Judul: Phytochemical Analysis, Antioxidant Activity, and Collagenase Inhibition of Red Betel Leaf Extract (Piper crocatum Ruiz & Pav.) In Vitro.
Abstrak: Sirih merah (Piper crocatum Ruiz & Pav.) merupakan tanaman dengan berbagai kandungan senyawa aktif. Penelitian ini bertujuan menentukan komponen fitokimia, aktivitas antioksidan, dan inhibisi kolagenase ekstrak etil asetat dan air daun sirih merah. Pengukuran kadar air dilakukan dengan metode pengeringan. Ekstraksi dilakukan dengan metode maserasi untuk pelarut etil asetat dan metode perebusan untuk pelarut air. Metode LC-MS digunakan dalam identifikasi senyawa aktif. Metode DPPH digunakan dalam uji antioksidan. Uji inhibisi kolagenase dilakukan dengan 1,10-Fenantrolin sebagai kontrol positif. Kadar air diperoleh sebesar 8.12 ± 0.63%. Nilai rendemen ekstrak etil asetat dan air berturut-turut sebesar 7.71 ± 0.35% dan 27.88 ± 0.59%. Senyawa dugaan dengan kelimpahan relatif terbesar pada kedua ekstrak yaitu Schisandrin B dan 2-(4-Allyl-2,6-dimethoxyphenoxy)-1-(3,4,5-trimethoxyphenyl)-1-propanol. Nilai IC50 penghambatan DPPH pada ekstrak air sebesar 1098.99 ppm dan ekstrak etil asetat sebesar 1378.59 ppm. Persen inhibisi kolagenase ekstrak etil asetat dan air tidak berbeda nyata, yaitu berturut-turut sebesar 89.9% dan 89.09%., Red betel (Piper crocatum Ruiz & Pav.) is a plant with various active compounds. This study aimed to determine the phytochemical components, antioxidant activity, and inhibition of the collagenase extract of ethyl acetate and red coat leaf water. Measurement of moisture content is carried out by the drying method. Extraction is carried out by the maceration method for ethyl acetate solvents and boiling methods for water solvents. The LC-MS method is used in the identification of active compounds. The DPPH method is used in the antioxidant test. The collagenase inhibition test was performed with 1,10-Phenantrolin as a positive control. The moisture content obtained is 8.12 ± 0.63%. The yield values of ethyl acetate and water extracts were 7.71 ± 0.35% and 27.88 ± 0.59%, respectively. The suspected compounds with the greatest relative abundance in both extracts are Schisandrin B and 2-(4-Allyl-2,6-dimethoxyphenoxy)-1-(3,4,5-trimethoxyphenyl)-1-propanol. The IC50 value of DPPH inhibition in aqueous extract is 1098.99 ppm and in ethyl acetate extract is 1378.59 ppm. The percentage of collagenase inhibition for ethyl acetate and water extracts is not significantly different, which is 89.9% and 89.09% respectively.
Keyword: antioxidant, collagenase, DPPH, LC-MS, red betel

Judul: Total Phenolics, Flavonoids, and ɑ-Glucosidase Inhibitory Activity of n-Hexane, Ethyl Acetate and Methanol Extracts of Red Betel (Piper crocatum)
Abstrak: Sirih merah (Piper crocatum) mempunyai berbagai senyawa dengan kemampuan penghambatan enzim ɑ-glukosidase. Penelitian ini bertujuan menentukan ekstrak yang memiliki tingkat kandungan fenolik dan flavonoid yang optimal, serta penghambatan tertinggi pada enzim α-glukosidase. Metode maserasi bertingkat digunakan untuk mengekstraksi senyawa bioaktif sirih merah menggunakan pelarut-pelarut dengan peningkatan kepolaran (n-heksana, etil asetat, metanol). Pengujian dilakukan terhadap kadar fenolik total, flavonoid, serta kemampuan inhibisi ɑ-glukosidase. Hasil pengukuran total kadar fenolik, flavonoid, dan aktivitas penghambatan α-glukosidase menunjukkan nilai yang secara signifikan berbeda (p<0,05) pada semua ekstrak dengan total kadar fenolik dan flavonoid tertinggi pada ekstrak n-heksana berturut-turut sebesar 25,68 ± 0,29 mg GAE/g dan 65,84 ± 0,96 mg QE/g. Sementara itu, ekstrak metanol daun sirih merah memiliki daya hambat diantara semua ekstrak dengan nilai persen inhibisi α-glukosidase sebesar 43,87 ± 1,83%., Red betel leaf (Piper crocatum) had various compounds with the ability to inhibit α-glucosidase enzymes. The research aimed to determine the extract with optimal levels of phenolic and flavonoid content, as well as the highest inhibition of α-glucosidase enzyme. A multistage maceration method was used to extract bioactive compounds from red betel leaf using solvents with increasing polarity (n-hexane, ethyl acetate, methanol). Tests were conducted on the total phenolic content, flavonoids, and α-glucosidase inhibition ability. The measurement results of the total phenolic content, flavonoids, and α-glucosidase inhibition activity showed significantly different values (p<0,05) in all extracts with the highest total phenolic and flavonoid content in n-hexane extract, respectively, at 25,68 ± 0,29 mg GAE/g and 65,84 ± 0,96 mg QE/g. Meanwhile, the methanol extract of red betel leaf had inhibitory power among all extracts with a percentage inhibition of α-glucosidase at 43,87 ± 1,83%.
Keyword: ɑ-glukosidase/ɑ-glucosidase, antidiabetes/antidiabetic, fenolik/phenolic, flavonoid/flavonoid, sirih merah/red betel

Judul: Dinamika Sistem Ekonomi dengan Model Overlapping-Generation
Abstrak: This manuscript describes a modern macroeconomic model in discrete time so-called Overlapping-Generation Model. In general, modeling framework of Overlapping-Generation is assumed that each person lives for only two periods, i.e. he/she works in the first period and retires in the second. By maximizing lifetime utility, which depends on consumption in the two periods of life, there will exist a steady state condition. Steady state happens when capital per capita at the first and the second periods are equal. In the end, economics converges to a steady state. Some numerical simulations show the effects of some parameters to the steady state condition.
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