Kaffir lime oil has many health benefits. However, an obstacle to its commercial use is oxidation during storage. Nanoemulsions (particulate colloidal systems) have been shown to be suitable carriers for lipophilic essential oil constituents due to amphipathic compounds that facilitate solubility. The objectives of this study were to formulate thermodynamically stable kaffir lime oil nanoemulsions and to investigate their physicochemical properties. Air-dried leaves of kaffir lime were subjected to steam distillation to obtain essential oil. Preparation of nanoemulsions was done using the spontaneous emulsification method. Tween 80 and propylene glycol were selected as surfactant mix components. The oil phase consisted of Miglyol 812 as a carrier oil for kaffir lime oil while double-distilled water was used in the aqueous phase. The best formula with transmittance above 95% and highest essential oil content was selected. It contained 20% of Tween 80, 10% of propylene glycol, 1.25% Miglyol 812, and 3.75% kaffir lime essential oil. This formula was then characterized and its thermodynamic stability determined. . The results showed that kaffir lime oil nanoemulsions were thermodynamically stable and robustly withstood variations in temperature, centrifugation, and long-term storage. Additionally, the nanoemulsions had low viscosity, which may facilitate its development as a pharmaceutical compound.

Our previous study showed that kaffir lime leaf extracts may have anticancer properties. However, production of bioactive compounds is affected by environmental factors. Here, we present a method to control environmental conditions using in vitro culture techniques such as callus induction. Calluses were induced from seed embryo explants of kaffir lime on MS medium with combinations of 2,4-D and BAP at concentrations 1:0.5; 1:1; and 2:1, respectively. Fourty and 60 days-old calluses were extracted using chloroform and ethyl acetate and analyzed by GC-MS. Results showed all combinations of 2,4-D and BAP were able to induce callogenesis from seed embryo explants of kaffir lime with no significant differences of callus initiation time, biomass, morphology and growth rates. However differences were detected in the bioactive compound profiles. In kaffir lime callus, both fatty acids and secondary metabolites were detected. Specifically, in 40 daysold calluses (exponential growth phase) we detected α-pinene and 1.8cineole in plants treated with 2,4-D: BAP at concentration 1:0.5 and 2:1. In 60 days-old calluses (stationary phase) we detected a number of compounds in plants treated with 2,4-D:BAP at concentrations of 1:0.5 and 2:1, including

Cellulase has been widely used as biocatalyst in industries. Production of cellulase from microorganisms has many advantages such as short production time and less expense. Our previous study indicated that one of cellulolytic bacteria from digestive tract of milkfi sh (Chanos chanos), namely BSA B1, showed the highest cellulase activity. The objective of this study was to determine the phylogenetic of BSA B1 strain using 16S rRNA gene sequence. Furthermore, this study also determine the specifi c activity of purifi ed cellulase from BSA B1 strain and its potency to hydrolyze Chlorella zofi ngiensis cellulose. Cellulase was purifi ed using ammonium sulphate precipitation, dialysis, and ion exchange chromatography. The purifi ed cellulase was used to hydrolyze cellulose of C. zofi ngiensis. The result demonstrated that BSA B1 strain was closely related with Bacillus aerius and Bacillus licheniformis. The specifi c activity of the crude enzyme was 1.543 U mL -1 ; after dialysis was 4.384 U mL -1 ; and after chromatography was 7.543 U mL -1. Purifi ed cellulase exhibited activity in hydrolyzed both CMC and C. zofi ngiensis. Compared to commercial cellulase, purifi ed cellulase had lower activity in hydrolyzed CMC but higher activity in hydrolyzed C. zofi ngiensis. Ethanol dehydration could potentially increase the reducing sugar yield in cellulose hydrolysis when used appropriately. Morphology of C. zofi ngiensis cell has changed after incubation with cellulases and ethanol dehydration indicated degradation of cell wall.

The addition of elicitors in kaffir lime (Citrus hystrix DC.) culture is one of  strategies for obtaining and increasing the production of secondary metabolites.  Saccharomyces cerevisiae is one of the elicitors that can be used to increase secondary metabolites such as terpenoids. However, in its use, the pure cultures of S. cerevisiae are expensive. Therefore, the first objective of this study was to analyze the ability of technical grade (commercial baker’s yeast) to be used as an elicitor and measure the growth of kaffir lime cell line after being elicited by pure and technical grade (commercial baker’s yeast). The second objective is to determine the best time to subculture kaffir lime cell line after elicitation. We observed the morphology and measured the growth curve of pure and technical grade yeast until the 4th subculture generation. Furthermore, we used both grades of yeast for elicitation. Kaffir lime cell suspension was treated with 10 ppm pure grade or 5 ppm and 10 ppm technical grade yeast for 4 days. After elicitation, kaffir lime cell lines were subcultured and their growth was analyzed. The result showed that the morphology and growth curve of technical grade until 4th subculture generations was similar to the pure grade. On the other hand, after elicitation using pure and technical grade yeast and being subcultured, the growth of the elicitated kaffir lime cell line had the same pattern as the control group, but the cell density of the control group was higher than the elicitated group. The initial stationary phase of kaffir lime cell line was on the 17th day which is the best time to subculture. The subculturing process is important to maintain the viability of the kaffir lime cell line.