An alternative method for production of microalgal biodiesel using novel Bacillus lipase

Abstract

In this study, enzymatic interesterification is carried out using encapsulated lipase as biocatalyst with methyl acetate as acyl acceptor in a solvent-free system. Lipase, isolated from a marine bacterial isolate, Bacillus sp.S23 (KF220659.1) was immobilized in sodium alginate beads. This investigation elaborated on the effects of various parameters, namely enzyme loading, temperature, water, molar ratio, reaction time and agitation for interesterification. The study resulted in the following optimal conditions: 1.5 g immobilized lipase, 1:12 molar ratio of oil to methyl acetate, 35 °C, 8 % water, 60 h reaction time, 250 rpm of agitation. With the standardized condition, the maximum conversion efficiency was 95.68 %. The immobilized beads, even after ten cycles of repeated usage showed high stability in the presence of methyl acetate and no loss of lipase activity. The microalgal biodiesel composition was analyzed using gas chromatography. The current study was efficient in using immobilized lipase for the interesterification process, since the method was cost-effective and eco-friendly, no solvent was involved and the enzyme was encapsulated in a natural polymer.

Biosynthesis of silver nanoparticle and its application in cell wall disruption to release carbohydrate and lipid from C. vulgaris for biofuel production

“…Many pretreatment methods can be used for microalgal cell disruption such as physical treatment including ultrasonication [14] , [17] , thermal [13] , [18] , microwave [13] , [14] , [19] , bead milling [14] , [20] and cryogrinding [13] , [21] , chemical methods including acid [22] , [23] , alkaline [24] , solvent soaking [21] and osmotic shock [13] and enzymatic treatments [10] , [25] , [26] , [27] , [28] . Nevertheless, these methods have some limitations; physical or mechanical methods are not effective and not suitable for large-scale operations [27] , chemical methods cause pollution [29] and also destruct other cellular components [27] , and enzymatic treatment is cost intensive and very slow process [17] .…”

Warm and wet: robust lipase-producing bacteria from the indoor environment

“…Bacillus sp. have been previously reported to produce thermostable lipases [28,29,30,31]. Regarding the Bacillus species that we have isolated and identified in the present work, they are known to produce thermo-resistant lipases, some of them stable at very low or very high pH values.…”

The radius of influence of a combined method of in situ air sparging and soil vapor extraction in the intertidal sediments of Gomso Bay on the west coast of South Korea

“…Within ROI, oxygen can potentially be transferred to resident microorganisms participating in biological degradation processes (Surendhiran et al 2015 ; Chikere et al 2011 ; US Army corps of Engineers 2002 ). The radius of oxygen transference is the maximum distance of the transference of oxygen in air injected through injection wells for biological degradation of contaminants.…”