Showing papers by "Sanjay Ghosh published in 2008"
TL;DR: The present work reports for the first time, the alkali stable cellulase from alkali tolerant fungus Penicillium citrinum, which may have potential effectiveness as additives to laundry detergents.
Abstract: The enzymatic hydrolysis of cellulose has potential economical and environment-friendly applications. Therefore, discovery of new extremophilic cellulases is essential to meet the requirements of industry. Penicillium citrinum (MTCC 6489) that was previously isolated from soil in our laboratory, produced alkali tolerant and thermostable cellulases. Endoglucanase and filter paper activity hydrolase (FPAse) production of P. citrinum were studied using wheat bran substrate in solid state and submerged culture. Zymogram analysis of endoglucanase revealed the presence of two isoforms differing in molecular weight. One of them was 90 kDa and other one was 38 kDa. Partially purified endoglucanase showed two different peaks at pH 5.5 and 8.0, respectively, in its pH optima curve. But FPase showed only one peak (at pH 6.5) in its pH optima curve. Cellulase of P. citrinum is thermostable in nature. The present work reports for the first time, the alkali stable cellulase from alkali tolerant fungus Penicillium citrinum. Thermostable endoglucanase from P. citrinum may have potential effectiveness as additives to laundry detergents.
147 citations
TL;DR: In this paper, a new vegetation index, named the plant biochemical index (PBI), is proposed for improved estimation of the plant biochemicals from space-borne hyperspectral data; it is simply the ratio of reflectance at 810 and 560 nm.
Abstract: Remotely sensed estimates of biochemical parameters of agricultural crops are central to the precision management of agricultural crops (precision farming). Past research using in situ and airborne spectral reflectance measurements of various vegetation species has proved the usefulness of hyperspectral data for the estimation of various biochemical parameters of vegetation. In order to exploit the vast spectral and radiometric resources offered by space-borne hyperspectral remote sensing for the improved estimation of plant biochemical parameters, the relationships observed between spectral reflectance and various biochemical parameters at in situ and airborne levels needed to be evaluated in order to establish the existence of a reliable and stable relationship between spectral reflectance and plant biochemical parameters at the pixel scale. The potential of the EO-1 Hyperion hyperspectral sensor was investigated for the estimation of total chlorophyll and nitrogen concentrations of cotton crops in India by developing regression models between hyperspectral reflectance and laboratory measurements of leaf total chlorophyll and nitrogen concentrations. A comprehensive and rigorous analysis was carried out to identify the spectral bands and spectral indices for accurate retrieval of leaf total chlorophyll and nitrogen concentrations of cotton crop. The performance of these critical spectral reflectance indices was validated using independent samples. A new vegetation index, named the plant biochemical index (PBI), is proposed for improved estimation of the plant biochemicals from space-borne hyperspectral data; it is simply the ratio of reflectance at 810 and 560 nm. Further, the applicability of PBI to a different crop and at a different geographical location was also assessed. The present results suggest the use of space-borne hyperspectral data for accurate retrieval of leaf total chlorophyll and nitrogen concentrations and the proposed PBI has the potential to retrieve leaf total chlorophyll and nitrogen concentrations of various crops and at different geographical locations.
46 citations
TL;DR: Aza-Claisen rearrangement and ring-closing metathesis reaction were used for the synthesis of 1-benzazepine derivatives of pharmaceutical relevance as discussed by the authors.
Abstract: A synthetic strategy based on sequential application of aza-Claisen rearrangement and ring-closing metathesis reaction as key steps has been developed for the synthesis of various 1-benzazepine derivatives of pharmaceutical relevance.
7 citations
TL;DR: In this article, two site specific seasonal algorithms have been proposed for estimating the suspended sediments concentration (SSC) from the digital numbers recorded on Indian Remote sensing Satellite, IRS-P4 Ocean Colour Monitor (OCM) sensor.
Abstract: This article reports a preliminary work in which two site specific seasonal algorithms have been proposed for estimating the suspended sediments concentration (SSC) from the digital numbers recorded on Indian Remote sensing Satellite, IRS-P4 Ocean Colour Monitor (OCM) sensor. For estimation of SSC, the proposed algorithms utilize dark pixel deduction atmospheric correction technique. The computations are performed with respect to north east monsoon phase situations of Palk Strait coastal stretch. The algorithms performance was satisfactory during the north east monsoon period. Although the results obtained cannot be generalized, we suggest that the authority of proposed algorithms can be extended to other seasons with the addition of more temporal experimental validation data sets and with numeric constants adjusted to present existing conditions. (As this area was severely affected by Tsunami, it may have dissimilar conditions at present).
7 citations
TL;DR: In this article, a convergent protocol for the assembly of contiguous 2,4-linked polyoxazoles has been developed which allows efficient construction of suitably functionalized tetra -and pentaoxazole derivatives related to some macrocyclic bioactive natural products.
Abstract: A convergent protocol for the assembly of contiguous 2,4-linked polyoxazoles has been developed which allows efficient construction of suitably functionalized tetra - and pentaoxazole derivatives related to some macrocyclic bioactive natural products.
6 citations