Uji efektivitas ekstrak kulit jengkol (Pithecellobium lobatum benth.) terhadap pertumbuhan Streptococcus viridans: studi eksperimental laboratoris

Abstract

Pendahuluan: Kulit jengkol (Pithecellobium lobatum Benth.) merupakan limbah organik yang melimpah di pasar tradisional namun belum dimanfaatkan secara optimal. Kulit jengkol mengandung senyawa aktif seperti alkaloid, flavonoid, glikosida, steroid antrakinon, tanin, saponin, dan asam fenolat yang diketahui memiliki potensi antibakteri. Senyawa-senyawa ini dapat menghambat pertumbuhan bakteri dengan merusak struktur peptidoglikan pada dinding sel sehingga integritas sel terganggu. Penelitian ini bertujuan untuk menganalisis aktivitas antibakteri ekstrak kulit jengkol terhadap Streptococcus viridans secara in vitro. Metode: Penelitian eksperimental ini menggunakan rancangan post-test only control group design. Ekstraksi kulit jengkol dilakukan dengan metode maserasi, kemudian dilarutkan dalam DMSO menjadi lima konsentrasi (5%, 10%, 20%, 40%, 80%). Chlorhexidine gluconate 0,2% digunakan sebagai kontrol positif, sedangkan DMSO sebagai kontrol negatif. Uji antibakteri dilakukan dengan metode difusi cakram Kirby-Bauer pada media MHA dengan empat kali pengulangan. Analisis data dilakukan menggunakan SPSS versi 29 dengan uji normalitas Shapiro-Wilk, homogenitas Levene test, dilanjutkan ANOVA dan Post Hoc LSD. Hasil: Rata-rata diameter zona hambat meningkat seiring konsentrasi: 5% (7,325 mm), 10% (9,550 mm), 20% (10,400 mm), 40% (11,800 mm), dan 80% (14,775 mm). Terdapat perbedaan signifikan antar kelompok (p=0,001), kecuali antara konsentrasi 10%-20%, 20%-40%, dan 80% dengan kontrol positif (p>0,05). Simpulan: Ekstrak kulit jengkol efektif menghambat pertumbuhan Streptococcus viridans secara in vitro.



Effectiveness test of jengkol peel extract (Pithecellobium lobatum benth.) against Streptococcus viridans growth: a laboratory experimental study



Introduction: Jengkol peel (Pithecellobium lobatum Benth.) is an abundant organic waste often discarded in traditional markets but remains underutilized. It contains active compounds such as alkaloids, flavonoids, glycosides, steroids, anthraquinones, tannins, saponins, and phenolic acids, many of which exhibit antibacterial potential. These compounds can inhibit bacterial growth by disrupting the peptidoglycan structure in the bacterial cell wall, thereby compromising cell integrity. This study aimed to analyze the antibacterial effectiveness of jengkol peel extract against Streptococcus viridans in vitro. Methods: This laboratory experimental study used a post-test-only control group design. Jengkol peel was extracted using the maceration method and dissolved in DMSO to obtain five concentrations (5%, 10%, 20%, 40%, and 80%). Chlorhexidine gluconate (0.2%) served as a positive control, and DMSO as a negative control. The antibacterial activity was evaluated using the Kirby-Bauer disc diffusion method on Mueller-Hinton agar (MHA), with four replicates per treatment. Data were analyzed using SPSS version 29 with Shapiro-Wilk test for normality, Levene’s test for homogeneity, followed by one-way ANOVA and post hoc LSD tests. Results: The mean inhibition zone diameters increased with higher concentrations: 5% (7.325 mm), 10% (9.550 mm), 20% (10.400 mm), 40% (11.800 mm), and 80% (14.775 mm). Significant differences were observed among treatment groups (p=0.001), except between 10%-20%, 20%-40%, or 80% and the positive control (p>0.05). Conclusion: Jengkol peel extract demonstrates antibacterial activity against Streptococcus viridans in vitro.