Postprandial hyperglycemia plays an important role in the development of type 2 diabetes. Inhibition of alpha-amylase was led to a delay in breaks down of starch and glycogen and prevented a rapid rise in blood sugar. Alpha-amylase was isolated by gel filtration chromatography Sephadex G-75 from bovine pancreas. Then, total methanolic extracts of plants were prepared and IC50values of extracts on alpha-amylase were obtained and compared with acarbose IC50. The polyphenolic content of extracts and antioxidant capacity were determined by Folin-Ciocalteu test and DPPH test, respectively. The specific activity of alpha-amylase was 48.2 U/mg. For inhibition of alpha-amylase, IC50values ofH. persicum,Z. jujuba, and acarbose were 307, 827, and 113 μg/ml, respectively. For inhibition of DPPH radical, IC50values of extracts were 235 and 701 μg/ml. Total phenolic contents of methanol extracts were73.8±3.2and44.2±1.8 μg tannic acid equivalent/mg extract. Acarbose causes gastrointestinal symptoms and liver toxicity, butH. persicumandZ. jujubadecrease these side effects and prevent gastrointestinal disorders. Due to the high polyphenolic content and antioxidant capacity of these plants and significant inhibitory effect of the plants on alpha-amylase, these plants can be proposed for treatment of diabetic patients.

BACKGROUND Cellulose as a renewable biomaterial has forced attention on the use of cellulose‐hydrolyzing enzymes for industrial bioconversion of lignocellulosic materials to glucose. This paper reports immobilization of cross‐linked cellulase aggregates (CLEA) on the amine‐functionalized Fe3O4@silica core‐shell magnetic nanoparticles (MNPs). RESULTS The optimum pH of the cellulase cocktail upon immobilization (cellulase CLEA–MNP) shifted a little to the acidic side whereas the optimum temperature did not change significantly. The behavior of CMCase activity in the cellulase CLEA–MNP at pH and temperature values higher than the optimum was significantly different compared with free cellulase. Cellulase CLEA–MNP retained about 45% of its maximum activity at pH values higher than 4.8, while free cellulase lost its activity sharply. Immobilized cellulase in contrast to the free form retained about 65% of its maximum activity at 80°C. Cellulase CLEA–MNP had improved thermal stability at 65°C. Operational stability of the immobilized cellulase was also noticeable. After a sharp decrease during two cycles of CMC hydrolysis, cellulase CLEA–MNP retained 30% of its initial activity through six cycles of reuse. CONCLUSION Simple separation of MNPs from reaction medium and durability of CLEA–MNP composite during repeated use may overcome the major bottleneck against comprehensive applications of cellulase enzymes in industry. © 2014 Society of Chemical Industry

Expression of human epidermal growth factor receptor type 2 (HER2) in head and neck squamous cell carcinoma (HNSCC) cell line HN5 can be employed with great opportunities of success for specific targeting of anti-cancer chemotherapeutic agents. In the current study, HER2-specific affibody molecule, ZHER2:342 (an engineered protein with great affinity for HER2 receptors) was selected for conjugation to idarubicin (an anti-neoplastic antibiotic). ZHER2:342 affibody gene with one added cysteine code at the its 5' end was synthesized de novo and then inserted into pET302 plasmid and transferred to E. Coli BL21 hosting system. After induction of protein expression, the recombinant ZHER2 affibody molecules were purified using Ni-NTA resin and purity was analyzed through SDS-PAGE. Affinity-purified affibody molecules were conjugated to idarubicin through a heterobifunctional crosslinker, sulfosuccinimidyl 4-(N-maleimidomethyl)cyclohexane-1-carboxylate (Sulfo-SMCC). Specific toxicity of idarubicin-ZHER2 affibody conjugate against two HER2-positive cells, HN5 and MCF7 was assessed through MTT assay after an exposure time of 48 hours with different concentrations of conjugate. Idarubicin in the non-conjugated form showed potent toxic effects against both cell lines, while HN5 cells were significantly more sensitive compared to MCF-7 cells. Dimeric ZHER2 affibody showed a mild decreasing effect on growth of both HN5 and MCF-7 cells at optimum concentration. Idarubicin-ZHER2 affibody conjugate at an optimum concentration reduced viability of HN5 cell line more efficiently compared to MCF-7 cell line. In conclusion, idarubicin-ZHER2 affibody conjugate in optimum concentrations can be used for specific targeting and killing of HN5 cells.

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Reproductive toxicity of carboxyl-functionalised carbon nanotubes (CNT-COOH), as the most commonly used form of water-soluble CNTs, is not clearly studied. The aim of this study was to investigate in vitro toxicity of carboxylated single-walled and multi-walled CNTs (SWCNT-COOH and MWCNT-COOH) against human spermatozoa. Sperm cells from healthy donors were incubated with 0.1-100 μg/ml of SWCNT-COOH or MWCNT-COOH at 37°C for up to 5 hr. Viability of sperm cells was assessed using MTT test, and sperm motility was evaluated following World Health Organization guideline. Production of reactive oxygen species (ROS) and nitric oxide (NO) in sperm was also assessed. We showed that both MWCNT-COOH and SWCNT-COOH following incubation in vitro with human spermatozoa did not exert negative effect on viability while motility was significantly (p < .05) dropped in a dose-dependent manner. Moreover, there was no significant effect of the type, dose and exposure time of the CNT-COOH on NO production. Exposure of sperm cells to both examined types of CNTs at concentrations as low as 0.1 μg/ml caused a significant increase in ROS levels. In conclusion, carboxylated forms of CNTs seem to be harmful for human spermatozoa. Further studies, especially using in vivo models, are needed to decide about reprotoxicity of carboxylated forms of CNTs.