Comparative Cytotoxicity of Artemisinin and Cisplatin and Their Interactions with Chlorogenic Acids in MCF7 Breast Cancer Cells

In parts of Africa and Asia, self‐medication with a hot water infusion of Artemisia annua (Artemisia tea) is a common practice for a number of ailments including malaria and cancer. In our earlier work, such an extract showed better potency than artemisinin alone against both chloroquine‐sensitive and ‐resistant parasites. In this study, in vitro tests of the infusion in MCF7 cells showed high IC₅₀ values (>200 μM ). The combination of artemisinin and 3‐caffeoylquinic acid (3CA), two major components in the extract, was strongly antagonistic and gave a near total loss of cytotoxicity for artemisinin. We observed that the interaction of 3CAs with another cytotoxic compound, cisplatin, showed potentiation of activity by 2.5‐fold. The chelation of cellular iron by 3CA is hypothesized as a possible explanation for the loss of artemisinin activity.     

Dual Bioactivities of Essential Oil Extracted from the Leaves of Artemisia argyi as an Antimelanogenic versus Antioxidant Agent and Chemical Composition Analysis by GC/MS

The study was aimed at investigating the antimelanogenic and antioxidant properties of essential oil when extracted from the leaves of Artemisia argyi, then analyzing the chemical composition of the essential oil. The inhibitory effect of the essential oil on melanogenesis was evaluated by a mushroom tyrosinase activity assay and B16F10 melanoma cell model. The antioxidant capacity of the essential oil was assayed by spectrophotometric analysis, and the volatile chemical composition of the essential oil was analyzed with gas chromatography-mass spectrometry (GC/MS). The results revealed that the essential oil significantly inhibits mushroom tyrosinase activity (IC₅₀ = 19.16 mg/mL), down-regulates B16F10 intracellular tyrosinase activity and decreases the amount of melanin content in a dose-dependent pattern. Furthermore, the essential oil significantly scavenged 2,2-diphenyl-1-picryl-hydrazyl (DPPH) and 2,2′-azino-bis (3-ethylbenzthiazoline- 6-sulphonic acid) ABTS radicals, showed an apparent reduction power as compared with metal-ion chelating activities. The chemicals constituents in the essential oil are ether (23.66%), alcohols (16.72%), sesquiterpenes (15.21%), esters (11.78%), monoterpenes (11.63%), ketones (6.09%), aromatic compounds (5.01%), and account for a 90.10% analysis of its chemical composition. It is predicted that eucalyptol and the other constituents, except for alcohols, in the essential oil may contribute to its antioxidant activities. The results indicated that essential oil extracted from A. argyi leaves decreased melanin production in B16F10 cells and showed potent antioxidant activity. The essential oil can thereby be applied as an inhibitor of melanogenesis and could also act as a natural antioxidant in skin care products.     

Supercritical fluid extraction of wormwood (Artemisia absinthium L.)

The objective of the work was to optimize the extraction of wormwood oil by supercritical fluid extraction (SFE) of growth-controlled plant material. Different extraction conditions, two growth techniques and various crops were tested and the evolution of the extracted oil composition was screened chromatographically. A comparison with conventional techniques such as hydrodistillation (HD) or organic solvent extraction (OSE) was also presented. Particularly, six CO₂ densities ranging from 285.0 kg/m³ to 819.5 kg/m³ were studied in the range of 9.0-18.0 MPa and 40-50 °C. A systematic study was carried out with plant material from 2005, while SFE of 2006, 2008 and aeroponically grown crops was performed for comparative purposes. The effect of ethanol as a modifier of the supercritical fluid extraction was also studied. The major compounds found in the SFE extracts as well as in the HD essential oils were Z-epoxyocimene, chrysanthenol and chrysanthenyl acetate. A model based on mass transfer equations, the Sovová model, was successfully applied to correlate the experimental data.     

Genotoxic potential of aqueous extracts of Artemisia verlotorum on the cell cycle of Allium cepa

Artemisia verlotorum, popularly ‘infalivina’, is a medicinal herb used for respiratory, circulatory and digestive treatments. Antiproliferative and genotoxic effects of A. verlotorum aqueous extracts in three different concentrations (6, 32 and 48 g/L) were evaluated on the Allium cepa cell cycle. Results clearly showed a significant difference using the χ² test (p = 0.05) among treatments with a decrease in the mitotic index as the concentration of the extract increased. Extracts of A. verlotorum proved to be genotoxic and showed antiproliferative potential on the A. cepa cell cycle. This study suggests the use of infusions of A. verloturum for medicinal purposes only after selecting suitable concentrations.     

Influence ofArtemisia princeps var.orientalis components on callus induction and growth

An in vitro study was performed to determine the potential application of tissue culture in determining allelopathic potentialof Artemisia princeps var.Orientalis (wormwood). Aqueous extracts and volatile substances ofA. princeps var.Orientalis were tested to determine their effects on callus induction and growth of several tested species. Extracts of 5%A. princeps var.Orientalis caused some reduction in concentration, induction, and growth of callus, although they looked normal, whereas the expiants of most receptor plants did not develop callus at higher concentration. Lettuce andEclipta prostrata were the most sensitive species, andA. princeps var.Orientalis was affected by its own extracts. The growth of calluses in MS 121 medium treated with essential oil ofA. princeps var.Orientalis was inhibited, and the degree of inhibition was proportional to the concentration of the essential oil.     

樟树和黄花蒿浸提物对菜粉蝶幼虫的生物活性

研究了樟树和黄花蒿的乙醇、氯仿、石油醚浸提物对菜粉蝶幼虫的拒食作用、触杀作用。结果表明黄花蒿乙醇浸提物和樟树石油醚浸提物的活性较好,48 h拒食率分别为72.11%、57.86%;干物质触杀作用的LC50分别为1.232 g/L、1.275 g/L。     

Plant growth regulatory activities of artemisinin and its related compounds

Artemisinin, a sesquiterpene lactone produced in the leaves ofArtemisia annua, was evaluated for its phytotoxicity in mono- and dicotyledonous plants. Artemisinin inhibited seed germination, seedling growth, and root induction in all species tested. The concentration of artemisinin required for 50% inhibition ofLemna minor growth was 5 M. Inhibitory plant responses appeared to require the endoperoxide moiety of this compound since similar chemicals without endoperoxide, deoxyartemisinin, arteannuic acid, and arteannuin B, were less phytotoxic. InL. minor, artemisinin and arteannuic acid caused the leakage of proteins into the growth medium, suggesting the site of activity was at the plant cell membrane.     

超声波辅助提取藜蒿多酚工艺优化及抗氧化活性研究

以藜蒿为原料,采用超声波辅助法提取藜蒿多酚,研究其最佳提取工艺及体外抗氧化活性。结果表明:超声波辅助提取藜蒿多酚的最佳条件为:液固比20:1(mL/g),提取次数2次,乙醇浓度30%(v/v),超声功率200W,提取时间80min,提取温度80℃,在此条件下,多酚得率为1.858%±0.023%。体外抗氧化实验表明:藜蒿多酚粗提液(PAST)的抗氧化能力随多酚浓度的增加而增强,当多酚浓度大于148.80μg/mL时,PAST对DPPH.的清除能力高于BHA而与没食子酸相当;还原能力顺序为:没食子酸>PAST>BHA,在实验浓度范围内,PAST的还原能力相当于BHA的1.24～1.33倍。     

Behaviour of thujone during distillation and possible concentration ranges in pre‐ban absinthe

A discrepancy in the magnitude of thujone concentrations in distilled pre‐ban absinthe has existed until now. Concentrations of 260 mg L^?1 were derived at by theoretical calculations. Tests of authentic pre‐ban absinthes and studies concerning absinthes produced according to historic recipes found concentrations below 10 mg L^?1. In this study, the behaviour of thujone during distillation was studied and a significant discrimination was determined (80% yield in water‐cum‐steam distillation). The thujone concentrations in distilled pre‐ban absinthe were then calculated with regard to the composition of wormwood derived from a literature review. Due to the large deviations of oil content and thujone concentration of wormwood, a typical Absinthe Suisse de Pontarlier from Duplais' 1855 recipe might have contained between zero and a maximum of 76 mg L^?1 of thujone, the average was calculated as 23 mg L^?1 with a standard deviation of 21 mg L^?1. It was proven that the previous calculations overestimated the thujone content of distilled absinthe and the discrepancy was resolved as our new calculations are in good accord with the experimental findings. Copyright © 2007 Society of Chemical Industry