Skripsi

Uji Fitokimia dan Aktivitas Inhibisi Enzim Alfa-Glukosidase in vitro oleh Ekstrak N-Heksana dan Etil Asetat dari Bunga Kecombrang (Etlingera elatior) = Phytochemical Screening and In Vitro Alpha-Glucosidase Inhibitory Activity of n-Hexane and Ethyl Acetate Extracts of Torch Ginger (Etlingera elatior) Flowers.

Latar Belakang: Diabetes Melitus tipe 2 ditandai hiperglikemia kronis. Salah satu pendekatan terapinya adalah menghambat enzim alfa-glukosidase usus yang berperan langsung dalam pemecahan karbohidrat menjadi glukosa. Penghambatan enzim tersebut penting karena dapat memperlambat penyerapan glukosa sehingga menurunkan kadar glukosa postprandial tanpa bergantung pada kerja insulin. Acarbose merupakan obat yang digunakan secara klinis, namun efek samping gastrointestinal mendorong pencarian sumber alami dengan potensial serupa. Indonesia memiliki keanekaragaman hayati yang berpotensi sebagai sumber agen antidiabetik alami. Bunga kecombrang (Etlingera elatior) mengandung berbagai metabolit bioaktif, namun data aktivitas inhibisi dari pelarut n-heksana etil asetat masih terbatas. Metode: Penelitian in vitro eksperimental menggunakan ekstrak n-heksana dan etil asetat bunga kecombrang hasil maserasi. Dilakukan skrining (flavonoid, saponin, tannin, glikosida, triterpenoid/steroid, dan alkaloid) serta uji inhibisi alfa-glukosidase pada tujuh konsentrasi dengan acarbose sebagai kontrol positif. Persen inhibisi diplot terhadap log konsentrasi dan dianalisis dengan regresi linier untuk memperoleh nilai IC50. Hasil: Fitokimia menunjukkan ekstrak etil asetat positif flavonoid dan triterpenoid, sedangkan ekstrak n-heksana positif triterpenoid. Nilai IC50 (Mean ± SD) masingmasing: n-heksana 78,553 ± 6,067 ppm, etil asetat 61,905 ± 2,357 ppm, dan acarbose 17,026 ± 6,026 ppm. Kesimpulan: Ekstrak etil asetat bunga kecombrang (Etlingera elatior) mengandung flavonoid dan triterpenoid, sedangkan ekstrak n-heksana hanya mengandung triterpenoid. Kandungan senyawa tersebut berperan dalam aktivitas penghambatan enzim alfaglukosidase. Aktivitas inhibisi ekstrak etil asetat lebih tinggi dibandingkan n-heksana, namun keduanya masih lebih rendah dibandingkan acarbose.
Kata Kunci: alfa-glukosidase, Etlingera elatior, fitokimia, IC50, in vitro


Introduction: Type 2 Diabetes Mellitus is characterized by chronic hyperglycemia. One therapeutic approach is to inhibit the intestinal α-glucosidase enzyme, which plays a direct role in the breakdown of carbohydrates into glucose. Inhibition of this enzyme is important because it can slow glucose absorption and thereby reduce postprandial blood glucose levels independently of insulin action. Acarbose is a clinically used drug; however, its gastrointestinal side effects have driven the search for natural sources with similar potential. Indonesia’s biodiversity offers various natural resources that may serve as antidiabetic agents. Torch ginger (Etlingera elatior) contains diverse bioactive metabolites, but data regarding the α-glucosidase inhibitory activity of its n-hexane and ethyl acetate extracts remain limited. Method: An experimental in vitro study used n-hexane and ethyl acetate extracts of E. elatior flowers obtained by maceration. Phytochemical screening (flavonoids, saponins, tannins, glycosides, triterpenoids/steroids, alkaloids) was performed. Alpha-glucosidase inhibitory activity was assessed at seven concentrations with acarbose as the positive control. Percent inhibition was plotted against log concentration; linear regression was used to obtain IC50. Results: Phytochemistry showed the ethyl acetate extract was positive for flavonoids and triterpenoids, while the n-hexane extract was positive for triterpenoids. IC50 values (Mean ± SD) were: n-hexane 78,553 ± 6,067 ppm, ethyl acetate 61,905 ± 2,357 ppm, and acarbose 17,026 ± 6,026 ppm. Conclusion: The ethyl acetate extract of Etlingera elatior (torch ginger) contains flavonoids and triterpenoids, while the n-hexane extract contains only triterpenoids. These compounds are suggested to contribute to the inhibition of the α-glucosidase enzyme. The inhibitory activity of the ethyl acetate extract was higher than that of the nhexane extract but remained lower than that of acarbose.
Keywords: alpha-glucosidase, Etlingera elatior, phytochemistry, IC50, in vitro