Judul: Kajian Hidrolisis Enzimatik Minyak Ikan untuk Produksi Omega-3 Menggunakan Lipase dari Aspergillus niger pada Media yang Ditambahkan Toluena
Abstrak: Omega-3 is an essential fatty acid that is needed for our brain and other organs development. Our body could not produce omega-3 itself, so we should consume it from our food. Omega-3 is found mostly from sea fish that eat phytoplankton that can produce omega-3 within their body. Many researches had been done to find an effective and efficient way to extract omega-3 from fish oil through hydrolysis, esterification, interesterification, acidolysis, or transesterification reaction. Omega-3 is usually produced in these three common forms: methyl ester, free fatty acid and acylglycerol. Acylglycerol form is considered better as food chemical material because it is easily digested by human digestive system. Selection of lipase as catalyst of hydrolysis reaction because of its easiness to get, it does not need cofactor, its stability and tolerance with solvent. Organic solvent could modify the original form of enzyme, so that it could change catalytic efficiency and specificity of enzyme. This research had aim to get reaction factor condition that could produce the best degree of hydrolysis of fish oil in a media without and with toluene-added media. Besides, this research’ aim was to figure out the correlation between optimum degree of hydrolysis of fish oil and sum amount of omega-3 fatty acid. The variations of factor reaction those were used here were temperatures (25-65)o Enzymatic hydrolysis of fish oil in this research was used a no-toluene-added media and a toluene-added media. Factors those were analyzed in hydrolysis in a no-toluene-added media are temperature and pH treatment. Factors those were analyzed in hydrolysis in a toluene-added media are water addition, pH and temperature treatment. Parameter that was used here to determine the effect of each factor was degree of hydrolysis. C, pH (5-9) and water addition (1-5)%v/v. Highest degree of hydrolysis in media without toluene addition on temperature treatment was 6,02% that was reached at 45o In water addition treatment, there were no significant effects of degree of hydrolysis for every stage of water addition. Otherwise, there was significance of degree of hydrolysis was decreasing. In pH treatment, degree of hydrolysis was decreasing while the value of pH was increasing. When it was reached pH 7, degree of hydrolysis had reached stationer phase for another stage of pH. C, while on pH treatment was 23,42% that was reached on pH 5. Highest degree of hydrolysis in media with toluene addition in a media with toluene addition on water addition treatment was 15,69%, while on pH treatment was 10,66% and on temperature treatment was 11,59%. According to the result of GC-MS analysis, highest omega-3 content was reached from enzymatic hydrolysis in a media without toluene addition on pH 5, whereas its EPA content was 12,43% and its DHA content was 0,86%. Omega-3 content in the result of enzymatic hydrolysis in a media with toluene addition consist of EPA content of 3,01% and DHA content undetected. Toluene addition into hydrolysis media could not increase the catalytic activity of Aspergillus niger lipase. So, it is better to hydrolyze fish oil with Aspergillus niger lipase in a no-toluene-added-media to reach higher degree of
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Judul: Kajian Hidrolisis Enzimatik Minyak Ikan Untuk Produksi Omega-3 Menggunakan Enzim Lipase Aspergillus niger Pada Media Yang Ditambahkan Heptana.
Abstrak: Nowadays, the processing of sardine fish was as canned fish. The Waste was solid waste and fish oil which discarded and unusable further. However, this waste contains Omega-3. Omega-3 fatty acids were considered of essential for normal growth. It might be an important role to in the prevention and treatment of coronary artery disease, hypertension, arthritis, other inflammatory and autoimmune disorders, and cancer (Shahidi et al., 1998). Omega-3 was polyunsaturated fatty acids (PUFAs) contains long chain carbon double bound. Concentrate omega-3 was done by selective hydrolysis in sn-1 and sn-3 glyceride to produce sn-2 glyceride greatly in omega-3 using enzyme lipase from Aspergillus niger yeast. According Bockisch (1993), in the majority of fish oil triglycerides, PUFAs were bound to the 2-position of the glyceride backbone. Enzymatic hydrolysis was produce acylglycerol from triacylglycerol using water as reactant and enzyme as catalyst. Some studies indicate that PUFA were most promptly absorbed from the intestines when FFA was given orally, were moderately absorbed as acylglycerols and were poorly absorbed as PUFA ethyl ester (Carvalho et al., 2009). Organic solvent hydrofobic could be used as medium in the hydrolysis reaction to increased activity and stability enzyme. Even if, it increased substrat selectivity. Solvent hydrophobic heptane almost used as media to increased activity and stability due to it hydrophobocity at the range 2<log p<4. This research aims to determined reaction factor condition that could produce maximum degree of hydrolysis of fish oil in media without or with added-heptane media. Besides, it determined the correlation between maximum degree of hydrolysis of fish oil and sum amount of omega-3 fatty acid. The step of this research are characterize fish oil, calculate Activity enzyme (unit), and determine correlation between reaction parameter such as temperature, pH, and water addition as basis optimum condition for hydrolysis enzymatic in added-heptane media. Temperature, pH and water content used in this research are 25oC-65oC, 5-9, and 1%-5% respectively. Degree of hydrolysis showed catalytic activity enzyme to the ester bound triacylglycerol. Procedure of this research started with do enzymatic hydrolysis fish oil and do hydrolysis fish oil on the medium heptane. Analysis include acid value, saponification value, and GC MS measurement. Fish oil in this research had acid value and saponification value as much 3,26 and 204,81 respectively. Fish oil contain 34,98% unsaturated fatty acid include omega-3 as big as 1,81%,22,76% saturated fatty acid, alkana (11,19%), aldehid (0,88%), squalene (4,8%) and lanosterol (24,96%). Unit activity from the spectrophotometry measurement was 7939 U/g. Optimum condition according to the enzymatic hydrolysis were pH 5 and 45oC. The degree of this condition was 28,07%. According to the enzymatic hydrolysis in added heptane media, water addition optimum is 1% with the 26,16% degree hydrolysis. By using this optimum condition (pH 5, temperature 45oC, and water addition 1%), enzymatic hydrolysis in organic solvent were done. Heptane used as organic solvent media. According to this 5 research, in every point of temperature, the degree of hydrolysis increased except at 65oC due to denaturation of protein enzyme at 65oC. Temperature optimum for hydrolysis enzymatic in the organic solvent heptane was 25oC. According to
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Judul: Closed Knight’s Tour pada Papan Catur Berbentuk Persegi Panjang dengan Ukuran Maksimal 8 × 8
Abstrak: Closed Knight’s Tour merupakan langkah kuda yang mengunjungi setiap kotak pada papan catur tepat satu kali dengan langkah kuda berawal dan berakhir pada kotak yang sama. Graf yang terbentuk dari closed knight’s tour dinotasikan sebagai graf G(m,n), dengan m adalah banyaknya baris dan n adalah banyaknya kolom. Graf tersebut memuat Hamiltonian cycle. Sebuah graf terhubung G adalah graf bipartite jika dan hanya jika graf tersebut tidak memiliki cycle dengan panjang ganjil. Papan catur yang memenuhi syarat cukup untuk memiliki closed knight’s tour adalah papan catur berukuran 5 × 6, 5 × 8, 6 × 6, 6 × 7, 6 × 8, 7 × 8, dan 8 × 8.
Keyword: bipartite, closed knight’s tour, hamiltonian cycle, knight’s tour, teori graf