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"It has been known that isoflavone have biological activities such as antioxidant, antibacteria, antimutagenesis, and anticancer. Isoflavone aglycone uses such as genestein, daidzein and glycitein are li ited since they are unstable and uneasily to dissolve in water...."

"ABSTRACTCyclodextrin glycosyltransferase (CGTase) catalyzes an intermolecular transglycosylation reaction to produce functional oligosaccharides or glycosides, which can be used in several industries. In this study, the p19bBC recombinant cells containing CGTase gene from Bacillus circulans A11 were used for synthesizing CGTase. The maximum expression was obtained when the p19bBC cells were cultured at 37oC for 24 h with 0.2 mM IPTG. The recombinant CGTase was purified up to 6-fold by 5% (w/v) starch adsorption and the specific activity of enzyme was 1.08x104 units/mg with a 71% yield. The 72-kDa relative molecular mass of purified enzyme was determined by 10% SDS-PAGE. In addition, the acceptor specificity of enzyme was investigated from transglycosylation reaction using β-cyclodextrin as glycosyl donor and various saccharides and flavonoids as acceptors. Among the group of saccharide acceptors, glucose gave the highest activity, followed by maltose and mannose. Within the flavonoid group, hesperidin gave the highest activity with 13.5% as compared to glucose. Due to the broad range of bioactivities of hesperidin flavonoid, and also, the possibility of new glycoside products, this study suggested that using hesperidin as an acceptor is far superior to the saccharides in terms of further applications."

"Enzim sukrosafosforilase termasuk dalam kelompok enzim glukosiltransferase. yang dapat mengkatalisis sukrosa dan fosfat menjadi Ɗ-fructose dan α-Ɗ-glucose 1-phospate. SPase berperan dalam pemindahan gugus glukosil ke sejumlah senyawa (transglikosilasi). Reaksi transglkosilasi dapat dimanfaatkan untuk meningkatkan stabilitas kimia dan memperbaiki karakteistik senyawa bioaktif.Tujuan penelitian ini adalah melakukan pemurnian SPase rekombinan yang dihasilkan oleh Escherichia coli BL21DE yang membawa gen penyandi sukrosafosforilase asal Leuconostoc mesenteroides dengan kromatografi affinitas pada kondisi optimum dan menguji aktivitas SPase rekombinan dengan metode spektofotometri. Pada esei enzimatis, SPase direaksikan menggunakan substrat sukrosa dan produk akhirnya diukur sebagai NADPH pada 340 nm.Hasil SDS PAGE ,menunjukan SPase rekombinan berhasil dimurnikan dengan berat molekul yang telah diidentifikasi dari penelitian sebelumnya adalah 55-57 kDa. Hasil esei aktivitas enzimatis menggunakan metode spektofotometri menunjukan bahwa SPase rekombinan ini terbukti aktif meskipun aktivitasnya lebih rendah dibandingkan SPase standar dari Leuconostoc mesenteroides.

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Sucrose phosphorylase belongs to glycosiltransferase which catalyze sucrose and phospate become Ɗ-fructose dan α-Ɗ-glucose 1-phospate. SPase has role in transglucosylation to increase chemical stability and repair characteristic of bioactive compound.

The object of this research are purification SPase recombinant from E. coli BL21DE which carries out SPase gene from Leuconostoc mesenteroides. Affinity chromatography is used to purify SPase recombinant in optimum condition and try assay enzymatic activity of SPase recombinant with spectrophotometry method. SPase recombinant use sucrose as substrate and the final product is measured as NADPH at 340 nm.

SDS Page reveal that SPase recombinant is succeeded to be purified with molecular mass 55-57 kDa based on previous research. SPase recombinant has lower enzymatic activity than SPase from Leuconostoc mesenteroides."