Author:
Purwandhani Siti Nur,Utami Tyas,Millati Ria,Rahayu Endang Sutriswati
Abstract
Folate is a B vitamin that participates in one-carbon transfer reactions of metabolism process, particularly purine and pyrimidine biosynthesis (DNA and RNA). Some strains of lactic acid bacteria are known to produce folic acid through the conversion of guanosine tri phosphate and the presence of precursor p-amino benzoic acid and glutamic acid. In this study, skim milk was fermented using Lactobacillus plantarum Dad-13, G-3, and H-1 to increase the levels of folate. Fermentation was conducted at 37 °C for 18 hours. The aims of this study were to investigate the population of L. plantarum during fermentation period, the change in pH and the levels of folate in fermented milk. The results showed that during the fermentation period using L. plantarum G-3, H-1, and Dad-13 cell count increased from 107 to 108 for G-3 and H-1, while Dad-13 into 109. The pH value decreased and the levels of folic acid in early fermentation increased rapidly but after approaching the end of fermentation, it began to stagnate. The folate level of skim milk was 23.70 ± 3.25 µg/L. Increased levels of folate in fermented milk after 18 hours fermentation using L. plantarum Dad-13, G-3, and H-1 were 32.04 ± 1.85 µg/L (135.19%), 28.21 ± 0.28 µg/L (118.99%), and 25.13 ± 1.27 µg/L (106.03%), respectively.ABSTRAKFolat merupakan vitamin B yang berpartisipasi dalam reaksi transfer satu-karbon dalam proses metabolisme, terutama biosintesis purin dan pirimidin (DNA dan RNA). Beberapa strain bakteri asam laktat diketahui mampu memproduksi asam folat melalui konversi guanosin tri pospat dan dengan adanya prekursor p-amino benzoat serta asam glutamat. Pada penelitian ini, susu skim difermentasi menggunakan Lactobacillus plantarum Dad-13, G-3, dan H-1 untuk meningkatkan kadar asam folatnya. Fermentasi dilakukan pada 37 °C selama 18 jam. Tujuan penelitian ini adalah untuk mengetahui pola pertumbuhan sel, perubahan pH, dan kadar asam folat susu selama fermentasi. Hasil penelitian menunjukkan bahwa selama fermentasi menggunakan L. plantarum Dad-13, G-3, dan H-1 jumlah sel meningkat dari 107 menjadi 108 untuk G-3 dan H-1, sedangkan Dad-13 menjadi 109. Nilai pH mengalami penurunan dan kadar asam folat pada awal fermentasi meningkat dengan cepat tapi setelah mendekati akhir fermentasi mulai stagnan. Kadar asam folat susu skim adalah 23,70 ± 3,25 µg/L. Dibandingkan dengan kadar asam folat susu skim, peningkatan kadar folat susu fermentasi setelah 18 jam fermentasi dengan starter L. plantarum Dad-13, G-3, dan H-1 secara berturut-turut 32,04 ± 1,85 µg/L (135,19%), 28,21 ± 0,28 µg/L (118,99%), dan 25,13 ± 1,27 µg/L (106,03%).