Minocycline has been widely used in clinical treatment and its residues were considered to have environmental safety risks due to complex chemical structure.Therefore,it is necessary to find an efficient and environme...Minocycline has been widely used in clinical treatment and its residues were considered to have environmental safety risks due to complex chemical structure.Therefore,it is necessary to find an efficient and environmentally friendly method to remove minocycline from the environment.This study screened and isolated a minocycline degrading strain DM13 from the activated sludge for municipal sewage pipeline,and optimized the biodegradation of minocycline by DM13 under various environmental conditions.The maximum biodegradation efficiency of 50 mg/L minocycline reached 93%at 72 h with the temperature of 30℃,the initial pH of 7.0,and the inoculation rate of 3%.Two potential biotransformation pathways were proposed,including deamination,demethylation,and decarbonylation.The acute toxicity assessment showed that the biotransformation products of minocycline had lower toxicity than the parent compound.In addition,the first-generation tetracycline antibiotics could be removed,suggesting that strain DM13 has the potential for application in treating antibiotic wastewater.展开更多
Prodrugs need to be converted to active drugs to exert their pharmacological activities.Identifying the direct targets of active drugs is essential to elucidate the pharmacological mechanisms of prodrugs,but remains c...Prodrugs need to be converted to active drugs to exert their pharmacological activities.Identifying the direct targets of active drugs is essential to elucidate the pharmacological mechanisms of prodrugs,but remains challenging,especially for active drugs with low stability.展开更多
Microbial transformation of gastrodin by Mucor spinosus strain 3.3450, resulted in a product with a transformation rate close to 100 per cent. This product was identified as p-hydroxy benzyl alcohol on the basis of it...Microbial transformation of gastrodin by Mucor spinosus strain 3.3450, resulted in a product with a transformation rate close to 100 per cent. This product was identified as p-hydroxy benzyl alcohol on the basis of its 1H, 13C NMR and EI-MS spectral data. It could be inferred that the enzyme responsible for the biotransforma-tion reaction was a kind of extracellular and constitutive enzyme since the transformation reaction of the substrate could be carried out in cell free extracts of the fermentation broth of the Mucor spinosus.展开更多
The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled t...The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled to growth phases:the fractal dimension,a feature calculated from the morphological images,increases during the late lag phase and the early exponential phase,and culminates at a value near 2.4 at half of the exponential phase.This can be attributed to the marked change of rough and smooth pellet proportions during growth and the change can be well expressed by the fractal analysis of mycelial morphology.The mycelial morphology is also strongly related to the biotransformation activity:a mycelial sample was withdrawn from the culture to use for fractal analysis before the steroid substrate (16α,17α epoxy 4 pregnene 3,20 dione) was added;the higher fractal dimension corresponds to the higher conversion rate of steroid biotransformation.And the maximum of fractal dimension appeared prior to the maximum of biomass concentration.It is therefore possible to utilize the fractal dimension curve to supervise the fermentation process more timely and availably than to use the conventional biomass curve to do.展开更多
[ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ab...[ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ability and reducing capacity of DPPH as well as inhibitory rate of nonenzymatic glycation reaction were measured targets for comparing changes of anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of fermentation lyophilizer and fermentation extraction before and after EGB fermention adsorbed by AB-8 macroporous resin. The EGB fermention was biotransformed by Hericium erinaceus. [ Result ] After adsorbed by AB-8 macroporous resin, the bioactive matters were concentrated and separated. The free radical scavenging rate, reducing capacity and inhibitory rate of nonenzymatic glycation reaction were increased significantly after adsorbed by AB-8 macroporous resin. [ Conclusion] AB-8 macroporous resin could be used for preliminary concentration of EGB fermentation which was biotransformed by Hericium erinaceus.展开更多
The biotransformation of artemisinin by hairy root cultures ofRheum palmatum L. was investigated for the first time. The main product, deoxyartemisinin, was isolated and characterized on the basis of its spectral data.
Naringin （1）, the highest-content flavanone glycoside in sour oranges, was incubated with human intestinal flora, and four biotransforrnation products （2-5） were obtained from the incubated mixture by chromatograp...Naringin （1）, the highest-content flavanone glycoside in sour oranges, was incubated with human intestinal flora, and four biotransforrnation products （2-5） were obtained from the incubated mixture by chromatographic methods. The chemical structures of the four products were elucidated as naringin-6＂acetate （2）, naringenin （3）, phloretic acid （4）, and phloroglucinol （5） on the basis of their spectroscopic data. Naringin-6＂-acetate was specifically formed by acetylation at C6-OH of glucosyl group of 1. The result obtained in the present research could account for the lower bioavailability of 1 after oral administration, suggesting that some biological properties of 1 in vivo may be mediated by its intestinal flora converted product 3. The biotransforrnation of 1 by intestinal flora leading to their systemic absorption deserves further attention and may provide valuable insights into pre-systemic drug metabolism, delivery or toxicity.展开更多
Methyleugenol （1）, one of the main bioactive constituents of the seeds of Myristicafragrans Houtt. （family： Myristicaceae）, was incubated with rat hepatic microsomes from rats pretreated with sodium phenobarbital...Methyleugenol （1）, one of the main bioactive constituents of the seeds of Myristicafragrans Houtt. （family： Myristicaceae）, was incubated with rat hepatic microsomes from rats pretreated with sodium phenobarbital. Eight biotransformation products named （R）-l＇-methoxymethyleugenol （2）, 3-（3,4-dimethoxyphenyl）-l-methoxyprop-2-ene （3）, cis-3,4-dimethoxycinnamyl acetate （4）, trans-3,4-dimethoxycinnamyl acetate （5）, （R）-I hydroxymethyleugenol （6）, trans-3,4-dimethoxycinnamyl alcohol （7）, cis-3,4-dimethoxycinnamyl alcohol （8）, and （R）-3-（3,4-dimethoxyphenyl）-propane-l,2-diol （9） were obtained and their structures were elucidated by NMR and MS data analysis and by comparison with the previously reported data. The biotransformation of 1 may provide valuable information for the use of methyleugenol. The NMR data of compounds 4 and 6 were reported for the first time.展开更多
Dietary uptake is the major way that inorganic arsenic(iAs)enters into benthic fish;however,the metabolic process of dietborne i As in fish muscle following chronic exposure remains unclear.This was a 40-day study on ...Dietary uptake is the major way that inorganic arsenic(iAs)enters into benthic fish;however,the metabolic process of dietborne i As in fish muscle following chronic exposure remains unclear.This was a 40-day study on chronic dietborne i As[arsenite(AsⅢ)and arsenate(AsⅤ)]exposure in the benthic freshwater food fish,the crucian carp(Carassius auratus),which determined the temporal profiles of iAs metabolism and toxicokinetics during exposure.We found that an adaptive response occurred in the fish body after iAs dietary exposure,which was associated with decreased As accumulation and increased As transformation into a non-toxic As form(arsenobetaine).The bioavailability of dietary AsⅢwas lower than that of AsⅤ,probably because AsⅢhas a lower ability to pass through fish tissues.Dietary AsⅤexhibited a high potential for transformation into AsⅢspecies,which then accumulated in fish muscle.The largely produced AsⅢconsidered more toxic at the earlier stage of AsⅤexposure should attract sufficient attention to human exposure assessment.Therefore,the pristine As species and exposure duration had significant effects on As bioaccumulation and biotransformation in fish.The behavior determined for dietborne arsenic in food fish is crucial for not only arsenic ecotoxicology but also food safety.展开更多
[Objective] The aim was to investigate the effect of four extraction meth- ods on extraction ratio of 11-α-Hydroxy-Canerenone from biotransformation broth. [Method] Previous reported method, soaking, elution method a...[Objective] The aim was to investigate the effect of four extraction meth- ods on extraction ratio of 11-α-Hydroxy-Canerenone from biotransformation broth. [Method] Previous reported method, soaking, elution method and homogenate meth- ods were used. [Result] Results showed that more than 90% of the biotransformed 11-α-Hydroxy-Canerenone existed in the broth supernatant and mycelia surface. Elu- tion and soaking methods were effective for 11-α-Hydroxy-Canerenone extraction. Extraction yields of 96.0% and 98.8% were obtained by eluting with 400 ml of ethy- lacetate and soaking with ethylacetate for 90 min, respectively. [Conelusion] The method is simple and efficient, showing industrial application potential.展开更多
AIM： To observe the biotransformation process of a Chinese compound, aesculin, by human gut bacteria, and to identify its metabolites in rat urine.METHODS： Representative human gut bacteria were collected from 20 he...AIM： To observe the biotransformation process of a Chinese compound, aesculin, by human gut bacteria, and to identify its metabolites in rat urine.METHODS： Representative human gut bacteria were collected from 20 healthy volunteers, and then utilized in vitro to biotransform aesculin under anaerobic conditions. At 0, 2, 4, 8, 12, 16, 24, 48 and 72 h postincubation, 10 mL of culture medium was collected. Metabolites of aesculin were extracted 3 × from rat urine with methanol and analyzed by HPLC. For in vivo metabolite analysis, aesculetin （100 mg/kg） was administered to rats via stomach gavage, rat urine was collected from 6 to 48 h post-administration, and metabolite analysis was performed by LC/ESI-MS and MS/MS in the positive and negative modes.RESULTS： Human gut bacteria could completely convert aesculin into aesculetin in vitro. The biotransformation process occurred from 8 to 24 h post-incubation, with its highest activity was seen from 8 to 12 h. The in vitro process was much slower than the in vivo process. In contrast to the in vitro model, six aesculetin metabolites were identified in rat urine, including 6-hydroxy-7-glucocoumarin（M1）, 6-hydroxy-7-sulf-coumarin （M2）, 6, 7-digluco-coumarin （M3）, 6-glc-7-gluco-coumarin （M4）, 6-O-methyl-7-gluco-coumarin （MS） and 6-O-methyl-7- sulf-coumarin （M6）. Of which, M2 and M6 were novel metabolites.CONCLUSION： Aesculin can be transferred into aesculetin by human gut bacteria and is further modified by the host in vivo. The diverse metabolites of aesculin may explain its pleiotropic pharmaceutical effects.展开更多
OBJECTIVE:To study the absorption and biotransformation of liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid in the Guizhi decoction (GZD) in the gastrointestinal tracts of rats.METHODS:A simple and reliable...OBJECTIVE:To study the absorption and biotransformation of liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid in the Guizhi decoction (GZD) in the gastrointestinal tracts of rats.METHODS:A simple and reliable high-performance liquid chromatography method was established and validated for the analysis of the four components of GZD simultaneously in the gastrointestinal tracts of rats.Rats were randomly divided into in situ gastrointestinal loop model,in vitro anaerobic culture model,and blank control groups.All rats were fasted for 12 h and anesthetized using 20% urethane.Subsequently,the abdominal cavity of each rat was opened,and the stomach,duodenum,jejunum,ileum,cecum,and colon were ligated.For the in situ gastrointestinal loop model group,2.5 mL of GZD (1.0 g crude drug/mL,37 ℃)were injected into the gastrointestinal tract.The abdominal incision was covered with warm,wet cotton,and animals were maintained at 25 ℃.Then,we collected the gastrointestinal tract content after 1.5 h.For the in vitro anaerobic culture model group,the gastrointestinal tract contents of rats were collected and then cultured in 2.5 mL of GZD in an anaerobic environment at 25 ℃ for 24 h.For the blank control group,rats received the same volume of a normal saline solution instead of GZD.High performance liquid chromatography was used to detect the liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid concentrations in each group and calculate the absorption and biotransformation rates of each ingredient.RESULTS:Cinnamic acid (low polarity) was more easily absorbed by each gastrointestinal part than the higher-polarity glycosides.However,the absorption rate in the cecum was higher than that in other parts.The four compounds,cinnamic acid,liquiritin,paeoniflorin,and glycyrrhizic acid,were transformed completely within 24 h in the cecum and colon,whereas they were hardly transformed in the stomach,excluding glycyrrhizic acid.In addition,all ingredients had higher biotransformation rates in the distal small intestine than that in the proximal small intestine.CONCLUSION:Although a portion of the glycosides in GZD was directly absorbed as the prototype forms in the gastrointestinal tract,they were primarily metabolized and transformed into their corresponding metabolites by intestinal flora near the distal small intestine before their absorption.展开更多
Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liqu...Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.展开更多
Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dis...Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these coselection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance(MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.展开更多
A laboratory-scale bioreactor with polyethylene semi-soft packing was constructed and utilized to determine the efficlency of sulfide biotransformation to sulfur under various operating parameters. Sodium sulfide diss...A laboratory-scale bioreactor with polyethylene semi-soft packing was constructed and utilized to determine the efficlency of sulfide biotransformation to sulfur under various operating parameters. Sodium sulfide dissolved in tap water was pumped into the bioreactor as sulfide for biological desulfurization. The sulfide, sulfur and sulfate-S in the effluent and the sulfide purged as gas-phase HzS were determined to investigate the effects of operating parameters, such as pH, DO, hydraulic retention time （HRT）, temperature and salinity, on the sulfide oxidation products. The activity of bacteria was highest at pH 7.8-8.2. The maximal sulfide removal load was 7.25 kg/（m^3·day）, with a 322.07 mg/L influent sulfide concentration and 4.80 mg/L DO. The increase of DO value corresponds to a decrease in the sulfur yield. The reactor had the highest sulfide removal load and sulfur yield at 2.55 mg/L DO. HRT had little effect on desulfurization efficiency when the sulfide removal load was kept constant. The most effective desulfurization temperature was 33℃. The sulfide removal load decreased from 2.85 to 0.51 kg/（m^3.day） with increasing salinity from 0.5% to 2.5% （m/m）.展开更多
Many natural products can be bio-converted by the gut microbiota to influence pertinent efficiency.Ginsenoside compound K(GCK)is a potential anti-type 2 diabetes(T2D)saponin,which is mainly bio-transformed into protop...Many natural products can be bio-converted by the gut microbiota to influence pertinent efficiency.Ginsenoside compound K(GCK)is a potential anti-type 2 diabetes(T2D)saponin,which is mainly bio-transformed into protopanaxadiol(PPD)by the gut microbiota.Studies have shown that the gut microbiota between diabetic patients and healthy subjects are significantly different.Herein,we aimed to characterize the biotransformation of GCK mediated by the gut microbiota from diabetic patients and healthy subjects.Based on 16S rRNA gene sequencing,the results indicated the bacterial profiles were considerably different between the two groups,especially Alistipes and Parabacteroides that increased in healthy subjects.The quantitative analysis of GCK and PPD showed that gut microbiota from the diabetic patients metabolized GCK slower than healthy subjects through liquid chromatography tandem mass spectrometry(LC-MS/MS).The selected strain A.finegoldi and P.merdae exhibited a different metabolic capability of GCK.In conclusion,the different biotransformation capacity for GCK may impact its anti-diabetic potency.展开更多
Deacetoxy-13-oxo sinenxan A (1) was converted to 9a-hydroxy-13-oxo-2a, 5a, 10b-triacetoxy-4(20),11-taxadiene (2) and 10b-hydroxy-13-oxo-2a,5a,9a-triacetoxy- 4(20), 11- taxadiene (3) by Ginkgo cell suspension cultures ...Deacetoxy-13-oxo sinenxan A (1) was converted to 9a-hydroxy-13-oxo-2a, 5a, 10b-triacetoxy-4(20),11-taxadiene (2) and 10b-hydroxy-13-oxo-2a,5a,9a-triacetoxy- 4(20), 11- taxadiene (3) by Ginkgo cell suspension cultures in 45% and 15% yields, respectively.展开更多
Biotransformation ofα-asarone by Alternaria longipes CGMCC 3.2875 yielded two pairs of new neolignans,(+)(7 S,8 S,7’S,8’R)iso-magnosalicin(1 a)/(-)(7 R,8 R,7’R,8’S)iso-magnosalicin(1 b)and(+)(7 R,8 R,7’S,8’R)ma...Biotransformation ofα-asarone by Alternaria longipes CGMCC 3.2875 yielded two pairs of new neolignans,(+)(7 S,8 S,7’S,8’R)iso-magnosalicin(1 a)/(-)(7 R,8 R,7’R,8’S)iso-magnosalicin(1 b)and(+)(7 R,8 R,7’S,8’R)magnosalicin(2 a)/(-)(7 S,8 S,7’R,8’S)magnosalicin(2 b),and four known metabolites,(±)acoraminol A(3),(±)acoraminol B(4),asaraldehyde(5),and 2,4,5-trimethoxybenzoic acid(6).Their structures,including absolute configurations,were determined by extensive analysis of NMR spectra,X-ray crystallography,and quantum chemical ECD calculations.The cytotoxic activity and Aβ_(42)aggregation inhibitory activity of all the compounds were evaluated.Compound 2 displayed significant anti-Aβ_(42)aggregation activity with an inhibitory rate of 60.81%(the positive control EGCG:69.17%).In addition the biotransformation pathway ofα-asarone by Alternaria longipes CGMCC 3.2875 was proposed.展开更多
基金supported by the Natural Science Basic Research Program of Shaanxi Province(No.2023-JC-JQ-36).
文摘Minocycline has been widely used in clinical treatment and its residues were considered to have environmental safety risks due to complex chemical structure.Therefore,it is necessary to find an efficient and environmentally friendly method to remove minocycline from the environment.This study screened and isolated a minocycline degrading strain DM13 from the activated sludge for municipal sewage pipeline,and optimized the biodegradation of minocycline by DM13 under various environmental conditions.The maximum biodegradation efficiency of 50 mg/L minocycline reached 93%at 72 h with the temperature of 30℃,the initial pH of 7.0,and the inoculation rate of 3%.Two potential biotransformation pathways were proposed,including deamination,demethylation,and decarbonylation.The acute toxicity assessment showed that the biotransformation products of minocycline had lower toxicity than the parent compound.In addition,the first-generation tetracycline antibiotics could be removed,suggesting that strain DM13 has the potential for application in treating antibiotic wastewater.
基金support from the National Natural Science Foundation of China(Grant Nos.:U21A20407 and 81973467).
文摘Prodrugs need to be converted to active drugs to exert their pharmacological activities.Identifying the direct targets of active drugs is essential to elucidate the pharmacological mechanisms of prodrugs,but remains challenging,especially for active drugs with low stability.
基金The National Outstanding Youth Foundation by NSF of ChinaTrans-Century Training Program Foundation for Talents by the Ministry of Education for financial support.
文摘Microbial transformation of gastrodin by Mucor spinosus strain 3.3450, resulted in a product with a transformation rate close to 100 per cent. This product was identified as p-hydroxy benzyl alcohol on the basis of its 1H, 13C NMR and EI-MS spectral data. It could be inferred that the enzyme responsible for the biotransforma-tion reaction was a kind of extracellular and constitutive enzyme since the transformation reaction of the substrate could be carried out in cell free extracts of the fermentation broth of the Mucor spinosus.
基金National Natural Science Foundation of China forYoung Researcher !(No.2 960 60 0 8) Tianjin Natural ScienceFoundation!
文摘The fermentation with mold metarrhizium anisopliae has been carried out to determine the relationship between mycelial morphology and growth.Like the biomass concentration,the mycelial morphology seems to be coupled to growth phases:the fractal dimension,a feature calculated from the morphological images,increases during the late lag phase and the early exponential phase,and culminates at a value near 2.4 at half of the exponential phase.This can be attributed to the marked change of rough and smooth pellet proportions during growth and the change can be well expressed by the fractal analysis of mycelial morphology.The mycelial morphology is also strongly related to the biotransformation activity:a mycelial sample was withdrawn from the culture to use for fractal analysis before the steroid substrate (16α,17α epoxy 4 pregnene 3,20 dione) was added;the higher fractal dimension corresponds to the higher conversion rate of steroid biotransformation.And the maximum of fractal dimension appeared prior to the maximum of biomass concentration.It is therefore possible to utilize the fractal dimension curve to supervise the fermentation process more timely and availably than to use the conventional biomass curve to do.
基金the Natural Science Foundation of Jiangsu Province (BK2003047)~~
文摘[ Objective] In order to study the anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of EGB fermentation extraction biotransformed by Hericium erinaceus. [ Method ] The free radical scavenging ability and reducing capacity of DPPH as well as inhibitory rate of nonenzymatic glycation reaction were measured targets for comparing changes of anti-oxidation and inhibitory effect on nonenzymatic glycation reaction of fermentation lyophilizer and fermentation extraction before and after EGB fermention adsorbed by AB-8 macroporous resin. The EGB fermention was biotransformed by Hericium erinaceus. [ Result ] After adsorbed by AB-8 macroporous resin, the bioactive matters were concentrated and separated. The free radical scavenging rate, reducing capacity and inhibitory rate of nonenzymatic glycation reaction were increased significantly after adsorbed by AB-8 macroporous resin. [ Conclusion] AB-8 macroporous resin could be used for preliminary concentration of EGB fermentation which was biotransformed by Hericium erinaceus.
文摘The biotransformation of artemisinin by hairy root cultures ofRheum palmatum L. was investigated for the first time. The main product, deoxyartemisinin, was isolated and characterized on the basis of its spectral data.
基金National Sciences and Technology Program of China (Grant No. 2011BAI07B08)"Major New Medicine Project" in Mega-projects of Science Research of China (Grant No. 2009ZX09301-010)
文摘Naringin （1）, the highest-content flavanone glycoside in sour oranges, was incubated with human intestinal flora, and four biotransforrnation products （2-5） were obtained from the incubated mixture by chromatographic methods. The chemical structures of the four products were elucidated as naringin-6＂acetate （2）, naringenin （3）, phloretic acid （4）, and phloroglucinol （5） on the basis of their spectroscopic data. Naringin-6＂-acetate was specifically formed by acetylation at C6-OH of glucosyl group of 1. The result obtained in the present research could account for the lower bioavailability of 1 after oral administration, suggesting that some biological properties of 1 in vivo may be mediated by its intestinal flora converted product 3. The biotransforrnation of 1 by intestinal flora leading to their systemic absorption deserves further attention and may provide valuable insights into pre-systemic drug metabolism, delivery or toxicity.
基金National Natural Science Foundation of China(Grant No.3097386381161120429)National Key Technology R&D Program of China(Grant No.2011BAI07B08)
文摘Methyleugenol （1）, one of the main bioactive constituents of the seeds of Myristicafragrans Houtt. （family： Myristicaceae）, was incubated with rat hepatic microsomes from rats pretreated with sodium phenobarbital. Eight biotransformation products named （R）-l＇-methoxymethyleugenol （2）, 3-（3,4-dimethoxyphenyl）-l-methoxyprop-2-ene （3）, cis-3,4-dimethoxycinnamyl acetate （4）, trans-3,4-dimethoxycinnamyl acetate （5）, （R）-I hydroxymethyleugenol （6）, trans-3,4-dimethoxycinnamyl alcohol （7）, cis-3,4-dimethoxycinnamyl alcohol （8）, and （R）-3-（3,4-dimethoxyphenyl）-propane-l,2-diol （9） were obtained and their structures were elucidated by NMR and MS data analysis and by comparison with the previously reported data. The biotransformation of 1 may provide valuable information for the use of methyleugenol. The NMR data of compounds 4 and 6 were reported for the first time.
基金the Special Fund for AgroScientific Research in the Public Interest of China(No.201503108)the Science and Technology Project of Hunan Province(No.2017WK2091)。
文摘Dietary uptake is the major way that inorganic arsenic(iAs)enters into benthic fish;however,the metabolic process of dietborne i As in fish muscle following chronic exposure remains unclear.This was a 40-day study on chronic dietborne i As[arsenite(AsⅢ)and arsenate(AsⅤ)]exposure in the benthic freshwater food fish,the crucian carp(Carassius auratus),which determined the temporal profiles of iAs metabolism and toxicokinetics during exposure.We found that an adaptive response occurred in the fish body after iAs dietary exposure,which was associated with decreased As accumulation and increased As transformation into a non-toxic As form(arsenobetaine).The bioavailability of dietary AsⅢwas lower than that of AsⅤ,probably because AsⅢhas a lower ability to pass through fish tissues.Dietary AsⅤexhibited a high potential for transformation into AsⅢspecies,which then accumulated in fish muscle.The largely produced AsⅢconsidered more toxic at the earlier stage of AsⅤexposure should attract sufficient attention to human exposure assessment.Therefore,the pristine As species and exposure duration had significant effects on As bioaccumulation and biotransformation in fish.The behavior determined for dietborne arsenic in food fish is crucial for not only arsenic ecotoxicology but also food safety.
基金Supported by National Natural Science Foundation of China(31101269)Industrial Sciences and Technology Supporting Project of Zhenjiang City(GY2011006)+3 种基金International Foundation for Science(F 4930-1)Bio-zymosis and Food Additive Engineering Research Center of Jiangxi ProvinceScientific Technology Condition Platform Establishment Project of Jiangxi(2010DTZ01900)Scientific Research Fund of Jiangsu University(10A229,10A080)~~
文摘[Objective] The aim was to investigate the effect of four extraction meth- ods on extraction ratio of 11-α-Hydroxy-Canerenone from biotransformation broth. [Method] Previous reported method, soaking, elution method and homogenate meth- ods were used. [Result] Results showed that more than 90% of the biotransformed 11-α-Hydroxy-Canerenone existed in the broth supernatant and mycelia surface. Elu- tion and soaking methods were effective for 11-α-Hydroxy-Canerenone extraction. Extraction yields of 96.0% and 98.8% were obtained by eluting with 400 ml of ethy- lacetate and soaking with ethylacetate for 90 min, respectively. [Conelusion] The method is simple and efficient, showing industrial application potential.
基金Supported by Department of Traditional Chinese Medicine,Sichuan Province,No.03JY-002
文摘AIM： To observe the biotransformation process of a Chinese compound, aesculin, by human gut bacteria, and to identify its metabolites in rat urine.METHODS： Representative human gut bacteria were collected from 20 healthy volunteers, and then utilized in vitro to biotransform aesculin under anaerobic conditions. At 0, 2, 4, 8, 12, 16, 24, 48 and 72 h postincubation, 10 mL of culture medium was collected. Metabolites of aesculin were extracted 3 × from rat urine with methanol and analyzed by HPLC. For in vivo metabolite analysis, aesculetin （100 mg/kg） was administered to rats via stomach gavage, rat urine was collected from 6 to 48 h post-administration, and metabolite analysis was performed by LC/ESI-MS and MS/MS in the positive and negative modes.RESULTS： Human gut bacteria could completely convert aesculin into aesculetin in vitro. The biotransformation process occurred from 8 to 24 h post-incubation, with its highest activity was seen from 8 to 12 h. The in vitro process was much slower than the in vivo process. In contrast to the in vitro model, six aesculetin metabolites were identified in rat urine, including 6-hydroxy-7-glucocoumarin（M1）, 6-hydroxy-7-sulf-coumarin （M2）, 6, 7-digluco-coumarin （M3）, 6-glc-7-gluco-coumarin （M4）, 6-O-methyl-7-gluco-coumarin （MS） and 6-O-methyl-7- sulf-coumarin （M6）. Of which, M2 and M6 were novel metabolites.CONCLUSION： Aesculin can be transferred into aesculetin by human gut bacteria and is further modified by the host in vivo. The diverse metabolites of aesculin may explain its pleiotropic pharmaceutical effects.
基金Supported by the National Natural Science Foundation:Based on Serum Fingerprint to Develop a New Method for Preparing Serum Containing Drugs(No.81403282)the Natural Science Foundation of Beijing Municipality:Influence of Intestinal First-Pass Effect on the Curing Effect of Traditional Chinese Medicine(No.7133251)
文摘OBJECTIVE:To study the absorption and biotransformation of liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid in the Guizhi decoction (GZD) in the gastrointestinal tracts of rats.METHODS:A simple and reliable high-performance liquid chromatography method was established and validated for the analysis of the four components of GZD simultaneously in the gastrointestinal tracts of rats.Rats were randomly divided into in situ gastrointestinal loop model,in vitro anaerobic culture model,and blank control groups.All rats were fasted for 12 h and anesthetized using 20% urethane.Subsequently,the abdominal cavity of each rat was opened,and the stomach,duodenum,jejunum,ileum,cecum,and colon were ligated.For the in situ gastrointestinal loop model group,2.5 mL of GZD (1.0 g crude drug/mL,37 ℃)were injected into the gastrointestinal tract.The abdominal incision was covered with warm,wet cotton,and animals were maintained at 25 ℃.Then,we collected the gastrointestinal tract content after 1.5 h.For the in vitro anaerobic culture model group,the gastrointestinal tract contents of rats were collected and then cultured in 2.5 mL of GZD in an anaerobic environment at 25 ℃ for 24 h.For the blank control group,rats received the same volume of a normal saline solution instead of GZD.High performance liquid chromatography was used to detect the liquiritin,cinnamic acid,paeoniflorin,and glycyrrhizic acid concentrations in each group and calculate the absorption and biotransformation rates of each ingredient.RESULTS:Cinnamic acid (low polarity) was more easily absorbed by each gastrointestinal part than the higher-polarity glycosides.However,the absorption rate in the cecum was higher than that in other parts.The four compounds,cinnamic acid,liquiritin,paeoniflorin,and glycyrrhizic acid,were transformed completely within 24 h in the cecum and colon,whereas they were hardly transformed in the stomach,excluding glycyrrhizic acid.In addition,all ingredients had higher biotransformation rates in the distal small intestine than that in the proximal small intestine.CONCLUSION:Although a portion of the glycosides in GZD was directly absorbed as the prototype forms in the gastrointestinal tract,they were primarily metabolized and transformed into their corresponding metabolites by intestinal flora near the distal small intestine before their absorption.
基金the Natural Science Foundation of Guangdong Province (No. 020839).
文摘Ionic liquids have negligibly low vapor pressure, high stability and polarity. They are regarded as green solvents. Enzymes, especially lipases, as well as whole-cell of microbe, are catalytically active in ionic liquids or aqueous-ionic liquid biphasic systems. Up to date, there have been many reports on enzyme-exhibited features and enzyme-mediated reactions in ionic liquids. In many cases, remarkable results with respect to yield, catalytic activity, stability and (enantio-, regio-) selectivity were obtained in ionic liquids in comparison with those observed in conventional media. Accordingly, ionic liquids provide new possibilities for the application of new type of solvent in biocatalytic reactions.
基金supported by the National Natural Science Foundation of China (Nos. 41991332, 41977323 and 42090063)。
文摘Paddy soils are potential hotspots of combined contamination with arsenic(As) and antibiotics, which may induce co-selection of antibiotic resistance genes(ARGs) and As biotransformation genes (ABGs), resulting in dissemination of antimicrobial resistance and modification in As biogeochemical cycling. So far, little information is available for these coselection processes and specific patterns between ABGs and ARGs in paddy soils. Here, the16S rRNA amplicon sequencing and high-throughput quantitative PCR and network analysis were employed to investigate the dynamic response of ABGs and ARGs to As stress and manure application. The results showed that As stress increased the abundance of ARGs and mobile genetic elements (MGEs), resulting in dissemination risk of antimicrobial resistance. Manure amendment increased the abundance of ABGs, enhanced As mobilization and methylation in paddy soil, posing risk to food safety. The frequency of the co-occurrence between ABGs and ARGs, the host bacteria carrying both ARGs and ABGs were increased by As or manure treatment, and remarkably boosted in soils amended with both As and manure. Multidrug resistance genes were found to have the preference to be co-selected with ABGs, which was one of the dominant co-occurring ARGs in all treatments, and manure amendment increased the frequency of Macrolide-Lincosamide-Streptogramin B resistance(MLSB) to co-occur with ABGs. Bacillus and Clostridium of Firmicutes are the dominant host bacteria carrying both ABGs and ARGs in paddy soils. This study would extend our understanding on the co-selection between genes for antibiotics and metals, also unveil the hidden environmental effects of combined pollution.
基金supported by the Beijing Nova Program(No.2008B2)
文摘A laboratory-scale bioreactor with polyethylene semi-soft packing was constructed and utilized to determine the efficlency of sulfide biotransformation to sulfur under various operating parameters. Sodium sulfide dissolved in tap water was pumped into the bioreactor as sulfide for biological desulfurization. The sulfide, sulfur and sulfate-S in the effluent and the sulfide purged as gas-phase HzS were determined to investigate the effects of operating parameters, such as pH, DO, hydraulic retention time （HRT）, temperature and salinity, on the sulfide oxidation products. The activity of bacteria was highest at pH 7.8-8.2. The maximal sulfide removal load was 7.25 kg/（m^3·day）, with a 322.07 mg/L influent sulfide concentration and 4.80 mg/L DO. The increase of DO value corresponds to a decrease in the sulfur yield. The reactor had the highest sulfide removal load and sulfur yield at 2.55 mg/L DO. HRT had little effect on desulfurization efficiency when the sulfide removal load was kept constant. The most effective desulfurization temperature was 33℃. The sulfide removal load decreased from 2.85 to 0.51 kg/（m^3.day） with increasing salinity from 0.5% to 2.5% （m/m）.
基金supported by the National Natural Scientific Foundation of China(Nos.82074000 and 81903784)the National Key Research and Development Program of China(No.2021YFA1301200)+2 种基金the Hunan Provincial Natural Science Foundation of China(No.2023JJ4971)the Scientific Research Project of Furong Laboratory of Central South University(No.2023SK2083)the Scientific Research Project of Department of Education of Hunan Province(No.20K136).
文摘Many natural products can be bio-converted by the gut microbiota to influence pertinent efficiency.Ginsenoside compound K(GCK)is a potential anti-type 2 diabetes(T2D)saponin,which is mainly bio-transformed into protopanaxadiol(PPD)by the gut microbiota.Studies have shown that the gut microbiota between diabetic patients and healthy subjects are significantly different.Herein,we aimed to characterize the biotransformation of GCK mediated by the gut microbiota from diabetic patients and healthy subjects.Based on 16S rRNA gene sequencing,the results indicated the bacterial profiles were considerably different between the two groups,especially Alistipes and Parabacteroides that increased in healthy subjects.The quantitative analysis of GCK and PPD showed that gut microbiota from the diabetic patients metabolized GCK slower than healthy subjects through liquid chromatography tandem mass spectrometry(LC-MS/MS).The selected strain A.finegoldi and P.merdae exhibited a different metabolic capability of GCK.In conclusion,the different biotransformation capacity for GCK may impact its anti-diabetic potency.
基金This work is supported by the National Natural Science Foundation of China(to Jungui Dai,No.30100230).
文摘Deacetoxy-13-oxo sinenxan A (1) was converted to 9a-hydroxy-13-oxo-2a, 5a, 10b-triacetoxy-4(20),11-taxadiene (2) and 10b-hydroxy-13-oxo-2a,5a,9a-triacetoxy- 4(20), 11- taxadiene (3) by Ginkgo cell suspension cultures in 45% and 15% yields, respectively.
基金supported by the National Key Research and Development Program of China(Nos.2018YFA0903200 and 2018YFA0903201)the National Natural Science Foundation of China(Nos.81925037 and 31900284)+3 种基金the Chang Jiang Scholars Program(Young Scholar)from the Ministry of Education of China(GAO Hao,2017)the National High-level Personnel of Special Support Program(No.2017RA2259)the Local Innovative and Research Teams Project of Guangdong Pearl River Talents Program(No.2017BT01Y036)K.C.Wong Education Foundation(GAO Hao,2016)。
文摘Biotransformation ofα-asarone by Alternaria longipes CGMCC 3.2875 yielded two pairs of new neolignans,(+)(7 S,8 S,7’S,8’R)iso-magnosalicin(1 a)/(-)(7 R,8 R,7’R,8’S)iso-magnosalicin(1 b)and(+)(7 R,8 R,7’S,8’R)magnosalicin(2 a)/(-)(7 S,8 S,7’R,8’S)magnosalicin(2 b),and four known metabolites,(±)acoraminol A(3),(±)acoraminol B(4),asaraldehyde(5),and 2,4,5-trimethoxybenzoic acid(6).Their structures,including absolute configurations,were determined by extensive analysis of NMR spectra,X-ray crystallography,and quantum chemical ECD calculations.The cytotoxic activity and Aβ_(42)aggregation inhibitory activity of all the compounds were evaluated.Compound 2 displayed significant anti-Aβ_(42)aggregation activity with an inhibitory rate of 60.81%(the positive control EGCG:69.17%).In addition the biotransformation pathway ofα-asarone by Alternaria longipes CGMCC 3.2875 was proposed.
