Isolation of Endophytic Fungi QPS 05 From Quercus Phillyraeoides A. Gray and Its Potential for α-Glucosidase Inhibitory Activity

Endophytic fungi are the microorganisms that spend all or part of their life cycles within plant tissue without causing harmful effects on the plant. In this study, 14 endophytic fungus from Quercus phillyraeoides A. Gray were isolated. Alternaria sp. QPS 05, an endophytic fungi which was isolated from the stem of Q. phillyraeoides A. Gray showed the highest α-glucosidase inhibitory activity. Further separation of ethyl acetate extract from the fungus led to the isolation of active substance from hexane-soluble fraction which give fatty acids mixture consist of palmitic acid, oleic acid, linoleic acid and linolenic acid (1) strong inhibitory activity against α-glucosidase. Isolated fatty acids (1) had inhibitory concentration (IC50) values against Saccharomyces cerevisiae was 12.10 μg/mL. The results of the present study showed that endophytic fungus from Alternaria sp. QPS 05 potentially contained a rich source of natural antidiabetic medicine

Efek Pengeringan pada Bagian Buah Labu Kuning (Cucurbita Moschata) terhadap Aktivitas Antioksidan, Sifat Kimia dan Struktur Morfologi

Labu kuning (C. moschata) merupakan salah satu tanaman yang banyak terdapat di Indonesia. Penelitian ini bertujuan untuk mempelajari aktivitas antioksidan, struktur morfologi, sifat kimia dan fisikokimia dari tiga komponen tepung yakni kulit, biji dan daging buah dari labu kuning. Ekstrak biji, kulit dan daging buah labu kuning diperoleh dengan maserasi menggunakan pelarut etanol. Dua metode pengeringan yang digunakan yakni pengeringan dengan sinar matahari dan oven pada suhu 50oC. Hasil uji aktivitas antioksidan dengan metode DPPH (2,2-diphenyl-1-picrylhydrazyl) menunjukkan bahwa biji labu kuning dengan metode pengeringan oven, memiliki aktivitas antioksidan yang paling tinggi, yakni memiliki aktivitas penangkapan radikal bebas sebesar 22,6% pada konsentrasi ekstrak 400 ppm, diikuti oleh kulit dan daging buah labu kuning masing-masing sebesar 16,7 dan 14,2%. Tepung kulit, biji dan daging buah labu kuning juga sudah dilakukan karakterisasi menggunakan SEM (Scanning Electron Microscopy) untuk mengetahui struktur morfologi permukaan, FTIR (Fourier Transform Infrared Spectroscopy) untuk mengetahui gugus fungsional senyawa dari labu kuning, XRD (X-ray diffraction) dan Uji Warna. Hasil analisis proksimat menunjukkan bahwa kandungan protein dan lemak dari biji labu kuning dengan metode pengeringan oven memiliki kandungan paling tinggi yakni sebesar 33,5% dan 33,3% sedangkan kandungan karbohidrat tertinggi dimiliki oleh daging buah labu kuning dengan pengeringan oven sebesar 75,3%. Hasil yang diperoleh menunjukkan bahwa perbedaan metode pengeringan menghasilkan karakteristik yang berbeda dari tepung labu kunin

In-vitro Antioxidant and Antibacterial Activities of Tegeran Wood (Cudrania JavanensisTrécul) Extracts [Aktivitas Antioksidan Dan Antibakteri Ekstrak Kayu Tegeran Secara In-vitro(Cudrania JavanensisTrécul)]

Cudrania javanensis generally used as natural dyes in Indonesia, but limitedis known about its biological activities. The study aimed to assess in vitro antioxidant and antibacterial activities of C. javanensis crude extracts. The antioxidant properties of crude extracts were determined by the DPPH free radical and ABTS method. Methanol and water extracts were also evaluated for their antimicrobial activities toward strain of Gram positivebacteria (Staphylococcus aureus) and Gram negative bacteria (Escherichia coli and Pseudomonas aeruginosa) by the agar well diffusion method. The results indicated that C. javanensis wood methanol extract exhibited good antioxidant activity than water extract, which against DPPH radical with IC50of 12.23±1.43 μg/mL, andscavenging to ABTS radical about 964.69±15.05 mg trolox equivalent/g at 0.025 mg/mL, respectively. However, both of extracts did not possess activity toward antibacterial assay. This study indicated that methanol and water extracts from C. javanensis wood could be used as natural antioxidant resources