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Telka tree (Pyrus boissieriana Buhse) is growing in north forest of Iran, from beach to mountain. Peduncle, leaf and bark of some genus of Pyrus contain arbutin as phenolglycoside. High quantities of arbutin is found in some plant family such as Saxiferagaceae, Ericaceae, Rosaceae and Compositae. Arbutin is used in treatment of the urinary tract infection and also antioxidant and sunscreen. Arbutin is diuretic and emmenagoge. In this study, antibacterial (Bacillus subtilis), antifungal (Candida albicans and Cladasporium cucumericum), antilarvae (Aedes aegypti), antioxidant and anticholinestrase activities of methanolic and dichloromethane extract of the plant and arbutin performed. Also, arbutin in Telka leaves is determined by HPLC and TLC and quantity has been determined by HPLC and spectrophotometry. Results have been shown that dried extract obtained 4.42% from dichloromethane and 22.04% from methanol, respectively. methanolic extract had antifungal, antioxidant, antilarvae, dichloromethane extract had antibacterial, antioxidant, anticholinestrase, and arbutin had antifungal and antioxidant activities. Arbutin has herbal origin and can be found in leaves of some plants such as Arctostaphylos uva-ursi 4-15%, Vaccinium vitis 5.5-7% and Vaccinium myrtillus 0.4-1.5%. In this study quantity of arbutin in telka was 7.01% and arbutin retention time, relative arbutin retention time in compare with hydroquinone was 5.457, 0.688 respectively. Since there is not A. uva-ursi in Iran, therefore Telka, which contains high quantity of arbutin, also high frequency of this plant is distributed in north of Iran, can be used as good natural source of arbutin.

Phytochemical investigation of the dichloromethane extract of the leaves of Peltophorum pterocarpum, a tropical ornamental tree, led to the isolation of twelve compounds (1-12). One new derivative of peltogynoid ophioglonin (1) and a new 2-phenoxychromone (2) with its 3′-O-β-D-glucoside derivative (3) are described here for the first time. In addition, nine flavonoid derivatives, including peltogynoid ophioglonin (4), were isolated for the first time from this plant. The structures were determined by spectroscopic and chemical methods. Evaluation of the estrogenic activities of 1, 2, and 4 using different model cell systems revealed that 4 was estrogenic and that 2 was largely inactive. Interestingly, 1 was unable to stimulate the proliferation of breast and endometrial cancer cells but exhibited substantial estrogen receptor α-mediated activation of gene expression. This observation indicates that 1 can be further evaluated for its cancer chemopreventive potential. © Georg Thieme Verlag Stuttgart - New York.

International audience; Two new tropane alkaloid N-oxides substituted by a methylpyrrole moiety were isolated from the bark of Erythroxylum vacciniifolium Mart. (Erythroxylaceae), a Brazilian indigenous plant, locally known as catuaba and used in traditional medicine as an aphrodisiac. The alkaloid structures were determined by a combination of high resolution mass spectrometry and multi-dimensional NMR spectroscopy.

Seven coumarins were isolated from the aerial parts of Tordylium apulum; their structures were established by spectroscopic means. All compounds were tested in vitro for their cytotoxicity against two cell line systems. The antiproliferative effects for three of them were studied at the level of the cell cycle in asynchronous cells of the NSCLC-N6 line with a flow cytometry apparatus. Tordylium apoulum L. is an annual herbaceous plant of the Apiaceae family (1) which occurs widely throughout the Mediterranean countries and West Asia. In Greece it is used as a spice with the common name 'kafkalithra'. The composition and antibacterial activity of its essential oil (2) has been previously investigated. A series of antifungal (3) coumarins together with some flavonoids among which is the new natural product quercetin 3-0-(3''',4'''-diacetyl)-α-(L)-rhamnopyranosyl-(1'''- 6''')-β-(D)-glucopyranoside (4) have been also reported. The initial methanolic extract of T. apulum showed an in vitro cytotoxicity activity, IC50 15.6 and 17.4 μg/ml, against the KB and NSCLC-N6 cancer cell lines, respectively. Its bioassay-directed fractionation led to the isolation and identification of seven coumarins: bergaptene (A1), cnidiadin (A2), umbelliferone (A3), R-meranzin (A4), isoimperatorin (A5), 7- prenylumbelliferone (A6) and 2'(S),32'(R)-2'-acetoxyisopropyl-3'-acetoxy- 2',3'-dihydroangelicin (B). Proceeding tothe isolation of the active principles from this extract, the seven isolated coumarins were tested against the same cell lines (Table 1). The antiproliferative effects of the most active ones (A3,A5,b) were studied at the level of the cell cycle in asynchronous cells of the NSCLC-N6 line with a flow cytometry apparatus. A blockade of cells in the G1 phase was demonstrated by a dose-dependent increase in G1 phase and decrease in S and G2M phases in the presence of A3 and A5 after 72 h of culture in comparison with the control. In a histogram in the presence of B at a concentration of 40 μg/ml, in 72 and 96 h of culture, there appeared a similar blockade of cells. It is noteworthy that the antiproliferative effects of the examined compounds on NSCLC-N6 cell line were due to cell blockade in the G1 phase, similar to that produced by inducers of terminal differentiation. The existence of substances capable of inducing irreversible blockade of G1 phase cells suggests that there is a mechanism of action which could provide a new approach to the treatment of slowly developing cancers (5) such as the heterogeneous tested cell line.