20 research outputs found

    Enzymatic transesterification of Jatropha oil

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    <p>Abstract</p> <p>Background</p> <p>Transesterification of Jatropha oil was carried out in t-butanol solvent using immobilized lipase from <it>Enterobacter aerogenes</it>. The presence of t-butanol significantly reduced the negative effects caused by both methanol and glycerol. The effects of various reaction parameters on transesterification of Jatropha oil were studied.</p> <p>Results</p> <p>The maximum yield of biodiesel was 94% (of which 68% conversion was achieved with respect to methyl oleate) with an oil:methanol molar ratio of 1:4, 50 U of immobilized lipase/g of oil, and a t-butanol:oil volume ratio of 0.8:1 at 55°C after 48 h of reaction time. There was negligible loss in lipase activity even after repeated use for seven cycles.</p> <p>Conclusion</p> <p>To the best of our knowledge this is the first report on biodiesel synthesis using immobilized <it>E. aerogenes </it>lipase.</p

    Sustainable Utilization of Renewable Plant – Based Material for the Green Synthesis of Metal Nanoparticles

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    Despite the fact that biotechnology and nanotechnology have been developed for ages to assist vastly different domains including medical, industry, human health, and welfare, they have achieved impressive strides recently. The creation of metallic nanoparticles (NPs) quickly, sustainably, and without toxicity is crucial for the field of nanobiotechnology. An emerging field is the synthesis of metallic NPs (AgNPs, AuNPs, PtNPs, PdNPs, SeNPs, CuNPs, MgONPs etc.) using biological systems, particularly plants. Plant tissues, extracts, extrude, and other plant parts have all been widely employed to make metallic nanoparticles. If plant-based NPs are created extracellularly and their size, shape, and dispersion are managed, the benefit of using them can be exponentially ramped up. In order to produce nanoparticles on a large scale industrially, it is suggested that “green” synthesis of nanoparticles be a feasible prospect. This is because it is extremely very cost-effective. Plant-based NPs have identified a niche to demonstrate their application in every area of research, including agriculture, health, and the solution to the world’s energy dilemma. In this light, the current chapter makes an effort to emphasis the environmentally friendly methods of “green” nanomaterial synthesis, characterization, and applications across different industries

    Sinteza izoamilnog acetata pomoću lipaze u sustavu bez otapala s vinilnim acetatom kao donorom acila

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    Synthesis of isoamyl acetate, a flavour ester extensively used in food industry, has been carried out in a solvent-free system. In the present study, an attempt has been made to enhance the isoamyl acetate synthesis yield by transesterification of isoamyl alcohol with vinyl acetate using immobilized Rhizopus oryzae NRRL 3562 lipase. In the present synthesis, substrates had no inhibitory effect on immobilized lipase. The effects of various reaction parameters on isoamyl acetate synthesis were studied and maximum conversion was achieved at 16 % (by mass per volume) of immobilized lipase, 40 °C and 200 rpm. Under these conditions, 8-hour reaction time was sufficient to reach a high ester conversion of 95 % with 0.5 mol/L of isoamyl alcohol. The structure of the transesterified product was confirmed by infrared and nuclear magnetic resonance spectroscopic studies. Immobilized lipase had Km and vmax values of 306.53 mmol/L and 99 µmol/(h·g) respectively, for isoamyl acetate synthesis in a solvent-free system.Provedena je sinteza izoamilnog acetata, estera koji se često koristi kao pojačivač okusa u prehrambenoj industriji, u sustavu bez otapala. Pokušao se poboljšati prinos izoamilnog acetata transesterifikacijom s vinilnim acetatom pomoću imobilizirane lipaze izolirane iz soja Rhizopus oryzae NRRL 3562. Pri tome supstrat nije inhibirao imobiliziranu lipazu. Istražen je utjecaj različitih parametara reakcije na sintezu te ustanovljeno da je maksimalna pretvorba postignuta sa 16 % (m/V) imobilizirane lipaze pri 40 °C i 200 rpm. Pri tim je uvjetima nakon 8 sati postignuta 95 %-tna konverzija s 0,5 mol/L izoamilnog acetata. Struktura produkta utvrđena je infracrvenom spektroskopijom i nuklearnom magnetskom rezonancijom. Imobilizirana lipaza imala je Km vrijednost od 306,53 mmol/L i υmax od 99 µmol/(h∙g)

    Impact of land-use changes on soil properties and carbon pools in India: A meta-analysis

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    Not AvailableLand-use changes (LUC), primarily due to deforestation and soil disturbance, are one of the major causes of soil quality degradation and greenhouse gas emissions. Effects of LUC on soil physicochemical properties and changes in soil quality and land use management strategies that can effectively restore soil carbon and microbial biomass levels have been reported from all over the world, but the impact analysis of such practices in the Indian context is limited. In this study, over 1,786 paired datasets (for meta-analysis) on land uses (LUs) were collected from Indian literature (1990–2019) to determine the magnitude of the influence of LUC on soil carbon, microbial biomass, and other physical and chemical properties at three soil depths. Meta-analysis results showed that grasslands (36.1%) lost the most soil organic carbon (SOC) compared to native forest lands, followed by plantation lands (35.5%), cultivated lands (31.1%), barren lands (27.3%), and horticulture lands (11.5%). Our findings also revealed that, when compared to forest land, the microbial quotient was lower in other LUs. Due to the depletion of SOC stock, carbon dioxide equivalent (CO2 eq) emissions were significantly higher in all LUs than in forest land. Results also showed that due to the conversion of forest land to cultivated land, total carbon, labile carbon, non-labile carbon, microbial biomass carbon, and SOC stocks were lost by 21%, 25%, 32%, 26%, and 41.2%, respectively. Changes in soil carbon pools and properties were more pronounced in surface (0–15 cm) soils than in subsurface soils (15–30 cm and 30–45 cm). Restoration of the SOC stocks from different LUs ranged from a minimum of 2% (grasslands) to a maximum of 48% (plantation lands). Overall, this study showed that soil carbon pools decreased as LUC transitioned from native forestland to other LUs, and it is suggested that adopting crop-production systems that can reduce CO2 emissions from the intensive LUs such as the ones evaluated here could contribute to improvements in soil quality and mitigation of climate change impacts, particularly under Indian agro-climatic conditions.Not Availabl

    Lipase Mediated Isoamyl Acetate Synthesis in Solvent-Free System Using Vinyl Acetate as Acyl Donor

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    Synthesis of isoamyl acetate, a flavour ester extensively used in food industry, has been carried out in a solvent-free system. In the present study, an attempt has been made to enhance the isoamyl acetate synthesis yield by transesterification of isoamyl alcohol with vinyl acetate using immobilized Rhizopus oryzae NRRL 3562 lipase. In the present synthesis, substrates had no inhibitory effect on immobilized lipase. The effects of various reaction parameters on isoamyl acetate synthesis were studied and maximum conversion was achieved at 16 % (by mass per volume) of immobilized lipase, 40 °C and 200 rpm. Under these conditions, 8-hour reaction time was sufficient to reach a high ester conversion of 95 % with 0.5 mol/L of isoamyl alcohol. The structure of the transesterified product was confirmed by infrared and nuclear magnetic resonance spectroscopic studies. Immobilized lipase had Km and vmax values of 306.53 mmol/L and 99 µmol/(h·g) respectively, for isoamyl acetate synthesis in a solvent-free system

    Lipase mediated isoamyl acetate synthesis in solvent-free system using vinyl acetate as acyl donor

    No full text
    Synthesis of isoamyl acetate, a flavour ester extensively used in food industry, has been carried out in a solvent-free system. In the present study, an attempt has been made to enhance the isoamyl acetate synthesis yield by transesterification of isoamyl alcohol with vinyl acetate using immobilized Rhizopus oryzae NRRL 3562 lipase. In the present synthesis, substrates had no inhibitory effect on immobilized lipase. The effects of various reaction parameters on isoamyl acetate synthesis were studied and maximum conversion was achieved at 16 % (by mass per volume) of immobilized lipase, 40 °C and 200 rpm. Under these conditions, 8-hour reaction time was sufficient to reach a high ester conversion of 95 % with 0.5 mol/L of isoamyl alcohol. The structure of the transesterified product was confirmed by infrared and nuclear magnetic resonance spectroscopic studies. Immobilized lipase had Km and vmax values of 306.53 mmol/L and 99 μmol/(h·g) respectively, for isoamyl acetate synthesis in a solvent-free system
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