PERFORMANCE STUDY OF KEMBOJA GUM LIPASE (PLUMERIA RUBRA) FOR STEARIC ACID ESTERIFICATION

• Main Author: Wulansari, Apriyani
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/83324
• Institution: Institut Teknologi Bandung

Glycerol monostearate (GMS) is a non-ionic amphoteric monoglyceride used widely in the food, pharmaceutical, and cosmetic sectors, mainly functioning as an emulsifier. The production of Glycerol monostearate can be achieved through esterification and transesterification methods. Both of these pathways can be performed using chemical catalysts, biocatalysts, or even no catalyst at all. Conventional methods, characterised by high temperatures, often result in dark colours and the formation of unwanted by-products such as diglycerides and triglycerides. An alternative approach involves a biocatalytic route using vegetable-derived lipase enzymes sourced from frangipani gum at moderate temperatures. Lipase was chosen due to its good selectivity in synthesising individual fatty acids, while tert-butyl alcohol was used as the reaction medium to exclusively produce monoglyceride products without diglyceride formation. The esterification process was carried out at atmospheric pressure, using molar ratios of stearic acid to glycerol ranging from 1:1 to 1:10. The temperature range used during the reaction was 30?80°C, reaction time 1?7 h, using lipase sourced from frangipani gum at amounts ranging from 2?20% by weight to stearic acid, stirring speed ranging from 150?900 rpm and tert-butanol solvent. Translated with DeepL.com (free version)Following the esterification reaction, the acid number exhibited a decrease from 198,387 mg KOH/gr sample to 50,22 mg KOH/gr sample, indicating the successful conversion of stearic acid and glycerol into glycerol monostearate.