Kemampuan antioksidatif ekstrak etanol kacang panjang (Vigna sinensis) dan kacang merah (Phaseolus vulgaris) pada tikus diabetes-hiperkolesterolemia

AFFANDI, Dian Rachmawanti, Prof.Dr.Ir. Y. Marsono

2006 | Tesis | S2 Ilmu dan Teknologi Pangan

Tujuan penelitian ini adalah (i) untuk menentukan hubungan antara sifat antioksidatif ekstrak etanol kacang panjang (Vigna sinensis) dan kacang merah (Phaseolus vulgaris) dengan sifat hipoglisemik dan hipokolesterolemik kacang, (ii) untuk menentukan efek konsumsi ekstrak kacang dengan profil lipid, kadar glukosa, dan kadar malondialdehid (MDA) serum tikus diabeteshiperkolesterolemia. Masing-masing kacang digiling kemudian diekstrak dengan pelarut etanol 96% selama 3x24 jam diikuti dengan evaporasi untuk mendapatkan senyawa flavonoid (fenolik). Aktivitas antioksidan kacang dan vitamin E ditentukan dengan analisis reducing power. Banyaknya ekstrak setara dengan vitamin E 50 mg/kg diet, diberikan kepada tikus dengan berdasar perhitungan yang membandingkan aktivitas antioksidatif ekstrak kacang dengan vitamin E. Dipilih 37 ekor tikus Sprague Dawley dan diberi pakan diet hiperkolesterol selama 8 hari kemudian diinduksi diabetes dengan injeksi aloksan (80 md/kg berat badan). Tikus dibagi menjadi empat kelompok, masing-masing terdiri dari 9 tikus (kecuali plasebo terdiri dari 10 tikus) dan diberi diet standar selama 4 minggu. Tiak kelompok diberi force feed berupa vitamin E, ekstrak kacang panjang, ekstrak kacang merah, dan aquades (plasebo). Kadar glukosa dan profil lipid serum dianalisis tiap minggu selama penelitian, sedangkan kadar MDA serum ditentukan pada awal, tengah dan pada akhir penelitian. Diketahui bahwa sifat hipoglisemik & hipokolesterolemik ekstrak etanol kacang panjang dan kacang merah sebanding dengan kemampuan antioksidatifnya. Ekstrak etanol kacang merah lebih baik daripada kacang panjang. Ekstrak etanol kacang merah mampu menurunkan kadar glukosa, total kolesterol, HDL & LDL kolesterol, trigliserida, & MDA serum tikus diabeteshiperkolesterolemia.

The objective of this study were (i) to determine correlations between antioxidative properties of ethanol extract of yardlong and kidney beans with hypoglycemic and hypocholesterolemic properties of the beans, (ii) to determine effects of consumption of the extracts on lipid’s profiles, glucose concentration and malondialdehyde (MDA) of serum in hypercholesterolemia diabetic rats. The beans were milled and then extracted with ethanol 96% for 3x24 hours followed by evaporation to get flavonoid (phenolic) extract. The antioxidant activity of the extract and vitamin E were determined, using reducing analysis method. The quantity of the extract equal to 50 mg/kg diet of vitamin E to be given to the rats were calculated based on the antioxidative activity of the extract compared to the vitamin E. Thirty seven of Sprague dawley rats were selected and fed with hypercholesterol diet for 8 days then were diabetic induced with alloxan injection (80 mg/kg body weight). They were divided into four groups of nine rats (except for placebo group was 10 rats) and given standard diet for 4 weeks. Each group was forced feed with vitamin E, yardlong bean extract, kidney bean extract and aquadest (placebo). Serum glucose and profile lipids of the blood were analyzed every week during the experiment and MDA were determined at the beginning, in the middle and in the end of the experiment. It was found that the hypoglycemic and hypocholesterolemic properties of yardlong and kidney bean ethanol extract were proportional with their antioxidative abilities. The ethanol extract of kidney bean was better than yardlong bean. Ethanol extract of the kidney bean decreased serum glucose, total cholesterol, HDL & LDL cholesterol, triglyceride, and serum MDA of hypercholesterolemia diabetic rats.

Kata Kunci : Diabetes,Hiperkolesterolemia,Kacang Tanah,Antioksidan, diabetes, hypercholesterolemia, antioxidant, beans