Electronic Theses and Dissertation

Jengkol (Pithecellobium jiringa) merupakan tumbuhan yang hidup di Asia Tenggara
termasuk Indonesia. Biji jengkol dimanfaatkan sebagai bahan makanan, sedangkan kulitnya hanya
sebagai limbah. Masyarakat Indonesia telah lama memanfaatkan daun dan kulit buah jengkol
sebagai obat tradisional. Kandungan senyawa alami dalam kulit jengkol yaitu alkaloid, flavonoid,
saponin, steroid, tanin dan terpenoid yang memiliki efek farmakologis. Penelitian ini bertujuan
untuk mengetahui ekstrak n-heksan kulit buah jengkol (P. jiringa) memiliki efek antibakteri
terhadap pertumbuhan S. aureus. Penelitian ini merupakan observasi dan eksperimental
laboratorium (Experimental Research Laboratory) dengan metode difusi lempeng agar (KirbyBauer). Ekstrak kulit buah jengkol dibuat menggunakan metode ekstraksi maserasi menggunakan
pelarut n-heksan. Perlakuan terdiri dari konsentrasi ekstrak n-heksan kulit buah jengkol yaitu 15%,
30%, 45%, 60%, dan 75%, vancomycin sebagai kontrol positif dan CMC 1% sebagai kontrol
negatif. Daya hambat diperoleh berdasarkan pengukuran zona hambat yang terbentuk di sekitar
disk menggunakan jangka sorong. Hasil penelitian didapatkan rata-rata ukuran zona hambat
konsentrasi 15%, 30%, 45%, 60%,dan 75% yaitu 6,50 mm, 6,30 mm, 6,70, 6,61mm, dan 6,65mm.
Berdasarkan penelitian dapat disimpulkan ekstrak n-heksan kulit buah jengkol memiliki efek
antibakteri yang lemah terhadap pertumbuhan bakteri S. aureus.

Jengkol (Pithecellobium jiringa) is a plant that grows in Southeast Asia, including Indonesia. Jengkol seeds are used as a food ingredient, while the skin is often considered as waste. Traditional medicine in Indonesian communities has long utilized jengkol leaves and fruit skin for their medicinal properties. The natural compounds found in jengkol fruit skin include alkaloids, flavonoids, saponins, steroids, tannins, and terpenoids, which have pharmacological effects. This research aims to investigate the antibacterial effect of n-hexan extract from jengkol fruit skin (P. jiringa) on the growth of S. aureus. The study follows an observational and experimental laboratory design, using the agar plate diffusion method (Kirby-Bauer method). The jengkol fruit skin extract is prepared using the maceration extraction method with n-hexan as the solvent. The treatments include different concentrations of the n-hexan extract: 15%, 30%, 45%, 60%, and 75%. Vancomycin is used as the positive control, and 1% CMC serves as the negative control. The inhibitory activity is determined by measuring the diameter of the inhibition zone around the disks using a caliper. The results show that the average size of the inhibition zones for the concentrations of 15%, 30%, 45%, 60%, and 75% are 6.50 mm, 6.30 mm, 6.70 mm, 6.61 mm, and 6.65 mm, respectively. Based on research, it can be concluded that n-hexan extract of jengkol fruit skin has a weak antibacterial effect on the growth of S. aureus.