Research Background: Heat-stabilised defatted rice bran (HSDRB) is a primary by-product of rice bran oil extraction industry and a nutritious source of protein. However, despite the unique nutritional profile of rice bran protein, the protein-rich by-product, HSDRB is underutilised as a low-value animal feed. Research on protein extraction from HSDRB by enzymatic hydrolysis has attracted the attention of numerous scientists.
View Article and Find Full Text PDFShort-chain fructooligosaccharides (sc-FOS) are prebiotics beneficial to human health, which can be synthesized from raw material containing a high sucrose content. Sugarcane syrup (SS) without molasses removal contains sucrose as a major sugar and is a rich source of several bioactive compounds. The aim of this study is to investigate factors affecting sc-FOS synthesis from SS using commercial enzyme preparations containing fructosyltransferase activity as biocatalysts.
View Article and Find Full Text PDFMusa (ABB group) “Kluai Namwa” bananas (Musa sp.) are widely grown throughout Thailand. Mali Ong is the most popular Kluai Namwa variety used as raw material for sun-dried banana production, especially in the Bangkratum District, Phitsanulok, Thailand.
View Article and Find Full Text PDFA spray-dried cholesterol free salad dressing powder was developed using mixed mono- and diglycerides (MG-DG) as emulsifier. The optimum conditions for enzymatic synthesis of the MG-DG from rice bran oil (RBO) and glycerol (Gly) using lipase was investigated. The synthesis was done by glycerolysis of refined RBO and Gly at molar ratios of 2:1, 2.
View Article and Find Full Text PDFGlutamate decarboxylase (GAD) is an important enzyme in biological metabolisms acting on catalyzing the irreversible α-decarboxylation of L-glutamic acid to γ-aminobutyric acid (GABA) and CO, which was focused in this study. Three rice varieties different in color were germinated at different times and used for crude GAD extraction. Crude GADs with an optimal germination time from germinated black (GBR), red (GRR), and white (GWR) rice were evaluated for enzymatic properties, including the effect of pHs, temperatures, and concentrations of both L-glutamic acid and pyridoxal 5'-phosphate (PLP).
View Article and Find Full Text PDFJ Food Sci Technol
September 2018
This study demonstrated that oligosaccharides from copra meal could be prepared by using a commercial enzyme preparation containing mannanase for use as a prebiotic. The conditions giving the highest hydrolysis rate of the copra meal by the enzyme were pH 4 and temperature of 40 °C with an enzyme to substrate ratio (E/S) of 1092.69 β-mannanase activity unit/g of the dried copra meal.
View Article and Find Full Text PDFUnlabelled: Structural changes involved in the reactivation of peroxidases (PODs) from broccoli and horseradish (HRP) following heat denaturation were investigated by using circular dichroism and absorption spectroscopy. Cooling heat-treated enzymes resulted in rapid refolding of the secondary structure into an inactive structural species, similar in conformation to the native enzyme. Reassociation of heme to the refolded peroxidase, as well as molecular rearrangement of the structure around the heme, occurs during incubation at approximately 25 degrees C and results in the return of biological activity.
View Article and Find Full Text PDFHeat inactivation characteristics differed for acidic (A), neutral (N), and basic (B) broccoli peroxidase. At 65 degrees C, A was the most heat stable followed by N and B. The activation energies for denaturation were 388, 189, and 269 kJ/mol for A, N, and B, respectively.
View Article and Find Full Text PDFThree peroxidase (POD) isoenzymes were purified from a soluble extract of broccoli stems. The acidic and neutral PODs were purified to homogeneity by using ion exchange and hydrophobic chromatography. The basic POD was purified by cation exchange and gel filtration chromatography.
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