- Covalent Immobilization of Naringinase over Two-Dimensional 2D Zeolites and its Applications in a Continuous Process to Produce Citrus Flavonoids and for Debittering of Juices
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The crude naringinase from Penicillium decumbens and a purified naringinase with high α-L-rhamnosidase activity could be covalently immobilized on two-dimensional zeolite ITQ-2 after surface modification with glutaraldehyde. The influence of pH and temperature on the enzyme activity (in free and immobilized forms) as well as the thermal stability were determined using the specific substrate: p-nitrophenyl-alpha-L-rhamnopyranoside (Rha-pNP). The crude and purified naringinase supported on ITQ-2 were applied in the hydrolysis of naringin, giving the flavonoids naringenin and prunin respectively with a conversion '90 percent and excellent selectivity. The supported enzymes showed long term stability, being possible to perform up to 25 consecutive cycles without loss of activity, showing its high potential to produce the valuable citrus flavonoids prunin and naringenin. We have also succeeded in the application of the immobilized crude naringinase on ITQ-2 for debittering grapefruit juices in a continuous process that was maintained operating for 300 h, with excellent results.
- Carceller, Jose Miguel,Martínez Galán, Julián Paul,Monti, Rubens,Bassan, Juliana Cristina,Filice, Marco,Yu, Jihong,Climent, María J.,Iborra, Sara,Corma, Avelino
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p. 4502 - 4511
(2020/06/08)
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- Two trifunctional leloir glycosyltransferases as biocatalysts for natural products glycodiversification
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Two promiscuous Bacillus licheniformis glycosyltransferases, YdhE and YojK, exhibited prominent stereospecific but nonregiospecific glycosylation activity of 20 different classes of 59 structurally different natural and non-natural products. Both enzymes transferred various sugars at three nucleophilic groups (OH, NH2, SH) of diverse compounds to produce O-, N-, and S-glycosides. The enzymes also displayed a catalytic reversibility potential for a one-pot transglycosylation, thus bestowing a cost-effective application in biosynthesis of glycodiversified natural products in drug discovery.
- Pandey, Ramesh Prasad,Bashyal, Puspalata,Parajuli, Prakash,Yamaguchi, Tokutaro,Sohng, Jae Kyung
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supporting information
p. 8058 - 8064
(2019/10/14)
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- Regioselective O-glycosylation of flavonoids by fungi Beauveria bassiana, Absidia coerulea and Absidia glauca
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In the present study, the species: Beauveria bassiana, Absidia coerulea and Absidia glauca were used in biotransformation of flavones (chrysin, apigenin, luteolin, diosmetin) and flavanones (pinocembrin, naringenin, eriodictyol, hesperetin). The Beauveria bassiana AM 278 strain catalyzed the methylglucose attachment reactions to the flavonoid molecule at positions C7 and C3′. The application of the Absidia genus (A. coerulea AM 93, A. glauca AM 177) as the biocatalyst resulted in the formation of glucosides with a sugar molecule present at C7 and C3′ positions of flavonoids skeleton. Nine of obtained products have not been previously reported in the literature.
- Sordon, Sandra,Pop?oński, Jaros?aw,Tronina, Tomasz,Huszcza, Ewa
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- An alkali tolerant α-L-rhamnosidase from Fusarium moniliforme MTCC-2088 used in de-rhamnosylation of natural glycosides
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Analkali tolerant α-L-rhamnosidase has been purified to homogeneity from the culture filtrate of a new fungal strain, Fusarium moniliforme MTCC-2088, using concentration by ultrafiltration and cation exchange chromatography on CM cellulose column. The molecular mass of the purified enzyme has been found to be 36.0 kDa using SDS-PAGE analysis. The Km value using p-nitrophenyl-α-L-rhamnopyranoside as the variable substrate in 0.2 M sodium phosphate buffer pH10.5 at50 °C was 0.50 mM. The catalytic rate constant was15.6 s?1giving the values of kcat/Km is 3.12 × 104M?1 s?1. The pH and temperature optima of the enzyme were 10.5 and 50 °C, respectively. The purified enzyme had better stability at 10 °C in basic pH medium. The enzyme derhamnosylated natural glycosides like naringin to prunin, rutin to isoquercitrin and hesperidin to hesperetin glucoside. The purified α-L-rhamnosidase has potential for enhancement of wine aroma.
- Kumar, Dhirendra,Yadav, Sarita,Yadava, Sudha,Yadav
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- Preparation of Prunin and derivative thereof and application of Prunin derivative in drugs for relieving cough and reducing phlegm
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The invention relates to preparation of a Prunin derivative and application thereof in drugs for relieving a cough and reducing phlegm. The Prunin derivative is obtained by introducing glycosyl or aliphatic chains or an amine group or an ether group, and the water solubility, the dissolving-out speed and the bioavailability are significantly improved. The Prunin derivative has better cough relieving and phlegm reducing effects, the curative effects on various coughs and asthma caused by acute bronchitis, chronic bronchitis, colds and the like are significant, and no toxic or side effect exists; compared with traditional cough medicine Nin Jiom Pei Pa Koa, the curative effect is more significant, and the Prunin derivative is an ideal drug for relieving the cough and reducing the phlegm, andhas a wide market prospect. The formula is defined in the description.
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Paragraph 0054; 0055
(2018/04/03)
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- Purification and characterization of an intracellular α-L-rhamnosidase from a newly isolated strain, Alternaria alternata SK37.001
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A strain, Alternaria alternata SK37.001, which produces an intracellular α-L-rhamnosidase, was newly isolated from citrus orchard soil. The molecular mass of the enzyme was 66 kDa, as evaluated by SDS-PAGE and 135 kDa, as determined by gel filtration, which indicated that the enzyme is a dimer. The enzyme had a specific activity of 21.7 U mg?1 after step-by-step purification. The optimal pH and temperature were 5.5 and 60 °C, respectively. The enzyme was relatively stable at a pH of 4.0–8.0 and a temperature between 30 and 50 °C compared with other pH levels and temperatures investigated. The enzyme activity was accelerated by Ba2+ and Al3+ but inhibited by Ni2+, Cu2+ and Co2+, especially Ni2+. The kinetic parameters of Km and Vmax were 4.84 mM and 53.1 μmol mg?1 min?1, respectively. The α-L-rhamnosidase could hydrolyze quercitrin, naringin and neohesperidin, hesperidin and rutin rhamnose-containing glycosides but could not hydrolyze ginsenoside Rg2 or saiko-saponin C.
- Zhang, Tao,Yuan, Wenbo,Li, Mengli,Miao, Ming,Mu, Wanmeng
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- Preparation method of flavone aglycone or monoglycoside from aluminum-salt-flavonoid-glycoside complex through hydrolysis
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Disclosed is a preparation method of flavone aglycone or monoglycoside from aluminum-salt-flavonoid-glycoside complex through hydrolysis. The problems that flavonoid glycosides neither dissolve in water nor are hard to dissolve in a common organic alcohol solution, and flavone aglycone prepared from hydrolysis has slow hydrolysis speed, needs a large amount of an organic solvent, and cannot be totally hydrolyzed are solved. A complex product from complexation of aluminum salt and flavonoid glycosides is easy to dissolve in alcohol, hydrogen chloride generated by the complex product is utilized with addition of hydrochloric acid or sulfuric acid, and hydrolysis is carried out at a certain temperature to prepare aglycone or a mixture of aglycone and monoglycoside. After the reaction is over, phosphoric acid or phosphate is added to break complexation of aluminum ions and flavone to obtain flavone aglycone, or the mixture of flavone aglycone and flavone monoglycoside, or a mixture of flavone aglycone, flavone monoglycoside, and flavonoid glycoside. The method is simple and easy to operate, relatively high in yield and purity, and extremely low in cost, and is suitable for massive industrial production of flavone aglycone or the mixture of flavone aglycone and flavone monoglycoside.
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Paragraph 0017
(2016/10/31)
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- α-Rhamnosidase activity in the marine isolate Novosphingobium sp. PP1Y and its use in the bioconversion of flavonoids
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Crude protein extracts of Novosphingobium sp. PP1Y, a microorganism isolated from polluted marine waters in Pozzuoli (Italy), were analyzed for the presence of glycosidase activities. Particular attention was devoted to a α-L-rhamnosidase activity able to hydrolyze several flavonoids of interest for the pharmaceutical and food industries. This activity had an alkaline pH optimum and a moderate tolerance to the presence of organic solvents, appealing features for its possible biotechnological uses. An increase of the α-L-rhamnosidase activity in PP1Y crude extracts was induced by adding naringin to the growth medium, suggesting the possibility to use material from Citrus industrial waste to induce the glycosidase activity expressed by strain PP1Y and produce simultaneously high-added-value molecules from the hydrolysis of their flavonoids. In order to investigate on the enzymatic mechanism of PP1Y α-L-rhamnosidase activity, hydrolysis products of PNP-α-L- rhamnopyranoside were analyzed by 1H-NMR experiments. The kinetic behaviour clearly indicated an inverting mechanism of hydrolysis for this novel enzymatic activity.
- Izzo, Viviana,Tedesco, Pietro,Notomista, Eugenio,Pagnotta, Eduardo,Di Donato, Alberto,Trincone, Antonio,Tramice, Annabella
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- Purification and characterization of a naringinase from Aspergillus aculeatus JMUdb058
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A naringinase from Aspergillus aculeatus JMUdb058 was purified, identified, and characterized. This naringinase had a molecular mass (MW) of 348 kDa and contained four subunits with MWs of 100, 95, 84, and 69 kDa. Mass spectrometric analysis revealed that the three larger subunits were β-d-glucosidases and that the smallest subunit was an α-l-rhamnosidase. The naringinase and its α-l-rhamnosidase and β-d-glucosidase subunits all had optimal activities at approximately pH 4 and 50 C, and they were stable between pH 3 and 6 and below 50 C. This naringinase was able to hydrolyze naringin, aesculin, and some other glycosides. The enzyme complex had a Km value of 0.11 mM and a kcat/Km ratio of 14 034 s-1 mM -1 for total naringinase. Its α-l-rhamnosidase and β-d-glucosidase subunits had Km values of 0.23 and 0.53 mM, respectively, and kcat/Km ratios of 14 146 and 7733 s -1 mM-1, respectively. These results provide in-depth insight into the structure of the naringinase complex and the hydrolyses of naringin and other glycosides.
- Chen, Yuelong,Ni, Hui,Chen, Feng,Cai, Huinong,Li, Lijun,Su, Wenjin
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p. 931 - 938
(2013/08/24)
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- Biotransformation of naringin and naringenin by cultured Eucalyptus perriniana cells
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The biotransformation of naringin and naringenin was investigated using cultured cells of Eucalyptus perriniana. Naringin (1) was converted into naringenin 7-O-β-d-glucopyranoside (2, 15%), naringenin (3, 1%), naringenin 5,7-O-β-d-diglucopyranoside (4, 15
- Shimoda, Kei,Kubota, Naoji,Taniuchi, Koji,Sato, Daisuke,Nakajima, Nobuyoshi,Hamada, Hatsuyuki,Hamada, Hiroki
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experimental part
p. 201 - 205
(2010/05/17)
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- Pressure-enhanced activity and stability of α-l-rhamnosidase and β-d-glucosidase activities expressed by naringinase
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Naringinase is an enzyme complex, expressing α-l-rhamnosidase and β-d-glucosidase activities. The impact of high pressure and temperature on naringinase activity and stability were studied, in order to assess the potential of enzyme thermostability on glycosides hydrolyses. To a better understanding of these effects on naringinase enzyme complex, they were also evaluated over α-l-rhamnosidase and β-d-glucosidase activities, using specific substrates, p-nitrophenyl α-l-rhamnopyranoside (4-NRham) and p-nitrophenyl β-d-glucopyranoside (4-NGluc), respectively. Hydrolysis rate of 4-NRham and naringin increased with pressure from 0.1 to 150 MPa. The equilibrium constants for α-l-rhamnosidase and β-d-glucosidase reactions, at pressures of 0.1-200 MPa and 40 °C, were determined and best fitted with the model of Baliga and Whalley equation. Accordingly, reaction volumes of 93 and 64 mL mol-1 were obtained for α-l-rhamnosidase and β-d-glucosidase reactions, respectively. Reaction rate constants were also determined at the same experimental conditions and well fitted to the models of Golinkin, Laidlaw, Hyne and of Burris and Laidler. A negative ΔV≠ of -7.7 ± 1.5 and -20.0 ± 5.2 mL mol-1 were obtained for α-l-rhamnosidase and naringinase reactions, correspondingly, which reflect the accelerating effect of pressure on the biocatalysis. Moreover, the KM, kcat and kcat/KM values, on naringin hydrolysis under atmospheric (0.1 MPa) and high pressure (150 MPa) conditions at different temperatures (25-80 °C) were determined. A 3-fold and 4-fold increase on naringinase thermostability was observed under 150 MPa at 70 and 80 °C, respectively, compared to 0.1 MPa experiments. In addition, a 15-fold increase of kcat/kM values from experimental conditions of 0.1 MPa and 30 °C to 150 MPa and 70 °C was observed. In fact, high pressure showed to be a powerful tool to increase stability of naringinase against thermal denaturation. In conclusion, the effect of amplification of pressure effects on reaction rates by temperature could have a pragmatic use for accelerating enzymatic reactions.
- Vila-Real, Helder,Alfaia, Antonio J.,Phillips, Robert S.,Calado, Antonio R.,Ribeiro, Maria H.L.
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experimental part
p. 102 - 109
(2011/02/16)
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- Improvement of activity and stability of soluble and sol-gel immobilized naringinase in co-solvent systems
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The hydrolysis of naringin, a bitter flavonone glycoside, with naringinase leads to reducing sugars (rhamnose and glucose), to prunin and to the aglycone, naringenin. To overcome the low solubility of naringin in the enzymatic reaction media, the effect of different solvents was studied, in order to improve the productivity and yield of the system. The effect of increasing concentration of co-solvents on the stability of both soluble and immobilized naringinase expressing α-l-rhamnosidase and β-d-glucosidase activities was evaluated. The enzyme was immobilized onto sol-gel matrices of tetramethoxysilane and glycerol. Combining the higher naringin solubility, and the higher residual activity of both α-l-rhamnosidase and β-d-glucosidase expressed by naringinase, eight solvents were chosen for stability and activity studies: dimethyl sulfoxide, N,N-dimethylmethanamide, methanol, ethanol, acetone, tetrahydrofurane, 1,2-dimethoxyethane and 1,4-dioxane. Deactivation of soluble naringinase was analyzed according to a first-order kinetic model. For the sol-gel immobilized enzyme the two-step deactivation model, of Henley and Sadana, was adjusted. Sol-gel immobilization stables naringinase in all tested co-solvents systems. This effect was specially pronounced at higher co-solvent concentration (10%). The half-life of α-l-rhamnosidase and β-d-glucosidase expressed by naringinase even increased 21- and 59-fold, respectively, in aqueous co-solvation with tetrahydrofurane. These are high innovative and sounding results showing the protective effect of immobilization onto sol-gel (tetramethoxysilane + glycerol) matrices with naringinase in co-solvent systems, which is a great advantage for non-conventional biocatalysis.
- Vila-Real, Helder,Alfaia, Antonio J.,Calado, Antonio R.,Ribeiro, Maria H.L.
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experimental part
p. 91 - 101
(2010/11/19)
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- Thermal inactivation and product inhibition of Aspergillus terreus CECT 2663 α-L-rhamnosidase and their role on hydrolysis of naringin solutions
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The kinetics of thermal inactivation of A. terreus α-rhamnosidase was studied using the substrate p-nitrophenyl α-L-rhamnoside between 50°C and 70°C. Up to 60°C the inactivation of the purified enzyme was completely reversible, but samples of crude or partially purified enzyme showed partial reversibility. The presence of the product rhamnose, the substrate naringin, and other additives reduced the reversible inactivation, maintaining in some cases full enzyme activity at 60°C. A mechanism for the inactivation process, which permitted the reproduction of experimental results, was proposed. The products rhamnose (inhibition constant, 2.1 mM) and prunin (2.6 mM) competitively inhibited the enzyme reaction. The maximum hydrolysis of supersaturated naringin solution, without enzyme inactivation, was observed at 60°C. Hydrolysis of naringin reached 99% with 1% naringin solution, although the hydrolysis degree of naringin was only 40% due to products inhibition when the initial concentration of flavonoid was 10%. The experimental results fitted an equation based on the integrated Michaelis-Menten's, including competitive inhibition by products satisfactorily.
- Soria, Fernando,Ellenrieder, Guillermo
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p. 1442 - 1449
(2007/10/03)
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- ACYLATED FLAVANONE GLYCOSIDES FROM Ricinus communis
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Naringenin 7-O-(6''-O-p-coumaroyl-β-D-glucopyranoside) and new the flavanone naringenin 7-O-(2''-O-p-coumaroyl-β-D-glucopyranoside) have been isolated from the seeds of Ricinus communis L.The structures of the compounds isolated were established on the basis of the results of chemical transformations and spectral characteristics.
- Yuldashev, M. P.,Batirov, E. Kh.,Malikov, V. M.,Yuldashev, P. Kh.
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p. 303 - 305
(2007/10/02)
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- GLUCOSYLATION OF EXOGENOUS FLAVANONES BY GRAPEFRUIT (CITRUS PARADISI) CELL CULTURES
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Key Word Index - Citrus paradisi; Rutaceae; grapefruit; biotransformation; glucosylation; plant cell cultures; flavanones; flavanone glycosides; prunin; hesperitin 7-O-glucoside; 1H NMR.Grapefruit (Citrus paradisi) cells in suspension cultures did not accumulate flavanone glycosides but were able to specifically O-glucosylate exogenous naringenin and hesperitin at position 7.The products were extracted from the cultures using a new technique: absorption on an Amberlite XAD-2 resin and further purification by BioGel-P4 column chromatography.The flavanone glycosides obtained were analyzed by high-resolution 1H NMR and the spectra compared to authentic flavanone aglycones, mono- and diglycosides.
- Lewinsohn, Efraim,Berman, Elisha,Mazur, Yehuda,Gressel, Jonathan
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p. 2531 - 2536
(2007/10/02)
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