Karakterisasi lintah laut (Discodoris sp) sebagai antioksidan dan antikolesterol

Abstract

Sea slug (Discodoris sp) is a member of nudibranch marine invertebrate usually called as non shell gastropod. Sea slug has been used by Bajo People in Buton Island as aphrodisiac and food supplement. The general objectives of this research were to isolate and characterize the antioxidant and anticholesterol activity of sea slug and to study the possibility for functional food development. The specific objectives of this research were (1) to determine the yield and the antioxidant activity with various solvents and its chemical group, (2) to examine dry powder sea slug as an antioxidant related to cholesterol formation of rabbit blood, (3) and to investigate atheroma/plaque formation of rabbit blood vessels, (4) to investigate toxicopathological effects of dry sea slug powder against liver and kidney. The research was conducted in four stages; (1) sampling of sea slug and dry sample preparation, (2) extraction of dry powder by applying various solvent (non polar, semi polar and polar), (3) antioxidant activity test by diphenylpicryl hydrazyl (DPPH), Nitrobluetetrazolium (NBT) method and crude extract-selected chemical test, (4) in vivo test against sixteen 5 months old male New Zealand White rabbits. The treatments included (1) negative control feed by RB-12 (K-), (2) positive control feed by RB-12 and cholesterol 0.2% (K+), (3) simvastatin feed by RB-12, cholesterol 0.2% and Simvastatin 0.625 mg/indivividual daily (S), (4) Discodoris sp feed by sea slug powder at dosage of 4 g/individual daily (average of weight 2.5 kg), RB-12 and cholesterol 0.2%. Total cholesterol, triglyceride, HDL, and LDL of blood serum were determined at 0, 4, 8 and 12 weeks. At the end of experiment, SGOT and SGPT were tested and histopathological alteration of heart blood vessel liver and kidney was observed. Dry sea slug powder contained protein of 49.60%; fat of 4.58%; ash of 11.74%; acid-insoluble ash of 1.9%; moisture of 15.25%; crude fiber of 0.45%, and carbohydrate of 18.73%. Mercury (Hg), lead (Pb), Cadmium (Cd) were not detected when analyzed by AAS. Methanol extract provided the highest yield i.e 5.12% and IC50 of 781.23 ppm for whole sample and 1657.07 ppm for mantle while with NBT method resulted IC50 89.44%. Methanol extract contained alkaloid, steroid, saponin, free amino acids, carbohydrat and phenol. Feeding 4 g/individual/day dry sea slug powder onto rabbit for 12 weeks decreased total cholesterol from 572.40mg/dl to 69.75 mg/dl, LDL (low density lipoprotein) from 435.20 mg/dl to 17.50 mg/dl, triglyceride from 210.35 mg/dl to 40.87 mg/dl. In addition, HDL (high density lipoprotein) increased from 18.95 to 103.23 mg/dl (α = 0.05). Dry sea slug powder also suppressed fat and hydropic degeneration of the liver and prevented formation of plaque/atheroma of heart blood vessel. However it protein sedimentation occurred on kidney glomerulus. The research concluded that dry sea slug powder with it chemical contents showed potential antioxidant and anticholesterolemia agents and could prevent the formation of fat on the liver and plaque on the heart blood vessel.

Lintah laut (Discodoris sp) adalah salah satu jenis invertebrata laut yang termasuk nudibranch dan sering juga disebut dengan istilah siput/keong tanpa cangkang. Lintah laut ini telah dimanfatkan oleh masyarakat Bajo di Kepulauan Buton sebagai aprodisiaka dan peningkat stamina tubuh. Tujuan umum dari penelitian ini adalah untuk mengisolasi dan karakterisasi antioksidan serta antikolesterol yang dihasilkan oleh lintah laut serta mengkaji kemungkinan pengembangannya sebagai pangan fungsional. Tujuan khusus penelitian ini untuk (1) menentukan rendemen dan aktivitas antioksidan dengan berbagai pelarut serta kelompok senyawa kimia ekstrak lintah laut kering, (2) mengetahui khasiat antioksidan lintah laut yang mengandung bahan lain dikaitkan dengan pembentukan kolesterol pada darah kelinci, (3) mengetahui aktivitas antioksidan dan bahan lain yang terdapat pada lintah laut yang berkaitan dengan pembentukan ateroma/plak pada pembuluh darah kelinci, (4) mengetahui efek toksikopatologis antioksidan dan bahan lain yang terdapat pada lintah laut terhadap organ hati dan ginjal. Penelitian dilakukan dalam 4 tahap yaitu: (1) Pengambilan contoh lintah laut dan persiapan contoh kering (2) Ekstraksi dengan metode Quinn menggunakan pelarut bertingkat (nonpolar, semi polar, polar), (3) Uji aktivitas antioksidan menggunakan metode diphenylpicryl hydrazyl DPPH dan Nitrobluetetrazolium (NBT) serta uji kimia ekstrak kasar terpilih, (4) Uji in-vivo menggunakan 16 ekor kelinci ras New Zealand White jenis kelamin jantan yang berumur 5 bulan dan dibagi menjadi 4 perlakuan. Perlakuan kontrol negatif diberi ransum pakan RB-12 (K-), Perlakuan kontrol positif diberi ransum RB-12 dan kolesterol 0,2% (K+), Perlakuan Simvastatin diberi ransum RB-12, kolesterol 0,2% dan Simvastatin 0,625 mg per ekor/hari (S), Perlakuan Discodoris sp dengan penambahan bubuk lintah laut 4 g per ekor/hari (berat badan rata-rata 2,5 kg), ransum RB-12 dan kolesterol 0,2%. Pengamatan kolesterol total, trigliserida, HDL, dan LDL serum darah kelinci dilakukan pada minggu ke-0, 4, 8, dan 12. Pada akhir percobaan dilakukan uji SGOT dan SGPT serta pengamatan perubahan histopatologis organ hati, pembuluh darah jantung dan ginjal.