cellulase and genipin

A new approach for ionic liquid based enzyme-assisted extraction coupled with in-situ hydrolysis (ILEIH) of geniposide from Eucommia ulmoides Olive barks is presented, in which enzymatic hydrolysis is used in an ionic liquid aqueous medium to prepare genipin. The method relied on the use of single cellulase to the extract and hydrolyze geniposide, which is performed continuously in the same system; genipin is easy in preparation with exempting the isolation and purification of geniposide. The mechanism of ILEIH procedure was discussed in detail to illustrate the advantage of ILEIH in the extraction process. 0.5 mol/L [C6mim]Cl aqueous solution was selected as extraction solvent. The optimum conditions of 140 min treatment time, 19.81 mL/g liquid-solid ratio, 5.15 mg/mL enzyme concentration and 5.0 pH value for the ILEIH process were obtained after investigating by single factor experiments and Box-Benhnken design in terms of the genipin increment. And the first-order kinetic model based on β-glucosidase in the three reaction medium were established to study their impacts on the reaction rate. The proposed ILEIH method was validated by stability, repeatability, and recovery experiments and shows reliable data in the extraction and hydrolysis process. Therefore, this proposed approach is promising for the in-situ production of genipin and should be potentially applied to the obtaining of other active aglycons.

Topics: beta-Glucosidase; Cellulase; Chemistry Techniques, Analytical; Eucommiaceae; Hydrolysis; Ionic Liquids; Iridoids

A continuous process based on the combination of ultrasounds and/or microwaves pretreatments followed by enzymatic hydrolysis and simultaneous extraction (EHSE) has been proposed to recover genipin from Eucommia ulmoides bark. At first, in the pretreatment step, the mixture of 1.0 g dried bark powder and 10 mL deionized water were irradiated by microwave under 500 W for 10 min. Then, in hydrolysis step, the optimal conditions were as follows: 0.5 mg/mL of cellulase concentration, 4.0 pH of enzyme solution, 24 h of incubation time and 40 °C of incubation temperature. After incubation, 10 mL ethanol was added to extract genipin for 30 min by ultrasound. After EHSE treatment, the yield of genipin could reach 1.71 μmol/g. Moreover, scanning electron micrographs illustrated that severe structural disruption of plant was obtained by EHSE. The results indicated that the EHSE method provided a good alternative for the preparation of genipin from Eucommia ulmoides bark as well as other herbs.

Topics: Cellulase; Dose-Response Relationship, Radiation; Ethanol; Eucommiaceae; Hydrogen-Ion Concentration; Hydrolysis; Iridoids; Liquid Phase Microextraction; Microwaves; Plant Bark; Sonication; Temperature

A direct one-pot production of genipin, an iridoid aglycone, from crude gardenia fruit was developed. The method relied on the use of single cellulase to disrupt plant cells and to cleave off sugar molecules simultaneously, thereby enhancing the release of intracellular iridoids and converting geniposide to genipin. During the biocatalysis, eco-friendly ethyl acetate was used to extract the product, providing the partial purification and the minimization of genipin degradation. By using 10 mg/mL cellulase and 24 h-incubation at 50 °C, pH 4, combined with in situ extraction, genipin with good purity was yielded at 58.83 mg/g, which increased 12.38 and 1.72 times compared with those obtained from the procedures without either the aid of enzyme or in situ extraction, respectively. Therefore, this integrated approach is promising for the production of genipin and should be potentially applied to the preparation of other plant aglycones.

Topics: Cellulase; Gardenia; Iridoid Glycosides; Iridoids; Plant Cells; Plant Extracts; Technology, Pharmaceutical