FRAKSINASI PROTEIN pI 5 DAN pI 8 BIJI CARICA (Carica pubescens) DENGAN EKSTRAKSI BASA SERTA KAJIANNYA SEBAGAI BAHAN FORTIFIKASI PANGAN

MUHAMMAD SYARIF H, Dr. Tri Joko Raharjo, M.Si.; Dr. Endang Astuti, M.Si.

2016 | Skripsi | S1 KIMIA

Telah dilakukan fraksinasi protein pI 5 dan pI 8 biji buah carica (Carica pubescens) serta kajian potensinya sebagai bahan fortifikasi. Penelitian ini bertujuan menentukan kandungan gizi, melakukan ekstraksi protein pada suasana basa (pH 12), fraksinasi protein pada pI 5 dan pI 8, serta mengidentifikasi kandungan asam amino esensialnya. Penentuan kandungan gizi biji carica dilakukan melalui analisis proksimat. Kadar air ditentukan melalui metode gravimetri, kadar abu dengan pengabuan pada temperatur 550 °C, kadar lemak melalui ekstraksi padat-cair (Soxhletasi), kadar protein kasar melalui metode Kjeldhal, dan kadar karbohidrat melalui by different. Asam lemak yang terkandung dalam minyak biji carica dianalisis menggunakan KG-SM melalui derivatisasi BF3-metanol. Sampel biji carica bebas lemak diekstraksi pada pH 12. Fraksinasi protein melalui pengendapan isoelektrik pada pI 5 dan pI 8. Asam amino dianalisis menggunakan KCKT fasa balik dengan detektor flouresensi. Biji carica (Carica pubescens) mengandung air 4,64 ± 0,15 %, abu 4,87 ± 0,07 %, lemak 35,38 ± 0,71 %, protein 28,28 ± 1,01 %, dan karbohidrat 26,83 %. Minyak biji carica mengandung asam oleat 71,08%, asam palmitat 15,62 %, asam linoleat 9,70 %, dan asam stearat 3,59 %. Fraksi pI 5p dan pI 8 (pengendapan pertama) sebesar 87,41 % dan 9,01 %. Fraksi pI 5s (pengendapan kedua supernatan sisa fraksi pI 8) sebesar 77,14 %. Total asam amino esensial pada fraksi protein pI 5s sebesar 44,41 %, fraksi pI 5p sebesar 35,44 %, dan fraksi pI 8 sebesar 0,63 %. Fraksi protein pI 5 berpotensi sebagai bahan fortifikasi. Fraksi pI 5s memenuhi kebutuhan asam amino esensial sesuai ketentuan FAO/WHO tahun 1985 untuk usia dewasa dan anak-anak usia prasekolah sedangkan fraksi pI 5p hanya memenuhi kebutuhan asam amino esensial untuk usia dewasa.

Fractination of proteins pI 5 and pI 8 of carica (Carica pubescens) seeds and study for food fortification have been done. This research aims to determine the nutrient content of the seeds, extract of the protein at alkaline pH, fractionate using pI 5 and pI 8, and identify the essential amino acid content. The determination of nutrition content carica seed was done by proximate analysis. The water content was determined by gravimetric, ash content was determined by ashing sample at 550 °C, fat content was determined by Soxhletation, protein content was determined by Kjeldhal method and carbohydrates was calculated by different. Fatty acids contained in carica seeds oil was analyzed by using GC-MS through derivatization BF3-methanol. Protein was extracted from fat-free samples in alkaline conditions at pH 12. Fractination of protein was carried out by isoelectric precipitation at pI 5 and pI 8. Amino acid was analyzed by using reverse phase HPLC with flourescence detector. The carica (Carica pubescens) seeds contain 4.64 ± 0.15 % of water, 4.87 ± 0.07 % of ash, 35.38 ± 0.71 % of fat, 28.28 ± 1.01 % of protein and 26.83 % of carbohydrates. Carica seeds oil contains 71.08 % of oleic acid, 15.62 % of palmitic acid, 9.70 % of linoleic acid and 3.59 % of stearic acid. Fraction pI 5p and pI 8 (first precipitation) was recovered 9.01 % and 87.41 %. Fraction pI 5s (second precipitation remaining of supernatant fraction pI 8) was recovered 77.14 %. The essential amino acids contain 44.41 % of fraction pI 5s, 35.44 % of fraction pI 5p, and 0.63 % of fraction pI 8. Fraction pI 5 is to be used protential as food fortification material. Fraction pI 5s are fulfilling essential amino acids requirement in the regulation FAO/WHO 1985 for adult and child preschool while fraction pI 5p only for adult.

Kata Kunci : Carica (Carica pubescens) seeds, fatty acids, alkaline extraction, isoelectric precipitation, fortification