CHEMICAL COMPOSITION OF OIL FROM COULA EDULIS (Bail.) NUTS

Coula edulis (Bail.) nuts are generally used as food components in the littoral and southern part of Cameroon. The physicochemical characteristics, the fatty acids and the triacylglycerols (TGs) of Coula edulis (Bail.) nut oil from two different agroclimatical zones of Cameroon were studied. The oil content varied according to the zone (33.50 – 36.65%). The iodine value (90 – 95), saponification value (180 – 185) and the nitrogen (2.16 – 2.40%), and ash (2.5 to 2.7%) contents were similar for the two types of nuts studied. The main fatty acid of the oil was oleic acid (95.5 – 97.4%), as determined by capillary gas chromatographic analysis. The triacylglycerol profile obtained by reversed phase liquid     

CHEMICAL COMPOSITION AND ANTIMICROBIAL PROPERTIES OF THE ESSENTIAL OIL OF ORIGANUM SACCATUM L.

The chemical constituents of essential oil isolated by hydrodistillation of aerial parts of Origanum saccatum L. growing wild of 39 constituents were identified accounting for 99.11% of the oil of O. saccatum. The oil of O. saccatum contained, as main components, p -cymene (82.8%), γ-terpinene (6.2%), p -cymene-8-ol (1.5%) and carvacrol (1.2%). The essential oil of O. saccatum was characterized by its high content of p -cymene.
Preliminary experiment was carried out in vitro using the diffusion method to investigate antimicrobial activity of the O. saccatum oil. The oil exerted varying levels of antimicrobial effects on the growth of all microorganisms (except for 100 ppm which belongs to Bacillus subtilis, Bacillus aureus ). The antimicrobial activity of the O. saccatum oil was established by using agar diffusion method. The results showed that antimicrobial activity increased depending on the concentration degree used. The highest sensitive bacteria had Staphylococcus aureus and Escherichia coli. As a result, inhibitory effect of oil was weak on tested bacteria compared with fungi. The extent of inhibition of tested microorganism growth was dependent on the concentrations of essential oil used.

PRACTICAL APPLICATIONS

Some investigations showed that the use of spices in place of chemicals and synthetics has become indispensable because of their antimicrobial effects and also because of the increasing risk of the side effects of chemical and synthetic preservatives on health. Also, spices and derivatives have been used since ancient times to preserve foods, make foods tastier, cure diseases and produce aromatic substances. Many species of aromatic plants belonging to the Labiatae family grow wild in the east Mediterranean basin. Dried oregano leaves are well known not only in the herb industry mainly but also for other appetizing applications, and as a source of essential oils     

COMPARISON OF CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF GLYCOSIDICALLY BOUND AND FREE VOLATILES FROM CLOVE (EUGENIA CARYOPHYLLATA THUNB.)

The present article reports on the chemical composition and antioxidant activity of clove glycosidically bound volatile compounds in comparison with their essential oil. The comparison of chemical composition of volatile aglycones with the chemical composition of essential oil revealed only eugenol as identical. To measure the antioxidative activity of the clove enzymatically released aglycones and its essential oil, two different assays were performed: the 2,2'-diphenyl-1-picrylhydrazyl (DPPH) radical-scavenging method and the ferric reducing/antioxidant power (FRAP) assay. Both methods showed that the clove volatile aglycones possess lower antioxidant properties than its essential oil. The volatile aglycones radical-scavenging activity measured by DPPH method was lower than butylated hydroxytoluene (BHT) and butylated hydroxyanisole (BHA) activity. The reducing capacity measured by FRAP method for volatile aglycones was lower than BHA capacity and higher than BHT capacity. Some differences in activity obtained by two methods could be explained with different solvent polarity.

PRACTICAL APPLICATIONS

Many secondary metabolites are glycosylated and accumulate as nonvolatile glycosides. Since the glycosides are able to release their aglycones by enzymatic hydrolysis, these compounds could be considered as possible precursors of antioxidant substances in plant. They may contribute to the total antioxidant activity of plant and could be used as natural antioxidants.     

CHEMICAL COMPOSITION AND PHYSICOCHEMICAL PROPERTIES OF HORSE MEAT FROM THE LONGISSIMUS LUMBORUM AND SEMITENDINOSUS MUSCLE

The objective of this study was to compare the chemical composition and physicochemical quality of the meat of mature slaughter horses (73 mares and 58 geldings) sampled from the longissimus dorsi (longissimus lumborum section [LL]) and semitendinosus (ST) muscles.
The LL muscle was characterized by significantly lower values of electrical conductivity, temperature and shear force; however, it showed a significantly higher water-holding capacity. Meat from the LL muscle showed a significantly higher intramuscular fat (IMF) content, and as a result, higher calories, but contained less water and protein than the ST muscle. Along with the increasing marbling level, the IMF content in the LL muscle increased from 2.79 up to 13.30%, whereas in the ST muscle, from 2.80 up to 6.45%. Generally, a higher meat marbling goes together with a decrease of water and protein contents as well as an increase of a protein/fat ratio.

PRACTICAL APPLICATIONS

On the basis of the obtained results, it was stated that the chemical composition and physicochemical quality of mature horses' meat was similar to some other species of red meat. Therefore, the horse flesh could be a valuable substitute of culinary meat, especially beef. The high dressing percentages reflected the horses' usefulness for meat production. Moreover, considering a slight number of defects occurring in horse meat (i.e. DFD or PSE), chevaline could be more widely used in the meat industry, in raw or processed form, as a suitable food for human consumption.     

CHEMICAL COMPOSITION AND ANTIOXIDANT ACTIVITY OF SAPOTA (ACHRAS SAPOTA LINN.) FRUIT

Sapota (Achras sapota Linn.) belongs to the family Sapotaceae and is assigned for various properties in the traditional system of Indian medicine. For the first time, nutritional quality and antioxidant activity of sapota juice with reference to its chemical composition have been investigated employing various well‐established in vitro methods. Chemical composition analysis of sapota juice revealed that it is one of the rich sources of sugars, proteins, ascorbic acid, phenolics, carotenoids and minerals like iron, copper, zinc, calcium and potassium. Apart from the nutritional components just given, sapota juice showed potential antioxidant activity against 1,1‐diphenyl‐2‐picrylhydrazyl free radicals and superoxide radicals. Sapota juice potentially inhibited the free radical‐mediated lipid peroxidation in a liposome model system. Total reducing‐power assay revealed the potential reducing power of sapota juice. The multiple radical‐scavenging potential of sapota juice was found to be due to its nutraceutical components, viz., phenolics, carotenoids and ascorbic acid.     

干、生姜黄的挥发油提取及成分研究

以广西那坡县产的姜黄为原料，分别以水蒸汽蒸馏法和以石油醚为溶剂的索氏提取法提取干、生两种姜黄的挥发油，并用GC-MS分析法对这几种姜黄挥发油的主要成分进行了研究，结果表明：无论是用索氏提取法还是水蒸汽蒸馏法均以干姜黄做为原料的提取率比较高；在这几种挥发油中相对含量超过4％的共有组分为α-姜黄烯、芳姜黄酮、β-倍半水芹烯、α-姜黄酮、β-姜黄酮等5种成分；这二种提取法在成分上最明显的区别在于以水蒸汽蒸馏获取的姜黄挥发油不合（-）-姜烯。     

抽油烟机回收油的脂肪酸组成变化特征研究

食用油在烹饪过程中挥发,会在抽油烟机系统中凝结。分别以花生油、葵花籽油、茶籽油、玉米油和调和油5种不同植物油为食用油进行烹饪试验,收集经抽油烟机系统凝结的油脂。通过测定抽油烟机回收油和相应未烹饪油的脂肪酸,来分析回收油脂肪酸组成变化特征。结果表明,回收油的脂肪酸种类和含量显著性差别于未烹饪油(P0.05)。回收油增加了C14∶0、C16∶1n7c短碳链脂肪酸,其饱和脂肪酸的含量增加了,不饱和脂肪酸含量减少了,其脂肪酸不饱和度明显降低,仅是未烹饪油的50%~61%。回收油中短碳链脂肪酸有增加的趋势,长碳链脂肪酸含量有减少的趋势,而且新增了食用油本底很少或没有的C18∶3n3c和EPA脂肪酸。回收油的品质也开始变化,有些回收油的脂肪酸已严重偏离了正常植物油的特征值。因此,抽油烟机回收油已不适合再食用,烹饪过程中应降低烹饪温度以减少食用油的变质。     

COMPOSITION OF CROCINS AND PICROCROCIN FROM SPANISH SAFFRON (CROCUS SATIVUS L.)

A method for simultaneous identification and quantification of crocins and picrocrocin by HPLC-DAD in aqueous extracts of saffron spice was used. The coefficients of variation obtained were lower than 10% for a majority of the crocins and picrocrocin. These substances are not found as standard compounds, for this reason it was necessary to obtain the response factor for each compound by collecting the fractions of each chromatographic peak and by using molar absorpitivity. This method can be used not only for crocins and picrocrocin determination but also for adulteration detection of saffron with water-soluble colorants. The method was applied to 260 samples of Spanish saffron, which came from the regions where saffron is an important crop, i. e., Castilla-La Mancha and Aragón. Spain is in the top group of saffron producers and Castilla-La Mancha is the largest saffron producing region in Spain. Four crocins and picrocrocin were ranked and the values used for differentiation according to origin. Only discriminant analysis could explain 100% of the variance by samples and location. The major discriminant variable was trans-crocin 4.