Jurnal Penelitian Pendidikan IPA (JPPIPA)
Vol 12 No 5 (2026): In Progress

Potential Antagonistic Interactions of Cassia alata L. Leaf Extract and Commercial Antibiotics against Staphylococcus aureus: An In Vitro Evaluation

Oki Rokhim Mawakhid (Universitas Bengkulu)
Putri Ramanda (Universitas Bengkulu)
Samuel Billie Tua Sinaga (Universitas Bengkulu)
Winda Shari (Universitas Bengkulu)
Avidlyandi Avidlyandi (Universitas Bengkulu)
Khafit Wiradimafan (Universitas Bengkulu)
Salprima Yudha S. (Universitas Bengkulu)
Risky Hadi Wibowo (Universitas Bengkulu)
Morina Adfa (Universitas Bengkulu)



Article Info

Publish Date
25 May 2026

Abstract

Several in vitro studies have demonstrated that the combination of plant extracts with antibiotics may reduce the minimum inhibitory concentration (MIC) of antibiotics against resistant microorganisms. Interactions between plant extracts and antibiotics can be synergistic, additive, or antagonistic. This study aimed to evaluate the potential interaction between Cassia alata leaves methanol extract and five selected conventional antibiotics in inhibiting the growth of Staphylococcus aureus ATCC 29213. Antibacterial activity was assessed using the well diffusion and paper strip methods. The methanol extract of C. alata leaves, when tested singly at a concentration of 100 mg/mL, produced an average inhibition zone of 11.74 mm. Four antibiotics, namely ciprofloxacin, clindamycin, chloramphenicol, and tetracycline, exhibited stronger antibacterial activity with inhibition zones ranging from 19.56–27.26 mm, whereas co-trimoxazole showed no inhibitory effect. The combination of C. alata leaves methanol extract with ciprofloxacin, clindamycin, chloramphenicol, tetracycline, and cotrimoxazole resulted in inhibition zones of 22.26 ± 0.703 mm, 22.54 ± 1.222 mm, 17.91 ± 1.094 mm, 17.57 ± 0.652 mm, and 9.30 ± 1.180 mm, respectively. The combined treatments have potential antagonistic effects, as the inhibition zones were smaller than the sum of the individual activities of the extract and antibiotics. Therefore, the combination was considered less effective in suppressing growth of S. aureus ATCC 29213

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Journal Info

Abbrev

jppipa

Publisher

Subject

Agriculture, Biological Sciences & Forestry Biochemistry, Genetics & Molecular Biology Chemical Engineering, Chemistry & Bioengineering Chemistry Education Materials Science & Nanotechnology Physics

Description

Science Educational Research Journal is international open access, published by Science Master Program of Science Education Graduate Program University of Mataram, contains scientific articles both in the form of research results and literature review that includes science, technology and teaching ...