Judul: Chemical and Microbiological Characteristics of Fermented Spirulina Symbiotic Jelly Drink
Abstrak: Simbiotik merupakan kombinasi sinergis antara probiotik dan prebiotik, salah satunya dalam menimalisir prevalensi konstipasi. Simbiotik tersebut dapat diaplikasikan pada minuman jeli. Penelitian ini bertujuan menentukan karakteristik simbiotik Spirulina sebelum dan sesudah fermentasi, menentukan pengaruh penambahan Spirulina 0%, 5%, 7,5%, dan 10% terhadap karakteristik minuman jeli simbiotik, dan menentukan perlakuan terpilih minuman jeli simbiotik. Penelitian meliputi produksi Spirulina, kultur starter bakteri, fermentasi Spirulina, dan pembuatan minuman jeli simbiotik Spirulina fermentasi. Hasil penelitian menunjukkan bahwa fermentasi Spirulina selama 48 jam meningkatkan jumlah total Bakteri Asam Laktat (BAL) (2,7 log CFU/ml), dan Total Asam Tertitrasi (TAT) (2,32%), serta menurunkan nilai pH 3,94. Spirulina fermentasi pada minuman jeli berpengaruh nyata terhadap nilai viskositas, nilai pH, TAT, total BAL, total mikroba, serat pangan, dan aktivitas antioksidan. Perlakuan terpilih pada penambahan Spirulina fermentasi 10% dengan karakteristik viskositas 142,8 cp, nilai pH 4,06, TAT 0,22%, total BAL 7,91 log CFU/ml, total mikroba 8,02 log CFU/ml, aktivitas antioksidan 100,11 μmolTE/g, dan %Angka Kecukupan Gizi (AKG) serat pangan 11,37% dengan peningkatan 119,9%., Symbiotics are a synergistic combination of probiotics and prebiotics. One of which is to minimize the prevalence of constipation. The symbiotic can be applied to jelly drinks. This study aimed to characterize the symbiotic of fermented Spirulina before and after fermentation, to determine the effect of adding fermented Spirulina 0%, 5%, 7,5%, and 10% to the characteristics of symbiotic jelly drinks, and to determine the selected treatment for symbiotic jelly drinks. The research included Spirulina production, bacterial starter culture, Spirulina fermentation, and making Spirulina fermented symbiotic jelly drink. The results showed that fermentation of Spirulina for 48 hours increased the lactic acid bacteria (LAB) (2,7 logs CFU/ml), total acid titrated (TAT) (2,32%), and decreased the pH value of 3,94. Fermented Spirulina in jelly drinks significantly affected the values of viscosity, pH, TAT, total LAB, total microbial, dietary fiber, and antioxidant activity. The selected treatment was the addition of 10% fermented Spirulina with a viscosity of 142,8 cp, pH value of 4,06, TAT 0,22%, total LAB 7,91 log CFU/ml, total microbes 8,02 log CFU/ml, the antioxidant activity of 100,11 μmolTE/g, and %Nutritional Adequacy Rate dietary fiber of 11,37% with an increase of 119,9%.
Keyword: fermentation, Lactobacillus plantarum SK(5), Spirulina

Judul: Chemical Characterization of Fermented Spirulina and Screening of Metabolic Compounds Produced by it
Abstrak: Spirulina platensis dapat menstimulasi pertumbuhan mikroba non patogenik. Penelitian sebelumnya menunjukkan Spirulina fermentasi memiliki karakteristik kimiawi dan aktivitas antioksidan. Pengeringan beku (liofilisasi) dilakukan dan digunakan dalam penelitian ini. Penelitian bertujuan menentukan karakteristik kimiawi dan penapisan senyawa metabolit dari Spirulina fermentasi setelah liofilisasi. Spirulina fermentasi liofilisasi memiliki nilai pH 4,15 ± 0,00, total asam tertitrasi (TAT) 11,96 ± 0,00 %, dan total bakteri asam laktat (BAL) <2,5 × 101 ± 0,00. Spirulina fermentasi mengandung komponen aktif flavonoid, steroid, tanin, saponin dan fenol hidrokuinon, serta negatif alkaloid. Penapisan senyawa metabolit menggunakan LC-MS/MS menghasilkan 88 senyawa, terdiri dari golongan terpen atau terpenoid, fenolik, dan alkaloid, serta kelompok asam amino, asam lemak, asam organik, natural pigmen, gula dan kelompok lainnya. Senyawa dominan teridentifikasi diantaranya propenyl pyrazine, ribonic acid, pyroglutamic acid, phenyllactic acid, 1,2-cyclohexanedicarboxylic acid, didecyl ester, cis-caftaric acid, malic acid, 1,2-cyclohexanedicarboxylic acid, cyclohexylmethylnonyl ester, dan gallic acid., Spirulina platensis can stimulate the growth of non-pathogenic microbes. Previous studies have shown that lyophilized fermented Spirulina and Spirulina biomass have antioxidant activity. The study aims to determine the chemical characteristics and screening of metabolites produced by lyophilized fermented Spirulina and Spirulina biomass. Lyophilized fermented Spirulina had a pH value of 4,15 ± 0,00, total titrated acid (TAT) 11,96 ± 0,00%, and total lactic acid bacteria (LAB) < 2,5 × 101 ± 0,00. Fermented Spirulina contains active components of flavonoids, steroids, tannins, saponins and phenol hydroquinone, as well as negative alkaloids. Screening of metabolites using LC-MS/MS resulted in 88 compounds, consisting of terpenes or terpenoids, phenolics, and alkaloids, as well as groups of amino acids, fatty acids, organic acids, natural pigments, sugars and other groups. The dominant compounds identified were propenyl pyrazine, ribonic acid, pyroglutamic acid, phenyllactic acid, 1,2- cyclohexanedicarboxylic acid, didecyl ester, cis-caftaric acid, malic acid, 1,2- cyclohexanedicarboxylic acid, cyclohexylmethylnonyl ester, and gallic acid.
Keyword: Lactobacillus plantarum SK (5), Spirulina, metabolomic, metabolites

Judul: Truncated Stop Loss as a Optimal Solution of Reinsurance Agreement in One-Period Model
Abstrak: Reinsurance is one of risk management efforts of an insurance company, which is called the cedent. Similar with insurance, reinsurance constitutes the cedent to pay the premium. We consider one-period reinsurance model and derive a rule which minimizes the ruin probability of the cedent for a fixed reinsurance premium. Therefore, it is needed to construct an optimal reinsurance agreement for the cedent. The premium is calculated according to four different principles, i.e. economic, generalized zero-utility, Esscher, and mean-variance principles. Stop loss is a reinsurance contract which protect the insurance company for losses that exceed a certain amount. The result of this research shows that a truncated stop loss is an optimal agreement in the class of all reinsurance contracts with various premiums calculated using above mentioned principles.
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