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• Simultaneously identified and quantified 18 phenolic compounds from LR fruit by UPLC-Q-Orbitrap MS. • Catechin, naringenin and 9 phenolic acids are the first time to conduct qualitative and quantitative analysis in LR. • Total phenolics content and total anthocyanin content were determined. • The antioxidant activities in vitro of the LR were also evaluated.<br><b>Lycium ruthenicum</b> Murray (LR) is a functional food, and it has long been used in traditional folk medicine. However, detailed qualitative and quantitative analyses related to its phenolic compounds remains scarce. This work reports, for the first time, the establishment of a rapid method for simultaneous identification and quantification of 25 phenolic compounds by UPLC-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS). This method was validated by LODs, LOQs, precision, repeatability, stability, mean recovery, recovery range and RSD. The confirmed method was applied to the analysis of phenolic compounds in LR. Finally, 18 phenolic compounds in LR were qualitatively and quantitatively analyzed. Among them, 11 constituents were detected for the first time, which included two flavonoids (catechin and naringenin) and seven phenolic acids (gallic acid, vanillic acid, 2,4-dihydroxybenzoic acid, veratronic acid, benzoic acid, ellagic acid and salicylic acid). Moreover, Phloretin and protocatechuate, belonging to the dihydrochalcone flavonoid and protocatechuic acid respectively, were also identified and quantified. The total phenolics content (20.17 ± 2.82 mg/g) and the total anthocyanin content (147.43 ± 1.81 mg/g) were determined. In addition, the antioxidant activities of the LR extract were evaluated through 2,2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP) and total antioxidant activity (T-AOC) assays.

Lycium ruthenicum Murray (LR) is a functional food, and it has long been used in traditional folk medicine. However, detailed qualitative and quantitative analyses related to its phenolic compounds remains scarce. This work reports, for the first time, the establishment of a rapid method for simultaneous identification and quantification of 25 phenolic compounds by UPLC-quadrupole-Orbitrap mass spectrometry (UPLC-Q-Orbitrap MS). This method was validated by LODs, LOQs, precision, repeatability, stability, mean recovery, recovery range and RSD. The confirmed method was applied to the analysis of phenolic compounds in LR. Finally, 18 phenolic compounds in LR were qualitatively and quantitatively analyzed. Among them, 11 constituents were detected for the first time, which included two flavonoids (catechin and naringenin) and seven phenolic acids (gallic acid, vanillic acid, 2,4-dihydroxybenzoic acid, veratronic acid, benzoic acid, ellagic acid and salicylic acid). Moreover, Phloretin and protocatechuate, belonging to the dihydrochalcone flavonoid and protocatechuic acid respectively, were also identified and quantified. The total phenolics content (20.17 ± 2.82 mg/g) and the total anthocyanin content (147.43 ± 1.81 mg/g) were determined. In addition, the antioxidant activities of the LR extract were evaluated through 2,2-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity, ferric reducing antioxidant power (FRAP) and total antioxidant activity (T-AOC) assays.

The nanomaterials with enzyme-like catalytic activity, named as nanozymes, have aroused wide research interest owing to their striking merits. Metal-organic frameworks (MOFs) have showed great prospect in the construction of novel nanozymes. In this review, firstly, we summarize the most recent contributions in the design construction of the MOFs-based nanozymes. Then, we concentrate our attention on their applications in the fields of sensing and cancer therapies. According to the design strategies, we categorized MOFs-based nanozymes into four classes for review (i.e. pristine MOFs, MOFs with modification, MOFs-based nanocomposites, and MOF derivatives). Meanwhile, the emerging and fascinating 2D MOFs-based nanozymes were also reviewed. A variety of novel applications are also discussed, including nanozymes catalytic mediated signal amplification in sensing applications (e.g. colorimetric sensing, fluorescent sensing, chemiluminescent sensing, electrochemical sensing, and surface-enhanced Raman scattering (SERS)), and nanozymes catalytic mediated cancer therapy (i.e. cancer-starvation therapy, enhancing photodynamic therapy, and cancer-starvation and PDT synergistic therapy). At the end of the article, future opportunities and challenges in this promising research area are tentatively proposed.

Four U.S. sites formed a consortium to conduct a multisite study of fMRI methods. The primary purpose of this consortium was to examine the reliability and reproducibility of fMRI results. FMRI data were collected on healthy adults during performance of a spatial working memory task at four different institutions. Two sets of data from each institution were made available. First, data from two subjects were made available from each site and were processed and analyzed as a pooled data set. Second, statistical maps from five to eight subjects per site were made available. These images were aligned in stereotactic space and common regions of activation were examined to address the reproducibility of fMRI results when both image acquisition and analysis vary as a function of site. Our grouped and individual data analyses showed reliable patterns of activation in dorsolateral prefrontal cortex and posterior parietal cortex during performance of the working memory task across all four sites. This multisite study, the first of its kind using fMRI data, demonstrates highly consistent findings across sites.
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<i>Saussurea laniceps</i> (Compositae), commonly known as “cotton-headed snow lotus”, is the most effective “snow lotus” used in both Tibetan and Chinese folk medicine. It performs outstandingly in treating rheumatoid arthritis, which mainly is credited for its anti-inflammatory and anti-nociceptive efficacy, as explained by modern pharmacological studies. Extracts of the herb, including umbelliferone and scopoletin, exert such effects in various in vivo and in vitro studies. Besides the two chemicals above, more than 100 organic compounds have been found in <i>S. laniceps</i>, and 58 of them are presented here in molecular structure, including cynaropicrin, mokko lactone, apigenin, acacetin, and luteolin, all contributing to different bioactivities, such as analgesic, antioxidant, immunomodulatory, anti-microbial and anticancer effects. We provide a natural product library of <i>S. laniceps</i>, giving inspirations for structure modification and bioactivity-oriented screening, enabling sustainable use of this valuable plant. The ethnomedical applications and pharmacological discoveries are compared and crosslinked, revealing modern evidence for traditional usages. Despite that <i>S. laniceps</i> is a representative “snow lotus” herb, its material medica records and clinical applications are complicated; there is considerable confusion with the different snow lotuses in the academic community and on the market. This review also aims at clearing such confusion, and improving quality assessment and control of the herb. To better utilize the valuable plant, further comparison among the chemical constitutions, pharmacological activities and therapeutic mechanisms of different snow lotuses are needed.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhodiola crenulata, a traditional Tibetan medicine, has shown promise in the treatment of hypobaric hypoxia (HH)-induced brain injury. However, the underlying mechanisms remain unclear. This study investigated the protective effects of R. crenulata aqueous extract (RCAE) on HH-induced brain injury in rats.MATERIALS AND METHODS: An animal model of high-altitude hypoxic brain injury was established in SD rats using an animal decompression chamber for 24 h. Serum and hippocampus levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG), and lactate dehydrogenase (LDH) were then determined using commercial biochemical kits. Neuron morphology and vitality were also evaluated using H&E and Nissl staining, and TUNEL staining was used to examine apoptosis. Gene and protein expression of HIF-1α, microRNA 210, ISCU1/2, COX10, Apaf-1, cleaved Caspase-3, Caspase-3, Bax, Bcl-2, and Cyto-c were determined by western blot, immunohistochemical and qRT-PCR analysis. RESULTS: RCAE administration attenuated HH-induced brain injury as evidenced by decreased levels of MDA, LDH, and GSSG, increased GSH and SOD, improvements in hippocampus histopathological changes, increased cell vitality and ATP level, and reduced apoptotic cell numbers. RCAE treatment also enhanced HIF-1α, ISCU1/2, COX10, and Bcl-2 protein expression, while dramatically inhibiting expression of Apaf-1, Bax, Cyto-c, and cleaved Caspase-3. Treatment also increased gene levels of HIF-1α, microRNA 210, ISCU1/2, and COX10, and decreased Caspase-3 gene production. CONCLUSIONS: RCAE attenuated HH-induced brain injury by regulating apoptosis and mitochondrial energy metabolism via the HIF-1α/microRNA 210/ISCU1/2 (COX10) signaling pathway.

ETHNOPHARMACOLOGICAL RELEVANCE: Rhodiola crenulata, a traditional Tibetan medicine, has shown promise in the treatment of hypobaric hypoxia (HH)-induced brain injury. However, the underlying mechanisms remain unclear. This study investigated the protective effects of R. crenulata aqueous extract (RCAE) on HH-induced brain injury in rats. MATERIALS AND METHODS: An animal model of high-altitude hypoxic brain injury was established in SD rats using an animal decompression chamber for 24 h. Serum and hippocampus levels of superoxide dismutase (SOD), malondialdehyde (MDA), glutathione (GSH), oxidized glutathione (GSSG), and lactate dehydrogenase (LDH) were then determined using commercial biochemical kits. Neuron morphology and vitality were also evaluated using H&E and Nissl staining, and TUNEL staining was used to examine apoptosis. Gene and protein expression of HIF-1α, microRNA 210, ISCU1/2, COX10, Apaf-1, cleaved Caspase-3, Caspase-3, Bax, Bcl-2, and Cyto-c were determined by western blot, immunohistochemical and qRT-PCR analysis. RESULTS: RCAE administration attenuated HH-induced brain injury as evidenced by decreased levels of MDA, LDH, and GSSG, increased GSH and SOD, improvements in hippocampus histopathological changes, increased cell vitality and ATP level, and reduced apoptotic cell numbers. RCAE treatment also enhanced HIF-1α, ISCU1/2, COX10, and Bcl-2 protein expression, while dramatically inhibiting expression of Apaf-1, Bax, Cyto-c, and cleaved Caspase-3. Treatment also increased gene levels of HIF-1α, microRNA 210, ISCU1/2, and COX10, and decreased Caspase-3 gene production. CONCLUSIONS: RCAE attenuated HH-induced brain injury by regulating apoptosis and mitochondrial energy metabolism via the HIF-1α/microRNA 210/ISCU1/2 (COX10) signaling pathway.

Enzyme inhibition based drug screening strategy has been widely employed for new drug discovery. But this strategy faces some challenges in practical application especially for the trace active compound screening from natural products such as the stability of enzyme and the sensitivity of screening approach. Inspired by the above, we for the first time demonstrate the self-assembly of α-glucosidase (GAA) and glucose oxidase (GOx) into one multi-enzymes-inorganic nanoreactor with hierarchical structure (flower shape). The hybrid enzyme nanoreactor enjoys the merits including the character of assembly line, the enhanced enzymatic activity and robust stability. The flower shape of enzyme nanoreactor possessed a bigger specific surface area, facilitating the trace GAA inhibitor detection. Based on the above, we proposed an enzyme nanoreactor mediated plasmonic sensing strategy for anti-diabetic drug screening. First, maltose was chosen as the substrate for GAA and the generated glucose were immediately utilized by GOx to generate H2O2, and finally, H2O2 etched the Ag nanoprism to round nanodiscs, resulting in the blue shift of surface plasmon resonance (SPR) absorption band. With the aid of hybrid enzyme nanoreactor guided SPR, the ultrasensitive screening of GAA inhibitor (i.e. anti-diabetic drug) can be realized with the detection limit of 5nM for acarbose. The proposed approach was successfully utilized for GAA inhibitor screening from natural products. We anticipate that the proposed sensing method may provide new insights and inspirations in the enzyme inhibition based drug discovery and clinical diagnosis.

Oxidative stress is one of the major mechanisms implicated in endotoxin-induced acute lung injury. Seabuckthorn paste (SP), a traditional Tibetan medicine with high content of polyphenols and remarkable antioxidant activity, is commonly used in treating pulmonary diseases. In the present study, the protective effects and possible underlying mechanisms of SP on lipopolysaccharide- (LPS-) induced acute lung injury in mice were investigated. It was found that body weight loss, lung tissue microstructure lesions, transvascular leakage increase, malondialdehyde augmentation, and the reduction of superoxide dismutase and glutathione peroxidase levels caused by LPS challenge were all consistently relieved by SP treatment in a dose-dependent manner. Moreover, accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) in lung nuclei caused by SP treatment was observed. Our study demonstrated that SP can provide significant protection against LPS-induced acute lung injury through maintaining redox homeostasis, and its mechanism involves Nrf2 nuclear translocation and activation.

Oxidative stress is one of the major mechanisms implicated in endotoxin-induced acute lung injury. Seabuckthorn paste (SP), a traditional Tibetan medicine with high content of polyphenols and remarkable antioxidant activity, is commonly used in treating pulmonary diseases. In the present study, the protective effects and possible underlying mechanisms of SP on lipopolysaccharide- (LPS-) induced acute lung injury in mice were investigated. It was found that body weight loss, lung tissue microstructure lesions, transvascular leakage increase, malondialdehyde augmentation, and the reduction of superoxide dismutase and glutathione peroxidase levels caused by LPS challenge were all consistently relieved by SP treatment in a dose-dependent manner. Moreover, accumulation of nuclear factor erythroid 2-related factor 2 (Nrf2) in lung nuclei caused by SP treatment was observed. Our study demonstrated that SP can provide significant protection against LPS-induced acute lung injury through maintaining redox homeostasis, and its mechanism involves Nrf2 nuclear translocation and activation.

A new and sensitive pre-column derivatization method was developed for the analysis of melamine leached from tableware by high performance liquid chromatography (HPLC) with fluorescence detection. The HPLC sensitivity was greatly enhanced by introducing 10-methyl-acridone-2-sulfonyl chloride (MASC) with excellent fluorescence property into the melamine molecule. Meanwhile, derivatization also greatly increased the hydrophobicity of melamine. Therefore, the common reversed phase column can be used for the HPLC analysis of highly hydrophilic melamine. The detection limit obtained by the proposed method was lower than 0.40 μg/L. This is the first time that HPLC with fluorescence detection was applied to the analysis of melamine. The proposed method was successfully applied to the analysis of melamine leached from tableware. The results indicated that the leaching of melamine from tableware was obvious when hot water or milk was added.<br>• HPLC with fluorescence detection was applied to the analysis of melamine for the first time. • Reversed phase HPLC analysis of melamine was achieved with no ion-pair reagents needed. • HPLC sensitivity was greatly enhanced through derivatization.

<b>Caragana korshinskii</b> Kom. (CK), one of afforestation tree species, is widely planted in northwest region of China. To compare the constituents as references for further utilization of CK, <b>C. microphyll</b> Lam. (CM) and <b>C. jubata</b> L. (CJ), been used as traditional Chinese medicine, were taken into consideration. To obtain more information on CK for further utilization, a sensitive and stable pre-column derivatization method for the analysis of fatty acids (FAs) was established using a novel labeling reagent 2-(5H-benzo[a]-carbazol-11(6H)-yl)ethyl hydrazine-carboxylate (BCEHC) by HPLC with fluorescence detector. The derivatives exhibit predominant fluorescence property at excitation and emission wavelengths of 330 nm and 380 nm, respectively. 16 derivatives of FAs including 13 saturated FAs and 3 unsaturated FAs are separated on a reversed-phase column with gradient elution within 30 min. The validation of method indicated that all FAs were given excellent linear responses with good linear coefficient of correlation being equal to or greater than 0.9985. The limits of detection (LODs) at a signal-to-noise ratio of 3 varied from 63.12 to 116.21 ng L−1. The developed method was successfully applied to determine the contents of free FAs (FFAs) in flowers, leaves and bark of CK and the samples were extracted by a green and simple method of gas purge microsyringe extraction. The results show that the contents of linoleic acid and linolenic acid are high in flowers and leaves while the bark is rich in linoleic acid. The total content of FFAs in all parts of CK is higher than that of CM. The distribution of FFAs in plants is obviously different even in the congeneric among different species.

Micellar electrokinetic electrophoresis was employed to determine two active components, gentiopicroside (GE) and swertiamarin (SW) in one Tibetan preparation medicine named shiweilongdankeli, two Tibetan herbal medicines named Gentiana rhodantha and Gentiana kitag and three other Chinese Gentiana medicines named Gentiana scabra, Gentiana rigescens and Gentiana macrophylla. The dissociation constants of gentiopicroside and swertiamarin determined by MEKC were 7.71 and 6.25. The optimum buffer system was 70 mm borate-10 mm sodium dodecylsulfate (SDS) -6% (v/v) ispropanol (pH 9.0). The voltage was 15 kV and detection was at 254 nm. The lower limits of detection (defined as a signal-to-noise ratio of about 3) were approximately 3.86 mg L(-1) for GE and 5.88 mg L(-1) for SW. The relative standard deviation of the migration time and peak area of the GE and SW were 2.33, 2.47 and 1.27, 2.19%, respectively and the recoveries of the two compounds were 96-104% for GE and 92-102% for SW.; Copyright 2003 John Wiley & Sons, Ltd.

A method of using high-speed counter-current chromatography (HSCCC) and semi-preparative reversed-phase liquid chromatography (semi-preparative RPLC) to preparatively separate flavone glucosides and lignan from the crude extracts of <i>Caragana korshinskii</i> has been established for the first time in this study. Five flavone glucosides, including 9 mg of kaempferol 3-O-{β-<i>d</i>-glucopyranosyl(1→2)-[α-<i>l</i>-rhamonopyranosyl(1 → 6)]-β-<i>d</i>-galactopyranoside}, 21 mg of kaempferol 3-O-α-<i>l</i>-rhamnopyranosyl(1→6)-β-<i>d</i>-galactopyranoside-7-O-α-<i>l</i>-rhamnopyranoside, 34 mg of kaempferol 3-O-β-<i>d</i>-galactopyranoside-7-O-α-<i>l</i>-rhamnopyranoside, 27 mg of kaempferol 3-O-β-<i>d</i>-glucopyranosyl-7-O-α-<i>l</i>-rhamnopyranoside, and 14 mg of calycosin 7-O-β-<i>d</i>-glucopyranoside, and one lignan, 16 mg of alangilignoside B, were successfully isolated from 1.8 g of the crude sample through the combination of HSCCC with a two-phase solvent system composed of ethyl acetate-<i>n</i>-butanol-0.5 % formic acid (4:1:5, <i>v/v/v</i>) and semi-preparative RPLC with a mobile phase of methanol-water (20:80, <i>v/v</i>). The purities of the six compounds are all over 95 % as determined by HPLC and the structures are confirmed by the analysis of UV, <sup>1</sup>H-NMR, and <sup>13</sup>C-NMR and compared with published data.

BACKGROUND: This review aims to rate the quality of evidence and the strength of recommendations in high-quality systematic reviews of non-drug therapies. Hypertensive patients who are resistant or non-adherent to antihypertensive drugs may be easier to manage if they choose alternative non-drug therapies for hypertension, based on this review.METHODS: P: Adults (>18 years), except pregnant women, with essential hypertension. I: Cupping, moxibustion, acupuncture, acupoint stimulation, yoga, meditation, tai chi, Qi gong, Chinese massage, massage, spinal manipulation, biofeedback, device-guided breathing therapy, aromatherapy, music therapy, and relaxation approaches. C: 1. No treatment. 2. Sham therapy. 3. Conventional treatment, including antihypertensive drugs and lifestyle modification (e.g., exercise). O: 1. Change in the incidence of cardiovascular death. 2. Change in the incidence of myocardial infarction. 3. Change in the incidence of stroke. 4. Change in blood pressure (BP). 5. Efficacy rate of BP lowering. 6. Adverse effects (review specific). S: Systematic reviews of randomized controlled trials, including meta-analyses and assessments of the methodological quality/risk of bias. INFORMATION SOURCES: Cochrane Database of Systematic Reviews, Database of Abstracts of Reviews of Effects, Cochrane library, PubMed, Web of Science, China National Knowledge Infrastructure, and Chinese Scientific Journal Database were searched. The bibliographies of the included articles were also searched for relevant systematic reviews. GRADE criteria were used to rate the quality of evidence in systematic reviews considering 6 factors, including risk of bias. RESULTS: This review ultimately included 13 systematic reviews of 14 non-drug therapies (acupuncture, wet cupping, Baduanjin, blood letting, auricular acupuncture, music, massage, Qi gong, moxibustion, relaxation therapies, biofeedback, device-guided breathing, yoga and tai chi) based on the inclusion criteria. The quality of evidence was generally low, and weak recommendations were given for most therapies except massage and acupuncture plus antihypertensive drug. Based on the analyzed evidence, massage and acupuncture plus antihypertensive drug could benefit people who want to lower their BP and do not have contraindications for massage and acupuncture plus antihypertensive drug. DISCUSSION/STRENGTH: The GRADE approach makes this review a unique reference for people who are considering the grade of quality of evidence in systematic reviews, the balance of desirable and undesirable consequences and the strength of recommendations to decide which intervention should be used to reduce BP. LIMITATIONS: Many non-drug therapies were excluded due to the low methodological quality of their systematic reviews, and only 14 therapies were evaluated in this review. As no patient-important outcomes were reviewed, surrogate outcomes were used to rate the strength of recommendations. This approach may cause a decrease in evidence quality according to GRADE, but we argue that this is appropriate in the context of this review.

A simple, sensitive and selective method based on one-step fluorescence labeling and ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) was developed for the determination of biogenic amines (BAs) in foodstuff samples by high-performance liquid chromatography (HPLC) with fluorescence detection (FLD). In this work, fluorescence probe 2-(11H-benzo[a]carbazol-11-yl) ethyl carbonochloridate (BCEC-Cl) was applied to label BAs. What followed was the UA-DLLME procedure that was carried out using chloroform and acetone as extraction and disperser solvents, respectively. A response surface methodology (RSM) based on a Box-Behnken design (BBD) was employed to optimize the main parameters affecting the fluorescence labeling and DLLME efficiency. Under the optimal conditions, this method offered low limits of detection (LODs) of 1.1-7.8 ng/mL and limits of quantification (LOQs) of 3.5-26.1 ng/mL. Finally, the method was successfully used for the determination of trace BAs in real samples and exhibited powerful potential in the high-throughput sample screening.

<br>• A DLLME/HPLC-FLD method for triterpenic acid determination was developed. • DLLME was firstly used for preconcentration of triterpenic acids in medicinal herbs. • This method was sensitive and selective for triterpenic acid analysis. • A new derivatization reagent for triterpenic acid has been synthesized.<br>A novel analytical method was developed for simultaneous determination of six triterpenic acids using ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) follow by high-performance liquid chromatography (HPLC) with fluorescence detection. Six triterpenic acids (ursolic acid, oleanolic acid, betulinic acid, maslinic acid, betulonic acid and corosolic acid) were extracted by UA-DLLME using chloroform and acetone as the extraction and disperser solvents, respectively. After the extraction and nitrogen flushing, the extracts were rapidly derivatized with 2-(12,13-dihydro-7H-dibenzo[a,g]carbazol-7-yl)ethyl4-methylbenzenesulfonate. The main experimental parameters affecting extraction efficiency and derivatization yield were investigated and optimized by response surface methodology (RSM) combined with Box-Behnken design (BBD). The limits of detection (LODs) and the limits of quantification (LOQs) were in the range of 0.95-1.36 ng mL−1 and 3.17-4.55 ng mL−1, respectively. Under the optimum conditions, the method has been successfully applied for the analysis of triterpenic acids in six different traditional Chinese medicinal herbs.

A chemometrics-assisted excitation-emission matrix (EEM) fluorescence method is presented for simultaneous determination of umbelliferone and scopoletin in Tibetan medicine Saussurea laniceps (SL) and traditional Chinese medicine Radix angelicae pubescentis (RAP). Using the strategy of combining EEM fluorescence data with second-order calibration method based on the alternating trilinear decomposition (ATLD) algorithm, the simultaneous quantification of umbelliferone and scopoletin in the two different complex systems was achieved successfully, even in the presence of potential interferents. The pretreatment is simple due to the "second-order advantage" and the use of "mathematical separation" instead of awkward "physical or chemical separation". Satisfactory results have been achieved with the limits of detection (LODs) of umbelliferone and scopoletin being 0.06ngmL(-1) and 0.16ngmL(-1), respectively. The average spike recoveries of umbelliferone and scopoletin are 98.8±4.3% and 102.5±3.3%, respectively. Besides, HPLC-DAD method was used to further validate the presented strategy, and t-test indicates that prediction results of the two methods have no significant differences. Satisfactory experimental results imply that our method is fast, low-cost and sensitive when compared with HPLC-DAD method.

• Extracts from <b>Lycium ruthenicum</b> Murr. fruit were obtained by UAE. • Phenolic compounds and antioxidant activities of obtained extracts were simultaneously optimized by RSM. • Optimum parameters: time 30 min, power 100 W, solvent-sample ratio 40 mL/g, ethanol 33%. • The extracts contained phenolic acids, identified and quantified by HPLC.<br><b>Lycium ruthenicum</b> Murr. (LR) is a functional food that plays an important role in anti-oxidation due to its high level of phenolic compounds. This study aims to optimize ultrasound-assisted extraction (UAE) of phenolic compounds and antioxidant activities of obtained extracts from LR using response surface methodology (RSM). A four-factor-three-level Box-Behnken design (BBD) was employed to discuss the following extracting parameters: extraction time (<b>X</b> 1), ultrasonic power (<b>X</b> 2), solvent to sample ratio (<b>X</b> 3) and solvent concentration (<b>X</b> 4). The analysis of variance (ANOVA) results revealed that the solvent to sample ratio had a significant influence on all responses, while the extraction time had no statistically significant effect on phenolic compounds. The optimum values of the combination of phenolic compounds and antioxidant activities were obtained for <b>X</b> 1 = 30 min, <b>X</b> 2 = 100 W, <b>X</b> 3 = 40 mL/g, and <b>X</b> 4 = 33% (v/v). Five phenolic acids, including chlorogenic acid, caffeic acid, syringic acid, <b>p</b>-coumaric acid and ferulic acid, were analyzed by HPLC. Our results indicated that optimization extraction is vital for the quantification of phenolic compounds and antioxidant activity in LR, which may be contributed to large-scale industrial applications and future pharmacological activities research.

Lycium ruthenicum Murr. (LR) is a functional food that plays an important role in anti-oxidation due to its high level of phenolic compounds. This study aims to optimize ultrasound-assisted extraction (UAE) of phenolic compounds and antioxidant activities of obtained extracts from LR using response surface methodology (RSM). A four-factor-three-level Box-Behnken design (BBD) was employed to discuss the following extracting parameters: extraction time (X1), ultrasonic power (X2), solvent to sample ratio (X3) and solvent concentration (X4). The analysis of variance (ANOVA) results revealed that the solvent to sample ratio had a significant influence on all responses, while the extraction time had no statistically significant effect on phenolic compounds. The optimum values of the combination of phenolic compounds and antioxidant activities were obtained for X1=30min, X2=100W, X3=40mL/g, and X4=33% (v/v). Five phenolic acids, including chlorogenic acid, caffeic acid, syringic acid, p-coumaric acid and ferulic acid, were analyzed by HPLC. Our results indicated that optimization extraction is vital for the quantification of phenolic compounds and antioxidant activity in LR, which may be contributed to large-scale industrial applications and future pharmacological activities research.

<i>Gentiana straminea</i> is the famous Tibetan folk medicine thought to cure various diseases. Historically, the Qinghai-Tibetan region has been considered as the geo-authentic production area of “Mahua Jiao,” where large quantities of the medicine are grown. However, there is still little known about the phytochemical constituent spatial variation of this species. In order to find the differences between the main phytochemical constituents of <i>G. straminea</i> and to provide comprehensive information for quality evaluation, four main bioactive compounds (loganic acid, swertiamarin, gentiopicroside and sweroside) were analysed in 26 populations grown in areas with elevations ranging from 2320 to 4720 m across the Qinghai-Tibetan Plateau. The results showed that the four phytochemical constitutes’ concentrations varied greatly in the spatial profiling of the Qinghai-Tibetan region. Throughout the range of distribution of this species, no altitudinal, latitudinal or longitudinal trends have proven to be significant in any of the four constitutes’ concentrations or their summation. Furthermore, hierarchical clustering analysis and statistical tests showed that four populations (Liu0609-18, Liu0609-15, Liu2006-13-9 and Liu0609-22) had total constitute contents that were higher than other populations. The spatial profiling of the four phytochemical constituents suggests that the geo-authentic producing area of this species exists at a few regions within the Qinghai province, which could be attributed to specific environmental or genetic factors.

AIM: Antioxidant activity is one of the important indexes for estimating medicinal value for the traditional Chinese medicine. The aim of this study is to investigate the antioxidant activity of 11 flavonoids mainly revealing luteolin as mother nucleus isolated from Pyrethrum tatsienense. MATERIALS AND METHODS: The antioxidant activity of 11 flavonoids was measured in vitro using the classical 1,1-diphenyl-2-picrylhydrazyl removal method. The percentages of scavenging activity of 11 flavonoids were analyzed by taking the choice of a-tocopherol as positive drugs, and the scavenging activity was plotted against the sample concentration to obtain the IC50 values. RESULTS: Ten flavonoids containing phenolic hydroxyl groups have different levels of antioxidant activity. Antioxidant activity mainly depends on the numbers and the substitutional positions of phenolic hydroxyls in B ring. When C-3', 4' positions in B ring of flavonoids are replaced by hydroxyl groups, the antioxidant activity improved remarkably. Phenolic hydroxyl groups in A ring contribute some to antioxidant activity because of the electrophilic effect of C ring, and the numbers and substitutional positions of methoxyl and glycosyl have a little effect on the antioxidant activity. CONCLUSION: Structure-activity relationships of antioxidant activity about flavonoids isolated from P. tatsienense are concluded, which will be beneficial to deep understanding the pharmacological functions of this Tibetan medicine in vivo from the point of antioxidation.

OBJECTIVE: To study the chemical constituents of Tibetan Madicine Wangla.METHOD: Sepearing the chemical constituents by means of chromatography and identifying their structures on the basis of MS and NMR spectra and TLC with authentic samples. RESULT: Eight compounds were isolated as 4-[(4-hydroxyphenyl) methoxy]benzenemethanol(I), 4,4'-dihydroxydiphenyl methane(II), 4,4'-dihydroxydibenzyl ether(III), gastrodin(IV), 4-hydroxy benzenemethanol(V), 4-hydroxybenz aldehyde(VI), beta-sitosterol(VII) and beta-daucosterol(VIII). CONCLUSION: All the compounds were obtained from genus Coeloglassum for the first time. The compound I is a new natural product.

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