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Item Direct saponification of wet microalgae by methanolic potassium hydroxide using acetone as co-solvent(Elsevier, 2019-02) Verma, Sanjay KumarThe fatty acids of microalgae are promising source of biodiesel and omega-3 fatty acids. The objective of this study is extraction of fatty acids from wet Dunaliela salina by direct saponification using methanolic potassium hydroxide and a suitable co-solvent. The study identified acetone as an efficient co-solvent for saponification of wet microalgal biomass by methanolic potassium hydroxide. The presence of acetone in methanolic KOH saponification produced 24% more fatty acid than its absence. Further optimization of concentration of acetone (80% v/v), concentration of potassium hydroxide (0.1% v/v) and solvent-dry biomass ratio (75:1) resulted in a maximum yield of 98% fatty acid. The proposed acetone assisted saponification of wet microalgal biomass could serve as an energy efficient route for fatty acid production since the reaction happens under room temperature and normal atmospheric pressure without any cell lysis or drying the biomass.Item Decolourization of Orange G Dye by Microalgae Acutodesmus obliquues Strain PSV2 Isolated from Textile Industrial Site(IJASB, 2013-12) Verma, Sanjay KumarRelease of different types of synthetic dyes into the aquatic environment by various industrial sources is a major area of concern worldwide due to their low biodegradable nature. Conventional methods of dye removal are effective but high operating cost and energy requirement, generation of toxic sludge and regeneration problem of adsorbent limits their use at large scale. Biosorption of dye molecules by microorganisms is an economic and eco friendly technology for the treatment of textile wastewater.Item Adsorption of Acid Red 66 Dye from Aqueous Solution by Green Microalgae Acutodesmus obliquus Strain PSV2 Isolated from an Industrial Polluted Site(Scientific Research, 2014-06) Verma, Sanjay KumarIn the present study, Acutodesmus obliquus strain PSV2 was isolated from a textile and dyeing industrial site and investigated as a cost effective and potential adsorbent for Acid red 66 dye. Batch kinetic experiments were carried out as a function of pH (1.0 - 6.0), contact time (0 - 180 min) and initial dye concentration (10 - 50 mg/L) to determine the decolorization efficiency of microalgae. The maximum adsorption of dye was observed at pH 2.0 during the initial 60 min of contact time. The Langmuir and Freundlich adsorption isotherms were applied to experimental data to investigate the efficiency of adsorbent and mechanism of adsorption. It was observed that Langmuir and Freundlich isotherm fitted well with Acid Red 66 dye data. Langmuir isotherm, described maximum adsorption of dye (44.24 mg/g) with good correlation coefficient (r2 = 0.980) while Freundlich isotherm showed a high correlation coefficient (r2 = 0.994) with value of n greater than unity (n = 1.27). The present study showed that Acutodesmus obliquus strain PSV2 is an eco friendly and highly efficient adsorbent for removal of acid red 66 dye from dyeing and textile industrial wastewater.Item Recovery and Recycling of Zn(II) from Wastewater by Scenedesmus sp. MCC 26 Isolated from a Heavy Metal Contaminated Site(Wiley, 2013) Verma, Sanjay KumarThis study evaluated the potential of Scenedesmus sp. MCC 26 as a new cost effective and efficient alternative for removing Zn(II) ions from viscose industrial effluent. Scenedesmus sp. MCC 26 (green microalgae) was isolated from a metal contaminated site and investigated for biosorption of Zn(II) from simulated viscose industrial effluent. Different biosorption parameters such as effect of pH (2–7), initial Zn(II) ion concentration (0–600 mg/L) and contact time (0–120 min) were investigated in order to optimize the process. The maximum absorption (142.85 mg/g) by the microalgal biomass was observed at pH 6 within 60 min of contact time at 28°C. Biosorption process was found to be rapid (6mg of Zn/g biomass per min) for initial 10 min followed by a slower phase (0.6mg of Zn/g biomass per min). The absorption data fitted well with Langmuir isotherm (qmax¼142.85 mg/g, r2¼0.973) and Freundlich isotherm (kf¼1.447, r2¼0.992). Treatment of Zn(II) loaded biomass with 0.1M H2SO4 showed almost 99% recovery of zinc which can be reused in the industrial processes. After first cycle of Zn(II) removal and recovery, the same biomass was tested for its reusability in repeated cycles. The results showed that the same biomass can be used minimum for five cycles of Zn(II) absorption and recovery with similar efficiency.Item The static extraction of lipid from microalgae Desmodesmus sp. MCC34(WRA, 2016) Verma, Sanjay KumarThe commonly used techniques for extraction of lipids from dry or wet biomass involve energy intensive steps such as cell lysis, high temperature and cell mixing causing substantial energy burden on the process. In present work, we report our finding on using a static method of mixing standard solvent with dry algal biomass without stirring. This extraction procedure was found to depend on the ratio of solvent volume to the biomass (SBR) and surface area factor (SAF). The kinetic study suggests that the static extraction followed Patricelli model of bi-phasic lipid extraction, consisting of a rapid washing step followed by the diffusion step. The results also suggest that the rate of lipid extraction in static process at optimum SBR and SAF, matched the rate of extraction obtained when lysed biomass was used or in the case where biomass was mixed (stirred) with solvent.Item Co-production of biodiesel and alpha-linolenic acid (omega-3 fatty acid) from microalgae, Desmodesmus sp. MCC34(Taylor & Francis, 2018-08-27) Verma, Sanjay KumarMicroalgae are a potential source of biofuel and nutraceuticals. In the present study, Desmodesmussp. MCC34 was identified as a promising species for biodiesel and omega-3 fatty acid productions after initial screening since it had displayed the highest lipid productivity of 15.9 mg L−1 day−1 and alpha-linolenic acid of 24% of total fatty acids. Using silver ion chromatography, 92% of pure alpha-linolenic acid was selectively removed from total lipid of Desmodesmussp. MCC34, while the residual oil having a higher amount of saturated and monounsaturated fatty acids displayed biodiesel property adhering to international standards, suggesting fuel co-application.Item Direct saponification of wet microalgae by methanolic potassium hydroxide using acetone as co-solvent(Elsiever, 2019-02) Verma, Sanjay KumarThe fatty acids of microalgae are promising source of biodiesel and omega-3 fatty acids. The objective of this study is extraction of fatty acids from wet Dunaliela salina by direct saponification using methanolic potassium hydroxide and a suitable co-solvent. The study identified acetone as an efficient co-solvent for saponification of wet microalgal biomass by methanolic potassium hydroxide. The presence of acetone in methanolic KOH saponification produced 24% more fatty acid than its absence. Further optimization of concentration of acetone (80% v/v), concentration of potassium hydroxide (0.1% v/v) and solvent-dry biomass ratio (75:1) resulted in a maximum yield of 98% fatty acid. The proposed acetone assisted saponification of wet microalgal biomass could serve as an energy efficient route for fatty acid production since the reaction happens under room temperature and normal atmospheric pressure without any cell lysis or drying the biomass.