Antioxidant and anti-diabetic potential of Passiflora alata Curtis aqueous leaves extract in type 1 diabetes mellitus (NOD-mice)

Leaves of Passiflora alata Curtis were characterized for their antioxidant capacity. Antioxidant analyses of DPPH, FRAP, ABTS, ORAC and phenolic compounds were made in three different extracts: aqueous, methanol/acetone and ethanol. Aqueous extract was found to be the best solvent for recovery of phenolic compounds and antioxidant activity, when compared with methanol/acetone and ethanol. To study the anti-inflammatory properties of this extract in experimental type 1 diabetes, NOD mice were divided into two groups: the P. alata group, treated with aqueous extract of P. alata Curtis, and a non-treated control group, followed by diabetes expression analysis. The consumption of aqueous extract and water ad libitum lasted 28 weeks. The treated-group presented a decrease in diabetes incidence, a low quantity of infiltrative cells in pancreatic islets and increased glutathione in the kidney and liver (p < 0.05), when compared with the diabetic and non-diabetic control-groups. In conclusion, our results suggest that the consumption of aqueous extract of P. alata may be considered a good source of natural antioxidants and compounds found in its composition can act as anti-inflammatory agents, helping in the control of diabetes.     

铁皮石斛叶总黄酮泡腾颗粒剂的制备与抗氧化活性研究

目的 获得铁皮石斛叶黄酮提取物泡腾颗粒剂的制作工艺并测定其抗氧化能力。方法 采取L₉(3⁴)正交设计法,以粒度、溶化时间为评价指标,考察乳糖的用量、柠檬酸与碳酸氢钠的配比、PEG6000的用量对泡腾颗粒剂影响,以最佳处方制备泡腾颗粒剂,并采用《中国药典》2015年版方法对其进行质量评价。采用NaNO2比色法测定制剂中总黄酮的含量。采用DPPH法测定制剂的抗氧化能力。结果 最佳处方为乳糖用量40%,柠檬酸与碳酸氢钠的配比1.3:1,PEG6000用量9%。所得制剂符合《中国药典》2015年版相关标准,其总黄酮含量为(1.29±0.08)mg·g^-1,DPPH清除能力的IC₅₀为(3.77±0.10)mg·mL^-1。结论 本论文将铁皮石斛叶黄酮提取物制备成吸收快、生物利用度高、便于运输携带的泡腾颗粒制剂,该制剂黄酮含量丰富,具有较好的抗氧化能力。     

Mutagenic activity and chemical composition of phenolic-rich extracts of leaves from two species of Ficus medicinal plants

Plant species from the Ficus genus are widely used as food, and in folk medicine as anti-inflammatory, antioxidant and anticancer agents, although some of these species are known to produce adverse effects. The aim of this study was to determine and compare the chemical composition as well as in vitro antioxidant and mutagenic activity of the aqueous extracts of leaves from F. adhatodifolia and F. obtusiuscula. Phytochemical screening using thin-layer chromatography identified 6 classes of secondary metabolites in the extracts. Total phenolic content was estimated by the Folin-Ciocalteau method and the phenolic profile was determined by UPLC-DAD-ESI/MS/MS. Antioxidant activities were evaluated by the DPPH radical assay and by the β-carotene/linoleic acid system. Mutagenic activity was measured by the Salmonella typhimurium reverse mutation test with 4 strains, in both the presence and absence of metabolic activation. Flavonoids, coumarins, and tannins were detected in both extracts, and 6 major derivatives were identified as flavone compounds. Antioxidant activities were demonstrated for both extracts, while F. obtusiuscula contained higher concentrations of phenolic compounds. Mutagenic activity of the TA97 strain without metabolic activation was observed for both tested extracts, as well as the TA102 strain with metabolic activation. In addition, the extract of F. adhatodifolia was shown to be mutagenic to the TA102 strain without metabolic activation. Evidence indicates that the use of teas obtained from these two plant extracts in folk medicine may raise concerns and needs further investigation as a result of potential pro-oxidant mutagenic effects in the absence or presence of metabolic activation.     

罗布麻叶总黄酮类化合物的提取及含量测定

目的建立罗布麻叶总黄酮含量的测定方法,并用此方法优化罗布麻叶的提取方法.方法以槲皮素为标准品,采用紫外分光光度法对罗布麻叶提取物中主要成分黄酮类化合物的含量进行测定,并比较75%乙醇回流、超声、索氏以及水提,超声5种提取方法所得提取物中总黄酮的含量.结果槲皮素的线性范围为2.96-22.20 mg·L-1,回归方程为Y=11.54X+0.175(r=0.999 96),75%乙醇超声2 h所得提取物中黄酮类化合物含量最高(13.07%).结论紫外分光光度法可以作为罗布麻叶的质量控制方法之一,用75%乙醇超声2 h提取所得的提取物中黄酮类化合物的含量较高.     

Antioxidative flavonoids from leaves of Carthamus tinctorius

A total of eight flavonoids (1-8), including a novel quercetin-7-O-(6'-O-acetyl)-beta-D-glucopyranoside (6) and seven known flavonoids, luteolin (1), quercetin (2), luteolin 7-O-beta-D-glucopyranoside (3), luteolin-7-O-(6'-O-acetyl)-beta-D-glucopyranoside (4) quercetin 7-O-beta-D-glucopyranoside (5), acacetin 7-O-beta-D-glucuronide (7) and apigenin-6-C-beta-D-glucopyrano syl-8-C-beta-D-glucopyranoside (8), have been isolated from the leaves of the safflower (Carthamus tinctorius L.) and identified on the basis of spectroscopic and chemical studies. The antioxidative activity of these flavonoids was evaluated against 2-deoxyribose degradation and rat liver microsomal lipid peroxidation induced by hydroxyl radicals generated via a Fenton-type reaction. Among these flavonoids, luteolin-acetyl-glucoside (4) and quercetin-acetyl-glucoside (6) showed potent antioxidative activities against 2-deoxyribose degradation and lipid peroxidation in rat liver microsomes. Luteolin (1), quercetin (2), and their corresponding glycosides (3 & 5) also exhibited strong antioxidative activity, while acacetin glucuronide (7) and apigenin-6,8-di-C-glucoside (8) were relatively less active.     

Xanthine oxidase inhibitory activities of extracts and flavonoids of the leaves of Blumea balsamifera

Context: Blumea balsamifera DC (Compositae) leaves have been recommended for use as a folk medicine in the treatment of various diseases related to urolithiasis in southeast Asia. Phytochemical studies of this plant revealed it contains four classes of flavonoids (e.g., flavonols, flavones, flavanones, and dihydroflavonol derivatives).

Objective: In view of the broad pharmacological activity of flavonoids, this study was carried out to determine the xanthine oxidase (XO) inhibitory and enzymatically produced superoxide radical scavenging activity of different organic extracts and that of the isolated flavonoids from B. balsamifera leaves.

Materials and methods: The inhibitory activity of XO was assayed spectrophotometrically at 295?nm. The superoxide radicals scavenging activity was assessed by NBT reduction method, spectrophotometrically at 560?nm. A dose response curve was plotted for determining IC₅₀ values.

Results: The methanol extract (IC₅₀?=?0.111?mg/mL) showed higher XO inhibitory activity than the chloroform (0.138?mg/mL) and pet-ether extracts (0.516?mg/mL). IC₅₀ values of scavenging of superoxide radicals for extracts decreased in the order of: methanol (0.063?mg/mL)?>?chloroform (0.092?mg/mL)?>?pet-ether (0.321?mg/mL). The XO inhibitory activity of the isolated flavonoids and reference compounds tested decreased in the order of: allopurinol?>?luteolin?>?quercetin?>?tamarixetin?>?5,7,3′,5′-tetrahydroxyflavanone?>?rhamnetin?>?luteolin-7-methyl ether?>?blumeatin?>?dihydroquercetin-4′-methyl ether?>?dihydroquercetin-7,4′-dimethyl ether?>?l-ascorbic acid.

Discussion and conclusion: The results indicated that the flavone derivatives were more active than the flavonol derivatives. The flavanone derivatives were moderately active and the dihydroflavonol derivatives were the least. The higher flavonoid content of extracts contributed to their higher XO inhibitory activity.     

HPLC程序波长法同时测定黄连解毒汤中栀子苷和4种黄酮类成分的含量

目的:建立一种同时检测黄连解毒汤中栀子苷、黄芩苷、汉黄芩苷、黄芩素和汉黄芩素含量的 HPLC 方法。方法:采用Kromasil C_(18)色谱柱(150 mm×4.6 mm,5 μm),以乙腈(A)-5 mmol·L~(-1)磷酸二氢钠溶液(含0.05%磷酸,pH 3.0)(B)为流动相,线性梯度洗脱(0～8.5 min,86.5%B;8.5～17.0 min,86.5%B→80%B;17～30 min,80%B;30～40 min,80%B→60%B;40～51 min,60%B→52%B;51～55 min,52%B→42%B;55～60 min,42%B→86.5%B;60～65 min,86.5%B),流速1.0 mL·min~(-1),程序可变波长紫外检测(0～15 min,238 nm;15～50 min,276 nm)。结果:在58 min 内黄连解毒汤中栀子苷、黄芩苷、汉黄芩苷、黄芩素和汉黄芩素5种成分被完全分离;回归方程显示5种成分的峰面积与其浓度呈良好的线性;5种成分的加样叫收率(n=15)分别为102.2%,97.56%,98.61%,97.85%,98.41%;RSD 小于5.0%。结论:利用程序可变波长检测,建立了一种可靠的同时测定黄连解毒汤中5种标志性成分含量的 HPLC 方法。     

Antioxidative flavonoids from the leaves ofMorus alba

Nine flavonoids (1-9) were isolated from the leaves of Morus alba (Moraceae). The structures of compounds were determined to be kaempferol-3-O-beta-D-glucopyranoside (astragalin, 1) kaempferol-3-O-(6"-O-acetyl)-beta-D-glucopyranoside (2), quercetin-3-O-(6"-O-acetyl)-beta-D-glucopyranoside (3), quercetin-3-O-beta-D-glucopyranoside (4), kaempferol-3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (5), quercetin-3-O-alpha-L-rhamnopyranosyl-(1-->6)-beta-D-glucopyranoside (rutin, 6), quercetin-3-O-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (7), quercetin-3,7-di-O-beta-D-glucopyranoside (8) and quercetin (9) on the basis of spectroscopic and chemical studies. Compounds 7 and 9 exhibited significant radical scavenging effect on 1,1-diphenyl-2-picrylhydrazyl radical.     

Antioxidant activity of extracts and flavonoids from Bidens tripartita

Extracts from herb and flowers of Bidens tripartita L. (Asteraceae), obtained using solvents of different polarity, were studied for their radical scavenging effects. Antioxidant activities of pure flavonoids: flavanomarein (isookanin 7-O-glucoside), cynaroside (luteolin 7-O-glucoside) and luteolin, which had been isolated from this plant, were also evaluated. Radical-scavenging activity was measured by electron paramagnetic resonance (EPR) spectroscopy using stable 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical. The content of flavonoids in flower heads is half of that found in the herb; however, the extract from flowers showed that the antioxidant activity was almost two times higher there. Some extracts (n-BuOH fraction) showed long lasting radical scavenging activity and the EPR spectra were recorded in time to follow the reaction kinetics. Scavenging of DPPH showed second-order kinetics at the beginning of the assay period and later the first-order one. Different kinetics suggested the presence of polymerized and/or less active antioxidants with different scavenging mechanisms for particular polyphenolic compounds. Bur-marigold extracts are a potential source of natural antioxidants that may be used in pharmaceutical or food industry.     

紫外分光光度法测定蒙古黄芪中总黄酮的含量

目的建立黄芪中总黄酮的含量测定方法。方法以芦丁为参照品,利用紫外分光光度法在265nm波长测定总黄酮含量。结果芦丁在8～48μg/ml具有良好的线性关系,回归方程为A=0.03923C-0.01290(r=0.99966),平均回收率为98.14%,RSD=1.21%(n=9)。结论紫外分光光度法简捷、准确、灵敏度高,可用于黄芪药材质量控制。     

LC determination of morphine and morphine glucuronides in human plasma by coulometric and UV detection

A reversed-phase high-performance liquid chromatographic method with coulometric and UV detection has been developed for the simultaneous determination of morphine, morphine-3-glucuronide and morphine-6-glucuronide. The separation was carried out by using a Supelcosil LC-8 DB reversed-phase column and 0.1 M potassium dihydrogen phosphate (pH 2.5)--acetonitrile--methanol (94:5:1 v/v) containing 4 mM pentanesulfonic acid as the mobile phase. The compounds were determined simultaneously by coulometry for morphine and with UV detection for morphine-3-glucuronide and morphine-6-glucuronide. Morphine, morphine glucuronides and the internal standard were extracted from human plasma using Bond-Elut C18 (1 ml) solid-phase extraction cartridges. In the case of coulometric detection, the detection limit was 0.5 ng/ml for morphine; in the case of UV detection the detection limit was 10 ng/ml for morphine-3-glucuronide and for morphine-6-glucuronide, too.     

Cytotoxic chalcones and flavonoids from the leaves of Muntingia calabura

Two new dihydrochalcones, 2',4'-dihydroxy-3'-methoxydihydrochalcone, (-)-3'-methoxy-2',4',beta-trihydroxydihydrochalcone, a new flavanone, (2 S)-(-)-5'-hydroxy-7,3',4'-trimethoxyflavanone, and a new flavonol derivative, muntingone, along with sixteen known compounds, were isolated from the leaves of Muntingia calabura. The structures of these new compounds were determined using spectral analyses including extensive 2D NMR data. Among the isolates, (2 S)-5'-hydroxy-7,3',4'-trimethoxyflavanone, 4'-hydroxy-7-methoxyflavanone, 2',4'-dihydroxychalcone, and 2',4'-dihydroxy-3'-methoxychalcone exhibited cytotoxicity (IC (50) values < 4 microg/mL) against P-388 and/or HT-29 cell lines in vitro.     

Quantitative determination of flavonoids in the flowers and leaves of Prunus spinosa L.

The content of flavonoids in the flowers and leaves of Prunus spinosa L. was determined by spectrophotometric and RP-HPLC method. Determinations included hydrolysis of flavonoid glycosides in extracts from raw materials and then quantitative analysis of the obtained aglycones. Results were calculated for the content of glycosides and statistical analysis of the obtained data was performed.     

紫外分光光度法和高效液相色谱法测定淫羊藿总黄酮含量的比较研究

目的:比较紫外分光光度法和高效液相色谱法测定淫羊藿总黄酮含量的差异,探讨淫羊藿总黄酮含量测定方法的可靠性。方法:紫外分光光度法以淫羊藿苷为指标性成分,在270 nm 波长处进行测定。高效液相色谱法以 ZORBAX SB-C_(18)柱(250mm×4.6 mm,5μm)为分析柱,乙腈-水梯度洗脱,流速1.0 mL·min~(-1),检测波长为270 nm。经紫外光谱识别的黄酮类成分(部分经 ESI-MS 确认),除朝藿定 C、淫羊藿苷、鼠李糖基淫羊藿次苷-Ⅱ和宝藿苷Ⅰ以自身对照外,其他黄酮类成分均以淫羊藿苷为参比进行定量,淫羊藿总黄酮含量等于朝藿定 C、淫羊藿苷、鼠李糖基淫羊藿次苷-Ⅱ、宝藿苷Ⅰ和其他黄酮成分含量之和。结果:紫外分光光度法,淫羊藿苷在2.45～24.50μg·mL~(-1)范围内线性关系良好(r=0.9996),测得淫羊藿总黄酮含量以淫羊藿苷计为56.6%。高效液相色谱法中,与淫羊藿苷紫外光谱相似的33个色谱峰,MS 归属了其中10个主要成分均为黄酮类成分。朝藿定 C、淫羊藿苷、鼠李糖基淫羊藿次苷-Ⅱ和宝藿苷Ⅰ分别在0.093～1.852μg(r=0.9998)、0.107～2.136μg(r=0.9997)、0.094～1.876μg(r=0.9998)、0.098～1.956μg(r=0.9998)线性关系良好,淫羊藿总黄酮含量为35.6%。结论:紫外分光光度法和高效液相色谱法测定的淫羊藿总黄酮含量差异显著,紫外分光光度法的准确性有待进一步考证。     

Antioxidant flavonoids and chlorogenic acid from the leaves ofEriobotrya japonica

The antioxidant activity of Eriobotrya japonica was determined by measuring the radical scavenging effect on DPPH (1,1-diphenyl-2-picrylhydrazyl) radical and lipid peroxidation produced when mouse liver homogenate was exposed to the air at 37 degrees C, using 2-thiobarbituric acid (TBA). The methanol extract and its fractions of Eriobotrya japonica leaves showed strong antioxidant activity. The antioxidant activity of EtOAc and n-BuOH soluble fractions were stronger than the others, and were further purified by repeated silica gel, MCl gel CHP-20P, and Sephadex LH-20 column chromatography. Antioxidant chlorogenic acid, quercetin-3-sambubioside from n-BuOH fraction, and methyl chlorogenate, kaempferol- and quercetin-3-rhamnosides, together with the inactive ursolic acid and 2 alpha-hydroxyursolic acid from EtOAc fraction were isolated. Antioxidant flavonoids and chlorogenic acid also showed prominent inhibitory activity against free radical generation in dichlorofluorescein (DCF) method.