Variations of the Chemical Constituents and Pharmacological Activities of Pelargonium Graveolens Essential Oil from Three Regions in Palestine
ولد علي, نوار حسني
An-Najah National University
Pelargonium graveolens or Pelargonium roseum is a species that originated in Southern Africa and is related to the Geraniaceae family. It grows in the Mediterranean part of Europe starting in the eighteenth century. Pelargonium graveolens essential oils (E.O.) of the three samples were extracted using microwave ultrasonic apparatus. The chemical constituents of P.graveolens E.O samples were analyzed using Gas Chromatography – Mass Spectroscopy. To detect the antioxidant activity of P.graveolens Essential oil samples we have used the method of Inhibition of 2,2-diphenyl-1-picryl hydrazyl (DPPH) radical to screen the three samples E.O. antioxidant activity. We studied the antilipase activity of P.graveolens E.O samples by using porcine pancreatic lipase and the p-nitro phenylbutyrate (PNPH) method. To detect the α-amylase activity we used the 3,5-dinitrosalicylic acid (DNSA) procedure. The broth microdilution test was used to detect the biological activity of Pelargonium graveolens E.O towards six types of bacteria and against Candida albicans. The essential oil product yield range was (0.5 to 1%) (w/w%). The Gas Chromatography-Mass Spectroscopy test presented the high percentages of oxygenated components in the range of (86.2-88.5%), and non-oxygenated components in the range of (11.5%-13.8%). Twenty-six components were observed, R-Citronellol was the most abundant component in the three samples in the range of (74.4-86%), Citronellyl Formate was the second abundant component with the range of (3.2-14.4%). The sample from Nablus was the potent antioxidant and antiamylase agent with IC50 146.14 and IC50 199.6 µg/ml, respectively. Ramallah's sample (middle region) was the potent antilipase agent with IC50 584.112 µg/mL. The three samples exhibited broad antimicrobial activity; and showed potent antifungal activity with minimum inhibitory concentration (M.I.C.) of 0.3125µg/mL. The sample from Hebron (Southern region) showed the highest potency against ″Methicillin‶ Resistant Staphylococcus Areus (MRSA) with the lowest reported M.I.C. value (0.3125µg/mL) meanwhile the M.I.C. value from Ramallah reached 12.5µg/mL. The study appeared that Pelargonium graveolens E.O. samples from different governorates in Palestine contained different percentages of chemical constituents, which explained the different potential biological activities such as antioxidant, antiobesity, antidiabetic, and antimicrobial activities due to their chemical components. These variations of chemical components are percentages due to the differences in the climate and rainfall average also type of the soil, the old of the plant, and the cultivation season in the different governorates. In Hebron which is sited in the south part of Palestine, the climate is cold in winter and there is significant rainfall throughout the year also it is a height above sea level from 860m-1008m while Ramallah governorate which sited in the middle of Palestine also is weather so cold in winter and there is heavy rainfall during winter but the rate is less than rainfall in Hebron and it is the height above the sea level is 760m-885m. Nablus governorate which is sited in the north part of Palestine also its climate is cold in winter and its rainfall average is moderate its height level above the sea is 430 m -931 m. More in vivo studies are recommended to check out the E.O.'s clinical efficacy and determine the oil's proper clinical uses. It is also recommended to separate the oil's main active ingredients and check out the toxicity of active ingredients, in addition, studying P.graveolens E.O as a food and a medicine flavoring agent, and a preservative.