Exopolysaccharide (EPS) biopolymers produced by microorganisms play a crucial role in the environment such as health and bio-nanotechnology sectors, gelling agents in food and cosmetic industries in addition to bio-flocculants in the environmental sector as they are degradable, nontoxic. This study focuses on the improvement of EPS production through manipulation of different culture and environmental conditions using response surface methodology (RSM). Plackett–Burman design indicated that; molasses, yeast extract and incubation temperature are the most effective parameters. Box–Behnken RSM indicated that; the optimum concentration for each parameter was 12% (w/v) for molasses, 6 g/L yeast extract and 30 °C for incubation temperature. The most potent bacterial isolate was identified as Bacillus velezensis KY498625. After production, EPS was extracted, purified using DEAE-cellulose, identified using Fourier transform infrared (FTIR), gel permeation chromatography (GPC) and gas chromatography–mass spectroscopy (GC–MS). The result indicated that; it has molecular weight 1.14 × 105 D consisting of glucose, mannose and galactose.

The present work was designed for studying the efficiency of multi-factorial experimental designs to elucidate factors affecting exopolysaccharide production by K.oxytoca isolated from soil. Combinations of Plackett-Burman design (PBD) and BoxBehnken design (BBD) have been carried out for media optimization of various factors. Among 11 factors, yeast extract, molasses and incubation temperature were the most significant factors. These three factors were selected for further optimization using Box-Behnken design (BBD). The result obtained from data analysis showed that; the most optimum concentrations were yeast extract 6%, molasses12% and incubation temperature 37 0 C. Bacterial isolate was identified as Klebsiella oxytoca using 16 S rRNAgene sequences. This isolate was submitted to the gene bank with accession number KY498625.Biopolymer was purified using DEAE-cellulose and identified using Fourier transform infrared (FTIR), gel permeation chromatography (GPC) and Gas mass chromatography spectroscopy (GC-MS).The result showed that; average molecular weight (Mw) of 4.05 x10 4 Da; major monosaccharide constituents were mannose, glucose, Arabinose and Galacturonic acid.

Entomology Journal publishes original research papers and reviews from any entomological discipline or from directly allied fields in ecology, behavioral biology, Insects offer a source of novel natural compounds that may have therapeutic utility in cancer and other diseases. Antioxidant activity of these extracts was evaluated by DPPH (2,2-diphenyl-1picrylhydrazyl radical), and total antioxidant capacity assays. The antioxidant and anticancer effects of the crude extract of maggots namely; Musca domestica, Lucilia sericata and Chrysomya albiceps against the human colon carcinoma cell line (Caco-2), were investigated. The antioxidant activity of tested extracts revealed that the highest DPPH scavenging activity levels were exhibited by methanolic extract of C. albiceps, followed by those of L. sericata and M. domestica. Also, the highest effect was recorded against human colon carcinoma cell line (Caco-2) with L. sericata maggots methanolic extract, followed by those of C. albiceps and M. domestica at the highest concentration used (25 mg/ml). The IC 50 values of tested extracts ranged from 0.27 to 1.91 mg/ml. In conclusion, data suggest that tested extracts possess antioxidant and anticancer properties that may further explored as a potential source for treatment of cancer and other diseases involving oxidative stress.

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The present study dealt with evaluating the effect of different crude extracts from the larvae of palm weevil, Rhynchophorus ferrugineus and cotton leaf worm, Spodoptera littoralis on different pathogenic strains of bacteria and viruses. The results revealed that, ethyl acetate extracts of R. ferrugineus and S. littoralis larvae were more effective against different pathogenic bacterial strains tested than petroleum ether, chloroform, methanol and ethanol extract. Also, The MICs' determination showed that all different extracts of R. ferrugineus and S. littoralis larvae were active against tested bacterial strains. Minimum Inhibitory Concentration (MIC) values were ranged from 25 to 6.25mg/ml depended on tested species. Ethyl acetate extract from R. ferrugineus and S. littoralis larvae exhibited antiviral activity against hepatitis A virus (HAV) and Herpes simplex virus (HSV-1) cell lines at 625 & 312.5mg/ml. Ethyl acetate extract from R. ferrugineus and S. littoralis larvae recorded 5.19 & 4.07% antiviral activity against HAV at 625 & 312.5mg/ml, respectively; while, antiviral activity percentage was 12.42 & 26.17 at 625 and 312.5mg/ml, respectively against HSV-1. Tested extracts exhibited no antiviral activity against Coxsackie B virus (Cox B4) cell lines. Crude extracts of R. ferrugineus & S. littoralis were not cytotoxic to Vero (CCL-81) cells at 312.5 and/or 625μg/ml.