Production of xylanase under submerged fermentation from Bacillus firmus HS11 isolated from Sikkim Himalayan region

Xylanase producing microorganisms isolated from high altitude soil show activity at broad window of temperature, and can have variety of industrial applications. Here, we explored production of xylanase under submerged fermentation from Bacillus firmus HS11 isolated from Sikkim Himalayan region. We isolated 472 bacterial strains high altitude soil samples (1120-4272 m) from Sikkim and screened for xylanase production. Among them five strains that showed higher xylanase activity were identified by 16s rRNA gene sequence analysis. comparatively, Bacillus firmus HS11 showed highest activity at 10, 37 and 50°C, and was chosen for optimization experiment. B. firmus HS11 showed xylanase activity of 3.35 U/mg of protein at 37°C and retained 32.43% activity at 10°C and had 79.82% higher activity at 50°C. Optimization of nutrient composition for submerged fermentation of B. firmus HS11 was carried out by combination of Plackett-Burman design and response surface methodology. The optimized media component for xylanase production by submerged fermentation by B. firmus HS11 is beechwood xylan 0.8% (w/v), MgSO4 0.04% (w/v), CaCl20.04% (w/v), peptone 0.1% (w/v), NaCl 0.3% (w/v) and yeast extracts 0.01% (w/v), resulting in enhancement of xylanase production by 7.4 folds. Xylanase having activity at broad range of temperature including lower temperature can have application in food industry

Provoking Energy Cooperation in the South Countries: Renewable Energy in Brazil and India

In the current global context where developing countries try to articulate actions to deal with the energy crisis the dialogue appears as a fundamental element. The objective of this paper, through a convergent methodology based mainly on the literature review, is to provoke a reflection about the renewable energy cooperation between emerging countries bringing for that purpose the example of Brazil and India. The results show through a careful analysis that there are more elements in common to promote renewable energy between Brazil and India than suggested the hypothesis. The conclusion brings renewable energy cooperation as a way to be traced by developing countries, in this particularly case, Brazil and India, in search for a sustainable society. Keywords: Renewable Energy Cooperation, Brazil, India JEL Classifications: F59, P28, Q4

Is bitcoin a near stock? Linear and non-linear causal evidence from a price–volume relationship

The purpose of this paper is to examine the price–volume relationship in the bitcoin market to validate near-stock properties of bitcoin. Design/methodology/approach: Daily data of bitcoin returns, returns volatility and trading volume (TV) are utilized for the period August 17, 2010–April 16, 2017. Linear and non-linear causality tests are employed to examine price–volume relationship in the bitcoin market. Findings: The linear causality analysis indicates that the bitcoin TV cannot be used to predict return; however, the reverse causality is significant. In contrast, the non-linear causality analysis shows that there are non-linear feedbacks between the bitcoin TV and returns. The bitcoin TV, which represents new information, leads to price changes, and large positive price changes lead to increased trading activity. Similarly, in recent periods (post-break period), the results of the non-linear causality test show a unidirectional causality from TV to the volatility of returns. Research limitations/implications: This study uses the average index value of major bitcoin exchanges. But further research on this relationship using data from different bitcoin exchanges may provide further insights into the price–volume relationship of bitcoin and its near-stock properties. Practical implications: These findings from the non-linear causality analysis, therefore, suggest that investors cannot simply base their decisions on the linear dynamics of the bitcoin market. This is because new information in terms of the TV is neither linearly related to the price nor it is a one-to-one kind of relationship as most investors commonly understand it to be. Rather, investors’ decisions should be based on non-linear models, in general, and the best-fitting non-linear model, in particular. Originality/value: The study examines bitcoin’s near-stock properties in a price–volume relationship framework with the help of both linear and non-linear causality tests, which to the best of the authors’ knowledge remains unexplored

Multivariate analysis of fatty acid and biochemical constitutes of seaweeds to characterize their potential as bioresource for biofuel and fine chemicals

•Bio prospecting of seaweeds from tropical environment on the basis of composition.•C20:5n-3 eicosapentaenoic acid was detected in ten seaweeds.•Manifestation of chemotaxonomic relationship among thirty seaweeds. In the present study bio prospecting of thirty seaweeds from Indian coasts was analyzed for their biochemical components including pigments, fatty acid and ash content. Multivariate analysis of biochemical components and fatty acids was done using Principal Component Analysis (PCA) and Agglomerative hierarchical clustering (AHC) to manifest chemotaxonomic relationship among various seaweeds. The overall analysis suggests that these seaweeds have multi-functional properties and can be utilized as promising bioresource for proteins, lipids, pigments and carbohydrates for the food/feed and biofuel industry

Endophytic fungi of Panax sokpayensis produce bioactive ginsenoside Compound K in flask fermentation

Abstract Endophytes of Panax have the potential to produce their host plant secondary metabolites, ginsenosides. Panax sokpayensis, an endemic traditional medicinal plant of the Sikkim Himalayas was explored for the isolation of endophytic fungi. In the present study, we have isolated 35 endophytic fungal cultures from the rhizome of P. sokpayensis and screened for ginsenosides production by HPLC by comparing the peak retention time with that of standard ginsenosides. The HPLC analysis revealed that out of 35 isolates, the mycelial extracts of four fungal endophytes (PSRF52, PSRF53, PSRF49 and PSRF58) exhibited peaks with a similar retention time of the standard ginsenoside, Compound K (CK). LC–ESI–MS/MS analysis led to the confirmation of ginsenoside CK production by the four fungal endophytes which showed a compound with m/z 639.6278, similar to that of standard ginsenoside CK with yield in potato dextrose broth flask fermentation ranging from 0.0019 to 0.0386 mg/g of mycelial mass in dry weight basis. The four prospective fungal endophyte isolates were identified as Thermothielavioides terrestris PSRF52, Aspergillus sp. PSRF49, Rutstroemiaceae sp. strain PSRF53, and Phaeosphaeriaceae sp. strain PSRF58 based on ITS sequencing. The present finding highlights the need for further study on growth optimization and other culture parameters to exploit the endophytes as an alternative source for ginsenoside CK production

Bioflocculation: An alternative strategy for harvesting of microalgae - An overview

Microalgae based research has been extensively progressed for the production of value added products and biofuels. Potential application of microalgae for biofuel is recently gained more attention for possibilities of biodiesel and other high value metabolites. However, high cost of production of biomass associated with harvesting technologies is one of the major bottleneck for commercialization of algae based industrial product. Based on the operation economics, harvesting efficiency, technological possibilities, flocculation of algal biomass is a superior method for harvesting microalgae from the growth medium. In this article, latest trends of microalgal cell harvesting through flocculation are reviewed with emphasis on current progress and prospect in environmental friendly bio-based flocculation approach. Bioflocculation based microalgae harvesting technologies is a promising strategy for low cost microalgal biomass production for various applications. (C) 2017 Elsevier Ltd. All rights reserved

Major ginsenoside contents in rhizomes of <i>Panax sokpayensis</i> and <i>Panax bipinnatifidus</i>

<p>This study compared eight major ginsenosides (Rg1, Rg2, Rf, Re, Rd, Rc, Rb1 and Rb2) between <i>Panax sokpayensis</i> and <i>Panax bipinnatifidus</i> collected from Sikkim Himalaya, India. High-performance liquid chromatographic analysis revealed that all major ginsenosides were present in the rhizomes of <i>P</i>. <i>sokpayensis</i> except ginsenoside Rc, whereas ginsenoside Rf, Rc and Rb2 were not detected in <i>P</i>. <i>bipinnatifidus</i>.</p