Metabolite Profile and Antibacterial Potential of Leaf And Stem Extract Castanopsis tungurrut (Blume) A.DC. against Escherichia coli and Staphylococcus aureus

Giving antibiotics or antibacterial drugs is one of the therapeutic strategies used to overcome the problem of infectious diseases caused by microorganisms. The emergence of bacteria that are resistant to various types of antibacterials can delay the recovery period from infectious disorders and cause treatment with antibiotics to become ineffective to use. For this reason, research to find new alternative antibacterial drugs from natural materials needs to be carried out. This study aims to determine the potential of Castanopsis tungurrut leaf and stem extracts as natural antibacterials against Escherichia coli and Staphylococcus aureus bacteria. The research method was extraction of samples by maceration with ethanol, ethyl acetate and aquadest. Antibacterial test with Kirby-Bauer method or disc diffusion. Identification of secondary metabolite compounds by TLC method and continued with metabolite profiling by spectrophotometric method. The results showed the highest antibacterial activity was found in 70 ethanol extract of stem at a concentration of 400 mg/mL with an inhibition zone diameter of 9.06 mm. The 70 ethanol leaf extract was detected to contain phenolics and flavonoids and the ethyl acetate leaf extract was detected to contain triterpenoid and phenolic compounds evaluated by TLC. The metabolite profile showed that ethyl acetate extract had maximum absorbance at 400-600 nm. The 70 ethanol extract has maximum absorbance at 270-350 nm. The distilled water extract had maximum absorbance at 205-250 nm. © 2023 The Authors, published by EDP Sciences.