Effect of Ascorbic Acid on Oxidative Stress Parameters of Fruit Fly in the Presence of Fe (II).

Excessive iron intake causes lipid peroxidation and increases oxidative stress. Ascorbic acid is a natural compound with antioxidant and therapeutic properties. In this study, the effect of AA on oxidative stress parameters in fruit flies in the presence of iron was investigated. Third instar larvae were exposed to Fe and/or AA. Antioxidant enzyme activities, MDA, and GSH levels were determined in adult heads developing from the larvae. The mRNA levels of the enzymes were also analyzed. Iron treatment caused inhibition of SOD, CAT, and GPx enzymes, and only a decrease in the mRNA level of CAT. However, AA treatment together with iron prevented the inhibition. In addition, iron treatment increased the MDA level and decreased the GSH level. AA treatment together with iron ameliorated the changes in MDA and GSH levels. The results showed that AA can interfere with the iron-induced changes. Considering the potential of AA to ameliorate iron-induced changes, further studies are needed to elucidate the effect of AA on different mechanisms.

Exopolysaccharide of Anoxybacillus pushchinoensis G11 has antitumor and antibiofilm activities.

Exopolysaccharides (EPS/EPSs) possess several various applications in the food and pharmaceutical industries. This study was performed to investigate the biological (antibiofilm and antitumor), rheological (temperature, shear rate, and density) and chemical (solubility, carbohydrate and protein content, composition, molecular weight, functional group analysis, thermal analysis, X-ray diffraction pattern and scanning electron microscopy) properties of the EPS, which was purified from the locally isolated thermophilic bacterium Anoxybacillus pushchinoensis G11 (MN720646). EPS was found to have antibiofilm and antitumor [lung (A-549) and colon (Caco-2 and HT-29) cancer] activities. The viscosity of EPS showing Newtonian flow was temperature dependent. As chemical properties, the EPS was found to be a heteropolysaccharide containing arabinose (57%), fructose (26%), glucose (12%), and galactose (5%). EPS contained 93% carbohydrates and 1.08% protein. The molecular weight of EPS was determined as 75.5 kDa. The FTIR analysis confirmed the presence of sulfate ester (band at 1217 cm-1), an indication of the antitumor effect. The EPS was semi-crystalline. It could maintain 36% of its weight at 800 °C and crystallization and melting temperatures were 221 and 255.6 °C. This is the first report on the EPS production potential and the biological activity of A. pushchinoensis.

A novel endo-ß-1,4-xylanase from Pediococcus acidilactici GC25; purification, characterization and application in clarification of fruit juices.

A novel extracellular xylanase was purified and characterized from Pediococcus acidilactici GC25 (GenBank number: MF289522). The purification was 4.6-fold with a yield of 43.61% through acetone precipitation, Q-Sepharose, and CM-Sepharose ion change chromatography. The molecular weight of the enzyme was 48.15 kDa, and the optimum pH and temperature were 7.0 and 40 °C, respectively. The maximum activity was observed between 20 and 50 °C. Although it was active within a wide pH range (pH 2.0-9.0), it retained over 85% of its activity after 24 h incubation; and over 70% of its activity after 168 h incubation in neutral and alkaline pH. It was observed that the enzyme showed high stability with K+, Ba2+, Cd2+, Co2+, Sr2+, Mg2+, Ca2+, Al3+, Zn2+, and Ni2+ ions. The Km and Vmax for the xylanase were 3.10 mg mL-1 and 4.66 U/mg protein, respectively. It was determined that treatment of different fruit juices with P. acidilactici GC25 xylanase improved the clarification. The highest increase in the reducing sugar amount and decrease in the turbidity was 24.47 ±â€¯1.08 and 21.22 ±â€¯0.58 for peach juice at 0.15 U/mL enzyme concentration. These results showed that the xylanase purified from P. acidilactici GC25 may have a wide potential in biotechnological processes of the food and baking industry.

New xylanolytic enzyme from Geobacillus galactosidasius BS61 from a geothermal resource in Turkey.

In this study, isolation, conventional and molecular characterizations of ten thermophilic bacteria from Rize/Ayder were carried out. Xylanase from Geobacillus galactosidasius BS61 (GenBank number: KX447660) was purified by acetone precipitation, Diethylaminoethyl-cellulose and Sephadex G-100 chromatographies. The xylanase of G. galactosidasius BS61 in clarifying fruit juice was also investigated. Enzyme was purified 29.80-fold with 75.18% yield; and molecular weight was determined as 78.15 kDa. The optimum temperature of xylanase was 60 °C. The enzyme activity was maintained fully after 24 h and over 50% after 168 h at pH 4.0-10.0, while optimum pH was 7.0. Km and Vmax for beech wood xylan were measured as 3.18 mg mL-1, 123 U mg protein-1. In addition, Ca2+, Na+, Al3+, Zn2+, Cd2+, Mg2+, Ni2+, Cu2+ had decreasing effect on enzyme activity, while enzyme activity had been protected against anions, especially HSO3- and HPO42- stimulated enzyme activity. Xylanase applications (with 15 U/mL enzyme activity) in orange and pomegranate juices were increased; and the sugar and turbidity amounts were reduced 17.36% ±â€¯1.18 and 30.52 ±â€¯1.23, respectively. These results indicated that the xylanase of G. galactosidasius BS61 has biotechnological potential in juice clarification due to its stability against metal ions, chemicals and high pH-values.

Cytotoxic effect of Rosa canina extract on human colon cancer cells through repression of telomerase expression.

Rosa canina is a member of the genus Rosa that has long been used for medical objectives. Several studies have reported cytotoxic effects of different Rosa species, but there has been only limited investigation of the cytotoxic effect of R. canina. The purpose of the current study was to examine the potential effect of R. canina extract on cell viability, the cell cycle, apoptosis, and the expression of telomerase in human colon cancer (WiDr) cells. The cytotoxic effect of the extract was determined using MTT assay. The mechanism involved in the cytotoxic effect of the extract was then evaluated in terms of apoptosis and the cell cycle using flow cytometry. Mitochondrial membrane potential (MMP) was investigated using the fluorometric method, and expression levels of telomerase were studied using RT-PCR. R. canina extract exhibited a selective cytotoxic effect on WiDr cells compared with normal colon cells. The extract induced cell cycle arrest at the S phase and apoptosis via reduced MMP in WiDr cells. R. canina extract significantly repressed telomerase expressions at treatment times of 48 and 72 h in WiDr cells. Our results suggest that R. canina may have considerable potential for development as a novel natural product-based anticancer agent.

Cytotoxic effect of Rosa canina extract on human colon cancer cells through repression of telomerase expression / 药物分析学报

Rosa canina is a member of the genus Rosa that has long been used for medical objectives. Several studies have reported cytotoxic effects of different Rosa species, but there has been only limited investigation of the cytotoxic effect of R. canina. The purpose of the current study was to examine the potential effect of R. canina extract on cell viability, the cell cycle, apoptosis, and the expression of telomerase in human colon cancer (WiDr) cells. The cytotoxic effect of the extract was determined using MTT assay. The mechanism involved in the cytotoxic effect of the extract was then evaluated in terms of apoptosis and the cell cycle using flow cytometry. Mitochondrial membrane potential (MMP) was investigated using the fluorometric method, and expression levels of telomerase were studied using RT-PCR. R. canina extract exhibited a selective cytotoxic effect on WiDr cells compared with normal colon cells. The extract induced cell cycle arrest at the S phase and apoptosis via reduced MMP in WiDr cells. R. canina extract significantly repressed telomerase expressions at treatment times of 48 and 72 h in WiDr cells. Our results suggest that R. canina may have considerable potential for development as a novel natural product-based anticancer agent.

Purification and characterization of an extracellular cellulase from Anoxybacillus gonensis O9 isolated from geothermal area in Turkey.

In the present study, cellulase was purified and characterized from Anoxybacillus gonensis (Gen bank Number: KM596794) which was isolated and characterized from Agri Diyadin Hot spring. It was found to synthesize cellulase which had a wide range of industrial applications. Twenty four-hour-cultured bacteria induced cellulase production and specific activities during the purification steps were 1.47, 81.06 and 109.4 EU mg(-1) protein at crude extract, ammonium sulphate precipitated and DEAE-Sephadex purification steps. The highest enzyme activity was observed at 50°C and the optimum range of pH was 3-10. Molecular weight of enzyme was determined approximately 40kDa. The kinetic parameters of cellulase against carboxymethylcellulose (CMC) were 153.4 pmol min(-1) mg for Vmax and 0.46mM for Km. Among effectors of the enzyme, Zn2+, Ca2+, Co2+ and EDTA decreased enzyme activity.