Comparative examination of biologically
active compounds of fatty oils of medical and alternative herbs separated by cold-moulding

- S. Makai - J. Balatincz -
Pannon University of Agricultural Sciences,
Mosonmagyaróvár

Introduction and literary review

Alteration of the conditions in the economics agricultural production has made the searching important for those possibilities of the production of such goods which are in good quality and are competitive in abroad by the exploiting of the agroeocological potention of Hungary. Beyond the demands of the exacting market by the reason of changes in oecological presumption of cultivation - mainly the mediterrian effect - the cultivation of such plant species has bee raised which have not had tradition before. The effect of the global clime alteration onto the plant cultivation has made the importance of producing new alternative plant species reasoned. The aim of our research work was to study the determination of the quality of the end-product and the cultivation of fruits of such plants which could be alternative besides the traditional field culture.

From amidst plants having fatty oils the quality of pressed oils of safflower fruit (Carthamus tinctorius L.), pumpkin (Cucurbita pepo convar. pepo var. Styrica) and coriander (Coriandrum sativum L.) from among the traditional plants the fruit of hemp (Cannabis sativa L.) and in our experimental region the fruit (rhizome) of tigernut (Cyperus esculentus) have been studied. According to the literature the oil of safflower contains a lot of valuable unsaturated fatty acids and besides its utilisation in salads and foods this plant is applied in human therapeutics for the prevention of arteriosclerosis. Usage of safflower in cosmetics is also perspective. (Kiss B.-Domokos J. 1995, Szabó L. Gy. 1973)

The conventional safflower oil acts as a drying lacquer. Due to this feature this oil is utilised also in dye- and lac industry in addition it gives high glitter of lacquers and this fade does not turn yellow during years. In India a gel-like polymer is produced from this oil by heating it on 300^oC and after keeping it on this temperature for two hours, the oil is dribbled into water. The end-product is applied for sticking glasses and precious stones. If terepinthine is used instead of water material for cloth impregnation and preservation of leathers can be produced.

Pumpkin has become an important medicine source in the last decade. Its matured seed (Cucurbita semen) and its oil (Oleum cucurbitae) is world wide spread. The preventional dietetics role (e.g. in arteriosclerosis) is becoming more significant. The fatty oil content of its seed is 40-60% including polyunsaturated fatty acids and fatty acid residues. The rate of linolic acid reaches the 40-50%. The polyunsaturated fatty acids are important precursors of prostaglandines and cerebrosides which play role in the function of the brain and nerve system. The high vitamin E content (above 30mg%) has antioxidant effect and also improves the storage of the oil. Its vitamin A and selenium content is also noticeable. The advantageous effect of pumpkin-seed oil has been proved on prostate hypertrophy, inflammations and in treatment of arteriosclerosis. The medicine produced from the oil (e.g.Peponen) is applied wide spread in cure the retention of urine due to prostate hypertrophy, dermatitis, delaying arteriosclerosis, improving the physical and mental productivity, and increasing resistance (Hornok L. 1990, Schicher, H. 1986).

The fruit of coriander (Coriandri fructus) contains 0.2-1.0% volatile oil, 20% fatty oil, 14% protein, tanning agent and vitamin C. As a spice and medical herb it is used in treatment of digestive disorders, and as a component of anticonvulsive and carminative medical herb mixtures. The main component (60-70%) of the oil is linallol (coriandrol) but besides this even baras camphor, a and b phellandrene, a and b pinene, champhene and a and b terpinene can be found in it.

About the application of its cold-moulded fatty oil only a few literature were found. One of the possible utilisations of it is as an aroma component to muscatels in the amount of 10-20ppm (Vas G 1996).

The most important nutritive agents of the hemp seed are the fatty acids. Those unsaturated fatty acids which cannot be synthesised by human and animal organisms are calledknown as essential fatty acids. In this group five fatty acids have been inculdede before: the unsaturated oleic acid (C18:1), the palmic acid (C 16:1), the linoleic acid with two double bonds (C18:2), the linoleic acid with three double bonds (18:3) and the arachidoneic acid which contains four double bonds (C 20:4). Since the nutritionists and physicians say only the linolic acid essential(!) the highest rate of this fatty acid is needed. Besides this the highest concentration of oleic acid is said to be disadvantageous and even the lowest content of linoleic acid is recommended due to their inhibiting effect on the metabolism of linolic acid. With the help of the fatty acid analysis of different type of hemp seeds the perfection of the fatty acid composition of hemp oil has been determined thus it can compare with the best sunflower-, soy-, and corn germ oils. Extremely high linolic acid and unsaturated fatty acid values were detected. Hemp contains significant concentration of niacin what is an important compound of the vitamin B complex and plays noticeable role in the function of the nervous system, the maintenance of healthy tissues of the skin, tongue and digestive tract but it is also vital to the synthesis of sexual hormones. Since the essential fatty acids are highly important to keep the skin and other tissues young, they defend the skin from drying out, chapping and xeroderma, thus they could be used also in the cosmetics (Kralovánszky et al.1994., Then M. et al.1996.).

The biological value of the tigernut oil (Cyperus esculentus), the physical and chemical features (viscosity, energy content, iodine value) have been found equal with the soy-, sunflower-, and rapeseed oil. The oil of tigernut also can be used as biodiesel fuel. By the study of Zhang et al. the phosphorus content of this oil is significantly high the peroxide and the melting value is noticeably lower but its fatty acid composition is similar than that of other plant oils (Zhang et al.1996.). During the chromatographic and chemical examinations Eteshola has found that the dominant saturated fatty acid was the miristinic acid and the dominant unsaturated fatty acid was the oleic acid. The value of linolic acid was found as 8.8%, any other polyunsaturated acids were not detected. It is applicable for mixture oil stirred with other vegetal oil (Eteshola et al. 1996., Omode et al. 1995.).

The quality of oils produced by cold-moulding from the fruits of plants cultivated in the area of Kisalföld have been compared with the quality of oils produced in the same method and which are already put in circulation in the West European markets.

Materials and methods

The cold-moulding of fatty oils was performed on Hungarian product of OP222 oil-press. The pressed oils were cleaned by centrifugation. The determination of the fatty acid content of the samples was according to the MSZ 19928-73 norm. The principle of this determination technique is the aesterification of the fatty acids of the oils to methylesters and separation by gas-chromatographic method. By the results of the chromatogram the fatty acid content of the samples and the fatty acid composition could be calculated. This method can be applied to determine fatty acids with 8-24 carbons. The contents of fatty acid methylesters were determined by the area under the peaks which are specific to the certain component.

Results and discussion

The fatty oil content of the examined plant species differed from each other. In the case of fruit of safflower .the fatty acid value was 24.2% while in the seed of pumpkin it showed 52.4%. The fatty oil content in coriander fruit was 26.7% and in tigernut fruit 27.8%. The values of fatty acid composition of the vegetal oils are shown by Table 1. and Figure 1.

Table 1.
Fatty acid content of the examined oils

According to the results of our study the linolic acid content of safflower showed a significantly high value from among the examine vegetal oils. In the three sample in the point of linolic acid content no difference was found, but the oleic acid concentration was the highest in safflower produced in our cultivation area, this value exceeded the 6.4% which content is equal with the value of commercial safflower oils in abroad. In the latter ones the linolic and oleic acid rate -which determines the nutritional value- is more advantageous. Safflower oil with golden yellow colour, sweet smell and taste is perfect to improve the quality of other vegetal oils.