Background: Avermectin B1b, a component of commercially available abamectin is obtained as fermentation product of Streptomyces avermitilis and has frequently been used as anthelmintic and insecticidal agent. Secondary metabolite production, avermectin B1b in present study, is dependent on medium composition therefore a proper medium should be designed for the fermentation process in order to have the best production. Objectives: The main objective of this study was the selection and optimization of medium for maximum production of avermectin B1b from S. avermitilis 41445. Materials and Methods: Eight different growth media were used for the production of avermectin B1b. Results: However the maximum production of avermectin B1b (17 mg/L) was obtained by using SM2 growth medium containing soluble corn starch, yeast extract, KCl, CaCO3 and MgSO4 which was detected qualitatively by using TLC and quantitatively by HPLC. Conclusions: Maximum production was observed with initial medium pH of 7, 10% inoculum size with incubation temperature of 31°C for 10 days of fermentation period.

Background:Streptomyces avermitilis, belonging to Actinomycetes, is specialized for production of avermectin, used as an anthelmintic and insecticidal agent. It is mostly found in soil and its isolation is very crucial for medically important avermectin production.Objectives:In the present study, 10 bacterial isolates lacking antimicrobial activities were isolated from the soil samples collected from different areas of Lahore, Pakistan.Materials and Methods:Three distinctive localities of Lahore were opted for soil assortment to isolate S. avermitilis. About 50 isolates of Streptomyces species were attained through selective prescreening procedures. All of these isolates were studied for production of the secondary metabolite, avermectin. Different test like soluble pigment color and melanin formation were used for identification. Biochemical characterizations of those isolates closely resembling the control in morphological characteristics, soluble pigment color and melanin formation tests were performed.Results:The 10 selected isolates were identified as the avermectin-producing strain by fermentation and characterized on ISP2 medium for aerial and reverse side mycelia color, soluble pigment color and melanin formation, in comparison with S. avermitilis DSM 41445. The best avermectin-producing isolate S1-C (10.15 mg/L) showed similar result as S. avermitilis DSM 41445, when subjected for culture characteristics analysis in different media along with biochemical characterization.Conclusions:From the results, it was concluded that agricultural lands around Pakistan Council of Scientific and Industrial Research (PCSIR) Campus Lahore were rich sources of industrially important Streptomyces, especially S. avermitilis.

Background:Secondary metabolite production from wild strains is very low for economical purpose therefore certain strain improvement strategies are required to achieve hundred times greater yield of metabolites. Most important strain improvement techniques include physical and chemical mutagenesis. Broad spectrum mutagenesis through UV irradiation is the most important and convenient physical method.Objectives:The present study was conducted for enhanced production of avermectin B1b from Streptomyces avermitilis 41445 by mutagenesis using ultraviolet (UV) radiation, ethidium bromide (EB), and ethyl methanesulfonate (EMS) as mutagens.Materials and Methods:S. avermitilis DSM 41445 maintained on yeast extract malt extract glucose medium (YMG) was used as inoculum for SM2 fermentation medium. Spores of S. avermitilis DSM 41445 were exposed to UV radiation for physical broad spectrum mutagenesis and to EMS and EB for chemical mutagenesis. For each mutagen, the lethality rate and mutation rate were calculated along with positive mutation rate.Results:Avermectin B1b-hyper-producing mutant, produced using these three different methods, was selected according to the HPLC results. The mutant obtained after 45 minutes of UV radiation to the spores of S. avermitilis 41445, was found to be the best mutant for the enhanced production of avermectin B1b component (254.14 mg/L). Other avermectin B1b-hyper-producing mutants, were obtained from EMS (1 µL/mL) and EB (30 µL/mL) treatments, and yielded 202.63 mg/L and 199.30 mg/L of B1b, respectively.Conclusions:The hereditary stability analysis of the UV mentioning 45 minutes revealed the UV exposure time for mutants and 3 represented the colony taken from the plate irradiated for 45 minutes mutant showed that the production of avermectin B1b remained constant and no reverse mutation occurred after 15 generations.

Disaster recovery is a continuous dilemma in cloud platform. Though sudden scaling up and scaling down of user's resource requests is available, the problem of servers down still persists getting users locked at vendor's end. This requires such a monitoring agent which will reduce the chances of disaster occurrence and server downtime. To come up with an efficient approach, previous researchers' techniques are analyzed and compared regarding prediction and monitoring of outages in cloud computing. A dual functionality Prediction and Monitoring Agent is proposed to intelligently monitor users' resources requests and to predict coming surges in web traffic using Linear Regression algorithm. This solution will help to predict the user's future requests' behavior, to monitor current progress of resources' usage, server virtualization and to improve overall disaster recovery process in Cloud Computing.

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