Medicinal used plants from lndia : analysis of the essential oil of air-dried Biophvtum sensitivum ( L . ) DC

The essential oil of the air-dried plant Biophytum sensitivum (L.) DC. (Oxalidaceae) from Southern lndia was investigated by gas chromatographicspectroscopic (GC-FID and GC-MS) and olfactoric methods to identify compounds responsible for the characteristic odor as well as partly for the folk medicinal use of this plant. Especially benzene derivatives, such as 1,4dimethoxy benzene (24.9%), 1,2-dimethoxy benzene (10.6%) and 2-methoxy4-methyl phenol (3.5%), the monoterpenes (Z)-linalool oxide (8.1 %), (E)linalool oxide (5.2%) and linalyl acetate (3.4%) as well as l-octen-3-01 (9.5%) and isophorone (3.1 %) were found to be main constituents (concentrations higher than 3%, calculated as relative %-peak area of GC-FID analysis using an apolar column) of this essential oil, with totally 69 compounds identified. In addition, the odor impression of the sample is described and the possible biological activity of single volatiles discussed. Key Word Index Biophytum sensitivum (L.) DC., Oxalidaceae, essential oil, air-dried plant, Indian folk medicine L. J i r o v e t z et al.:


Introduction
Biophytum sensitivum (L.) DC. belongs to the Oxalidaceae family (about 70 species known), native to the tropical areas of South Asia and Africa.B.
sensitivum is an annual herb and used in traditional medicine of especially India, Indo-China, the Malaya Archipelago, Madagascar and Africa for its effects against convulsions, inflammatory tumors, burns, fevers, insomnia, asthma, phthisis and diabetes [I-111.While various solvent extracts were studied for biological active compounds (mainly flavonoids) by many research teams [4-1 I ] , to the best of our knowledge, the essential oil constituents of B. sensitivum air-dried plants from southern lndia could be analyzed for the first time.
In continuation of our scientific work on the analyses of essential oils used in traditional Indian medicine, the aim also of this research project was to identify the volatiles of this essential oil of Biophytum sensitivum and to discuss the constituents responsible for the characteristic aroma impressions, their possible biological effects as well as applications in food-flavoring , perfumery and cosmetics.

Results and discussion
The essential oil of air-dried Biophytum sensitivum plants from Southern lndia was olfactorically evaluated as follows: spicy (direction of clove and fennel), earthy-woody (direction of mushrooms and cedarwood), tobacco-and leather-like, floral (direction of bergamote and lavender), fatty-fruity (hazelnutand coconut-notes) and sweet-creamy (vanilla-note).
A possible use of some main compounds with sweet-creamy-fatty (vanilla-, coconut-and hazelnut-notes), like 1,2-dimethoxy benzene, isophorone and 2methoxy-4-methyl phenol in food flavouring (candies, non-alcoholic beverages and bakeries [15]) is also remarkable, but needs a previous testing of nontoxicity.
For an application of the Biophytum sensitivum sample in perfumery and cometics the complex aroma impression could be of interest for products with some of the odor notes to include (earthy-woody and/or tobacco-leather-like andlor sweet-creamy-fatty), such as deodorants, soaps, perfumes and lotions of any type.
In summary, the essential oil of air-dried plants of Biophytum sensitivum from South-India possess a characteristic pleasant odor, showing benzene derivatives (1,4-dimethoxy benzene, 1,2-dimethoxy benzene and 2-methoxy-4methyl phenol), monoterpenes (linalyl acetate, (Z)and (E)-linalool oxide), 1octen-3-01 and isophorone as main compounds.These constituents are especially responsible for the complex odor impression, a possible use as natural drug against different diseases, for the flavoring of various foods as well as aroma-intense agents in some perfumery and cosmetic products.

Experimental Plant Material
The 41).The plants were air-dried for 1 month at room-temperature (22°C) and powdered using an electric grinder.

Essential Oil Extractions
The air-dried and powdered B. sensitivum were steam-distilled using a Clevenger-apparatus for 2.0 hours.The essential oil was extracted with diethyl ether (2 x 100mL) as solvent and dried over anhydrous sodium sulphate.After removal of the sodium sulphate and evaporation of the ether a yield of 0.01g (0.004%) pale yellow-green essential oil was obtained.

Olfactoric Evaluations
The essential oils were diluted with dichloromethane, lop1 placed on a commercial odor-strip and the odor characterized by professional perfumers.

Gas Chromatography
GC analyses were carried out using a Shimadzu GC-14A with FID and the integrator C-R6A-Chromatopac and a Varian GC-3700 with FID and the integrator C-RIB-Chromatopac (Shimadzu Co.).As columns a 30mx0.32mmquantifications by %-peak-area-calculations (unpolar column); Some single components could be identified by co-injection of pure compounds and correlation of their retention-times (using Kovats indices) with published data [22-251.
CSlR New Delhi (B.Jose) as well as the financial support (scholarship for A. Wobus) by the University of Vienna.
of their elution 'concentrations as %-peak-area calculated by GC-FID analysis 3~ovats indices from apolar FSOT-RSL column 4not detected 5 trace compound (less than 0.1%) Tab. 1. Composition of the essential oil (eo) of air-dried plants of Biophytum sensitivum from Southern India The correlation of the olfactoric data with gas chromatographicspectroscopic ones allows the following statement: Eugenol derivatives and I ,4-dimethoxy benzene are especially responsible for the spicy aroma impressions (direction of clove and fennel); earthy-woody odor notes are known from I-octen-3-01 (mushroom-like), isophorone (cedarwood-like) and partly linalool oxides (,,earthy-floral") and tobacco-and leather-like ones from isophorone and 2methoxy-4-methyl phenol.The floral aroma (direction of bergamote and lavender) can be attributed to linalool and its derivatives, such as (2)-and (E)linalool oxide as well as linalyl acetate. 1 ,Cdimethoxy benzene, 1,2-dimethoxy benzene, 2-methoxy-4-methyl phenol, isophorone possess fatty-fruity andlor sweet-creamy odor notes and are therefore responsible for these aroma impressions of the Biophytum sensitivum sample [ I 2-1 61.Referring to the biological activities of identified constituents of the essential oil of air-dried plants of B. sensitivum from South-India the following report can be given: The identified phenolic compounds as well as linalool and its derivatives are known for their antimicrobial effects [17-211.In addition, linalool and its derivatives should be mentioned for their mild sedative and spasmolytic activity [17-211.Therefore, the essential oil of air-dried plants of Biophytum sensitivum fresh plants (250g) of Biophytum sensitivum were collected from the Calicut University campus (Paddy field) in August 2002 and the plant material identified by Dr.A.K. Pradeep, Department of Botany, Calicut University of Kerala.A voucher specimen is deposited in the specially maintained Herbarium of the Department of Chemistry at Calicut University (voucher-no.