Candida rugosa lipase nanoparticles as robust catalyst for biodiesel production in organic solvents

Abstract

rugosa lipase nanoparticles as robust catalyst for biodiesel production in organic solvents.Inexpensive but resourceful sources of lipids, for example, used cooking oil (UCO) and brown grease (BG), which often contain large amounts of free fatty acids (FFA), are difficult to convert into biodiesel economically and in good yield. Candida rugosa lipase nanoparticles (cNP) were formed first and subsequently cross-linked nanoparticles (CLNP) were obtained by crosslinking of them. Alternatively, cNP were conjugated to magnetic nanoparticles (mNP) to achieve a cNP-mNP conjugate. All three formulations were employed in three different organic solvents (n-heptane, 1,4-dioxane, and t-butanol) to produce biodiesel using BG and UCO in the transesterification reaction with ethanol and methanol. The radii of nanoparticles (NP) were 5.5, 75, 100, 85 nm for mNP, cNP, CLNP, and cNP-mNP, respectively, as measured by scanning/transmission electron microscopy and dynamic light scattering. The catalytic efficiency (Kcat/KM) of cNP, CLNP, and cNP-mNP was increased ca. -25, -68, -176 folds in n-heptane and -35, -131, -262 folds in 1,4-dioxane compared to the lyophilized lipase in the model transesterification reaction of p-nitrophenyl palmitate (PNPP) with ethanol. In biodiesel formation, the best performance with 100% conversion of BG was achieved under optimum conditions with cNP-mNP, ethanol at a 1:3 molar ratio of lipid-to-alcohol, NP at a 1:0.1 weight ratio of lipid-to-enzyme, and water at a 1:0.04 weight ratio of enzyme-to-water at 30 o C for 35 h. The operational stability of the CLNP and cNP-mNP was sustained even after five consequent biodiesel batch conversions while 50% and 82% residual activity (storage stability) were retained after 40 d.

Optimizing the catalytic activities of methanol and thermotolerant Kocuria flava lipases for biodiesel production from cooking oil wastes

“…Recently, several studies have been focused on the use of nanostructures including, nanofibers, nanocarbon and magnetic nanoparticles were for many biomedical applications 35 as well as for supporting enzyme immobilization 36 . Sharma et al 37 investigated the efficacy of Candida rugosa lipase nanoparticles as a biocatalyst for biodiesel syntheses using free fatty acid-rich waste lipid sources (used cooking oil and brown grease). The obtained results from Candida rugosa lipase nanoparticles as a biocatalyst revealed the high performance of nanoparticles for biodiesel production which may be attributed to the inclusion of methyl-β-cyclodextrin subsequently their crosslinking and conjugation, which providing enhancement of lipase enzyme activity and stability 37 .…”

“…Sharma et al 37 investigated the efficacy of Candida rugosa lipase nanoparticles as a biocatalyst for biodiesel syntheses using free fatty acid-rich waste lipid sources (used cooking oil and brown grease). The obtained results from Candida rugosa lipase nanoparticles as a biocatalyst revealed the high performance of nanoparticles for biodiesel production which may be attributed to the inclusion of methyl-β-cyclodextrin subsequently their crosslinking and conjugation, which providing enhancement of lipase enzyme activity and stability 37 . Additionally, a new technology, based on ultrasound application, has been employed for the improvement of enzymatic transesterification and enzymatic esterification processes for biodiesel production that may enhance oil dissolution, increase conversion rate, and prompt protein conformational changes that may enhance enzymatic catalytic activities 38 .…”

Environmentally benign solid catalysts for sustainable biodiesel production: A critical review

“…Despite years of development, the design of catalytic processes to manufacture FAMEs and FAEEs is still challenging (Banga and Varshney, 2010;Meira et al, 2015). Catalysts play a very important role in transesterification of vegetable oils or fats (Aderibigbe et al, 2020;Sharma et al, 2019). Developing efficient and low cost catalysts with an environmentally friendly approach is essential in order to resolve the current problems in homogeneous and heterogeneous chemical catalysts such as high cost, reusability, separation difficulty, poisoning and leaching.…”