Improvement effect of arbutin on myocardial fibrosis model rats and its mechanism / 中国药房

OBJECTIVE To study the improvement effects of arbutin on myocardial fibrosis （MF） model rats and its mechanism. METHODS The network pharmacology was used to predict the potential target of arbutin in improving MF and molecular docking was used to validated. Totally 50 SD rats were given isoprenaline subcutaneously （5 mg/kg， once a day， for 14 consecutive days） to induce the MF model. Modeled rats were randomly divided into model group， captopril group （9 mg/kg）， arbutin low-dose， medium-dose and high-dose groups （50， 100， 200 mg/kg）， with 10 rats in each group. Another 10 healthy rats were included as normal group. Each group was given the corresponding drugs， once a day， for 28 consecutive days. Twenty-four hours after the final administration， electrocardiograms and heart-related indexes [heart weight index （HWI）， left ventricular weight index （LVWI）] of rats were detected； the levels of creatine kinase （CK）， lactate dehydrogenase （LDH）， N-terminal pro-brain natriuretic peptide （NT-proBNP） and type Ⅰ collagen （Col Ⅰ） and Col Ⅲ were detected in myocardial tissue of rats； the pathological changes of myocardial tissue were observed， and protein and mRNA expressions of adenosine deaminase （ADA） and adenosine kinase （ADK） were detected in the myocardial tissue of rats. RESULTS The results of network pharmacology showed that the main targets of arbutin improving MF were ADA and ADK. The results of molecular docking showed that arbutin bind stably with ADA and ADK. The results of experimental verification showed that compared with model group， the amplitude of ST and T waves in electrocardiogram were improved in administration groups， and the symptoms of atrial flutter were alleviated； HWI （except for arbutin medium-dose group）， LVWI， the levels of CK， LDH， NT-proBNP， Col Ⅰ and Col Ⅲ in the myocardial tissue of rats were decreased significantly （P＜0.05）； the degree of myocardial fibrosis in rats decreased； protein and mRNA expressions of ADA and ADK in the myocardial tissue were significantly increased （P＜0.05）. CONCLUSIONS Arbutin can improve cardiac fibrosis and cardiac function of MF model rats， the mechanism of which may be associated with up-regulating protein and mRNA expressions of ADA and ADK，influencing the nucleotide metabolism and collagen generation. zhangminghao@hactcm.edu.cn

Protective effect and mechanism of arbutin on cisplatin-induced renal tubular epithelial cell injury / 中华肾脏病杂志

The aim of this study was to elucidate the protective effect of arbutin on cisplatin (Cis) induced renal tubular epithelial cell injury and its mechanism. Cell counting kit-8 was used to detect the viability of renal tubular epithelial cells. The toxicity of arbutin on renal tubular epithelial cells at different concentrations and the appropriate concentration of arbutin to protect cells against cisplatin were observed. The renal tubular epithelial cells were divided into control group, arbutin group, Cis group and arbutin+Cis group. Flow cytometry, quantitative real-time PCR and Western blotting were used to detect the levels of apoptosis and inflammation. The results showed that arbutin had no significant toxic effect on renal tubular epithelial cells in the mentioned concentration range (0-200 μmol/L). When the concentration of arbutin exceeded 100 μmol/L, it showed a protective effect on renal tubular epithelial cells. Arbutin intervention significantly reduced cisplatin-induced apoptosis of renal tubular epithelial cells and the increase of inflammation-related molecules p-p65 and interleukin-18. In addition, arbutin intervention reversed the cisplatin-induced reduction of Bcl-2 in renal tubular epithelial cells. These findings suggest that arbutin can attenuate cisplatin-induced renal tubular epithelial cell injury through anti-apoptotic and anti-inflammatory responses, which may be expected to be a new potential therapeutic drug for acute kidney injury.

Arbutin isolated from Chinese yam inhibits LPS-induced NRK-52e cell apoptosis by ERp / 中国药理学通报

Aim To investigate the effect of arbutin on apoptosis of NRK-52e cells induced by LPS and the potential mechanism.Methods The model of NRK- 52e cells injury was constructed by LPS, and NRK-52e cells were divided into control, LPS ( 1 mg • L 1 ) , low dose arbutin (LPS, 1 mg • L 1 + arbutin, 5 (xmol • L_l ) , high dose arbutin ( LPS, 1 mg • L 1 + arbutin , 10 (xmol • L 1 ) and its corresponding inhibitor THC group ( 1 (xmol • L 1).The cell viability was detected ; the levels of ROS, apoptosis, Ca~' concentration and mitochondrial membrane potential ( MMP ) were detected by flow cytometry; the levels of key apoptosis proteins were detected by in cell western; the binding activity of arbutin with ER(3 was imitated by molecular docking technology, and verified by in cell western.Results Arbutin could effectively regulate the levels of ROS, Ca"+ , apoptosis proteins and ER(3 in NRK-52e cells induced by LPS and inhibit the de- cline of MMP, which is blocked by estrogen receptor inhibitor THC.In addition, arbutin has good binding activity with ERf}.Conclusion This study confirms that arbutin could inhibit LPS-induced apoptosis of NRK-52e cells through ER£.

Characterization of a sucrose phosphorylase from Leuconostoc mesenterides for the synthesis of α-arbutin / 生物工程学报

Sucrose phosphorylase (SPase) gene from Leuconostoc mesenteroides ATCC 12291 was synthesised after codon optimization, and inserted into pET-28a plasmid to generate pET-28a-spase. The recombinant strain Escherichia coli BL21 (DE3)/pET-28a-spase was induced for Spase expression. The recombinant protein Spase was purified and characterized. The specific enzyme activity of SPase was 213.98 U/mg, the purification ratio was 1.47-fold, and the enzyme activity recovery rate was 87.80%. The optimal temperature and the optimal pH of the SPase were identified to be 45 °C and 6.5 respectively, and Km, Vmax and kcat of the SPase for sucrose was 128.8 mmol/L, 2.167 μmol/(mL·min), and 39 237.86 min-1. The recombinant SPase was used for α-arbutin production from hydroquinone and the reaction process was evaluated. The optimal conditions for synthesis of α-arbutin by SPase were 40 g/L hydroquinone, 5:1 molar ratio of sucrose and hydroquinone, and 250 U/mL recombinant SPase at pH 7.0 and 30 °C for 24 h in the dark, and then 500 U/mL glucoamylase was added at 40°C for 2.5 h. Under the optimized process, the yield of α-arbutin reached 98 g/L, and the hydroquinone conversion rate was close to 99%. In summary, the recombinant SPase was cloned and characterized, and its application for α-arbutin production was feasible.

Preparation, characterization and physicochemical properties of arbutin phospholipid complex / 中草药

Objectives To prepare arbutin phospholipid complex (APC) to improve the skin permeability of arbutin and discuss the formation mechanism of APC. Methods Solvent evaporation method was used to prepare APC. The formation of APC was confirmed by differential scanning calorimetry (DSC), X-ray diffraction (XRD), infrared spectroscopy (IR), 1H nuclear magnetic resonance (1H-NMR), scanning electron microscopy (SEM) and transmission electron microscope (TEM). The solubility, skin permeability and the ability to inhibit tyrosinase of APC were evaluated. Results The analysis showed that the weak interaction between phospholipid and arbutin molecules formed APC. The solubility of arbutin in APC in n-octanol increased from 1.29 µg/mL to 9.54 µg/mL, and the formation of APC effectively increased the lipophilicity of arbutinn. In vitro release study demonstrated that APC exhibited sustained release behavior. Ex vitro penetration studies showed that arbutin was difficult to reach the subcutaneous tissue through the skin, but APC showed strong penetration ability, of which permeation flux was improved from 0.02 mg/cm2 to 0.42 mg/cm2. Enzyme inhibitory activity test showed that the inhibition of APC on tyrosinase activity was 1.85 times of arbutin. Conclusions The formation of the complex improved the bioavailability of arbutin, and the complex held higher application potential for medicinal and cosmetic.

Determination of six polyphenols in different parts of Queshe tea extracted by different processes by HPLC / 中草药

Objective: To establish HPLC method for the determination of 6'-O-caffeoylarbutin (1), arbutin (2), robustaside A (3), p-hydroxybenzoic acid (4), caffeic acid (5) and caffeic acid methyl ester (6) of Queshe tea. Methods: Using the SunFire® C18 (250 mm×4.6 mm, 5 μm) chromatographic column, mobile phase of acetonitrile-0.1% phosphoric acid aqueous solution, the flow rate at 1.0 mL/min, and column temperature at 30 ℃ to optimum the extraction method of Queshe tea and investigate the linearity, stability and repeatability of the method. Results: With distilled water as the extraction solvent, the highest extraction rate can be obtained by ultrasonic extraction for 20 min. Under the above chromatographic conditions, 6'-O-caffeoylarbutin (1), arbutin (2), robustaside A (3), p-hydroxybenzoic acid (4), caffeic acid (5) and caffeic acid methyl ester (6) have good separation effect, and the experiment has good linearity, stability and repeatability. Conclusion: The method is simple, sensitive and accurate, and can be used for the detection of the above six main chemical components.

New arbutin derivatives from the leaves of Heliciopsis lobata with cytotoxicity / 中国天然药物

Heliciopsis lobata is a medicinal plant, which is exclusively used to treat tumor in Li folk region. Two new arbutin derivatives, 6'-((E)2-methoxy-5-hydroxycinnamoyl) arbutin (1) and 2'-((E)2, 5-dihydroxycinnamoyl) arbutin (2) along with five known compounds (3-7), were isolated from the leaves of Heliciopsis lobata. Their structures were elucidated on the basis of extensive spectroscopic interpretations. They were evaluated for their potential anticancer activity. Compounds 6 and 7 exhibited cytotoxicity against MGC-803 cells with IC values being 44.1 and 11.3 μg·mL, respectively. Additionally, compounds 1, 2 and 5-7 exhibited a moderate inhibition of MGC-803 cells invasion; compound 2 at 20 μg·mL inhibited the invasion of MGC-803 cells by 43.0%, compared with the controls.

Response to intradermal autologous platelet rich plasma injection in refractory dermal melasma: report of two cases

Refractory dermal melasma is resistant to conventional treatment. Platelet rich plasma (PRP) may help to reduce the pigmentation of melasma. We present a case report on the clinical outcome of 2 patients with melasma, given PRP, as an adjunct therapy. PRP was administered at a monthly interval for 2 sessions in combination with a monthly Q-switched Nd Yag laser treatment and topical alpha arbutin application. A modified melasma area and severity index (MASI) was evaluated by two dermatologists who were blinded. At the follow up on the 3rd months, the MASI score was reduced by mean 33.5% for case 1 and 20% for case 2. There were no clinical complications for case 1. However recurrence of melasma was noted in case 2 by a worsening of the MASI score mean to 53% at the sixth months follow up. In conclusion, intradermal PRP injection as an adjunct to the conventional treatment of melasma presented with differing results in two cases.

Activity of the hydroquinone its based TLC/HPLC analysis / Монголын Анагаах Ухаан

BackgroundHydroquinone (1,4 di-hydroxy benzene) is an aromatic organic compound with diverse biologicalfunctions that are commonly used as pigment or cosmetic additives. Its chemical structure has twohydroxyl groups bonded to a benzene ring in a para position. In the nature hydroquinone have a primaryreagent in the defensive glands of bombardier beetles, along with hydrogen peroxide, which collects in areservoir [1]. Hydroquinone glycoside form is 4-hydroxyphenyl-α-D-glucopyranoside (α- Arbutin). Arbutinis a potent inhibitor of melanin synthesis and has been reported to possess inhibitory activity on lipidperoxidation and is used in the cosmetic industry for its antibacterial and skin lightening effects [9]. It isfaster and more effictive another commonly used skin lightener, even at use very low concentrations.Material and MethodsThe in vitro glycosylation reaction was carried out as described in materials and methods. DNA wasextracted than E.coli BL 21 and E.coli JM 109 hosts were used for expression of proteins. The purifiedprotein was then analyzed by 12% SDS-PAGE than used for enzymatic recycle system. Hydroquinonereaction mixture was incubated at 37ºC for 8 and 24 hour than quenched by heating in boiling waterfor 10 min. The reactions products was first analyzed by TLC followed by HPLC analysis.ResultsThis work substrate hydroquinone for the enhancement of enzymatic recycling system glycosylation. TLCand HPLC analyses of the products were carried out to the recycled system worked and glycosylationproduct.ConclusionIn this study, hydroxyl groups of the para position of hydroquinone involved for glycosylation to comparewith standards were analysed by TLC and HPLC. When the compared 8 hour reactions obtained theapparent glycosylation and stability of the recycling system.

Simultaneous determination of nine compounds in Bergenia purpurascens by HPLC-MS / 中国药学杂志

OBJECTIVE: To develop a method for the determination of arbutin, gallic acid, bergenin, protocatechuic acid, chlorogenic acid, catechin, epicatechin, epicatechin gallate, and ferulic acid in Bergenia purpurascens by HPLC-MS/MS. METHODS: The samples were separated on a Diamonsil C18 column (4.6 mm × 150 mm, 5 μm) by gradient elution using methanol and 0.2‰(V/V) formic acid aqueous solution as the mobile phase at a flow rate of 0.8 mL · min-1. The column temperature was room temperature. Multiple-reaction monitoring (MRM) scanning was employed for quantification with switching electrospray ion source polarity in negative mode. RESULTS: Complete separation was achieved within 10 min for the nine compounds (arbutin, gallic acid, bergenin, protocatechuic acid, chlorogenic acid, catechin, epicatechin, epicatechin gallate, ferulic acid): The nine regression equations showed linear relationships between peak areas and contents of each compound. The average recoveries (n=9) of the compounds listed above were 100.2%, 100.0%, 99.8%, 99.9%, 97.9%, 101.2%, 99.8%, 101.7%, 102.4% and RSD were 0.80%, 3.06%, 2.72%, 3.28%, 3.58%, 1.44%, 0.95%, 0.96%, 0.48%, respectively. CONCLUSION: The method is simple, accurate and has good reproducibility, thus can be used for the determination of the nine compounds in Bergenia purpurascens.

Estudo clínico para a avaliação das propriedades clareadoras da associação de ácido kójico, arbutin, sepiwhite® e achromaxyl® na abordagem do melasma, comparada à hidroquinona 2% e 4% / Evaluation of the whitening properties of combined kojic acid, arbutin, sepiwhite® and achromaxyl® vs. 2% and 4% hydro- quinone in the treatment of melasma

Introdução: Melasma é alteração cutânea comum e adquirida, de curso prolongado e tratamento muitas vezes refratário, gerando impacto psicológico negativo na vida dos acometidos. Objetivos: Avaliar a eficácia, segurança e tolerabilidade da combinação tópica de ácido kójico, arbutin, sepiwhite® e achromaxyl ® em comparação à hidroquinona a 2% e a 4% na abordagem do melasma facial. Métodos: Estudo clínico mono-cego, comparativo, monocêntrico, com 120 voluntárias, fototipos I a IV de Fitzpatrick, entre 18 e 50 anos de idade, divididas em grupo A (n = 40; Blancy® 2 vezes ao dia), grupo B (n = 40; hidroquinona 2% à noite) e grupo C (n = 40; hidroquinona 4% à noite), que usaram os produtos durante 90 dias consecutivos. Foram realizadas avaliações clínicas (classificação e quantificação do melasma) e fotográficas, além do questionário de impacto à qualidade de vida e avaliação global deeficácia. Resultados: Cento e duas voluntárias (85%) finalizaram o estudo, (grupo A = 34, grupo B = 33, grupo C = 35). A métrica do Masi teve redução estatisticamente significante ao longo do estudo para os três Grupos (p-valor < 0,001). Conclusão: O uso tópico da associação de ácido kójico, arbutin, sepiwhite® e achromaxyl ® demonstrou ser eficaz e seguro na abordagem do melasma, apresentando-se como alternativa no arsenal terapêutico dessa dermatose recalcitrante e inestética.

Introduction: Melasma is a common, acquired, long-lasting skin disorder that is often resistant to treatment and causes negative psychological effects on patients. Objectives: To evaluate the efficacy, safety, and tolerability of the topical combination of kojic acid, arbutin, sepiwhite® and achromaxyl ® compared to 2% and 4% hydroquinone in the treatment of facial melasma. Methods: A single-blind, comparative, monocentric clinical study with 120 volunteers (aged 18-50, I to IV Fitzpatrick skin types) was conducted. The study population was divided into 3 groups: Group A (n = 40; Blancy®, 2 times a day), Group B (n = 40, 2% hydroquinone at night), and Group C (n = 40, 4% hydroquinone at night), and instructed to use the study product for 90 consecutive days. Clinical (classification and quantification of melasma) and photographic evaluations were carried out, and a questionnaire assessed the impact on the patients' quality of life and the products' general efficacy. Results: Most volunteers (n = 102, 85%) completed the study (Group A = 34, Group B = 33, Group C = 35). The Melasma Area Severity Index metrics presented a statistically significant decrease (i.e., improvement) throughout the study in all three groups (p-value < 0.001). Conclusion: The topical use of the kojic acid, arbutin, sepiwhite® and achromaxyl® combination proved to be an effective and safe alternative for treating melasma.

Microneedle technique in promoting transdermal delivery of arbutin / 第二军医大学学报

Objective: To study the promoting effects of microneedle arrays on transdermal delivery of arbutin by comparing with the effect of chemical penetration enhancer azone. Methods: The microneedles were fabricated with single-crystal Si as starting material using a series of photolithography, thin-film deposition, and reactive ion etching techniques. Franz-cells were used in the transdermal delivery experiment with human abdominal skin. The study was divided into the following 3 groups; the microneedle group (arbutin hydrogel without penetration enhancer, and the skin was treated with microneedle arrays) ; the control group (arbutin hydrogels containing 1% , 3% , and 5% azone (W/V) , and the skin received no microneedle treatment); and blank control group (arbutin hydrogel without azone, and the skin received no microneedle treatment). Arbutin levels in the receptor solution, epidermis and dermis were determined by HPLC at 1, 3 , 6 , 12, 24, 36 and 48 h. The analyses were performed with a C18 column (250 mm X 4.6 mm, 5μm), at room temperature, mobile phase methanol : 1×10-3 mol/ml HCl solution (V/V, 5 : 95), flow rate 1 ml/min, and detective wavelength 282 nm. The accumulative penetration amount (Qr), steady-state flux (J s) and the accumulative deposition amount (Qs) were calculated. Results: The microneedles could pass the human skin. The standard curve was; C=0.000 2A=0.182 9 (r=0.999 9) , 0.4-50 μg/ml. The RSD values of intraday and interday precisions were 2.4% and 2.74%, respectively; and the recovery was higher than 90%. The values of Qr, Js, and Qs in the microneedle group were significantly higher than those in the 5% azone group (P<0.01). Conclusion: Microneedles can greatly promote the skin permeability and deposition of arbutin.

A New Cyano-compound from Rhodiola kirilowii / 中草药·英文版

Objective To study the chemical constituents of Rhodiola kirilowii.Methods The compounds were separated and purified by various chromatographic techniques and their structures were elucidated on the basis of physicochemical properties and spectroscopic methods.Results Five compounds were purified and their structures were identified as 4-(β-D-glucopyranosyloxy)-3-hydroxy-2-(hydroxymethyl)-butanenitrfle (1),epicatechin (2),arbutin (3),rutin (4),and β-D-glucose (5).Conclusion Compound 1 is a new cyano-compound and other compounds are isolated from the plant for the first time.

Efficacy of Hydrogel Mask with 2% Arbutin for Melasma / 대한피부과학회지

BACKGROUND: Melasma is a common, acquired, symmetrical hypermelanosis that occurs on sun exposed areas of the skin. It is more prevalent among Asian women than among Caucasian women. Many different treatment modalities have been used with various efficacies, but none of them have been completely satisfactory. Arbutin is a naturally occurring gluconopyranoside that may reduce tyrosinase activity, which is a rate-limiting enzyme for melanin production. OBJECTIVE: The purpose of this study was to investigate the depigmenting effect and safety of a mask that contains 2% arbutin for the treatment of melasma. METHODS: A total of 54 female volunteers with melasma were enrolled in this randomized, double-blind, 8-week treatment study. The patients were instructed to apply an arbutin-containing mask or an arbutin-free mask once a day for 8 weeks. The assessment of outcomes included the Melasma Area and Severity Index (MASI) score, colorimetric value (L*), overall patient satisfaction and investigator assessment score (evaluated using photography). RESULTS: The arbutin-containing mask significantly increased the right and left colorimetric values (L*) after the 8-week treatment (p0.05). The arbutin mask scored better than the control in patient satisfaction and investigator assessment. No significant adverse reactions were observed. CONCLUSION: The arbutin mask appears to be effective and well-tolerated when used for the treatment of melasma.

Therapeutic Effect of Arbutin Combined with Glycyrrhizin on Immune-inflammation / 中国中医药信息杂志

Objective To study the therapeutic effect of arbutin combined with glycyrrhizin on immune-inflammation. Methods The effect of arbutin combined with glycyrrhizin on adjuvant arthritis and on oxzolone induced mice ear swelling were investigated. PGE2 level in inflammatory tissue and LTB4 content from peritoneal macrophage of rat treated with arbutin and glycyrrhizin were determined. Results Arbutin combined with glycyrrhizin could inhibit Freund's complete adjuvant induced rat primary and secondary foot swelling. The combined group could also inhibit oxazolone induced mice ear swelling and decrease CD4+ T cell in blood. Compared with control group,PGE2 level in combined group was remarkable lower,and there was no difference between combined group and GL 400 mg/kg group. Arbutin combined with glycyrrhizin could inhibit LTB4 release from rat peritoneal macrophage. Conclusion Arbutin and glycyrrhizin has synergetic therapeutic effect on immune-inflammation.

Antimelanogenic effects of Arbutin / 대한피부과학회지

BACKGROUND: Arbutin is a glycosylated hydroquinone found at high concentration in certain plants capable of surviving extreme and sustained dehydration. It has been suggested as an inhibitory compound of melanogenesis. OBJECTIVE: The purpose of this study was to investigate the effect of arbutin on melanogenesis in cultured human melanocytes and to evaluate the effectiveness of arbutin in patients with melasma. METHODS: I. In vitro study:we examine the cell number, SRB assay, tyrosinase activity, and melanin contents of cultured human melanocytes in control(absence of arbutin) and experimental groups (presence of 10(-5) M, 10(-4) M, and 10(-3) M arbutin). II. In vivo study:6 patients with melasma applied a 3 % arbutin solution twice daily for 8 weeks. Clinical response to treatment was evaluated by patients' subjective assessment and MASI(Melasma Area and Severity Index) score after 8 weeks of treatment. RESULTS: I. In vitro study 1. The number of melanocytes was decreased in groups treated with 10(-5) M, 10(-4) M, 10(-3) M arbutin for 2 days and 10(-4) M, 10(-3) M arbutin for 7 days. 2. On SRB assay, the proliferation of melanocytes was decreased in groups treated with 10(-5) M, 10(-4) M, 10(-3) M arbutin for 2 days and for 7 days. 3. Tyrosinase activity was decreased in groups treated wtih 10(-4) M, 10(-3) M arbutin for 2 days and 10(-5) M, 10(-4) M, 10(-3) M arbutin for 7 days. 4. The melanin contents were decreased in group treated with 10(-3) M arbutin for 7 days. II. In vivo study 1. On patients'subjective assessment, one showed moderate improvement, one showed mild improvement, and the other four showed no change. 2. On MASI score, there was less than 10% improvement in all 6 patients. 3. Side effects were not found in all 6 patients. CONCLUSION: Although arbutin showed an inhibitory effect on cell proliferation, tyrosinase activity, and melanin synthesis in cultured human melanocytes, there was no significant effect of depigmentation in the patients with melasma.

Biosynthesis of arbutin from crown gall of transgenic Panax quinquefolium / 中草药

Objective To investigate the biosynthesis of arbutin by suspension culture of crown gall of transgenic Panax quinquefolium. Methods Hydroquinone in methanol(60 mg/mL) was added to the medium of the crown gall of P.quinquefolium after precultured for 20 d,then they were co-cultured for another 60 h.The product was isolated and purified by column chromatography and its structure was identified by physicochemical properties and spectroscopic data.The dynamic curve of biotransformation was investigated by quantative analysis of arbutin with HPLC.Results The product could be obtained from both of the culture and medium,which was isolated and elucidated as 4-hydroxyphenyl-?-D-glucopyranoside(arbutin).After co-cultured for 60 h,the mole conversion ratio of hydroquinone is 88.4%,the product contents in culture and medium are 63.69 mg/flask and 1.86 mg/flask,respectively,and the excretion ratio of arbutin reaches the highest(2.92%).Conclusion It's the first time around the world that the crown gall of transgenic P.quinquefolium is used as a biotransformation system and arbutin which shows varied pharmacological activites have been got successfully.

The Biosynthesis of ?-arbutin by Xanthomona maltophilia BT-112 / 微生物学通报

?-arbutin is biosynthesized by whole cell method with Xanthomona maltophilia BT-112.The conditions for cell biosynthesized ?-arbutin are investigated as follows:temperature,25℃;concentration of hydroquinone,30mmol/L;mol ratio of sucrose and hydroquinone,20∶1;time course of ?-arbutin biosynthesis,45 hours;rotational speed,160r/min;concentration of Xanthomona maltophilia BT-112,85g/L;concentration of K-2HPO-4-KH-2PO-4 buffer solution,25mmol/L;pH of K-2HPO-4-KH-2PO-4 buffer solution,8.0.Under the above optimal conditions,the maximum of molar conversion yield based on the amount of hydroquinone supplied reaches 86.7%.