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Solvent-tolerant lipase produced by Bacillus sp. DM9K3 has been isolated from the hypersaline area, White Rann of Kachchh, Gujarat, India. The strain initially showed lipase activity of 11.1 U/mL in a basal medium which increased to 52.0 U/mL under optimized culture conditions. Bacillus sp. DM9K3 exhibited stability at 7% salinity, pH 9.0 and 50°C. The extracellular lipase was partially purified by acetone precipitation followed by DEAE-cellulose resulting in 39-fold purification with 40% yield. Metals ions such as Mg2+, Ca2+ and K+ showed enhanced enzyme activity. EDTA did not have a significant effect on activity suggesting that lipase is not metalloenzyme. The lipase under study showed the highest activity when palmitate (C16) was used as a substrate and was also highly stable in organic solvents such as cyclooctane and benzene. The partially purified enzyme was immobilized for increasing the efficiency of the ethyl caprylate (an orange flavored ester) synthesis in the presence of cyclooctane. Additionally, lipase of Bacillus sp. DM9K3 was explored for biodegradation of polycaprolactone microspheres and showed promising results for potential applications in drug delivery system. [ABSTRACT FROM AUTHOR]

Abstract In this study, Penicillium sp. section Gracilenta CBMAI 1583 was used to produce lipase under submerged conditions. The enzyme was purified and the biochemical properties of both the crude and purified enzymes were evaluated. Maximum lipase production (1.62 U mL−1) was obtained using olive oil 0.5% (w v−1) after 72 h of cultivation, representing a 90% increase in the lipase initially produced. The enzyme was purified using hydrophobic interaction chromatography (phenyl Sepharose) under conditions which allowed its interfacial activation. The partially purified sample showed an enzyme with esterase activity (65.4 kDa) on α- and β-naphthyl acetate and other with lipase activity (52.9 kDa) on octyl oleate. Optimum activity of crude and purified lipase was observed at pH 4.0 and 70 °C. The purified lipase was activated by NaCl, BaCl 2 , NH 4 Cl, MnSO 4 and MgSO 4 ; it also presented high stability in organic solvents such as hexane, 2.2.4-trimethylpentane, acetone, DMSO and toluene. Maximum enzyme activity was observed with p -nitrophenyl decanoate as substrate; and the enzyme kinetics showed to be directly affected by Triton X-100. The enzyme shows potential application in processes that operate in acid pH, such as treatment of dairy and industry effluents, resolution of esters in the pharmaceutical industry or in the food industry, as well in synthesis reaction under non-aqueous conditions. Highlights • Lipase from Penicillium sp. Section Gracilenta was produced first time with olive oil. • Partial purification showed two lipolytic enzymes such as esterase and lipase. • Interfacial technique provide purified lipase with 52.9 kDa. • Crude and purified lipases showed be thermotolerant enzymes. • Stability in organic solvents suggests it uses in reactions in non-aqueous media. [ABSTRACT FROM AUTHOR]

The present study describes the characteristics of a thermotolerant and alkaline lipase secreted by Pseudomonas sp. BUP6, a novel rumen bacterium isolated from Malabari goat, and its trans-esterification efficiency in producing biodiesel from used cooking oil (UCO). The extracellular lipase was purified to homogeneity (35.8 times purified with 14.8% yield) employing (NH)SO salt precipitation and Sephadex G-100 chromatography. The apparent molecular weight of this lipase on SDS-PAGE was 35 kDa, the identity of which was further confirmed by MALDI-TOF/MS. The purified lipase was found stable at a pH range of 7-9 with the maximum activity (707 U/ml) at pH 8.2; and was active at the temperature ranging from 35 to 50 °C with the optimum at 45 °C (891 U/ml). Triton X-100 and EDTA had no effect on the activity of lipase; whereas SDS, Tween-80 and β-mercaptoethanol inhibited its activity significantly. Moreover, Ca (1.0 mM) enhanced the activity of lipase (1428 U/ml) by 206% vis-à-vis initial activity; while Zn, Fe and Cu decreased the activity significantly. Using para-nitrophenyl palmitate as substrate, the K (11.6 mM) and V [668.9 μmol/(min/mg)] of the purified lipase were also determined. Crude lipase was used for analyzing its trans-esterification efficiency with used cooking oil and methanol which resulted in the worthy yield of fatty acid methyl esters, FAME (45%) at 37 °C, indicating its prospects in biodiesel industry. Thus, the lipase secreted by the rumen bacterium, Pseudomonas sp. BUP6, offers great potentials to be used in various industries including the production of biodiesel by trans-esterification. [ABSTRACT FROM AUTHOR]

A gene encoding a thermotolerant lipase with broad pH was isolated from an Antarctic Pseudomonas strain AMS3. The recombinant lipase AMS3 was purified by single-step purification using affinity chromatography, yielding a purification fold of approximately 1.52 and a recovery of 50%. The molecular weight was approximately ∼60 kDa including the strep and affinity tags. Interestingly, the purified Antarctic AMS3 lipase exhibited broad temperature profile from 10–70 °C and stable over a broad pH range from 5.0 to pH 10.0. Various mono and divalent metal ions increased the activity of the AMS3 lipase, but Ni2+ decreased its activity. The purified lipase exhibited the highest activity in the presence of sunflower oil. In addition, the enzyme activity in 25% v/v solvents at 50 °C particularly to n-hexane, DMSO and methanol could be useful for catalysis reaction in organic solvent and at broad temperature.