Antioxidative Effect of Large Molecular Polymeric Pigments Extracted from Zijuan Pu-erh Tea In Vitro and In Vivo

ABSTRACT The antioxidative effect of large molecular polymeric pigments (LMPP) extracted from Zijuan Pu-erh tea was investigated in vitro and in vivo. The results showed that LMPP had signifi cant scavenging activities on the hydroxyl radical and the 2, 2-diphenyl-1-picrylhydrazyl (DPPH) radical in vitro and showed strong reducing power. Moreover, the 50% inhibitory concentrations of LMPP for scavenging DPPH radical and hydroxyl radical were 0.217 mg.mL -1 and 0.461 mg.mL -1 , respectively. In vivo, the LMPP-treated rat groups showed signifi cantly increased serum superoxide dismutase (SOD) and glutathione peroxidase (GSH-PX) activities, reduced malondialdehyde (MDA) formation, increased nitric oxide (NO) production and signifi cantly decreased rat endothelin-1(ET-1) concentrations compared with those in the hyperlipidemia model group (P < 0.05). The serum SOD and GSH-PX activities and NO concentration were 66.88, 29.09 and 55.11% higher, respectively, whereas, the serum ET-1 and MDA concentrations were 34.62 and 59.11% lower in the high-dose LMPP treatment group (1.215 g.kg -1 body weight) than in the hyperlipidemia model group (P < 0.05). These results showed that LMPP has a good antioxidative function and can be considered as a natural antioxidant source

Biosorption of nonylphenol on dead biomass of Rhizopus arrhizus encapsulated in chitosan beads

The nonylphenol (NP) biosorption and desorption potential for fungal biomass used under batch conditions was investigated using kinetics and isotherm models. Fungal biomass of Rhizopus arrhizus TISTR 3610 exhibited preferential uptake of NP, an endocrine disrupting chemicals. Sporangiospores, asexual spores, were immobilisation in chitosan beads. The biosorption data of NP on the moist heat inactivated R. arrhizus-chitosan beads were analyzed using four popular adsorption isotherms and, by using non-linear least-regression with the solver add-in in Microsoft Excel, correlated in order with the Fritz-Schlüender > Redlich-Peterson > Freundlich > Langmuir isotherms. The pseudo first-order kinetics was found to have the best fit with the experimental data. The diffusivity of NP in the R. arrhizus-chitosan beads was calculated using the shrinking core model, and the diffusivity values were in the ranges of 2.3736 x 10^[-4] to 1.8950 x 10^[-4] cm^[2]s^[-1]. Desorption to recover the adsorbed NP from the beads was performed in methanol and was best described using a pseudo second-order kinetic model

Nonreducing terminal chimeric isomaltomegalosaccharide and its integration with azoreductase for the remediation of soil-contaminated lipophilic azo dyes

Lipophilic azo dyes are practically water-insoluble, and their dissolution by organic solvents and surfactants is harmful to biological treatment with living cells and enzymes. This study aimed to evaluate the feasibility of a newly synthesized nonreducing terminal chimeric isomaltomegalosaccharide (N-IMS) as a nontoxic solubilizer of four simulated lipophilic azo dye wastes for enzymatic degradation. N-IMS bearing a helical α-(1 → 4)-glucosidic segment derived from a donor substrate α-cyclodextrin was produced by a coupling reaction of cyclodextrin glucanotransferase. Inclusion complexing by N-IMS overcame the solubility issue with equilibrium constants of 1786-242 M-1 (methyl yellow > ethyl red > methyl red > azo violet). Circular dichroism spectra revealed the axial alignment of the aromatic rings in the N-IMS cavity, while UV-visible absorption quenching revealed that the azo bond of methyl yellow was particularly induced. Desorption of the dyes from acidic and neutral soils was specific to aqueous organic over alkali extraction. The dissolution kinetics of the incorporated dyes followed a sigmoid pattern facilitating the subsequent decolorization process with azoreductase. It was demonstrated that after soil extraction, the solid dyes dissolved with N-IMS assistance and spontaneously digested by coupled azoreductase/glucose dehydrogenase (for a cofactor regeneration system) with the liberation of the corresponding aromatic amine

Development of the model to predict the growth of Salmonella spp. in stirred fried rice with crab meat

Central Composite Design (CCD) was used to study the main factors (temperature, pH, salt concentrations, initial inoculums and incubation time) affecting Salmonella enteritidis growth in stirred fried rice with crab meat. The result obtained from the CCD, fits in the second-order model using a quadratic polynomial equation.Y = 37.024 - 0.005 INOC + 7.7 x 10-7 INOC2 + 0.001 INOC. pH + 3.5x10-4 INOC.Time + 3.131 NaCl+ 7.713 NaCl2 - 6.8x10-5 NaCl.INOC - 2.20 NaCl.pH + 0.148 NaCl.Time - 11.0 pH + 0.0927 pH2+ 0.037 pH.Time + 0.489 Temp - 0.003 Temp2 - 2.3x10-4 Temp.INOC - 0.056 Temp.NaCl - 0.019Temp.pH + 0.007 Time.Temp - 0.619 Time - 6.00x10-4 Time2.The model is developed for wider application. The new equation is as follows:Y = 37.024 - 0.005 INOC + 0.001 INOC. pH + 3.5x10-4 INOC.Time + 3.131 NaCl + 7.713 NaCl2 - 2.20NaCl.pH + 0.148 NaCl.Time - 11.0 pH + 0.0927pH2 + 0.037 pH.Time + 0.489 Temp - 0.003 Temp2- 2.3x10-4 Temp.INOC - 0.056 Temp.NaCl - 0.019 Temp.pH + 0.007 Time.Temp - 0.619 Time .This new model is used to predict the population of Salmonella enteritidis, Salmonella amsterdam, Salmonella bangkok and Salmonella dublin in stirred fried rice with crab meat grew at different conditions. It is found that the new model accuracy is 94.93, 79.36, 88.39 and 96.33 per cent to predict growths of of Salmonella enteritidis, Salmonella amsterdam, Salmonella bangkok and Salmonella Dublin, respectively

Factors Affecting the Biomass and Lipid Production from Chlorella sp. TISTR 8990 under Mixotrophic Culture

Effects of media compositions on biomass and lipid accumulation of the isolate Chlorella sp. TISTR 8990 were investigated under a Plackett-Burman experimental design with mixotrophic cultivation conditions. Under this experimental design there were 15 different runs with ten factors-yeast extract, KH2PO4, MgSO4, FeSO4, MnCl2, CuSO4, Na2MoO4, H3BO3, ZnSO4 and pH. Cultures were grown mixotrophically under 16 h light and 8 h dark regime at 30 ºC for a period of 7 days. During the light regime, the light intensity at the surface of the vessels and agitation speed were set to 67.5 µmol photons m-2s-1 and 150 rpm, respectively. Initial cell concentration was set to an absorbance (A540) of 0.5. For high biomass production (2.2 g/L, run no. 6), the most effective and significant factors were yeast extract, KH2PO4, FeSO4 and ZnSO4 at concentrations 0.3 g/L, 0.3 g/L, 3 mg/L and 0.3 mg/L, respectively. Whereas for high lipid accumulation (19.59 %DCW, run no. 2), these were KH2PO4, pH and yeast extract, at a level of 1.7 g/L, 6.0 and 0.1 g/L, respectively. No significant factors were obtained for higher lipid content. The best treatment for biomass and lipid content was run no. 6, whose medium formula consisted of 0.3 g/L yeast extract, 1.7 g/L KH2PO4, 1.7 g/L MgSO4, 1 mg/L FeSO4, 0.9 mg/L MnCl2, and pH 7.0, together with fixed concentrations of glucose, NaHCO3 and KNO3 at 5 g/L, 0.05 g/L and 0.5 g/L, respectively

Optimization of Cyclodextrin Production From Sago Starch

Cyclodextrin (CD) is synthesized by bacterial cyclodextrin glycosyltransferase (CGTase) and is widely used in food, pharmaceutical, cosmetic, and agricultural industries. In this study, Bacillus circulans CGTase was partially purified by ammonium sulfate precipitation at 50--70% saturation. The optimum pH and temperature for CD production from sago starch were found to be in the ranges of 4.5--5.0 and 55--60 #C, respectively. b-CD was the predominant product, constituting 65% of all CD products. The b-CD produced using partially purified and crude CGTase were compared and found to have no significant di#erence in yield and productivity. The appropriate proportion of CGTase to sago starch for b-CD production was determined by response surface methodology. The most appropriate enzyme:substrate ratio was 50 U g sago starch #1 CGTase and 60 g l #1 sago starch