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Lipase‐catalyzed esterification and properties of synthesized carbohydrate esters were investigated. Methyl α‐d‐glucopyranoside was the acyl group acceptor and different carbon atom chain lengths of aliphatic carboxylic acids (C12, C14 and C16) as the acyl group donors were applied in the esterification. Physico‐chemical studies on the synthesized carbohydrate esters were carried out. It was found that melting point for the methyl 6‐O‐hexadecanoyl‐α‐d‐glucopyranoside was the highest consecutively followed by methyl 6‐O‐tetradecanoyl‐α‐d‐glucopyranoside and methyl 6‐O‐dodecanoyl‐α‐d‐glucopyranoside. Liquid crystal properties of the synthesized carbohydrate ester synthesized were evaluated via optical polarized microscopy. It was found that the liquid crystal textures for mono‐substituted carbohydrate esters were of the smectic phase. In a quaternary system (carbohydrate ester/n‐butanol/n‐hexadecane/water), a maximum 34 % of water (by mass) was contained in the monophasic region of methyl 6‐O‐tetradecanoyl‐α‐d‐glucopyranoside and a maximum of 52 % water (by mass) was contained in a monophasic methyl 6‐O‐dodecanoyl‐α‐d‐glucopyranoside. For methyl‐6‐O‐dodecanoyl‐α‐d‐glucopyranoside, its concentration at aggregation was 5.2 × 10−4 mM, with minimum air/water surface tension of 26 mN m−1. The Gibbs energy of micellization was calculated at −50 kJ mol−1. The maximum adsorption density of methyl 6‐O‐dodecanoyl‐α‐d‐glucopyranoside was determined at 4 × 10−6 mol m−2 while its minimum area per surfactant molecule at the air/water surface was 47 Å2.

Nanomaterial-based biocatalysts have emerged as current carriers suitable for enzyme immobilization. The nano-sized materials provide large surface area for enzyme attachment, thus increasing the probability for its efficient catalyst activity. By using magnetized nanomaterials, enhancement of the downstream processing is evident as it eases the immobilized enzyme separation from the reaction mixture further. Lipase / maghemite composites were prepared by initial maghemite surface modification to cater to the needs for biocatalyst attachment. Surface modification using chitosan and subsequent cross-linking with glutaraldehyde provide a suitable environment for the enzyme to be immobilized. Optimization of the conditions for lipase immobilization was carried out using a response surface methodology (RSM) experimental design to obtain the precise optimized conditions for the process. Selected process variables involved were chosen and optimized conditions for lipase immobilization were 9 hour incubation time, 55°C incubation temperature and 12 % (v/v) glutaraldehyde content. The optimized immobilized lipase activity was 1.8 U. Characterizations of the on synthesized materials were also performed. The size distribution of maghemite nanomaterials was mainly within the range of 2-3 nm. Thermal properties of the synthesized maghemite was investigated using DSC and TGA analyses and we found that maghemite changes to hematite at 456.3°C. Magnetic properties of both untreated and lipase immobilized maghemite were studied using VSM and both were superparamagnetic nanomaterials with saturation magnetizations of 34.3 and 80.3, respectively.