Bioaktivitas Fraksi Etil Asetat dan Aktivitas Antidiabetes Senyawa Fenolik dari Daun Sirih (Piper betle L.)

Abstract

This research studied the bioactivities of ethyl acetate fraction of methanol extract of betel leaves and antidiabetic activities of phenolic compounds from betel leaves. The extraction was done by macerating the betel leaf dry powder and using the polarity-based fractionation procedure. The cytotoxic activity of the fraction was tested by using brine shrimp lethality method. Lethal concentration of the fraction showed LC50 values of 3.92 ppm. Antioxidants were tested using 2,2-diphenyl-1-picrylhydrazyl scavenging method, and an in vitro antidiabetic test was performed using α-glucosidase inhibitory method. Both tests showed IC50 value of 2.91 ppm and 48.55 ppm respectively. The antimicrobial test against three types of microbes which was performed by a disc-diffusion method showed negative results against the gram-negative Escherichia coli, and the ethyl acetate fraction concentration was as high as 120 ppm. However, the test showed positive results against the gram-positive bacteria Staphylococcus aureus and mushroom Candida albicans, and the concentration of fraction was as low as 30 ppm. The isolation of phenolic compounds from ethyl acetate fraction by using column chromatography and the application of preparative procedures were successful in obtaining a phenol compound derivative identified as 2-hydroxychavicol based on the data from the infrared, UV-visible, and 1D or 2D proton and carbon NMR spectrophotometry. Antidiabetic in vitro assay of the isolate has been done with α-glucosidase inhibitory method. The IC50 value of the isolate was 72,87 ppm which was higher than IC50 of the fraction. This indicates that there were synergism between the components of ethyl acetate fraction causing stronger inhibitory activity against α-glukosidase enzyme compared with a single compound 2-hidroxychavicol.

Penelitian bioaktivitas fraksi etil asetat ekstrak metanol daun sirih dan aktivitas antidiabetes senyawa fenolik dari daun sirih telah dilakukan. Metode ekstraksi yang digunakan adalah maserasi serbuk kering daun sirih dan fraksinasi berdasarkan polaritas. Uji sitotoksik fraksi menggunakan metode brine shrimp lethality telah dilakukan. Lethal concentration fraksi menunjukkan nilai LC50 sebesar 3,92 bpj. Uji antioksidan dengan metode peredaman 2,2-diphenyl-1-picrylhydrazyl dan uji antidiabetes dengan metode peredaman α-glukosidase menunjukkan nilai Inhibitory Concentration, IC50 berturut-turut 2,91 bpj dan 48,55 bpj. Uji antimikrobial terhadap tiga jenis mikroba dengan metode disc-diffusion menunjukkan hasil negatif terhadap bakteri gram negatif Escherichia coli sampai konsentrasi 120 bpj, namun menunjukkan hasil positif terhadap bakteri gram positif Staphylococcus aureus dan jamur Candida albicans pada konsentrasi fraksi serendah 30 bpj. Kromatografi kolom fraksi etil asetat ekstrak metanol daun sirih dan penerapan prosedur preparatif terhadap fraksi-fraksi yang diperoleh berhasil mengisolasi turunan senyawa fenol yang teridentifikasi sebagai 2-hidroksichavikol berdasarkan data spektrofotometri infra merah, ultra-violet, dan data resonansi magnetik inti proton dan karbon, satu dan dua dimensi. Uji antidiabetes terhadap isolat telah dilakukan dengan metode peredaman α-glukosidase. Isolat memiliki nilai IC50 sebesar 72,87 bpj. Hal ini menunjukkan bahwa terdapat sinergisme antar komponen penyusun fraksi yang menyebabkan fraksi etil asetat ekstrak metanol daun sirih memiliki kemampuan inhibisi yang lebih kuat terhadap enzim α-glukosidase dibandingkan senyawa tunggal 2-hidroksichavikol.