OBJECTIVETo study the chemical constituents of the corm of the planted Cremastra appendiculata.

METHODThe compounds were isolated by column chromatography with silica gel and Sephadex LH-20, and their structures were elucidated by means of spectroscopic methods including 2D NMR techniques.

RESULTSix compounds were isolated, and identified as isohircinol (I), flavanthrinin (II), p-hydroxyphenylethyl alcohol (III), 3,4-dihydroxyphenylethyl alcohol (IV), daucosterol (V), beta-sitosterol (VI).

CONCLUSIONThese compounds were not previously isolated from this plant, and isohircinol (I) was obtained from natural source for the first time.

Orchidaceae ; chemistry ; Phenylethyl Alcohol ; analogs & derivatives ; chemistry ; isolation & purification ; Plants, Medicinal ; chemistry ; Sitosterols ; chemistry ; isolation & purification

Hydroxytyrosol is an important fine chemical and is widely used in food and medicine as a natural antioxidant. Production of hydroxytyrosol through synthetic biology is of important significance. Here we cloned and functionally characterized a hydroxylase encoding gene HpaBC from Escherichia coli BL21, and both subunits of this enzyme can be successfully expressed to convert the tyrosol into hydroxytyrosol. A HpaBC gene integration expression cassette under the tac promoter was constructed, and integrated into the genome of a tyrosol hyper-producing E. coli YMG5A*R using CRISPR-Cas9 technology. Meanwhile, the pathway for production of acetic acid was deleted, resulting in a recombinant strain YMGRD1H1. Shake flask fermentation showed that strain YMGRD1H1 can directly use glucose to produce hydroxytyrosol, reaching a titer of 1.81 g/L, and nearly no by-products were detected. A titer of 2.95 g/L was achieved in a fed-batch fermentation conducted in a 5 L fermenter, which is the highest titer for the de novo synthesis of hydroxytyrosol from glucose reported to date. Production of hydroxytyrosol by engineered E. coli lays a foundation for further construction of hydroxytyrosol cell factories with industrial application potential, adding another example for microbial manufacturing of aromatic compounds.
Escherichia coli/genetics* ; Fermentation ; Glucose ; Metabolic Engineering ; Phenylethyl Alcohol/analogs & derivatives*

Salidroside, the 8-O-beta-D-glucoside of tyrosol, is a novel adaptogenic drug extracted from the medicinal plant Rhodiola sachalinensis A. Bor. Due to the scarcity of R. sachalinensis and its low yield of salidroside, there is great interest in enhancing the production of salidroside by biotechnological process. Glucosylation of tyrosol is thought to be the final step in salidroside biosynthesis. In our related works, three UGT clones were isolated from the roots and the cultured cells. Our intention was to combine the catalytic specificity of these UGTs in vitro in order to change the level of salidroside in vivo by over-expression of the above UGTs. However, as the aglycone substrate of salidroside, the biosynthetic pathway of tyrosol and its regulation are less well understood. The results of related studies revealed that there are two different possibilities for the tyrosol biosynthetic pathway. One possibility is that tyrosol is produced from a p-coumaric acid precursor, which is derived mainly from phenylalanine. The second possibility is that the precursor of tyrosol might be tyramine, which is synthesized from tyrosine. Our previous work demonstrated that over-expression of the endogenous phenylalanine ammonia-lyase gene (PALrs1) and accumulation of p-coumaric acid did not facilitate tyrosol biosynthesis. In contrast, the data presented in our recent work provide in vitro and in vivo evidence that the tyrosine decarboxylase (RsTyrDC) is most likely to have an important function in the initial reaction of the salidroside biosynthesis pathway in R. Sachalinensis.
Genetic Engineering ; Glucosides ; biosynthesis ; Glycosylation ; Phenols ; Phenylethyl Alcohol ; analogs & derivatives ; chemistry ; metabolism ; Rhodiola ; metabolism ; Tyrosine ; metabolism ; Tyrosine Decarboxylase ; metabolism

OBJECTIVETo assay salidroside and p-tyrosol in Hongjingtian for injection (freezing-dry).

METHODSamples were purified by Sep-Pak C18 column and salidroside and p-tyrosol were determined by HPLC with Irregular-H C18 (4.6 mm x 250 mm, 5 microm), and eluted with a mobile phase of methanol-acenitonitrile -0.06% phosphate (10: 10:80). The flow rate was 1.0 mL x min(-1), the detection wavelength was set at 275 nm and the column temperature was maintained at 30 degrees C.

RESULTThe calibration curves were linear in the range of 2.24-22.4 microg for salidroside (0.999 7) and 0.856-8.56 microg for p-tyrosol (0.999 6), the average recovery was 101.3%, 99.8% respectively.

CONCLUSIONThe method is convenient, rapid, accurate and reliable.

Chromatography, High Pressure Liquid ; methods ; Drugs, Chinese Herbal ; administration & dosage ; chemistry ; Glucosides ; analysis ; Injections ; Phenols ; analysis ; Phenylethyl Alcohol ; analogs & derivatives ; analysis ; Plants, Medicinal ; chemistry ; Rhodiola ; chemistry ; Temperature

BACKGROUNDOsteoporosis (OP) is a common bone disease, which adversely affects life quality. Effective treatments are necessary to combat both the loss and fracture of bone. Recent studies indicated that caffeic acid phenethyl ester (CAPE) is a natural chemical compound from honeybee propolis which is capable of attenuating osteoclastogenesis and bone resorption. Therefore, this study aimed to investigate the effect of CAPE on bone loss in OP mice using micro-computed tomography (CT) and histology.

METHODSEighteen mice were prepared and evenly divided into three groups. The six mice in the sham+PBS group did not undergo ovariectomy and were intraperitoneally injected with PBS during the curing period. Twelve mice were ovariectomized (OVX) to induce OP. Six of them in the OVX+CAPE group were intraperitoneally injected with 0.5 mg/kg CAPE twice per week for 4 weeks after ovariectomy. The other six OVX mice in OVX+PBS group were treated with PBS. All the mice were sacrificed 4 weeks after ovariectomy. The tibias were bilaterally excised for micro-CT scan and histological analysis. The Mann-Whitney U test was used to test the statistical differences among groups.

RESULTSBone loss occurred in OVX mice. Compared with the sham+PBS group, mice in the OVX+PBS group exhibited a significant decrease in bone mineral density (BMD, P < 0.05), bone volume fraction (BV/TV, P < 0.01), trabecular thickness (Tb.Th, P < 0.05), and trabecular number (Tb.N, P < 0.01), as well as a non-insignificant increase in the number of osteoclasts (N.Oc/B.Pm). With CAPE treatment, the microarchitecture of the tibial metaphyses was significantly improved with a reduction of osteoclast formation. Compared with the OVX+PBS group, BV/TV in the OVX+CAPE group was significantly increased by 33.9% (P < 0.05).

CONCLUSIONCAPE therapy results in the protection of bone loss induced by OVX.

Animals ; Bone Density ; drug effects ; Caffeic Acids ; pharmacology ; Female ; Metabolism ; drug effects ; Mice ; Mice, Inbred C57BL ; Ovariectomy ; Phenylethyl Alcohol ; analogs & derivatives ; pharmacology ; Propolis ; chemistry ; Tomography, X-Ray Computed

OBJECTIVETo study the effects of radiation emitted by mobile phones on bone strength and caffeic acid phenethyl ester (CAPE) on the changes induced by radiation.

METHODSForty-eight Sprague-Dawley rats were divided into five groups. Rats in the control group (first group) were left within the experimental setup for 30 min/day for 28 days without radiation exposure. Nine hundred MHz radiation group was broke down into 2 subgroups (group 1/2). Both subgroups were exposed to radiation for 28 days (30 min/day). The next group was also divided into 2 subgroups (group 3/4). Each was exposed to 1800 MHz of radiation for 28 days (30 min/day). The third and fifth groups were also treated with CAPE for 28 days. Treatment groups received ip caffeic acid phenethyl ester (10 micromol/kg per day) before radiation session. Bone fracture was analyzed.

RESULTSBreaking force, bending strength, and total fracture energy decreased in the irradiated groups but increased in the treatment groups.

CONCLUSIONRadiation and CAPE can significantly improve bone.

Animals ; Biomechanical Phenomena ; Bone Density ; Caffeic Acids ; administration & dosage ; Electromagnetic Fields ; Femur ; pathology ; Fractures, Bone ; prevention & control ; Male ; Phenylethyl Alcohol ; administration & dosage ; analogs & derivatives ; Radiation Injuries, Experimental ; prevention & control ; Radiation-Protective Agents ; administration & dosage ; Rats ; Rats, Sprague-Dawley

Periodontal disease is associated with chronic oxidative stress and inflammation. Caffeic acid phenethyl ester (CAPE), which is a potent inducer of heme oxygenase 1 (HO1), is a central active component of propolis, and the application of propolis improves periodontal status in diabetic patients. Here, primary murine macrophages were exposed to CAPE. Target gene expression was assessed by whole-genome microarray, RT-PCR and Western blotting. The antioxidative and anti-inflammatory activities of CAPE were examined by exposure of the cells to hydrogen peroxide, saliva and periodontal pathogens. The involvement of HO1 was investigated with the HO1 inhibitor tin protoporphyrin (SnPP) and knockout mice for Nrf2, which is a transcription factor for detoxifying enzymes. CAPE increased HO1 and other heat shock proteins in murine macrophages. A p38 MAPK inhibitor and Nrf2 knockout attenuated CAPE-induced HO1 expression in macrophages. CAPE exerted strong antioxidative activity. Additionally, CAPE reduced the inflammatory response to saliva and periodontal pathogens. Blocking HO1 decreased the antioxidative activity and attenuated the anti-inflammatory activity of CAPE. In conclusion, CAPE exerted its antioxidative effects through the Nrf2-mediated HO1 pathway and its anti-inflammatory effects through NF-κB inhibition. However, preclinical models evaluating the use of CAPE in periodontal inflammation are necessary in future studies.
Animals ; Caffeic Acids ; pharmacology ; Heme Oxygenase-1 ; genetics ; metabolism ; Humans ; Inflammation ; drug therapy ; Mice ; NF-kappa B ; antagonists & inhibitors ; genetics ; metabolism ; Oxidative Stress ; drug effects ; Phenylethyl Alcohol ; analogs & derivatives ; pharmacology

Tyrosol, crenulatin and salidroside are the main active constituents of Rhodiola crenulata, with extensive pharmacological activities. In the study, grams of high purity tyrosol, crenulatin and salidroside were simultaneously separated from R. crenulata by the first time. Firstly, R. crenulata was extracted by 70% alcohol. Then, with the yields of three compounds as the index, the macroporous resin was optimized. At last, grams of high purity tyrosol, crenulatin and salidroside were isolated by D-101 macroporousresin, purified by column chromatography. Detected by HPLC, the purity of three compounds were higher than 98%. This method has the advantages of simple process and operation, less dosage of organic solvent, highly yield and reproducibility, suitable for the simultaneously preparation of tyrosol, crenulatin and salidroside.
Chemical Fractionation ; methods ; Chemistry, Pharmaceutical ; Chromatography, High Pressure Liquid ; Coumarins ; analysis ; isolation & purification ; Drugs, Chinese Herbal ; analysis ; isolation & purification ; Glucosides ; analysis ; isolation & purification ; Phenols ; analysis ; isolation & purification ; Phenylethyl Alcohol ; analogs & derivatives ; analysis ; isolation & purification ; Rhodiola ; chemistry

AIMTo show the oxidative stress after cigarette smoke exposure in rat testis and to evaluate the effects of caffeic acid phenethyl ester (CAPE).

METHODSTwenty-one rats were divided into three groups of seven. Animals in Group I were used as control. Rats in Group II were exposed to cigarette smoke only (4 x 30 min/d) and rats in Group III were exposed to cigarette smoke and received daily intraperitoneal injections of CAPE (10 micromol/kg x d). After 60 days all the rats were killed and the levels of nitric oxide (NO) and anti-oxidant enzymes such as superoxide-dismutase, catalase and glutathione peroxidase (GSH-Px) and the level of malondialdehyde were studied in the testicular tissues of rats with spectrophotometric analysis.

RESULTSThere was a significant increase in catalase and superoxide-dismutase activities in Group II when compared to the controls, but the levels of both decreased after CAPE administration in Group III. GSH-Px activity was decreased in Group II but CAPE caused an elevation in GSH-Px activity in Group III. The difference between the levels of GSH-Px in Group I and Group II was significant, but the difference between groups II and III was not significant. Elevation of malondialdehyde after smoke exposure was significant and CAPE caused a decrease to a level which was not statistically different to the control group. A significantly increased level of NO after exposure to smoke was reversed by CAPE administration and the difference between NO levels in groups I and III was statistically insignificant.

CONCLUSIONExposure to cigarette smoke causes changes in the oxidative enzyme levels in rat testis, but CAPE can reverse these harmful effects.

Animals ; Antioxidants ; therapeutic use ; Caffeic Acids ; therapeutic use ; Catalase ; metabolism ; Glutathione Peroxidase ; metabolism ; Male ; Malondialdehyde ; metabolism ; Nitric Oxide ; metabolism ; Oxidative Stress ; physiology ; Phenylethyl Alcohol ; analogs & derivatives ; therapeutic use ; Rats ; Rats, Wistar ; Smoking ; Superoxide Dismutase ; metabolism ; Testis ; drug effects ; physiopathology

OBJECTIVETo investigate the effect of andrographolide (AG) on quroum sensing (QS) and relevant virulence genes of Candida albicans.

METHODGas-chromatography-mass spectrometry (GC-MS) was applied to detect the changes in the content of farnesol and tyrosol in C. albicans intervened by AG. The real-time quantitative PCR (qRT-PCR) was adopted to inspect the expressions of relevant virulence genes such as CHK1, PBS2 and HOG1 regulated by QS.

RESULTAt 2 h after the growth of C. albican, the farnesol and tyrosol secretions reduced, without notable change after intervention with AG. The secretions were highest at 12 h and decreased at 24 h. After the intervention with different concentrations of AG, the farnesol content reduces, whereas tyrosol increased, indicating a dose-dependence, particularly with 1 000 mg x L(-1) AG. qRT-PCR revealed that 1 000 mg x L(-1) AG could down-regulate CHK1 by 2.375, 3.330 and 4.043 times and PBS2 by 2.010, 4.210 and 4.760 times, with no significant change in HOG1.

CONCLUSIONAG could inhibit the farnesol secretion, promote the tyrosol secretion and down-regulate QS-related virulence genes CHK1 and PBS2 expressions.

Candida albicans ; drug effects ; genetics ; physiology ; Diterpenes ; pharmacology ; Farnesol ; analysis ; metabolism ; Gas Chromatography-Mass Spectrometry ; Genes, Fungal ; Phenylethyl Alcohol ; analogs & derivatives ; analysis ; metabolism ; Quorum Sensing ; drug effects ; Real-Time Polymerase Chain Reaction ; Virulence ; genetics