OBJECTIVETo study the chemical changes of salvianolic acid B and lithospermic acid of Salvia miltiorrhiza under the conditions of high temperature and high pressure and explore the reaction mechanism.

METHODS. miltiorrhiza extracts, salvianolic acid B and lithospermic acid were put in the reactor under the conditions of high temperature and high pressure (120 degrees C, 0.2 MPa), and the chemical changes and stability was studied.

RESULTSalvianolic acid A was the primary product in salvianolic acid B and lithospermic acid's conversion process, and lithospermic acid was an intermediate in the conversion process of salvianolic acid B. Compared with salvianolic acid B, lithospermic acid could convert into more salvianolic acid A and fewer other products in the same conditions. Salvianolic acid A was not stable under the conditions of high temperature and high pressure, and could sequentially convert into other small molecules.

CONCLUSIONReferring to the chemical conversion of salvianolic acid B and lithospermic acid, a method of large-scale preparation of salvianolic acid A can be developed.

Benzofurans ; analysis ; Caffeic Acids ; analysis ; Depsides ; analysis ; Hot Temperature ; Lactates ; analysis ; Pressure ; Salvia miltiorrhiza ; chemistry

OBJECTIVETo investigate the chemical constituents of Ehretia thyrsiflora.

METHODCompounds were isolated with silica gel, Sephadex LH-20 and RP-C18 colum chromatography. Their structures were elucidated by means of physico-chemical properties and spectral analysis.

RESULTSix compounds were isolated and identified as beta-sitosterol (1), ethyl caffeate (2), 2-methoxyl benzoic acid octyl ester (3), tetradecenoic acid, 2,3-dihydroxypropyl ester (4), daucoster (5), allantoin (6).

CONCLUSIONCompounds 1-5 were obtained from this species for the first time. Compounds 2-5 were obtained from the genus Ehretia for the first time.

Allantoin ; chemistry ; Boraginaceae ; chemistry ; Caffeic Acids ; chemistry ; Magnetic Resonance Spectroscopy ; Plant Leaves ; chemistry ; Sitosterols ; chemistry

OBJECTIVETo establish a method for determining the content of caffeic acid in compound Yinhuangjiedu decoction using high-performance capillary electrophoresis (HPCE).

METHODSThe optimized HPCE for determining caffeic acid content utilized a fused-silica capillary tube (75 microm x 60 cm, effective length of 53 cm) with 20 mmol/L borate as the running buffer (pH=9.18), a constant voltage of 12 kV, a sampling time of 5 s at 25 degrees celsius, and UV detection wavelength at 313 nm.

RESULTSThe linear range of caffeic acid was 20-100 microg/ml.

CONCLUSIONHPCE is simple, rapid, and sensitive for quality control of the compound Yinhuangjiedu decoction.

Caffeic Acids ; analysis ; Drugs, Chinese Herbal ; chemistry ; Electrophoresis, Capillary ; methods ; Medicine, Chinese Traditional

The degradation kinetics of chlorogenic acid (5-CQA), cryptochlorogenic acid (4-CQA), and neochlorogenic acid (3-CQA) in aqueous solution at 37 degrees C and different pH values (7.05, 7.96, 9.25) were investigated in the present work. The results indicated that 3-, 4- and 5-CQA tended to remain stable in acidic pH circumstance, and unstable in neutral and alkaline pH circumstance. With the increase of the alkalinity, the degradation of 3-, 4- and 5-CQA was increased leading to a less amount of total CQA and was satisfactorily described by the Weibull equation. Meanwhile, caffeic acid was not detected after the degradation of CQA. Moreover, the degradation of 3-CQA and 5-CQA tended to be converted to 4-CQA, and the degradation of 4-CQA tended to be converted to 3-CQA rather than 5-CQA. The comparison of the degradation kinetics parameters of 3-, 4- and 5-CQA at neutral and alkaline pH values showed that the orders of the rate constant (k) values were 4-CQA > 3-CQA > 5-CQA, while the orders of the degradation half life (t½) values were 4-CQA < 3-CQA < 5-CQA, indicating the orders of the stabilities of 3-, 4- and 5-CQA at 37 degrees C and neutral and alkaline pH values were 4-CQA < 3-CQA < 5-CQA.
Caffeic Acids ; Chlorogenic Acid ; analogs & derivatives ; chemistry ; Hydrogen-Ion Concentration ; Kinetics

Caffeic acid and its oligomers are the main water-soluble active constituents of the traditional Chinese medicine(TCM) Arnebiae Radix. These compounds possess multiple biological activities such as antimicrobial, antioxidant, cardiovascular protective, liver protective, anti-liver fibrosis, antiviral and anticancer activities. The phenylpropanoid pathway in plants is responsible for the biosynthesis of caffeic acid and its oligomers. Glycosylation can change phenylpropanoid solubility, stability and toxic potential, as well as influencing compartmentalization and biological activity. In view of the important role played by de-glycosylation in the regulation of phenylpropanoid homeostasis, the biosynthesis of caffeic acid and its oligomers are supposed to be under the control of relative UDP-glycosyltransferases(UGTs). Through the data mining of Arnebia euchroma transcriptome, we cloned 15 full-length putative UGT genes. After recombinant expression using the prokaryotic system, the crude enzyme solution of the putative UGTs was examined for the glycosylation activities towards caffeic acid and rosmarinic acid in vitro. AeUGT_01, AeUGT_02, AeUGT_03, AeUGT_04 and AeUGT_10 were able to glycosylate caffeic acid and/or rosmarinic acid resulting in different mono-and/or di-glycosylated products in the UPLC-MS analyses. The characterized UGTs were distantly related to each other and divided into different clades of the phylogenetic tree. Based on the observation that each characterized UGT exhibited substrate or catalytic similarity with the members in their own clade, we supposed the glycosylation abilities towards caffeic acid and/or rosmarinic acid were evolved independently in different clades. The identification of caffeic acid and rosmarinic acid UGTs from A. euchroma could lead to deeper understanding of the caffeic acid oligomers biosynthesis and its regulation. Furthermore, these UGTs might be used for regiospecific glycosylation of caffeic acid and rosmarinic acid to produce bioactive compounds for potential therapeutic applications.
Boraginaceae/genetics* ; Caffeic Acids ; Chromatography, Liquid ; Cinnamates ; Cloning, Molecular ; Depsides ; Glycosyltransferases/genetics* ; Phylogeny ; Tandem Mass Spectrometry

The metabolites of salvianolic acid A and salvianolic acid B in rats were analyzed and compared by ultra-high-perfor-mance liquid chromatography with linear ion trap-orbitrap mass spectrometry(UHPLC-LTQ-Orbitrap MS). After the rats were administrated by gavage, plasma at different time points and urine within 24 hours were collected to be treated by solid phase extraction(SPE), then they were gradient eluted by Acquity UPLC BEH C_(18) column(2.1 mm×100 mm, 1.7 μm) and 0.1% formic acid solution(A)-acetonitrile(B) mobile phase system, and finally all biological samples of rats were analyzed under negative ion scanning mode. By obtaining the accurate relative molecular mass and multi-level mass spectrometry information of metabolites, combined with the characteristic cleavage law of the reference standard and literature reports, a total of 30 metabolites, including salvianolic acid A and B, were identified. Among them, there were 24 metabolites derived from salvianolic acid A, with the main metabolic pathways including ester bond cleavage, dehydroxylation, decarboxylation, hydrogenation, methylation, hydroxylation, sulfonation, glucuronidation, and their multiple reactions. There were 15 metabolites of salvianolic acid B, and the main biotransformation pathways were five-membered ring cracking, ester bond cleavage, decarboxylation, dehydroxylation, hydrogenation, methylation, sulfonation, glucuronidation, and their compound reactions. In this study, the cross-metabolic profile of salvianolic acid A and B was elucidated completely, which would provide reference for further studies on the basis of pharmacodynamic substances and the exploration of pharmacological mechanism.
Animals ; Benzofurans ; Caffeic Acids ; Chromatography, High Pressure Liquid ; Lactates ; Mass Spectrometry ; Rats ; Technology

Although various derivatives of caffeic acid have been reported to possess a wide variety of biological activities such as protection of neuronal cells against excitotoxicity, the biological activity of 1-docosanoyl cafferate (DC) has not been examined. The objective of the present study was to evaluate the anti-inflammatory effects of DC, isolated from the stem bark of Rhus verniciflua, on lipopolysaccharide (LPS)-stimulated BV2 microglial cells. Pretreatment of cells with DC significantly attenuated LPS-induced NO production, and mRNA and protein expression of iNOS in a concentration-dependent manner. DC also significantly suppressed LPS-induced release of cytokines such as TNF-alpha and IL-1beta . Consistent with the decrease in cytokine release, DC dose-dependently and significantly attenuated LPS-induced mRNA expression of these cytokines. Furthermore, DC significantly suppressed LPS-induced degradation of IKB, which retains NF-kB in the cytoplasm. Therefore, nuclear translocation of NF-kB induced by LPS stimulation was significantly suppressed with DC pretreatment. Taken together, the present study suggests that DC exerts its anti-inflammatory activity through the suppression of NF-kB translocation to the nucleus.
Caffeic Acids ; Cytokines ; Cytoplasm ; Neurons ; NF-kappa B ; Rhus ; RNA, Messenger ; Tumor Necrosis Factor-alpha

The 4-hydroxyphenylacetate 3-hydroxylase (4HPA3H), originated from Escherichia coli, converts p-coumaric acid to caffeic acid. In order to improve the efficiency of caffeic acid biosynthesis, we engineered E. coli for overexpression of 4HPA3H. The high-density fermentation of the engineered E. coli was conducted in a 5 L bioreactor. Subsequently, the conditions for whole-cell biocatalysis were optimized. The dry cell weight of the 4HPA3H-expressed strain reached 34.80 g/L. After incubated in the bioreactor for 6 h, 18.74 g/L (0.85 g/(L·OD₆₀₀)) of caffeic acid was obtained, with a conversion rate of 78.81% achieved. To the best of our knowledge, the titer of caffeic acid is the highest reported to date. The high-density fermentation of E. coli for overexpression of 4HPA3H and the efficient biosynthesis of caffeic acid may facilitate future large-scale production of caffeic acid.
Caffeic Acids ; Escherichia coli/metabolism* ; Fermentation ; Metabolic Engineering ; Mixed Function Oxygenases/metabolism* ; Phenylacetates

OBJECTIVETo investigate the absolute bioavailability of caffeic acid in rats and its intestinal absorption properties.

METHODThe absolute bioavailability (Fabs) of caffeic acid was obtained after iv (2 mg x kg(-1)) or ig (10 mg x kg(-1)) administration to rats. The intestinal absorption of caffeic acid was explored by the recirculating vascularly perfused rat intestinal preparation. Caco-2 cell model was applied to measure the permeability of caffeic acid from apical to basolateral said (A-B) and from basolateral to apical said (B-A).

RESULTA two-compartment pharmacokinetic model was best to describe the pharmacokinetics of caffeic acid following iv or ig administration. The Fabs of caffeic acid was 14. 7% , and its intestinal absorption was 12.4%. The values of Papp A-->B and Papp B-->A of caffeic acid were retained stable while its concentration was changed. The efflux ratio values in this study surveyed were above 2.0, and suggesting caffeic acid was active transport.

CONCLUSIONCaffeic acid was shown to have poor permeability across the Caco-2 cells, low intestinal absorption and low oral bioavailability in rats.

Animals ; Biological Availability ; Caco-2 Cells ; Caffeic Acids ; metabolism ; pharmacokinetics ; Humans ; Intestinal Absorption ; Male ; Rats ; Rats, Sprague-Dawley

Taking application of some isolation and purification technologies, such as solvent extraction, preliminary solvent isolation, column chromatographies over silica gel and Sephadex LH-20 gel and preparative HPLC, 10 compounds were obtained from Gynura nepalensis cultivated in the suburban area of Beijing. Their structures were identified by spectroscopic methods and comparison with literature as (3R) -3-hydroxy-β-ionone (1), (3S,5R, 6S, 7E) -5, 6-epoxy-3-hydroxy-7-megastigmen-9-one (2), (+) -boscialin (3), 3, 6-trans-3-hydroxy-α-ionone (4), 3, 6-cis-3-hydroxy-α-ionone (5), 3, 4-cis-3, 4-dihydroxy-β-ionone (6), ethyl caffeate (7), loliolide (8), 1H-indole-3-carbaldehyde (9), and 3-(hydroxyacetyl)indole (10), respectively. All compounds were isolated from the title plant for the first time, and with compounds 1, 2, 4-7, 9 and 10 being isolated from Gynura species for the first time. Structurally, the above compounds 1-6 belong to C13 nor-sesquiterpenoids, sharing the same carbon skeleton of megastigmane. According to this study, they are one of major kinds of chemical constituents of Gynura nepalensis and have important reference value for the investigation on phytotaxonomy of this species.
Asteraceae ; chemistry ; Caffeic Acids ; chemistry ; Cyclohexanones ; Drugs, Chinese Herbal ; chemistry ; Glucosides ; Indoles ; chemistry ; Mass Spectrometry ; Molecular Structure ; Norisoprenoids ; chemistry