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1.
Molecules ; 27(13)2022 Jun 24.
Artigo em Inglês | MEDLINE | ID: mdl-35807322

RESUMO

Puerarin (daidzein-8-C-glucoside) is an isoflavone isolated from several leguminous plants of the genus Pueraria. Puerarin possesses several pharmacological properties; however, the poor solubility of puerarin limits its applications. To resolve this poor solubility, Deinococcus geothermalis amylosucrase (DgAS) was used to modify puerarin into more soluble derivatives. The results showed that DgAS could biotransform puerarin into a novel compound: puerarin-4'-O-α-glucoside. The biotransformation reaction was manipulated at different temperatures, pH values, sucrose concentrations, reaction times, and enzyme concentrations. The results showed that the optimal reaction condition was biotransformed by 200 µg/mL DgAS with 20% (w/v) sucrose at pH 6 and incubated at 40 °C for 48 h, and the optimal production yield was 35.1%. Puerarin-4'-O-α-glucoside showed 129-fold higher solubility than that of puerarin and, thus, could be further applied for pharmacological use in the future.


Assuntos
Glucosídeos , Isoflavonas , Proteínas de Bactérias/metabolismo , Deinococcus , Glucosídeos/química , Glucosiltransferases , Isoflavonas/química , Sacarose/metabolismo
2.
Biosci Biotechnol Biochem ; 85(3): 687-690, 2021 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-33580686

RESUMO

Ganoderic acid A (GAA) is a lanostane-type triterpenoid, isolated from medicinal fungus Ganoderma lucidum, and possesses multiple bioactivities. In the present study, GAA was sequentially biotransformed by 2 recently discovered Bacillus glycosyltransferases (GT), BtGT_16345 and BsGT110, and the final product was purified and identified as a new compound, GAA-15,26-O-ß-diglucoside, which showed 1024-fold aqueous solubility than GAA.


Assuntos
Bacillus/enzimologia , Dissacarídeos/biossíntese , Glicosiltransferases/metabolismo , Ácidos Heptanoicos/metabolismo , Lanosterol/análogos & derivados , Saponinas/biossíntese , Triterpenos/metabolismo , Cromatografia Líquida de Alta Pressão , Glicosilação , Lanosterol/metabolismo , Reishi/metabolismo , Solubilidade
3.
Int J Mol Sci ; 22(18)2021 Sep 09.
Artigo em Inglês | MEDLINE | ID: mdl-34575908

RESUMO

Ganoderma lucidum is a medicinal fungus abundant in triterpenoids, its primary bioactive components. Although numerous Ganoderma triterpenoids have already been identified, rare Ganoderma triterpenoid saponins were recently discovered. To create novel Ganoderma saponins, ganoderic acid G (GAG) was selected for biotransformation using four Bacillus glycosyltransferases (GTs) including BtGT_16345 from the Bacillus thuringiensis GA A07 strain and three GTs (BsGT110, BsUGT398, and BsUGT489) from the Bacillus subtilis ATCC 6633 strain. The results showed that BsUGT489 catalyzed the glycosylation of GAG to GAG-3-o-ß-glucoside, while BsGT110 catalyzed the glycosylation of GAG to GAG-26-o-ß-glucoside, which showed 54-fold and 97-fold greater aqueous solubility than that of GAG, respectively. To our knowledge, these two GAG saponins are new compounds. The glycosylation specificity of the four Bacillus GTs highlights the possibility of novel Ganoderma triterpenoid saponin production in the future.


Assuntos
Bacillus/metabolismo , Glicosiltransferases/metabolismo , Triterpenos/metabolismo , Proteínas de Bactérias , Biotransformação , Catálise , Cromatografia Líquida de Alta Pressão , Glicosilação , Estrutura Molecular , Solubilidade , Triterpenos/química
4.
Molecules ; 26(20)2021 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-34684855

RESUMO

Vitexin is a C-glucoside flavone that exhibits a wide range of pharmaceutical activities. However, the poor solubility of vitexin limits its applications. To resolve this limitation, two glycoside hydrolases (GHs) and four glycosyltransferases (GTs) were assayed for glycosylation activity toward vitexin. The results showed that BtGT_16345 from the Bacillus thuringiensis GA A07 strain possessed the highest glycosylation activity, catalyzing the conversion of vitexin into new compounds, vitexin-4'-O-ß-glucoside (1) and vitexin-5-O-ß-glucoside (2), which showed greater aqueous solubility than vitexin. To our knowledge, this is the first report of vitexin glycosylation. Based on the multiple bioactivities of vitexin, the two highly soluble vitexin derivatives might have high potential for pharmacological usage in the future.


Assuntos
Apigenina/metabolismo , Glucosídeos/metabolismo , Bacillus thuringiensis/metabolismo , Catálise , Flavonas/metabolismo , Glicosilação , Glicosiltransferases/metabolismo , Isoflavonas/metabolismo , Solubilidade
5.
Int J Mol Sci ; 20(20)2019 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-31635144

RESUMO

Strain GA A07 was identified as an intestinal Bacillus bacterium of zebrafish, which has high efficiency to biotransform the triterpenoid, ganoderic acid A (GAA), into GAA-15-O-ß-glucoside. To date, only two known enzymes (BsUGT398 and BsUGT489) of Bacillus subtilis ATCC 6633 strain can biotransform GAA. It is thus worthwhile to identify the responsible genes of strain GA A07 by whole genome sequencing. A complete genome of strain GA A07 was successfully assembled. A phylogenomic analysis revealed the species of the GA A07 strain to be Bacillus thuringiensis. Forty glycosyltransferase (GT) family genes were identified from the complete genome, among which three genes (FQZ25_16345, FQZ25_19840, and FQZ25_19010) were closely related to BsUGT398 and BsUGT489. Two of the three candidate genes, FQZ25_16345 and FQZ25_19010, were successfully cloned and expressed in a soluble form in Escherichia coli, and the corresponding proteins, BtGT_16345 and BtGT_19010, were purified for a biotransformation activity assay. An ultra-performance liquid chromatographic analysis further confirmed that only the purified BtGT_16345 had the key biotransformation activity of catalyzing GAA into GAA-15-O-ß-glucoside. The suitable conditions for this enzyme activity were pH 7.5, 10 mM of magnesium ions, and 30 °C. In addition, BtGT_16345 showed glycosylation activity toward seven flavonoids (apigenein, quercetein, naringenein, resveratrol, genistein, daidzein, and 8-hydroxydaidzein) and two triterpenoids (GAA and antcin K). A kinetic study showed that the catalytic efficiency (kcat/KM) of BtGT_16345 was not significantly different compared with either BsUGT398 or BsUGT489. In short, this study identified BtGT_16345 from B. thuringiensis GA A07 is the catalytic enzyme responsible for the 15-O-glycosylation of GAA and it was also regioselective toward triterpenoid substrates.


Assuntos
Bacillus thuringiensis/enzimologia , Proteínas de Bactérias/metabolismo , Genoma Bacteriano , Glicosiltransferases/metabolismo , Ácidos Heptanoicos/química , Ácidos Heptanoicos/metabolismo , Lanosterol/análogos & derivados , Bacillus thuringiensis/genética , Proteínas de Bactérias/genética , Biotransformação , Catálise , Glicosilação , Glicosiltransferases/genética , Lanosterol/química , Lanosterol/metabolismo , Filogenia , Especificidade por Substrato , Sequenciamento Completo do Genoma
6.
Molecules ; 24(12)2019 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-31208027

RESUMO

8-Hydroxydaidzein (8-OHDe), an ortho-hydroxylation derivative of soy isoflavone daidzein isolated from some fermented soybean foods, has been demonstrated to possess potent anti-inflammatory activity. However, the isoflavone aglycone is poorly soluble and unstable in alkaline solutions. To improve the aqueous solubility and stability of the functional isoflavone, 8-OHDe was glucosylated with recombinant amylosucrase of Deinococcus geothermalis (DgAS) with industrial sucrose, instead of expensive uridine diphosphate-glucose (UDP-glucose). One major product was produced from the biotransformation, and identified as 8-OHDe-7-α-glucoside, based on mass and nuclear magnetic resonance spectral analyses. The aqueous solubility and stability of the isoflavone glucoside were determined, and the results showed that the isoflavone glucoside was almost 4-fold more soluble and more than six-fold higher alkaline-stable than 8-OHDe. In addition, the anti-inflammatory activity of 8-OHDe-7-α-glucoside was also determined by the inhibition of lipopolysaccharide-induced nitric oxide production in RAW 264.7 cells. The results showed that 8-OHDe-7-α-glucoside exhibited significant and dose-dependent inhibition on the production of nitric oxide, with an IC50 value of 173.2 µM, which remained 20% of the anti-inflammatory activity of 8-OHDe. In conclusion, the well-soluble and alkaline-stable 8-OHDe-7-α-glucoside produced by recombinant DgAS with a cheap substrate, sucrose, as a sugar donor retains moderate anti-inflammatory activity, and could be used in industrial applications in the future.


Assuntos
Anti-Inflamatórios/metabolismo , Deinococcus/genética , Deinococcus/metabolismo , Glucosídeos/biossíntese , Glucosiltransferases/genética , Glucosiltransferases/metabolismo , Isoflavonas/biossíntese , Anti-Inflamatórios/química , Anti-Inflamatórios/farmacologia , Biotransformação , Estabilidade de Medicamentos , Fermentação , Vetores Genéticos , Glucosídeos/química , Glucosídeos/farmacologia , Isoflavonas/química , Isoflavonas/metabolismo , Isoflavonas/farmacologia , Estrutura Molecular , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/genética , Solubilidade
7.
Molecules ; 24(19)2019 Sep 24.
Artigo em Inglês | MEDLINE | ID: mdl-31554155

RESUMO

Ganoderic acid A (GAA) is a bioactive triterpenoid isolated from the medicinal fungus Ganoderma lucidum. Our previous study showed that the Bacillus subtilis ATCC (American type culture collection) 6633 strain could biotransform GAA into compound (1), GAA-15-O-ß-glucoside, and compound (2). Even though we identified two glycosyltransferases (GT) to catalyze the synthesis of GAA-15-O-ß-glucoside, the chemical structure of compound (2) and its corresponding enzyme remain elusive. In the present study, we identified BsGT110, a GT from the same B. subtilis strain, for the biotransformation of GAA into compound (2) through acidic glycosylation. BsGT110 showed an optimal glycosylation activity toward GAA at pH 6 but lost most of its activity at pH 8. Through a scaled-up production, compound (2) was successfully isolated using preparative high-performance liquid chromatography and identified to be a new triterpenoid glucoside (GAA-26-O-ß-glucoside) by mass and nuclear magnetic resonance spectroscopy. The results of kinetic experiments showed that the turnover number (kcat) of BsGT110 toward GAA at pH 6 (kcat = 11.2 min-1) was 3-fold higher than that at pH 7 (kcat = 3.8 min-1), indicating that the glycosylation activity of BsGT110 toward GAA was more active at acidic pH 6. In short, we determined that BsGT110 is a unique GT that plays a role in the glycosylation of triterpenoid at the C-26 position under acidic conditions, but loses most of this activity under alkaline ones, suggesting that acidic solutions may enhance the catalytic activity of this and similar types of GTs toward triterpenoids.


Assuntos
Bacillus subtilis/enzimologia , Glucosídeos/biossíntese , Glicosiltransferases/metabolismo , Ácidos Heptanoicos/metabolismo , Lanosterol/análogos & derivados , Proteínas Recombinantes , Triterpenos/metabolismo , Sequência de Aminoácidos , Biotransformação , Catálise , Cromatografia Líquida de Alta Pressão , Glucosídeos/química , Glicosilação , Ácidos Heptanoicos/química , Cinética , Lanosterol/química , Lanosterol/metabolismo , Triterpenos/química
8.
Int J Mol Sci ; 19(11)2018 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-30400606

RESUMO

Bacillus subtilis ATCC (American type culture collection) 6633 was found to biotransform ganoderic acid A (GAA), which is a major lanostane triterpenoid from the medicinal fungus Ganoderma lucidum. Five glycosyltransferase family 1 (GT1) genes of this bacterium, including two uridine diphosphate-dependent glycosyltransferase (UGT) genes, BsUGT398 and BsUGT489, were cloned and overexpressed in Escherichia coli. Ultra-performance liquid chromatography confirmed the two purified UGT proteins biotransform ganoderic acid A into a metabolite, while the other three purified GT1 proteins cannot biotransform GAA. The optimal enzyme activities of BsUGT398 and BsUGT489 were at pH 8.0 with 10 mM of magnesium or calcium ion. In addition, no candidates showed biotransformation activity toward antcin K, which is a major ergostane triterpenoid from the fruiting bodies of Antrodia cinnamomea. One biotransformed metabolite from each BsUGT enzyme was then isolated with preparative high-performance liquid chromatography. The isolated metabolite from each BsUGT was identified as ganoderic acid A-15-O-ß-glucoside by mass and nuclear magnetic resonance spectroscopy. The two BsUGTs in the present study are the first identified enzymes that catalyze the 15-O-glycosylation of triterpenoids.


Assuntos
Bacillus subtilis/enzimologia , Biocatálise , Glicosiltransferases/metabolismo , Ácidos Heptanoicos/metabolismo , Lanosterol/análogos & derivados , Difosfato de Uridina/metabolismo , Biotransformação , Glicosilação , Ácidos Heptanoicos/química , Concentração de Íons de Hidrogênio , Íons , Lanosterol/química , Lanosterol/metabolismo , Metais/farmacologia , Filogenia , Temperatura
9.
Molecules ; 23(9)2018 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-30217066

RESUMO

Functional bacteria that could biotransform triterpenoids may exist in the diverse microflora of fish intestines. Ganoderic acid A (GAA) is a major triterpenoid from the medicinal fungus Ganoderma lucidum. In studying the microbial biotransformation of GAA, dozens of intestinal bacteria were isolated from the excreta of zebrafish. The bacteria's ability to catalyze GAA were determined using ultra-performance liquid chromatography analysis. One positive strain, GA A07, was selected for functional studies. GA A07 was confirmed as Bacillus sp., based on the DNA sequences of the 16S rRNA gene. The biotransformed metabolite was purified with the preparative high-performance liquid chromatography method and identified as GAA-15-O-ß-glucoside, based on the mass and nuclear magnetic resonance spectral data. The present study is the first to report the glycosylation of Ganoderma triterpenoids. Moreover, 15-O-glycosylation is a new microbial biotransformation of triterpenoids, and the biotransformed metabolite, GAA-15-O-ß-glucoside, is a new compound.


Assuntos
Bactérias/classificação , Triterpenos/química , Peixe-Zebra/microbiologia , Animais , Bacillus/classificação , Bacillus/genética , Bacillus/isolamento & purificação , Bacillus/metabolismo , Bactérias/genética , Bactérias/isolamento & purificação , Bactérias/metabolismo , Catálise , Cromatografia Líquida de Alta Pressão , Microbioma Gastrointestinal , Glicosilação , Filogenia , RNA Ribossômico 16S/genética
10.
Molecules ; 22(1)2017 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-28054996

RESUMO

Biotransformation of the soy isoflavone genistein by sequential 3'-hydroxylation using recombinant Escherichia coli expressing tyrosinase from Bacillus megaterium and then methylation using another recombinant E. coli expressing O-methyltransferase from Streptomyces peucetius was conducted. The results showed that two metabolites were produced from the biotransformation, identified as 5,7,4'-trihydroxy-3'-methoxyisoflavone and 5,7,3'-trihydroxy-4'-methoxyisoflavone, respectively, based on their mass and nuclear magnetic resonance spectral data. 5,7,4'-Trihydroxy-3'-methoxyisoflavone showed potent antiproliferative activity toward mouse B16 melanoma cells with an IC50 value of 68.8 µM. In contrast, the compound did not show any cytotoxicity toward mouse normal fibroblast cells, even at 350 µM concentration. The results of the present study offer insight on the production of both 5,7,4'-trihydroxy-3'-methoxyisoflavone and 5,7,3'-trihydroxy-4'-methoxyisoflavone by two recombinant E. coli strains and the potential anti-melanoma applications of 5,7,4'-trihydroxy-3'-methoxyisoflavone.


Assuntos
Antineoplásicos Fitogênicos/biossíntese , Proteínas de Bactérias/metabolismo , Escherichia coli/metabolismo , Isoflavonas/biossíntese , Metiltransferases/metabolismo , Monofenol Mono-Oxigenase/metabolismo , Animais , Antineoplásicos Fitogênicos/isolamento & purificação , Antineoplásicos Fitogênicos/farmacologia , Bacillus megaterium/química , Bacillus megaterium/enzimologia , Proteínas de Bactérias/genética , Biotransformação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Escherichia coli/química , Escherichia coli/genética , Fibroblastos/efeitos dos fármacos , Genisteína/metabolismo , Hidroxilação , Concentração Inibidora 50 , Isoflavonas/isolamento & purificação , Isoflavonas/farmacologia , Melanoma Experimental/patologia , Engenharia Metabólica/métodos , Metilação , Metiltransferases/genética , Camundongos , Monofenol Mono-Oxigenase/genética , Especificidade de Órgãos , Organismos Geneticamente Modificados/genética , Organismos Geneticamente Modificados/metabolismo , Streptomyces/química , Streptomyces/enzimologia , Transgenes
11.
Planta Med ; 80(2-3): 243-8, 2014 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-24488716

RESUMO

S-adenosyl-L-methionine is a ubiquitous methyl donor in living bodies. It is known to participate in several physiological processes including homocysteine metabolism and glutathione synthesis regulation, and cellular antioxidant mechanism. S-adenosyl-L-methionine containing dietary supplements has been prescribed recently for the treatment of depression, arthritis, and liver diseases with encouraging results. The development of an efficient analytical protocol for S-adenosyl-L-methionine containing dietary supplements is crucial for maintaining product quality and consumer health. In this study, the S-adenosyl-L-methionine content of several yeast products and commercial healthy food product samples was quantitatively analyzed utilizing HPLC. The chromatographic separation was achieved on a reversed-phase column and 2 % acetonitrile with a 98 % ammonium-acetate mobile phase under pH 4.5, with a flow rate of 1.0 mL/min. The wavelength used for detection with the UV detector was 254 nm. The total analysis time was short and the target compound showed a well-defined peak. The correlation coefficient of the regression curve showed good linearity and sensitivity with r = 0.999. All experiments were replicated five times and the relative standard deviations as well as the relative error values were all less than 3 %. Moreover, the achieved precision and accuracy values were high with 97.4-100.9 % recovery. Qualitative determination of S-adenosyl-L-methionine in the tested products was achieved using NMR and LC-MS techniques. The developed protocol is robust, fast, and suitable for the quality control analysis of yeast and commercial S-adenosyl-L-methionine products.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Suplementos Nutricionais , S-Adenosilmetionina/química , Cromatografia Líquida , Cromatografia de Fase Reversa , Espectrometria de Massas , S-Adenosilmetionina/isolamento & purificação , Saccharomyces cerevisiae/química
12.
J Biosci Bioeng ; 137(1): 47-53, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38036317

RESUMO

Our pursuit of new compounds with enhanced bioavailability and bioactivity prompted us to employ the biotransformation-guided purification (BGP) approach which leverages proficient in vitro biotransformation techniques. Angelica dahurica roots, also called Baizhi in Chinese traditional medicine, are famous for their anti-inflammatory and analgesic properties. Herein, we applied the BGP methodology to Baizhi extracts, employing Deinococcus geothermalis amylosucrase (DgAS), an enzyme demonstrating catalytic competence across diverse substrates, for biotransformation. Initiating with a 70 % methanol extraction, we obtained the crude extract of commercial Baizhi powder, followed by an additional extraction using ethyl acetate. Notably, reactions performed on this extract yielded limited quantities of novel compounds. Subsequently, the extract underwent partitioning into four fractions based on HPLC profiling, leading to the successful isolation of a compound with significant yield from fraction 2 mixtures upon reaction with DgAS. Structural elucidation confirmed the compound as byakangelicin-7″-O-α-glucopyranoside (BG-G), a new alpha glycoside derivative of byakangelicin. Furthermore, validation experiments verified the capacity of DgAS to glycosylate pure byakangelicin, yielding BG-G. Remarkably, the aqueous solubility of BG-G exceeded that of byakangelicin by over 29,000-fold. In conclusion, BGP emerges as a potent strategy combining traditional medicinal insights with robust enzymatic tools for generating new compounds.


Assuntos
Glicosídeos , Medicina Tradicional Chinesa , Glucosiltransferases/metabolismo , Biotransformação
13.
J Biosci Bioeng ; 138(3): 218-224, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38997871

RESUMO

Gingerols are phenolic biomedical compounds found in ginger (Zingiber officinale) whose low aqueous solubility limits their medical application. To improve their solubility and produce novel glucosides, an α-glucosidase (glycoside hydrolase) from Agrobacterium radiobacter DSM 30147 (ArG) was subcloned, expressed, purified, and then confirmed to have additional α-glycosyltransferase activity. After optimization, the ArG could glycosylate gingerols into three mono-glucosides based on the length of their acyl side chains. Compound 1 yielded 63.0 %, compound 2 yielded 26.9 %, and compound 3 yielded 4.37 %. The production yield of the gingerol glucosides optimally increased in 50 mM phosphate buffer (pH 6) with 50 % (w/v) maltose and 1000 mM Li+ at 40 °C for an 24-h incubation. The structures of purified compound 1 and compound 2 were determined as 6-gingerol-5-O-α-glucoside (1) and novel 8-gingerol-5-O-α-glucoside (2), respectively, using nucleic magnetic resonance and mass spectral analyses. The aqueous solubility of the gingerol glucosides was greatly improved. Further assays showed that, unusually, 6-gingerol-5-O-α-glucoside had 10-fold higher anti-inflammatory activity (IC50 value of 15.3 ± 0.5 µM) than 6-gingerol, while the novel 8-gingerol-5-O-α-glucoside retained 42.7 % activity (IC50 value of 106 ± 4 µM) compared with 8-gingerol. The new α-glucosidase (ArG) was confirmed to have acidic α-glycosyltransferase activity and could be applied in the production of α-glycosyl derivatives. The 6-gingerol-5-O-α-glucoside can be applied as a clinical drug for anti-inflammatory activity.


Assuntos
Agrobacterium tumefaciens , Anti-Inflamatórios , Catecóis , Álcoois Graxos , Glucosídeos , alfa-Glucosidases , Álcoois Graxos/química , Álcoois Graxos/farmacologia , Álcoois Graxos/metabolismo , alfa-Glucosidases/metabolismo , alfa-Glucosidases/química , Catecóis/química , Catecóis/farmacologia , Catecóis/metabolismo , Glucosídeos/química , Glucosídeos/farmacologia , Glucosídeos/metabolismo , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/química , Solubilidade , Zingiber officinale/química
14.
J Biosci Bioeng ; 135(5): 402-410, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36889998

RESUMO

Ganoderma sp. contains high amounts of diverse triterpenoids; however, few triterpenoid saponins could be isolated from the medicinal fungus. To produce novel Ganoderma triterpenoid saponins, biotransformation-guided purification (BGP) process was applied to a commercial Ganoderma extract. The commercial Ganoderma extract was partially separated into three fractions by preparative high-performance liquid chromatography, and the separated fractions were then directly biotransformed by a Bacillus glycosyltransferase (BsUGT489). One of the biotransformed products could be further purified and identified as a novel saponin: ganoderic acid C2 (GAC2)-3-O-ß-glucoside by nucleic magnetic resonance (NMR) and mass spectral analyses. Based on the structure of the saponin, the predicted precursor should be the GAC2, which was confirmed to be biotransformed into four saponins, GAC2-3-O-ß-glucoside, GAC2-3,15-O-ß-diglucoside and two unknown GAC2 monoglucosides, revealed by NMR and mass spectral analyses. GAC2-3-O-ß-glucoside and GAC2-3,15-O-ß-diglucoside possessed 17-fold and 200-fold higher aqueous solubility than that of GAC2, respectively. In addition, GAC2-3-O-ß-glucoside retained the most anti-α-glucosidase activity of GAC2 and was comparable with that of the anti-diabetes drug (acarbose). The present study showed that the BGP process is an efficient strategy to survey novel and bioactive molecules from crude extracts of natural products.


Assuntos
Ganoderma , Saponinas , Triterpenos , Ganoderma/química , Biotransformação , Glucosídeos
15.
Plants (Basel) ; 11(17)2022 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-36079584

RESUMO

This study demonstrated the enzymatic hydroxylation of glycitin to 3'-hydroxyglycitin, confirming the structure by mass and nucleic magnetic resonance spectral analyses. The bioactivity assays further revealed that the new compound possessed over 100-fold higher 1,1-diphenyl-2-picrylhydrazine free-radical scavenging activity than the original glycitin, although its half-time of stability was 22.3 min. Furthermore, the original glycitin lacked anti-α-glucosidase activity, whereas the low-toxic 3'-hydroxyglycitin displayed a 10-fold higher anti-α-glucosidase activity than acarbose, a standard clinical antidiabetic drug. The inhibition mode of 3'-hydroxyglycitin was noncompetitive, with a Ki value of 0.34 mM. These findings highlight the potential use of the new soy isoflavone 3'-hydroxyglycitin in biotechnology industries in the future.

16.
Plants (Basel) ; 11(17)2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-36079669

RESUMO

Ha-Soo-Oh is a traditional Chinese medicine prepared from the roots of Polygonum multiflorum Thunb. The herb extract has been widely used in Asian countries as a tonic agent and nutritional supplement for centuries. To identify new bioactive compounds in Chinese herbs, the biotransformation-guided purification (BGP) process was applied to Ha-Soo-Oh with Bacillus megaterium tyrosinase (BmTYR) as a biocatalyst. The result showed that a major biotransformed compound could be purified using the BGP process with preparative high-performance liquid chromatography (HPLC), and it was confirmed as a new compound, 2,3,5,3',4'-pentahydroxystilbene-2-O-ß-glucoside (PSG) following mass and nucleic magnetic resonance (NMR) spectral analyses. PSG was further confirmed as a biotransformation product from 2,3,5,4'-tetrahydroxystilbene-2-O-ß-glucoside (TSG) by BmTYR. The new PSG exhibited 4.7-fold higher 1,1-diphenyl-2-picrylhydrazine (DPPH) free radical scavenging activity than that of TSG. The present study highlights the potential usage of BGP in herbs to discover new bioactive compounds in the future.

17.
Biology (Basel) ; 11(6)2022 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35741343

RESUMO

Glycosylation occurring at either lipids, proteins, or sugars plays important roles in many biological systems. In nature, enzymatic glycosylation is the formation of a glycosidic bond between the anomeric carbon of the donor sugar and the functional group of the sugar acceptor. This study found novel glycoside anomers without an anomeric carbon linkage of the sugar donor. A glycoside hydrolase (GH) enzyme, amylosucrase from Deinococcus geothermalis (DgAS), was evaluated to glycosylate ganoderic acid F (GAF), a lanostane triterpenoid from medicinal fungus Ganoderma lucidum, at different pH levels. The results showed that GAF was glycosylated by DgAS at acidic conditions pH 5 and pH 6, whereas the activity dramatically decreased to be undetectable at pH 7 or pH 8. The biotransformation product was purified by preparative high-performance liquid chromatography and identified as unusual α-glucosyl-(2→26)-GAF and ß-glucosyl-(2→26)-GAF anomers by mass and nucleic magnetic resonance (NMR) spectroscopy. We further used DgAS to catalyze another six triterpenoids. Under the acidic conditions, two of six compounds, ganoderic acid A (GAA) and ganoderic acid G (GAG), could be converted to α-glucosyl-(2→26)-GAA and ß-glucosyl-(2→26)-GAA anomers and α-glucosyl-(2→26)-GAG and ß-glucosyl-(2→26)-GAG anomers, respectively. The glycosylation of triterpenoid aglycones was first confirmed to be converted via a GH enzyme, DgAS. The novel enzymatic glycosylation-formed glycoside anomers opens a new bioreaction in the pharmaceutical industry and in the biotechnology sector.

18.
Biosci Biotechnol Biochem ; 75(5): 914-8, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21597196

RESUMO

Our previous study showed that a methanol extract from Trifolium pratense exerted potent inhibitory activity on melanogenesis in mouse B16 melanoma cells. In the present study, the active compound in this Chinese herb extract was isolated and identified as biochanin A by mass spectrum, (1)H-NMR, and (13)C-NMR analysis. The inhibitory effects of biochanin A on melanogenesis were investigated in vitro in cultured melanoma cells and in vivo in zebrafish and mice. Biochanin A dose-dependently inhibited both melanogenesis and cellular tyrosinase activity in B16 cells and in zebrafish embryos. Application of a cream containing 2% biochanin A twice daily to the skin of mice also increased the skin-whitening index value after 1 week of treatment, and the increase continued for another 2 weeks. Biochanin A was confirmed as a good candidate for use as a skin-whitening agent in the treatment of skin hyperpigmentation disorders.


Assuntos
Genisteína/farmacologia , Melaninas/biossíntese , Trifolium/química , Animais , Linhagem Celular Tumoral , Genisteína/análise , Genisteína/isolamento & purificação , Humanos , Camundongos , Pigmentação/efeitos dos fármacos , Peixe-Zebra
19.
Int J Mol Sci ; 12(8): 4819-35, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21954327

RESUMO

Melanogenesis inhibition by raspberry ketone (RK) from Rheum officinale was investigated both in vitro in cultivated murine B16 melanoma cells and in vivo in zebrafish and mice. In B16 cells, RK inhibited melanogenesis through a post-transcriptional regulation of tyrosinase gene expression, which resulted in down regulation of both cellular tyrosinase activity and the amount of tyrosinase protein, while the level of tyrosinase mRNA transcription was not affected. In zebrafish, RK also inhibited melanogenesis by reduction of tyrosinase activity. In mice, application of a 0.2% or 2% gel preparation of RK applied to mouse skin significantly increased the degree of skin whitening within one week of treatment. In contrast to the widely used flavoring properties of RK in perfumery and cosmetics, the skin-whitening potency of RK has been demonstrated in the present study. Based on our findings reported here, RK would appear to have high potential for use in the cosmetics industry.


Assuntos
Butanonas/farmacologia , Exsudatos de Plantas/farmacologia , Rheum/química , Preparações Clareadoras de Pele/farmacologia , Animais , Butanonas/química , Butanonas/isolamento & purificação , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Ativação Enzimática/efeitos dos fármacos , Melanoma Experimental , Camundongos , Monofenol Mono-Oxigenase/metabolismo , Exsudatos de Plantas/química , Exsudatos de Plantas/isolamento & purificação , Preparações Clareadoras de Pele/química , Preparações Clareadoras de Pele/isolamento & purificação , Fatores de Tempo , Peixe-Zebra
20.
Antioxidants (Basel) ; 10(11)2021 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-34829688

RESUMO

Mangiferin is a natural antioxidant C-glucosidic xanthone originally isolated from the Mangifera indica (mango) plant. Mangiferin exhibits a wide range of pharmaceutical activities. However, mangiferin's poor solubility limits its applications. To resolve this limitation of mangiferin, enzymatic glycosylation of mangiferin to produce more soluble mangiferin glucosides was evaluated. Herein, the recombinant maltogenic amylase (MA; E.C. 3.2.1.133) from a thermophile Parageobacillus galactosidasius DSM 18751T (PgMA) was cloned into Escherichia coli BL21 (DE3) via the expression plasmid pET-Duet-1. The recombinant PgMA was purified via Ni2+ affinity chromatography. To evaluate its transglycosylation activity, 17 molecules, including mangiferin (as sugar acceptors), belonging to triterpenoids, saponins, flavonoids, and polyphenol glycosides, were assayed with ß-CD (as the sugar donor). The results showed that puerarin and mangiferin are suitable sugar acceptors in the transglycosylation reaction. The glycosylation products from mangiferin by PgMA were isolated using preparative high-performance liquid chromatography. Their chemical structures were glucosyl-α-(1→6)-mangiferin and maltosyl-α-(1→6)-mangiferin, determined by mass and nucleic magnetic resonance spectral analysis. The newly identified maltosyl-α-(1→6)-mangiferin showed 5500-fold higher aqueous solubility than that of mangiferin, and both mangiferin glucosides exhibited similar 1,1-diphenyl-2-picrylhydrazyl free radical scavenging activities compared to mangiferin. PgMA is the first MA with glycosylation activity toward mangiferin, meaning mangiferin glucosides have potential future applications.

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