Economically Useful Plants of Sri Lanka Part V . * Seed Fats of some Garcinia Species ( Guttiferae ) 2 .

Seed fats of four Garcinra species have been analysed. Percentages of acids 1n the seed fats have been compared. Ga~cinia bzinucao secd has been found to be a good source for stearic and oleic acids.


Introduction
The fat from coconut kernel, also called coconut oil, is used very extensively in Sri Lanka as a source of food and also in soap manufacture.With the escalation of coconut oil prices there is a necessity to find an alternative for coconut oil.With this view, we analysed the seed fats of some Garci~zia species and the results are reported in this papel.

Results and Discussion
The seed fats of the following Garciizia spovcies were obtained: Garcinia bunucao, Garcinia cornea, Garcinia dhlci,s and Garcinia xanthocl~ymas.The seeds were crushed and extracted with light petroleum.Evaporation of the solvent yielded the fat in each case.Table I gives the percentage fat present in the seeds studied.The fats were hydrolysed end the hyarolysates wcre esterified using BF,-MeOH.Methyl esters of the fatty acids were subje~ted to gas liquid chromatographic analysis.Tlze percentage compositions of the faity acids are given in Table 2.The seed fats of G. cEulcis and G. xarithoclzymas are remarkably similar.There is some resemblance between the seed fats of G. cornea and G. bunucao despite the apparent reversal of the relative contents of stearic and oleic acids and the higher content of linoleic acid in the folrner.The seed fat of G. bunucao is interesting because it qonsists almost enti~ely of two acids: stearic and oleic acids.Oleic acid is used in the preparation of soft soaps.The barium salt of oleic acid js used in rodent exterminati~n.~The present study reveals that the G. bunucao seed is a good souice for stearjc acid which is required in the rubber compounding.Unfortunately the *For Part IV see S. J. Balasuriya, S. Sotheeswaran and S. Balasubramaniam, J, Natn.Sci.Coun.

Z. A . M. Faisai, S. Sothee*:aran and C. Wijesundera
seeds examined had a iow linoleic acid content.This is an essential fatty acid and it is nutritionally important.G. cornea seed fat had 12.5 % of this essential fatty acid.
The fatty acid composition of the seed of G. bunucno is similar to those reported for the seeds of G. morellal and G. indica3 The seeds were collected from the trees glowing in the Peradeniya Botanical Gardens.The seeds were dried, crushed and were separately extracted -with light petroleh in a soxldet.The light petroleum extracts were considered as fats.The fats.were hydrolysed with methanolic KOH: The acids were isolated'in the usual manner and their methyl esters' were subjected to gas-liiuid chromatographic examination.

Preparation of methyl esters
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The acids were identified by the retention times of their methyl estexs and their peak areas were used to calculate the percentages.

Gas-liquid chromatography
Gas chromatography was carried out on a Varjan Model 2440 chro~natograph equipped with a flame ionisation detector and using glass columns (1.8 m x 2 mna i.d.) packed with 10 % SP 2340 coated on 100j120 chromosorb WAW.The column was maintained at 190°C.Argon was used as the ca~tier gas at a flow rate of 30 ml min-'.

TABLE 1 . Percentage fat in the seeds of some Garcinio species - Species % fat Garcinia bunrtcao 50 Gorcinia cornea 60 Garcinia drrlcis Garcinia xcinthochymasTABLE 2 . Percentage acids in the seed fats of some Garcinia species
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