulating, anti-tumor and many others. EPS has various applications in food, agriculture, environmental protection. Particularly, in the field of sustainable agriculture, P. polymyxa EPS can be served as a biofilm to colonize microbes, and also can act as a nutrient sink on the roots of plants in the rhizosphere. Therefore, this paper would provide a comprehensive review of the advancements of diverse aspects of EPS from P. polymyxa, including the production, extraction, structure, biosynthesis, bioactivity and applications, etc. It would provide a direction for future research on P. polymyxa EPS.

Calcium Enrichment in Edible Mushrooms: A Review.

Calcium is one of the essential minerals that enhances various biological activities, including the regulation of blood pressure, the prevention of osteoporosis and colorectal adenomas. Calcium-enriched edible mushrooms can be considered as one of the important daily sources of calcium in foods. Calcium accumulation in edible mushrooms is an effective way to enhance its activities because the organic state of calcium metabolites in edible mushrooms can be formed from the original inorganic calcium. The main calcium sources for calcium-enriched edible mushrooms' cultivation are CaCO3, CaCl2 or Ca(NO3)2. The growth and metabolic process of edible mushrooms are significantly influenced by calcium enrichment. Generally, Ca at low levels is good for the production of edible mushrooms, whereas the reverse phenomenon for the growth of edible mushrooms at high Ca contents is observed. In addition, metabolites, for example, phenolics, flavonoids, polysaccharides, enzymes, minerals, etc., are improved when edible mushrooms are enriched at a moderate level of calcium. This review summarized the literature regarding the influence of calcium enrichment on edible mushrooms' growth and major metabolites. Furthermore, the mechanisms of calcium enrichment in edible mushrooms were highlighted. Understanding calcium-enriched mechanisms in edible mushrooms would not only be beneficial to manipulate the cultivation of edible mushrooms having excellent biological activities and high levels of active Ca, but it would also contribute to the applications of calcium enrichment products in food industries.

[Effects of cultivated Cordyceps sinensis on proliferation and apoptosis of human leukemia K562 cells].

The present study was designed to investigate the effect of cultivated Cordyceps sinensis (CCS) on leukemia-derived K562 cells, and further explore the underlying mechanisms. After routine culture of K562 cells, MTT assay was used to detect the effect of CCS on survivel of human leukemia cell lines K562;DAPI staining was used to observe the morphological changes of the nucleus and AO/EB staining was used to observe cell apoptosis. JC-1 staining was employed to detect the changes in mitochondrial membrane potential. Flow cytometry (FCM) was used to detect cell cycle distribution, and Western blot analysis was used to detect the expression levels of Bax, Bcl-2, caspase 3, caspase 8, cyclin D1, CDK2, and CDK4 in K562 cells. The results showed that CCS (0.345-5.524 g·L⁻¹) substantially suppressed proliferation of K562 cells and induced G1/S phase arrest in a dose-dependent manner. DAPI and AO/EB staining indicated that cell apoptosis was significantly induced by CCS treatment, accompanied by decreased mitochondrial membrane potential demonstrated by JC-1 staining. Western blot results showed that CCS significantly increased the expression of Bax and, meanwhile, decreased the expression levels of Bcl-2, cyclin D1, CDK2, CDK4, caspase 3 and caspase 8. Collectively, our data demonstrated that CCS dose-dependently suppressed cell proliferation and induced cell apoptosis in K562 cells, and the mechanism might be associated with inducing cell cycle arrest, regulating Bcl-2/Bax ratio and activating the mitochondrial apoptosis pathway.

Optimization of microwave-assisted extraction of polyphenols from apple pomace using response surface methodology and HPLC analysis.

A simple and efficient microwave-assisted extraction of polyphenols from industrial apple pomace was developed and optimized by the maximization of the yield using response surface methodology. A Box-Behnken design was used to monitor the effect of microwave power, extraction time, ethanol concentration and ratio of solvent to raw material (g/mL) on the polyphenols yield. The results showed that the optimal conditions were as follows: microwave power 650.4 W, extraction time 53.7 s, ethanol concentration 62.1% and ratio of solvent to raw material 22.9:1. Validation tests indicated that the actual yield of polyphenols was 62.68±0.35 mg gallic acid equivalents per 100 g dry apple pomace with RSD=0.86% (n=5) under the optimal conditions, which was in good agreement with the predicted yield and higher than those of reflux and ultrasonic-assisted extraction methods. HPLC analysis indicated that the major polyphenols of apple pomace consisted of chlorogenic acid, caffeic acid, syrigin, procyanidin B2, (-)-epicatechin, cinnamic acid, coumaric acid, phlorizin and quercetin, of which procyanidin B2 had the highest content of 219.4 mg/kg.

Bis[4-(2-benzoyl-1-oxidoethen-yl)-3-hy-droxy-phenyl benzoato]diethano-l-cobalt(II).

In the title complex, [Co(C(22)H(15)O(5))(2)(C(2)H(5)OH)(2)], the Co(II) atom (site symmetry ) is coordinated by two O,O'-bidentate 4-(2-benzoyl-1-oxidoethen-yl)-3-hy-droxy-phenyl benzoate anions and two ethanol O atoms, resulting in a slightly distorted CoO(6) octa-hedral coordination. An intra-molecular O-H⋯O hydrogen bond in the ligand generates an S(6) ring. The dihedral angle between the aromatic rings joined to the acetyl-acetonate unit is 6.4 (2)°. The ethanol mol-ecule is disordered over two orientations in a 0.65 (3):0.35 (3) ratio. In the crystal, mol-ecules are linked by O-H⋯O bonds.

[Combined effect of cosolvent and cyclodextrin on solubilization of insoluble drugs].

AIM: To investigate the combined effect of cosolvent and cyclodextrin (CD) on solubilization of insoluble drugs. METHODS: Phase-solubility method was applied to determine solubilization of two diterpenoids in cosolvent / cyclodextrin combinations. The combined effect was evaluated and explained with an established mathematical model, and the model parameters were calculated by means of nonlinear regression analysis. RESULTS: The strong agreement between the predicted and the observed solubility data supports the validity of the proposed model, with the determination coefficients of two regression models were 0.993 and 0.992, separately. CONCLUSION: The validated mathematical model can be used to explain and predict the combined solubilization of the two insoluble drugs in different cosolvent systems.

[Cloning and identification of ROP2 gene of Toxoplasma gondii].

OBJECTIVE: To amplify ROP2 from the genomic DNA of Toxoplasma gondii RH strain and construct eukaryotic expression plasmid pc-DNA3-ROP2. METHODS: Tachyzoites of T. gondii RH strain were collected and depurated to obtain genome. A pair of primers was designed and synthesized according ROP2 gene sequence. The gene fragment encoding ROP2 was amplified from the genomic DNA of T. gondii RH strain by means of PCR. It was then reclaimed and purified, and inserted into cloning vector pUCm-T. The recon was cut by EcoR I, Hind III, and the inserted ROP2 gene fragment was subcloned into pc-DNA3 eukaryotic expression vector using T4DNA ligase, followed by further PCR identification, double digestion via restrictive enzymes, and sequencing. RESULTS: The amplified specific gene fragment of ROP2 was about 1.7 kb in length. The gene fragment cloned and subcloned into pc-DNA3 was correct, and the eukaryotic expression plasmid contained ROP2 gene fragment was successfully constructed. CONCLUSION: The recombinant plasmid pc-DNA3-ROP2 was successfully constructed.

[Studies on the immuno-protection of ROP2 nuclei acid vaccine in Toxoplasma gondii infection].

OBJECTIVE: To study the protective effect of ROP2 nuclei acid vaccine in mice. METHODS: Forty-two BALB/c mice were divided into three groups. Each mouse in experiment group was injected with 50 microg recombinant plasmid pc-DNA3-ROP2 through musculus quadriceps fexoris. In control groups, each mouse was injected with 50 microg blank plasmid pc-DNA3 and with 50 microl PBS respectively. All mice were immunized for three times with an interval of three weeks. The volume was doubled for the final injection in the two plasmid groups. Blood, spleens and lymph nodes of 4 mice in each group were taken for the detection of CD4+, CD8+ T cells and cytokines 2 weeks after the final immunization. The rest mice in 3 groups were challenged with 500 tachyzoites of Toxoplasm gondii RH strain for further observation. RESULTS: The vaccine induced strong cellular and humoral immune response. The titer of antibody in serum was high after inoculation and recognized ROP2 protein antigen expressed in vitro. The lymphocyte phenotype was analyzed. CD4+ T cells proliferated sharply (69.5+/-3.4)%, and the ratio of CD4/CD8+ increased considerably by (4.69+/-1.32)% (P<0.01). The level of IL-2, IL4, IL-6, IL-12, IFN-gamma and TNF in serum and cultured supernatant of spleen cells and lymph cells was higher in the experiment group than that in control groups, especially in serum. 88.9% mice in the experiment group were protected 180 hours after the challenge of T. gondii. The death time of mice in experiment group was delayed and the survival time was prolonged in comparison to that in control groups with a significant difference (P< 0.01). CONCLUSION: The recombinant ROP2 nuclei acid vaccine shows fair immunogeni-city and obviously produces immuno-protection.

Protective effect of Weikang decoction and partial ingredients on model rat with gastric mucosa ulcer.

AIM: To investigate the protective mechanisms of Weikang (WK) decoction on gastric mucosae. METHODS: Ninety rats were randomly divided into nine groups of 10 each, namely group, model group, group with large WK dosage, group with medium WK dosage, group with small WK dosage, group with herbs of jianpiyiqi (strengthening the spleen and replenishing qi), group with herbs of yangxuehuoxue (invigorating the circulation of and nourishing the blood), group with herbs of qingrejiedu (clearing away the heat-evils and toxic materials), group with colloidal bismuth pectin (CBP) capsules. According to the method adopted by Yang Xuesong, except normal control group, chronic gastric ulcer was induced with 100% acetic acid. On the sixth day after moldmaking, WK decoction was administered, respectively at doses of 20, 10 and 5 g/kg to rats of the WK groups, or the groups with herbs of jianpiyiqi, yangxuehuoxue and qingrejiedu, 10 mL/kg was separately administered to each group every day. For the group with CBP capsules, medicine was dissolved with water and doses 15 times of human therapeutic dose were administered (10 mL/kg solution containing 0.35% CBP). Rats of other groups were fed with physiological saline (10 mL/kg every day). Administration lasted for 16 d. Rats were killed on d 22 after mold making to observe changes of gastric mucosa. The mucus thickness of gastric mucosa surface was measured. Levels of epidermal growth factor (EGF) in gastric juice, nitric oxide (NO) in gastric tissue, endothelin (ET) in plasma, superoxide dismutase (SOD) in plasma, malondialdehyde (MDA) in plasma and prostaglandin I(2) (PGI(2)) were examined. RESULTS: Compared with control group, ulceration was found in gastric mucosa of model group rats. The mucus thickness of gastric mucosa surface, the levels of EGF, NO, 6-K-PGF(1)alpha and SOD decreased significantly in the model group (EGF: 0.818+/-0.18 vs 2.168+/-0.375, NO: 0.213+/-0.049 vs 0.601+/-0.081, 6-K-PGF(1)alpha: 59.7+/-6.3 vs 96.6+/-8.30, SOD: 128.6+/-15.0 vs 196.6+/-35.3, P<0.01), the levels of ET (179.96+/-37.40 vs 46.64+/-21.20, P<0.01) and MDA (48.2+/-4.5 vs 15.7+/-4.8, P<0.01) increased. Compared with model group, the thickness of regenerative mucosa increased, glandular arrangement was in order, and cystic dilative glands decreased, while the mucus thickness of gastric mucosa surface increased (20 g/kg WK: 51.3+/-2.9 vs 23.2+/-8.4, 10 g/kg WK: 43.3+/-2.9 vs 23.2+/-8.4, 5 g/kg WK: 36.1+/-7.2 vs 23.2+/-8.4, jianpiyiqi: 35.4+/-5.6 vs 23.2+/-8.4, yangxuehuoxue: 33.1+/-8.9 vs 23.2+/-8.4, qingrejiedu: 31.0+/-8.0 vs 23.2+/-8.4 and CBP: 38.2+/-3.5 vs 23.2+/-8.4, P<0.05-0.01). The levels of EGF (20 g/kg WK: 1.364+/-0.12 vs 0.818+/-0.18, 10 g/kg WK: 1.359+/-0.24 vs 0.818+/-0.18, 5 g/kg WK: 1.245+/-0.31 vs 0.818+/-0.18, jianpiyiqi: 1.025+/- 0.45 vs 0.818+/-0.18, yangxuehuoxue: 1.03+/-0.29 vs 0.818+/-0.18, qingrejiedu: 1.02+/-0.47 vs 0.818+/-0.18 and CBP: 1.237+/-0.20 vs 0.818+/-0.18, P<0.05-0.01), NO (20 g/kg WK: 0.480+/-0.026 vs 0.213+/-0.049, 10 g/kg WK: 0.390+/-0.055 vs 0.213+/-0.049, 5 g/kg WK: 0.394+/-0.026 vs 0.213+/-0.049, jianpiyiqi: 0.393+/-0.123 vs 0.213+/-0.049, yangxuehuoxue: 0.463+/-0.077 vs 0.213+/-0.049, qingrejiedu: 0.382+/-0.082 vs 0.213+/-0.049 and CBP: 0.395+/-0.053 vs 0.213+/-0.049, P<0.05-0.01), 6-K-PGF(1)alpha (20 g/kg WK: 86.8+/-7.6 vs 59.7+/-6.3, 10 g/kg WK: 77.9+/-7.0 vs 59.7+/-6.3, 5 g/kg WK: 70.0+/-5.4 vs 59.7+/-6.3, jianpiyiqi: 73.5+/-12.2 vs 59.7+/-6.3, yangxuehuoxue: 65.1+/-5.3 vs 59.7+/-6.3, qingrejiedu: 76.9+/-14.6 vs 59.7+/-6.3, and CBP: 93.7+/-10.7 vs 59.7+/-6.3, P<0.05-0.01) and SOD (20 g/kg WK: 186.4+/-19.9 vs 128.6+/-15.0, 10 g/kg WK: 168.2+/-21.7 vs 128.6+/-15.0, 5 g/kg WK: 155.6+/-21.6 vs 128.6+/-15.0, jianpiyiqi: 168.0+/-85.3 vs 128.6+/-15.0, yangxuehuoxue: 165.0+/-34.0 vs 128.6+/-15.0, qingrejiedu: 168.2+/-24.9 vs 128.6+/-15.0, and CBP: 156.3+/-18.1 vs 128.6+/-15.0, P<0.05-0.01) significantly increased. The levels of ET (20 g/kg WK: 81.30+/-17.20 vs 179.96+/-37.40, 10 g/kg WK: 83.40+/-25.90 vs 179.96+/-37.40, 5 g/kg WK: 93.87+/-20.70 vs 179.96+/-37.40, jianpiyiqi: 130.67+/-43.66 vs 179.96+/-37.40, yangxuehuoxue: 115.88+/-34.09 vs 179.96+/-37.40, qingrejiedu: 108.22+/-36.97 vs 179.96+/-37.40, and CBP: 91.96+/-19.0 vs 179.96+/-37.40, P<0.01) and MDA (20 g/kg WK: 21.6+/-7.4 vs 48.2+/-4.5, 10 g/kg WK: 32.2+/-7.3 vs 48.2+/-4.5, 5 g/kg WK: 34.2+/-6.2 vs 48.2+/-4.5, jianpiyiqi: 34.9+/-13.8 vs 48.2+/-4.5, yangxuehuoxue: 35.5+/-16.7 vs 48.2+/-4.5, qingrejiedu: 42.2+/-17.6 vs 48.2+/-4.5, and CBP: 30.1+/-6.1 vs 48.2+/-4.5, P<0.05-0.01) obviously decreased. The 20 g/kg WK group was better than 10 g/kg (the mucus thickness: 51.3+/-2.9 vs 43.3+/-2.9, NO: 0.480+/-0.026 vs 0.390+/-0.055, SOD: 186.4+/-19.9 vs 168.2+/-21.7, P<0.01) and 5 g/kg (the mucus thickness: 51.3+/-2.9 vs 36.1+/-7.2, NO: 0.480+/-0.026 vs 0.394+/-0.026, SOD: 186.4+/-19.9 vs 155.6+/-21.6, P<0.01) groups and CBP group (the mucus thickness: 51.3+/-2.9 vs 38.2+/-3.5, NO: 0.480+/-0.026 vs 0.395+/-0.053, SOD: 186.4+/-19.9 vs 156.3+/-18.1, P<0.01) in the mucus thickness, NO and SOD levels and better than 10 g/kg (86.8+/-7.6 vs 77.9+/-7.0, P<0.05) and 5 g/kg (86.8+/-7.6 vs 70.0+/-5.4, P<0.05) groups in 6-K-PGF(1)alpha level, 10 g/kg WK group was better than 5 g/kg WK (the mucus thickness: 43.3+/-2.9 vs 36.1+/-7.2, P<0.01, SOD: 168.2+/-21.7 vs 155.6+/-21.6, P<0.05) and CBP groups (the mucus thickness: 43.3+/-2.9 vs 38.2+/-3.5, P<0.01, SOD: 168.2+/-21.7 vs 156.3+/-18.1, P<0.05) in the mucus thickness and SOD level. In compound group, jianpiyiqi group, yangxuehuoxue group, qingrejiedu group, the level of ET was decreased, NO contents were increased in gastric tissue of ulcers in rats. CONCLUSION: WK decoction and separated recipes have significantly protective effect on ethanol-induced gastric mucosal injury. They can increase the content of EGF in gastric juice, PGI(2) SOD in plasma and NO in gastric tissues, thicken the mucus on the gastric mucosa, and decrease the impairing factor MDA, ET in plasma.

Simultaneous determination of quetiapine and three metabolites in human plasma by high-performance liquid chromatography-electrospray ionization mass spectrometry.

AIM: To develop a high performance liquid chromatography-electrospray mass spectrometry (HPLC-MS/ESI) method for simultaneous determination of quetiapine and its sulfoxide-, 7-hydroxy-, 7-hydroxy-N-dealkyl-metabolites in human plasma. METHODS: The HPLC separation of the compounds was performed on a Kromasil C18, (5 microm, 4.6 mm.150 mm) column, using water (formic acid: 1.70 mmol/L, ammonium acetate: 5.8 mmol/L)-acetonitrile (65:35) as mobile phase, with a flow-rate of 0.95 mL/min. The compounds were ionized in the electrospray ionization (ESI) ion source of the mass spectrometer and detected in the selected ion recording (SIR) mode. The samples were extracted using solid-phase extraction columns. RESULTS: The calibration curves were linear in the ranges of 10-2000 microg/L for quetiapine, 1-200 microg/L for its metabolites, respectively. The average extraction recoveries for all the four samples were above 85 %. The methodology recoveries were much higher than 95 %. The intra-day and inter-day RSD are less than 15 %. CONCLUSION: The method is accurate, sensitive, and simple for study of pharmacokinetics and metabolic mechanism of quetiapine in patients at therapeutic dose.