A new high-performance liquid chromatographic method for the quality control of bioconverted Mori Folium extracts with appropriate marker compounds related to antidiabetes

A HPLC method was developed to assess the enhanced bioactivity of bioconverted Mori Folium (MF) extract and to apply a quality-control system. Liquid-liquid extraction was applied to observe changes in chemical composition through enzymatic bioconversion. The ethyl acetate layer was used for quality control of the anti-diabetic functional MF product. A high-performance liquid chromatography method was developed to analyze five marker compounds (syringaldehyde, trans-caffeic acid, morin 3-O-β-D-glucopyranoside, astragalin, and moracin M 3′-O-β-glucopyranoside) within 60 min. Optimized sample preparation was sonication for 44 min and a water-to-material ratio of 102.5 mL/g by response surface methodology. Comparing MF water extract, trans-caffeic acid and syringaldehyde contents were increased 1.89 times and 2.70 times at Viscozyme-bioconverted material by applying the developed method. This HPLC method can be used to control the quality of bioconverted MF based on suitable bioactive markers and also applied to develop anti-diabetic functional foods containing Mori Folium.

Efficient bioconversion of high-concentration D-fructose into D-mannose by a novel N-Acyl-D-glucosamine 2-epimerase from Thermobifida halotolerans

The synthesis of mannose is of great value because it is the only glyconutrient for clinical application. Here, we performed the enzymatic bioconversion of D-fructose to D-mannose using a recombinant...

Enzymatic bioconversion of feather waste with keratinases of Bacillus cereus PCM 2849

Enzymatic preparation from culture of keratinolytic Bacillus cereus PCM 2849 was applied for hydrolysis of whole chicken feathers, after sulphitolytic pretreatment. This process was optimized using a three-factor Box-Behnken design, where the effect of substrate concentration, sulphite concentration during pretreatment and reaction temperature was evaluated on the release of amino acids. Obtained results revealed the highest impact of reaction temperature, followed by substrate content and sulphite during pretreatment. Optimal process conditions were established, i.e. temperature 44.4°C, feathers 4.7% and treatment with 25.3 mM sulphite. Amino acid composition of the obtained hydrolysate was analyzed. Glutamic acid (9.21 g·kg−1) and proline were dominant, however significant amount of branched-chain amino acids was also observed. The FTIR analysis of residual substrate revealed the cleavage of disulphide bonds in keratin through the presence of thioester residues. The absence of reduced cysteine residues was confirmed, along with minor changes in proportions of keratin substructures.