Analysis Of Extractables From Ten Ficus Species In Kenya And Hplc Analysis Of Some Common Fatty Acids As Their P-phenylphenacyl Esters

Abstract

ABSTRACT A screenlng procedure utilizing successive extractions with acetone, cyclohexane and methanol was applied to 10 Ficus specie~ in order to quantify their solvent extractables. The species include Ficus benjamina, F. capensis, F. elastica, F. glumosa, F. ingene, F. ovata F. sansibarica, F. thonningii and F. volgelii, all of which are found ln Kenya at different altitudes and climatic regions. A combined solvent extractionpartitioning scheme was used to divide the dried, ground leaves and stems into oil, polyphenolic, hydrocarbon and sugar-containing fractions, which might be of use as sources of chemical raw materials and renewable, biomassderived fuels. The fractions were examined by IR, UVand NMR spectroscopy, while the xesidues were analysed for protein and crude fibre content. Bomb calorimetric .. study was done to determine the heat of combustion of each fraction. The iodine and saponification numbers, and saponifiable and unsaponifiable matter of the oil fractions were estimated by standard titrimetric methods. The results showed that the amount of extractable oils varied from one species to the other, being highest In F.bC_f-1jE..m~na(5.43%) during the dry season and lowe st in I_'_~_~J)ensis(O.S3~) during the wet season. The oils have a heat value va ry i ng from 39.S6~IJ/Kg to tl3.74i'vlJ/Kg. v The oils also showed reasonably high iodine and saponification numbers of over 90 and 110 respectively. The oils also showed reasonably high content of unsaponifiab1e matter ranging between 23.81% in F. sansibarica and 37.50% in F. benjamina. The quantity of the hydrocarbon fraction extracted varied from 0.21% in F.sycomorus to 3.54% ln F. benjamina during the dry season, and between 0.22% and 1.31% in F. ingene and F. vOlge1ii respectively during the wet season. The heat of combustion of the hydrocarbon fractions were the highest compared to the other fractions, rang .i ng from 39.2 6tvIJ /Kg in F. sycomorus Kj to Sl.Q8~in F." ingene. The species were found to have considerably high amounts of po1yphenols compared to other f ract i ons . .. , The amounts were as high as 9.26% in F. volgelii. A rating scheme applied to the ten species showed that F. benjamina, F. glumosa and F. volgelii are candidates for further investigation as potential mUltipurpose crops. The E-phenylphenacyl esters of the saturated fatty acids series ClZ - C22 (lauric, myristic, palmitic, stearic, arachidic and behenic) were prepared by Vl reaction of their potassium salts with p-phenylphenacyl bromide. The esters were identified by their m.p., IR and NMR spectra. High performance liquid chromatography of the esters on a reverse phase column, with methanol solvent, gave a straight line when the log of the r~tention time was plotted against molecular weights. This analytical method when applied to p-phenylphenacyl esters made from coconut oil gave peaks which corresponded to lauric, palmitic, and st~earic acids. When the method was applied to the F. volgelii oil fraction, several peaks were observed which did not appear to correspond to any of the s~aturated acid peaks