Judul: Antidiabetic Activity In Vitro and Organoleptic Test from Combination Black Tea, Turmeric, and Ginger Extract
Abstrak: Teh hitam (Camellia sinensis L), kunyit (Curcuma longa L.), dan jahe (Zingiber officinale) merupakan tanaman yang berpotensi menjaga kadar gula darah pada penderita diabetes melitus. Namun, dasar ilmiah mengenai kombinasi teh hitam, kunyit, dan jahe dalam inhibisi enzim α-glukosidase masih terbatas. Oleh karena itu, penelitian ini bertujuan menentukan kombinasi ekstrak teh hitam, kunyit, dan jahe yang paling optimum terhadap inhibisi α-glukosidase serta uji organoleptik pada kombinasi aktivitas inhibisi α-glukosidase paling optimum. Metode penelitian meliputi analisis fitokimia, aktivitas inhibisi α-glukosidase, dan uji organoleptik. Ekstrak etanol kunyit sebagai ekstrak terbaik dengan nilai IC50 sebesar 9,48±0,05 μg/mL. Aktivitas inhibisi α-glukosidase tertinggi pada kombinasi F7 yang terdiri dari ekstrak teh hitam, kunyit, dan jahe sebesar 67,86±0,93 %. Uji organoleptik kombinasi F7 menunjukkan tingkat kesukaan tertinggi oleh P3 dan P2 pada warna, aroma, konsistensi, dan aftertaste, sedangkan rasa pada P3. Simpulan penelitian ini adanya kemampuan kombinasi ekstrak teh hitam, kunyit, dan jahe dalam inhibisi enzim α-glukosidase yang menunjukkan interkasi sinergis., Black tea (Camellia sinensis L), turmeric (Curcuma longa L.), and ginger (Zingiber officinale) are plants that have the potential to maintain blood sugar levels in diabetes mellitus sufferers. However, the scientific basis regarding the combination of black tea, turmeric, and ginger in α-glucosidase inhibition is still limited. Therefore, this study aims to determine the optimum combination of black tea extract, turmeric, and ginger for inhibition of the α-glucosidase and an organoleptic test on the optimum combination of α-glucosidase inhibition activity. The method of the research included phytochemical analysis, inhibitory activity of the α-glucosidase, and organoleptic tests. Turmeric ethanol extract was the best extract with an IC50 value of 9.48±0,05 μg/mL. The highest inhibitory activity of α-glucosidase in combination F7 consisting of black tea extract, turmeric, and ginger was 67.86±0.93 %. The organoleptic test of the combination F7 showed the highest level of preference by the P3 and P2 on the of color, aroma, consistency, and aftertaste, while the taste was in the P3. The conclusion of this study is the ability of the combination of black tea extract, turmeric, and ginger to inhibit the enzyme α-glucosidase which shows a synergistic interaction.
Keyword: black tea, ginger, α-glucosidase, organoleptic, turmeric

Judul: Pengaruh Suhu dan Lama Penyeduhan Teh Hitam (Camellia sinensis) serta Proses Pencernaan secara In Vitro terhadap Penghambatan Aktivitas Enzim Alfa Amilase dan Alfa Glukosidase secara In Vitro
Abstrak: Diabetes is a chronic disease that occurs either when the pancreas does not produce enough insulin or when the body cannot effectively use the insulin. Natural alpha amylase and alpha glucosidase inhibitors from food-grade plants offer an attractive strategy to eather manage or prevent type 2 diabetes by controlling of starch breakdown and intestinal glucose absorption. Black tea is the second most widely consumed beverage in the world after water. A lot of researches about bioactive compounds in tea related have been done. In this study, six extracts treated with different combination of temperature and brewing time were investigated for alpha amylase and alpha glucosidase inhibitory potential. Furthermore, the influence of the digestion condition in vitro to the activity of the enzymes was also performed in this study. The enzymes inhibitory and total phenol was measured by spectrophotometric while tannin content was measured by gravimetric method. Results showed that tea brewed by 70oC 15 minutes, 70oC 30 minutes, 100oC 5 minutes, 100oC 15 minutes can optimally inhibit amylase at initial extract (as an estimation of salivary alpha amylase), 70oC 15 minutes and 100oC 5 minutes can optimally inhibit pH digestion-controlled extract (pancreatic amylase), 70oC 30 minutes and 100oC 30 minutes can optimally inhibit alpha glucosidase at initial extract, also 70oC 15 minutes, 100oC 15 minutes, and 100oC 30 minutes can optimally inhibit at pH digestion-controlled extract. Alpha amylase inhibitory has a positive correlation with tannin content but not with total phenol. While alpha glucosidase inhibitory showed no correlation with tannin and showed a negative correlation with total phenol.
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Judul: Struktur Populasi, Pertumbuhan, dan Reproduksi Lobster Air Tawar, Cherax quadricarinatus di Danau Maninjau
Abstrak: One of the non native species in Lake Maninjau, redclaw crayfish (Cherax quadricarinatus) was studied. This population was sampled biweekly between May and September in six sampling sites (Bayur, Sungai Batang, Batu Nanggai, Sigiran, Sungai Tampang, and Utara). This research was aimed to study the population structure, growth, and reproduction of the redclaw crayfish. As a non native species, the redclaw crayfish had distributed in all sampling sites in varied density and sex ratio 1:1. Growth pattern of male was positive allometric and female was isometric. The moult increment (MI) of male and female was 2.7 mm and 3.59±0.90 mm, respectively. The percentage of premoult carapace length (PCMI) of male and female was 5.1% and 7.9±1.95%, respectively. Growth function of the red claw crayfish was CLt=82 􀵤1-e􁉀-1.2(t+0.09)􁉁􀵨. Based on the temporal pattern of gonadal development, Cherax quadricarinatus spawned along May and September with a peak was on August. Average of ovarian and pleopodal fecundity was relatively high which were 626±255 and 383±173, respectively. The ovarian fecundity was related with total wet body weight and pleopodal fecundity was related with endopod width
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