Kajian Hidrolisis Enzimatik Minyak Ikan untuk Produksi Omega-3 Menggunakan Lipase dari Aspergillus niger pada Media yang Ditambahkan Heksana.
Abstract
Nowadays utilization of sea fish is limited for human consumption only. This is made solid waste and fish oil that is produced during the process could not be utilized further. Besides, fish oil is the source of important fatty-acid, especially polyunsaturated fatty acid (PUFA) omega-3, those are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). These kinds of fatty acids have important roles in fulfilling human nutrition, preventing and curing few diseases. Omega-3 fatty acid in acylglycerol form is considered better as food chemical form because it is digested easily by human digestive system. Production of omega-3 fatty acid in acylglycerol form with high products could be reached through enzymatic hydrolysis reaction. Aspergillus niger lipase has positional specificity that could break down triacylglycerols chain on stereochemical numbering position (sn) 1 and 3. Usage of this lipase in hydrolysis reaction could produce a lot of omega-3 fatty acid, especially eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Catalytic activity of Aspergillus niger lipase is low when it is used in hydrolysis reaction of fish oil. That is the reason that it is needed to find a way to increase catalytic activity of Aspergillus niger lipase by adding organic solvent of hexane into its hydrolysis media. Besides, during hydrolysis process, activity and stability of enzyme is affected by environment condition, such as temperature, pH and water addition. This research had aim to determine reaction factor condition that could produce highest degree of hydrolysis of fish oil in a media without or with added-hexane media. Besides, this research aim was to determine the correlation between highest degree of hydrolysis of fish oil and sum amount of omega-3 fatty acid. The variation of factor reaction that was used here were temperatures (25-65)oC, pH (5-9), and water addition (1-5)%v/v. This research stage was began with fish oil characterization, measurement of activity of Aspergillus niger lipase with spectrofotometri method, enzymatic hydrolysis of fish oil in media without solvent addition, and hydrolysis in media with solvent addition using optimum temperature and pH from the result of hydrolysis in media without hexane addition. Analysis of end product was included measurement of degree of hydrolysis and gas chromatography mass spectrometry (GC-MS) analysis. Results of fish oil characterization of physiochemical characteristic showed that it had acid value of 3,26 mg KOH/g, free fatty acid content of 1,49%, and saponification value of 204,81 mg KOH/g. On the other hand, results of fish oil characterization of component analysis showed that it had saturated fatty acid content of 23,2%, unsaturated fatty acid content of 34,98%, alkenes 11,19%, squalenes 4,75%, aldehide 0,88% and lanol 24,96%. Result of measurement of activity of Aspergillus niger lipase was 7939,97 U/g.