Phenotypic, genotypic characterization and racemic monochlorohydrin assimilating yeast from sugar cane juice

Vasugi S. and Suresh K.*

Isolation of yeasts from natural resources is the most successful technique to obtain yeast isolates that have abilities to utilize and ferment various compounds. Racemic monochlorohydrin assimilation and degradation yeast were screened from sugar cane mills using synthetic medium composed of 0.5% (v/v) racemic monochlorohydrin, 0.5% (NH4)2SO4, 0.1% K2HPO4, 0.1% Na2HPO4.12H2O, 0.2% NaH2PO4 2H2O, 0.05% MgSO4.7H2O, 0.001% FeSO4.7H2O, 0.0001% CuSO4.5H2O, 0.0001% MnSO4.5H2O and 0.008% bromothymol blue as pH indicator.

The strains were identified as Candida tropicalis MGR2 (KY209901), Clavispora lusitaniae MGR5 (KY209902), Wickerhamomyces anomalus MGR6 KY209903 and Candida albicans MGR9 (KY209906). In addition, phylogenetic analysis indicated that all the strains shared a cluster with yeast.

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Catalytic Esterification over Carbon based Solid Acid Catalyst: Optimization by Response Surface Methodology

Chandane Vishal S. and Rathod Ajit P.*

An efficient carbon based solid acid catalyst was developed from the sugarcane bagasse. The catalyst was characterized by SEM-EDX and BET surface area. The catalytic performance of carbon based catalyst was investigated in the esterification reaction of lactic acid with benzyl alcohol. The ester synthesized in the present study was benzyl lactate which has large applications in chemical industries as flavoring agent. The several process parameters were optimized by the Response Surface Methodology (RSM) with Box-Behnken design. The RSM model equations corresponding to the conversion of lactic acid was developed.

Analysis of variance (ANOVA) revealed that the acquired RSM model effectively interpreted the experimental data with the coefficient of determination (R2) value of 0.9551 and an adjusted R2 value of 0.8974. The RSM model predicted lactic acid conversion was 93.02% under the optimal process conditions; catalyst loading of 2.73 wt%, molar ratio of alcohol/acid of 5.17 and reaction temperature of 387 K. The model predicted conversion was validated experimentally and found to be in good agreement with an experimental value of 94.18 ±0.35. Recyclability study of catalyst elucidates that the catalyst possessed a significant stability and can be used effectively up to five reaction runs. This study describes the utilization of sugarcane bagasse to develop a heterogeneous solid acid catalyst for the industrially important esterification reactions.

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Lagenaria siceraria aided green synthesis of ZnO NPs: Anti-dandruff, Anti-microbial and Anti-arthritic activity

Kalpana V.N., Chakraborthi Payel and Devi Rajeswari V.*

In the present investigation, ZnO NPs were green synthesized using Lagenaria siceraria Pulp extract. The physicochemical properties of ZnO NPs were characterized using UV-Visible spectro-photometer, X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FT-IR) and Scanning electron microscopy (SEM) analysis. Further, the biosynthesized ZnO Nanoparticles have been used for evaluating anti-dandruff, anti-microbial and anti-arthritic efficacy. Anti-dandruff activity was assessed against Malassezia furfur MTCC 1765 and Malassezia pachydermatis MTCC No. 1369 and anti-microbial activity was assessed against Klebsiella pneumoniae MTCC No. 9401, Escherichia coli MTCC No. 1691, Staphylococcus aureus MTCC. No. 9542, Listeria monocytogenes MTCC No. 657 and Salmonella sp MTCC No. 1169.

In anti-arthritic activity, the percentage stabilization of aqueous extract was found to be 82% and ZnO NPs were found to be 89 % inhibition on BSA method which confirms the anti-arthritic activity. Finally, our results proved that green synthesized ZnO NPs using L. siceraria have a great potential in biomedical applications.

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Study of Ternary Complex Stability Constants of Co(II), Ni(II) and Cu(II) with 5-Sulfosalicylic acid and 5-Hydroxysalicylic acid in DMF-Water Mixtures

Balakrishna M.* and Srinivasa Rao G.*

A computer assisted pH-metric investigation has been carried out on the speciation of complexes of Co(II), Ni(II) and Cu(II) with 5-Sulfosalicylic acid and 5-Hydroxysalicylic acid. The titrations were performed in the presence of different relative concentrations (M:L:X = 1.0:2.5:2.5; 1.0:2.5:5.0; 1.0:5.0:2.5) of metal (M) to 5-Sulfosalicylic acid (L) and 5-Hydroxysalicylic acid (X) with sodium hydroxide in varying concentrations (0.0-60.0% v/v) of DMF-water mixtures at an ionic strength of 0.16 mol L-1 and at a temperature of 303.0 K.

Stability constants of the ternary complexes were refined using MINIQUAD75. The species MLXH, MLX2H2 and ML2XH for Co(II), Ni(II) and Cu(II) were detected. The extra stability of ternary complexes compared to their binary complexes was believed to be due to electrostatic interactions of the side chains of ligands, charge neutralization, chelate effect, stacking interactions and hydrogen bonding. The species distribution with pH at different compositions of DMF-water mixtures and plausible equilibria for the formation of species also presented.

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Study of selected biochemical parameters related to submergence tolerance in rice (Oryza sativa L.) with special reference to land races and wild species

Goswami Sayani*, Kar Rup Kumar, Paul Anupam and Dey Narottam*

A selection of twelve rice lines, mainly grown by marginal farmers in the lowland flood prone regions of West Bengal and Odisha and known for their submergence tolerant or elongating properties, were studied in context of their biochemical changes due to submergence stress. Two more rice lines, FR13A and IR42, were also included as submergence tolerant and susceptible checked varieties respectively.

The parameters studied, namely, total chlorophyll, total protein, soluble and insoluble carbohydrate, amylase, invertase, pyruvate decarboxylase (PDC) and alcohol dehydrogenase (ADH), are linked to submergence stress tolerance. FR13A, Khoda, Kumrogore, Kalaputia, Meghi and Bhashakalmi showed lower degradation of chlorophyll during submergence. Bhashakalmi also showed highest protein content during submergence. Both these parameters are indicators of better submergence stress tolerance of plants. In FR13A, Meghi, Khoda, Bhashakalmi, Swarna-sub1, the amount of soluble carbohydrate, during submergence, is on the lower side as they store the carbohydrate for later survival and recovery. In case of insoluble carbohydrate, in Harmanona and Panibhasha the amount is very low during submergence.

In Moule, Harmanona, Panibhasha, Narayankamini very high amount of carbohydrate metabolising enzymes (amylase and invertase) can be seen during submergence which indicates their deepwater elongating nature under flood stress. Apart from FR13A, in Meghi and Khoda, a marked increase of ADH and PDC (enzymes of alcoholic fermentation pathway) can be seen during submergence which is indicative of their better performance under submergence stress. From this overall study it can be concluded that Meghi, Khoda, Kumrogore, Bhashakalmi and Kalaputia are the best performing varieties amongst the selected fourteen and this experimental work can be used for characterization of the submergence tolerant rice landraces.

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Synthesis of CaSO4 nanoparticles and effect on PA6/CaSO4 nanocomposite for investigation of thermal and viscoelastic properties

Barman Ghanshyam, Sonawane Shriram S.*, Wasewar Kailas L., Rathod Ajit P., Sonawane Shirish H. and Shimpi Navin G.

This research work represents the synthesis of calcium sulphate (CaSO4) nanoparticles and its effect on the thermal stability and the viscoelastic behavior of the PA6. PA6/CaSO4 nanocomposites were prepared by melt compounding of PA6 and CaSO4 nanoparticles. The properties of nanocomposite were compared with neat PA6. The thermal stability, thermomechanical and viscoelastic behavior of PA6 matrix were improved with incorporation of CaSO4 nanoparticles.

The result analysis confirms that increase in CaSO4 loading enhances the thermal stability and viscoelastic property of PA6. The improvement in properties was due to superior intermolecular interaction between the nanoparticles and polyamide 6 matrix. The XRD, SEM, TGA, DSC and DMA characterization confirms the improvement in thermal and viscoelastic properties.

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Photo-Fenton Decolourization of Methylene Blue Adsolubilized on Co(II)- Embedded Alumina Surface: Comparison of Process Modeling by RSM and ANN

Mahamallik Prateeksha and Pal Anjali*

In our recent report we described a new catalyst for methylene blue (MB) degradation via modified photo-Fenton process. The catalyst was Co(II) adsorbed on surfactant-modified alumina (SMA). This material was designated as Co-SMA. During the degradation, the dye MB was initially adsolubilized on the Co-SMA surface and then its decolorization was carried out by visible light photo-Fenton process. The novelty of the reaction was that the entire reaction proceeded on solid surface. This type of adsolubilization based approach for photo-Fenton degradation is new. The maximum decolourization of MB for a particular operating condition was experimentally determined using “one-factor-at-a-time” approach. Such an approach is time consuming and needs more number of experiments to decide the optimum conditions.

In the present work, response surface methodology (RSM) and artificial neural network (ANN) were applied for modeling the same decolorization of MB by photo-Fenton process as a function of dose of Co-SMA (10, 20 and 30 g/L), initial concentration of MB (10, 20 and 30 mg/L), concentration of H2O2 (174.4, 348.8 and 523.2 mM) and reaction time (30, 45 and 60 min). The prediction capabilities of both the methodologies (RSM and ANN) were compared on the basis of correlation coefficient (R2), root mean square error (RMSE), standard error of prediction (SEP) and relative percent deviation (RPD). Due to lower value of RMSE (1.27), SEP (2.06) and RPD (1.17) and higher value of R2 (0.9966), ANN was proved to be more accurate than RSM in order to predict decolorization efficiency of MB.

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