OPTIMIZATION DOWNSTREAM PROCESS OF INTRACELLULAR LIPID PRODUCTION FROM RHODOTORULA TORULOIDES

• Main Author: Dafa Ghifari Alparisi, Muhammad
• Format: Final Project
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/83008
• Institution: Institut Teknologi Bandung

Intracellular lipids from oleaginous yeast are important biomolecules in modulating vital cellular functions. The production of intracellular lipids from oleaginous yeast species Rhodotorula toruloides starts from upstream stages including cell cultivation to downstream stages including cell harvesting, cell disruption, and cell extraction. The complex and relatively resistant cell wall of yeast limits the extraction of intracellular lipids, therefore the downstream process before the extraction stage, namely cell harvesting and pre-treatment, needs to be optimized to streamline the release of intracellular lipids. Rhodotorula toruloides is one of the oleaginous yeast species, which is a yeast capable of synthesizing lipids with a total lipid accumulation of more than 20% of its dry cells. Each microbial species such as Rhodotorula toruloides has its own uniqueness and differences so that the downstream process strategy in lipid production needs to be determined and optimized for lipid production. Therefore, this study aims to optimize the cell harvesting process from the centrifugation duration and drying method and optimize the acid hydrolysis process by varying the concentration of HCl which is part of the downstream process. The results showed that for optimization of centrifugation duration, the optimum condition was obtained at a duration of 60 minutes with the lowest water loss value of 78.633% and the highest cell dry weight of 0.072 g from 5 ml of cultivation samples. For optimization of the drying method, the optimum condition was obtained using the freeze drying method with the acquisition of intracellular lipids of 55.44% g lipid/g dry sample with a dry sample weight of 1.012g. For optimization of HCl concentration in cell disruption using acid hydrolysis method, the optimum condition was obtained using 25% HCl concentration with a lipid gain of 55.67% for freeze drying method and 52.45% for drying using 80o C vacuum oven. For fatty acid profile analysis, the combination of optimization treatments (60 min centrifugation duration, freeze drying, and 25% HCl concentration for cell disruption) gave the highest fatty acid profile values with profiles of C16:0 (Palmitic Acid), C18:1 (Oleic Acid), C18:2 (Linoleic Acid), Omega-6 fatty acids, Omega-3 fatty acids respectively at 15.85%; 29.98%; 5.22%; 5.23%; and 1.21% of 10 mL lipid samples.