Pengaruh konsumsi kacang merah (Phaseolus vulgaris L.,) terhadap status antioksidan dan profil lipida darah tikus Sprague dawley

RIDHA, Muhammad Fauzan, Prof. Dr. Ir. Y. Marsono, M.S

2009 | Tesis | S2 Ilmu dan Teknologi Pangan

Kacang merah (Phaseolus vulgaris L.) diketahui memiliki sifat hipoglisemik dan hipokolesterolemik yang antara lain disebabkan oleh kandungan antioksidannya. Namun pengolahan kacang merah untuk siap dikonsumsi yang dilakukan secara konvensional (direndam dan direbus) memerlukan waktu lama dan menghasilkan tekstur yang keras. Telah dilakukan penelitian pembuatan kacang merah pratanak dengan perlakuan perendaman dalam berbagai larutan perendam dilanjutkan dengan pemasakan autoclaving. Tujuan penelitian ini adalah untuk mengetahui pengaruh pengolahan kacang merah pratanak terhadap perubahan potensi dan aktivitas antioksidan serta profil lipid darah pada tikus Sprague Dawley. Bahan yang digunakan adalah kacang merah lokal. Kacang merah direndam dalam larutan Na2CO3, larutan NaHCO3 dan larutan (NH4)2CO3 dengan konsentrasi 4,2 % (b/v) masingmasing selama 210, 150 dan 330 menit. Larutan perendam yang memberikan karakter terbaik pada kacang merah pratanak digunakan dalam penelitian berikutnya. Hasil perendaman terbaik dimasak menggunakan pressure cooking (autoclave) pada suhu 121°C selama 125, 135, 145 detik dan dikeringkan dalam oven suhu 65ºC selama 60 menit. Sebagai kontrol, kacang merah direndam dalam air selama 240 menit, direbus mendidih 45 menit dan dikeringkan oven 65oC selama 60 menit. Untuk menentukan variasi pengolahan terbaik dilakukan uji sifat fisik dan sensorik produk setelah dilakukan rehidrasi. Total fenolik dan flavonoid ditentukan sebagai parameter potensi antioksidan dan DPPH sebagai aktivitas antioksidan. Delapan belas ekor tikus jantan jenis Sprague Dawley diinduksi diabetes hiperkolesterolemia dengan injeksi alloxan (80 mg/kg berat badan) dan pemberian pakan hiperkolesterol selama 3 hari. Tiga kelompok tikus masing-masing 6 ekor per kelompok diberi diet standar AIN-93, diet kacang merah pratanak dan diet kacang merah rebus. Pengujian SOD serum dan MDA serum dilakukan pada awal intervensi, setelah dua minggu dan pada akhir penelitian sedangkan profil lipida darah dilakukan pada awal intervensi diet dan setiap minggu sampai akhir penelitian (minggu ke 4). Hasil penelitian menunjukkan kacang merah pratanak yang direndam dalam larutan NaHCO3 4,2% (b/v) selama 150 menit dan dimasak dalam autoclave pada suhu 121°C selama 135 detik menghasilkan karekteristik fisik dan sensoris terbaik. Kacang merah pratanak dengan perlakuan tersebut memiliki aktivitas penangkapan radikal bebas (DPPH) sebesar 42,89%, kadar total fenolik sebesar 40,29 GAE/g db dan total flavonoid sebesar 18,97 mg QE/g db Pada tikus, kacang merah pratanak tersebut mampu meningkatkan kadar SOD serum menjadi 978,93 U/g Hb dan MDA turun menjadi 2,07 mmol/l. Kadar HDL serum naik menjadi 86,75 mg/dl, sedangkan kadar total kolesterol, trigliserida dan LDL serum masingmasing turun menjadi 96,80 mg/dl; 62,13 mg/dl dan 10,18 mg/dl.

Kidney bean (Phaseolus vulgaris L.) has been known to have a hypoglycemic and hypocholesterolemic properties. Antioxidants were reported to give a significant contribution to the properties. However, conventional processing (soaking and boilling) to prepare ready to eat cooked kidney bean is very time consumpting and the cooked bean is still to have a hard texture. A research on the precooking process of kidney been has been conducted. The process including soaking in an several solution and cooking in autoclaving then drying. The objectives of this research were to evaluate the effect of precooking on the antioxidant potention and activity as well as on antioxidant status and blood lipid profile in Sprague Dawley rats. Local kidney beans were used as the material in this study. The bean were soaked in Na2CO3, NaHCO3 and (NH4)2CO3 solution at the concentrations of 4,2% (w/v) with the soaking time of 210, 150 and 330 minutes, respectively. The soaking solution giving the best soaked bean characters were used in the next experiment. Soaked bean were then pressure cooked in autoclave at 121oC for 125, 135, 145 seconds and then dried in oven drying at 65ºC for 60 minutes. As a control, kidney beans were soaked in water 240 minutes, boiled for 45 minutes and then dried in an oven drying at 65ºC for 60 minutes. To determine the best process, physical and sensorial properties of rehydrated cooked bean were analysed.Total phenolic and flavonoid as the parameters for antioxidant potency and DPPH as antioxidant activity were determined. Eighteen Sprague Dawley male rats were induced diabetics hypercholesterolemia by injection of alloxan (80 mg/kg weight) and fed with hypercholesterol diets for 3 days. Three groups of rats, six rats each groups were given by standard diet AIN-93, precooked and boiled kidney bean diet. The SOD and MDA serum were determined in the early and after two weeks intervention and at the end of the study. The blood lipids profile were determined at the early of diet intervention and each week until the end of the research (fourth week). It was found that precooked kidney bean soaked in NaHCO3 solution 4,2% (b/v) for 150 minutes and precooked in autoclave at 121oC for 135 seconds resulted in precooked bean with the best physical and sensorial properties. Precooked kidney bean had the scavenging free radicals activity (DPPH) of 42,89%, total phenolic of 40,29 GAE/g db and total flavonoid of 18,97 mg QE/g. Precooked kidney bean increased SOD serum to 978,93 U/g Hb and the MDA decreased to 2,07 mmol/l. The HDL serum decreased to 86,75 mg/dl but cholesterol total, trigliserida and LDL serum decreased to 2,07 mmol/l; 96,80 mg/dl; 62,13 mg/dl and 10,18 mg/dl respectively.

Kata Kunci : Kacang merah (Phaseolus vulgaris L),Pratanak,Antioksidan,Profil lipida darah,Tikus Sprague dawley,Diabetes hiperkolesterolemia, Kidney bean (Phaseolus vulgaris L.), Precooked, Antioxidant, Blood lipid profile, Sprague Dawley rats, Diabets hiperkolesterole