The fresh leaves were dried for 6 hours at 50-60°C. The dried samples were then crushed into powder using an electronic blender. The powdered sample was stored in a bottle at room temperature, prior to analysis. Preparation of Extracts Ethanol extractionA powdered sample of 100 gm was weighed and soaked in 250 ml of 95% ethanol in a separating funnel for 24 hours, with intermittent shaking. The plant extract was then collected and filtered through Whatman No.1 filter paper. The extract was concentrated at 50°C using a rotatory evaporator and then air-dried. The dried powder was stored at 40°C in an airtight bottle. Similarly, the procedure was repeated with petroleum ether and water as solvents, using 100 gm of the fresh ground sample, for each extraction. All the extracts were cooled at room temperature. [2] Phytochemical Analysis The extracts were analyzed for the presence of phenols, tannins, alkaloids, anthraquinones, saponins, flavanoids, aminoacids and reducing sugars, using the standard procedure. [3] Agar-well Diffusion MethodThe antimicrobial activity was carried out by the agar-well diffusion assay using Muller Hinton agar plates. [4] The plates were swabbed with S. aureaus,

BackgroundPlant biomass and agricultural waste products disposal is a serious problem in agriculture based countries. These wastes, usually rich in xylan can be satisfactorily converted to industrially important and useful products by efficient biotechnological application of potent xylanase producing bacteria which generally have high temperature and pH optima.ObjectiveThe aim was to isolate and identify xylanolytic bacterial isolates from Bhilai-Durg region of Chhattisgarh, India which was otherwise unexplored for isolation of thermoalkalophilic xylanase producing bacteria. Partial scale up of process development was performed.Materials and MethodsXyalanse producing bacteria were isolated from probable samples following three stages of screening procedures. The potent isolates were identified and various parameters affecting xylanase production were optimized using the conventional one-factor-at-a-time approach.ResultsTwo potent indigenous bacterial isolates belonged to genus Bacillus and designated as Bacillus sp. MCC2728 and Bacillus sp. MCC2727 were isolated from forest soils with the ability to degrade xylan. Significant differences were observed in their morphology and phenotypic characters amongst themselves and with its closest type strains implying the novelty of the two isolates. After optimization, maximum xylanase levels were obtained at pH 9.0, 55 °C for Bacillus sp. MCC2728 and 50 °C for Bacillus sp. MCC2727, 5% inoculum, agitation speed (150 rpm). Yeast extract and peptone are best nitrogen sources and wheat bran, the best carbon source. The GenBank/EMBL/DDBJ accession numbers of strains Bacillus sp. MCC2728 and Bacillus sp. MCC2727 are KP742971 and KT444621 respectively. Wheat bran, Yeast extract and peptone proved to be the best carbon and nitrogen sources respectively and xylose as an additive was found to be contributing to maximize the xylanase yields.ConclusionTwo potent thermoalkalophilic novel bacterial isolates were successfully isolated with xylan degrading ability which may be used as promising xylanase producing candidates for various industrial purposes using agricultural based waste residues.

Xylanases are an important class of hydrolytic enzymes with a wide range of industrially important applications especially in paper and pulp industry. The present study aimed to take the advantage of statistical approach of optimization to investigate the interactive effects of prominent process factors involved in xylanase production. A novel bacterial isolate Bacillus sp. MCC 2727 was isolated from soil possessing xylanase producing ability at alkaline pH (9.2) and optimum temperature of 50°C. Using the conventional one-factor-at-a-time method, low cost agricultural waste; wheat bran, combination of peptone and yeast extract served as best carbon and nitrogen sources, respectively. MgSO 4 as metal salt and xylan as additive increased the xylanase productivity. Central composite design and response surface methodology were used to optimize these significant process parameters and for evaluation of interactive factors. Maximum xylanase activity of 205.3 IU/ml was obtained with 5% wheat bran, 1% each of yeast extract, peptone, xylan and MgSO 4 which was in consensus with the predicted value (207.2 IU/ml) which proved the validity and the accuracy of the statistical approach of optimization.

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