Judul: Dual Enzymatic Production of Bioactive Peptides from Velvet Bean Protein Concentrate
Abstrak: Bioactive peptides have a great potential for application for functional foods. Velvet bean (Mucuna pruriens) is a promising source of parent protein for the production of bioactive peptides due to its high protein and hydrophobic amino acid composition. This research aimed to obtain the optimum operating conditions for the continuous production of bioactive peptides from velvet bean protein concentrate using dual enzymatic proteolysis. This research was divided into two main stages: preparation of velvet bean protein concentrate and continuous production of bioactive peptides with emphasis on the influence of the enzyme-to- substrate ratio, pH, and residence time. Due to its high enzyme rejection, a 5-kDa PES membrane was used. The optimum operating conditions obtained were: [E]/[S] = 5%, pH = 7.5, and residence time = 12 h. With these operating conditions, the antioxidant capacities and ACE inhibition of the permeate were 0.1803 mg AEAC/mL (DPPH method), 0.1589 mg AEAC/mL (FRAP method), and 74.29%, respectively. Compared to the substrate, there was a decrease in antioxidant capacity and almost a twofold increase in ACE inhibition. The decrease in the antioxidant capacity was due to phenolic compound rejection by the membrane. Moreover, a long-term continuous production of velvet bean protein concentrate was performed. An increase in antioxidant capacity, ACE inhibition, and TMP was observed during the 72-h filtration. A combination of physical and chemical membrane cleaning was able to recover the flux up to 85.6%.
Keyword: ACE inhibition, antioxidant, bioactive peptides, enzymatic membrane reactor, velvet bean

Judul: Preparasi Peptida Bioaktif dari Konsentrat Tempe Koro Benguk Menggunakan Reaktor Membran Enzimatis
Abstrak: Kacang koro benguk memiliki potensi sebagai sumber peptida bioaktif. Fungsionalitas peptida bioaktif dapat ditingkatkan dengan proses fermentasi dan hidrolisis menggunakan enzim alkalase secara kontinu. Terdapat beberapa parameter yang berpengaruh dalam hidrolisis protein koro benguk secara kontinu dengan reaktor membran enzimatis yaitu rasio konsentrasi enzim terhadap konsentrasi substrat (E/S) dan residence tim. Penelitian ini bertujuan memproduksi peptida bioaktif tempe koro benguk secara kontinu dengan menggunakan reaktor membran enzimatis dan mempelajari parameter terhadap produksi peptida bioaktif. Penelitian dilakukan dalam beberapa tahap: proses pembuatan tempe koro benguk, isolasi dan karakterisasi protein tempe koro, filtrasi enzim alkalase, serta produksi kontinu peptida bioaktif dengan faktor E/S dan residence time.Karakteristik fungsional yang diamati antara lain kapasistas antioksidan, penghambatan angiotensin converting enzyme (ACE), total fenol, dan kadar protein. PES membran dengan MWCO 5 kDa digunakan dalam tahapan produksi kontinu peptida bioaktif berdasarkan rejeksi enzim dan profil tekanan transmembran pada filtrasi enzim alkalase. Permeat dengan perlakuan E/S 10% dan residene time=9 jam memiliki karakteristik fungsional terbaik. Selanjutnya, hidrolisat yang didapatkan dari kondisi optimum dipisahkan menggunakan PES membran dengan berbagai nilai MWCO (2 dan 4 kDa). Membran dengan 2 kDa menghasilkan permeat dengan profil fungsionalitas yang tinggi. Nilai IC50 antioksidan (metode DPPH) dari permeat hasil terbaik yaitu 7,56 ± 0.30 μg/mL, IC50 antioksidan (metode FRAP) yaitu 12,51 ± 0.40 μg/mL, dan IC50 penghambatan ACE yaitu 0,60 μg/mL. Penelitian ini menunjukkan bahwa produksi peptida yang memiliki aktivitas penghambatan ACE dan antioksidan dapat dilakukan dengan mengadopsi kombinasi metode fermentasi dan in vitro proteolisis secara kontinu dalam reaktor membran enzimatis., Velvet bean has potential as a source of bioactive peptides. The functionality of bioactive peptides can be improved by fermentation and continuous hydrolysis using alcalase enzyme. There are several parameters that influence continuous hydrolysis of velvet bean protein using enzymatic membrane reactor, namely the ratio of enzyme concentration to substrate concentration (E/S) and residence time. This study aims to produce bioactive peptides of velvet bean tempeh continuously using enzymatic membrane reactor and study the parameters for the production of bioactive peptides. This research was conducted by producing velvet bean tempeh, isolation and analysis of velvet bean tempeh protein, filtration of alcalase enzyme, and continuous production of bioactive peptides with factors E/S and residence time. Functional characteristics observed were antioxidant capacity, angiotensin converting enzyme (ACE) inhibition,total phenolic compound, and protein. PES membrane with MWCO 5 kDa was used in the continuous production of bioactive peptides based on enzyme rejection and transmembrane pressure profiles on alcalase enzyme filtration. Permeate produced with E/S= 10% and residence time= 9 hours had the best functional characteristics. Furthermore, the hydrolysate obtained from the optimum conditions was separated using PES membrane with various MWCO values (2 and 4 kDa). The 2 kDa membrane produces a permeate with a high functionality profile. The antioxidant IC50 value (DPPH method) was 7.56 ± 0.30 μg/mL, antioxidant (FRAP method) IC50 was 12.51 ± 0.40 μg/mL, and the ACE inhibition IC50 was 0.60 μg/mL. This study shows that the production of peptides that have ACE inhibitory and antioxidant activity can be carried out by adopting a combination of continuous fermentation and in vitro proteolysis methods in
Keyword: Alcalase, bioactive peptide, enzymatic membrane reactor, tempeh, velvet bean tempeh

Judul: Karakteristik fisik siklon tropis di samudera hindia bagian selatan dan pengaruhnya terhadap curah hujan di Jawa, Bali dan Nusa Tenggara
Abstrak: Secara meteorologis, siklon tropis adalah sebuah tekanan rendah yang terbentuk secara umum di daerah tropis yang memiliki lintang rendah antara 10 derajat dan 20 derajat LU/LS dari ekuator. Siklon tropis merupakan bagian penting dari sistem sirkulasi atmosfer yang berperan dalam perpindahan panas dari daerah katulistiwa menuju daerah lintang lebih tinggi. Penelitian ini bertujuan untuk menganalisis karakteristik fisik siklon tropis di Samudera Hindia bagian selatan dan pengaruh siklon tersebut terhadap curah hujan di Jawa, Bali dan Nusa Tenggara.
Keyword: