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: Continuous Production of Bioactive Peptides from Mung Bean Concentrate using Alcalase Enzyme in an Enzymatic Membrane Reactor
Abstrak: Consuming foods containing antioxidants may help in reducing the risk of developing diseases. Peptides from mung beans have shown to exhibit antioxidative properties, thus may be a potential ingredient in the production of functional foods. Mung bean based bioactive peptides can be continuously produced through enzymatic hydrolysis using alcalase in an enzymatic membrane reactor. The research was divided into three stages namely isolation and characterisation of mung bean protein concentrate, continuous production of bioactive peptides with parameter variations (enzyme-substrate ratio, pH and residence time) and IC50 analysis performed on the permeate produced under optimum conditions. The permeate produced with the optimum conditions of 5% enzyme-substrate ratio, pH 7.5 and 10-hour residence time had the best antioxidant capacities of 28.2069 μg AEAC/mL (DPPH), 16.1442 μg AEAC/mL (FRAP), 91.6802% (ABTS). The < 2 kDa fraction had the best IC50 value of 0.2026 mg protein/mL.
Keyword: Alcalase, Antioxidant, Bioactive Peptide, Enzymatic Membrane Reactor, Mung Bean

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.
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