FATTY ACID COMPOSITION AND TOCOPHEROL CONTENT OF AMAZONIAN PALM OILS

The characteristics of oils recovered from seeds of Astrocaryum chambira and A. urostachys have been evaluated. The gas chromatographic analyses showed that lauric and myristic acids are predominant fatty acids accounting for 50.8–52.3 and 26.2–28.1% of the total, respectively; thus, resembling closely to palm kernel stearines. Tocotrienols were the major antioxidants present in both Astrocaryum chambira and A. urostachys Kernel oils. Application of these oils in the confectionery industry without use of any fractionation techniques is recommended.     

RECOVERY OF PALM CAROTENE FROM PALM OIL AND HYDROLYZED PALM OIL BY ADSORPTION COLUMN CHROMATOGRAPHY

Crude palm oil and crude palm olein were hydrolyzed with lipase from Candida rugosa to produce a free fatty acid (FFA) rich oil. The percentages of FFA produced and carotene degradation after the hydrolysis process were determined. The palm oil and hydrolyzed palm oil were subsequently subjected to column chromatography. Diaion HP-20 adsorbent was used for reverse phase column chromatography at 50C. Isopropanol or ethanol, and n-hexane were used as the first and second eluting solvents, respectively. The objective of hydrolyzing the palm oil was to produce more polar FFA-rich oil in order to enhance the nonpolar carotene bind to the nonpolar HP-20 adsorbent in the column chromatography process. Hydrolyzing palm oil with lipase from Candida rugosa gave 30- and 60-fold, respectively, of FFA in the crude palm oil and crude palm olein in 24 h at 50C. Approximately, 15.56 and 17.48% of carotene degraded in crude palm oil and crude palm olein, respectively. For column chromatography, using isopropanol or ethanol as the first eluting solvent, unhydrolyzed oil and hydrolyzed oil showed the carotene recovery infraction two (carotene-rich fraction) of about 36–37 and 90–96%, respectively. Over 90% of carotene recovery was obtained from     

SEPARATION OF TOCOPHEROL SUCCINATES FROM DEODORIZER DISTILLATE

Isolation of tocopherol succinates from sterol-removed, succinated deodorizer distillate (DOD) mixture by crystallization was investigated. Membrane technology was also evaluated for its effectiveness to separate tocopherol succinates from mixtures containing sterols and tocopherols. Crystallization was conducted at −20C for 24 h with different solvents, including hexane, petroleum ether, and a mixture of acetone and methanol (4:1, v/v). The crystallization results showed that recovery of tocopherol succinates from the cake fraction was poor with all solvents tested, with less than 10% of original tocopherol succinates in the raw material being crystallized under conditions employed. Among the solvents tested, hexane was better for the recovery of non-α-tocopherol succinates in the cake fraction. Furthermore, a high properties of free fatty acids (FFA) was co-crystallized along with tocopherol succinates for all solvents used, leading to tocopherol succinates contents in the cake fractions lower than that in the raw material. Two nanofiltration membranes (DS-7 and AP01) were also examined using hexane or petroleum ether as a solvent. The recovery of tocopherol succinates was over 60%. However, their concentration was increased only by 6%. A combined process was then evaluated that included crystallization before succinylation, succinylation, first stage membrane separation, and second stage membrane separation. The final tocopherols concentration derived from this combined process was mice as much as that of the original DOD.     

SEPARATION OF INDIVIDUAL CATECHINS FROM GREEN TEA USING SILICA GEL COLUMN CHROMATOGRAPHY AND HPLC

Crude catechin mixtures from green tea were separated into six fractions using a silica gel column chromatography and a chloroform-methanol-water (65:35:10, v/v/v, lower phase) solvent system. Fraction I was free of catechins, fraction II contained epicatechin (EC), fraction III had epicatechin and epigallocatechin (EGC), fraction IV possessed EGC, fraction V contained EGC, epicatechin gallate (ECG) and epigallocatechin gallate (EGCG), and fraction VI had EGCG. EC and EGC were separated from fractions II, III and IV using HPLC with a RP-18 semipreparative column and a water-dimethylformamide-methanol-acetic acid (157:40:2:1, v/v/v/v) solvent system. For isolation of EGC, ECG and EGCG from fractions V and VI a water-acetonitrile-methanol-acetic acid (159:36:4:1, v/v/v/v) solvent system was employed. Chemical structures of purified catechins were further confirmed by ESI-MS.     

SIMULTANEOUS DETERMINATION OF FREE FATTY ACIDS, PARTIAL ACYLGLYCEROLS AND TOCOLS IN PALM OIL PRODUCTS USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

A high-performance liquid chromatographic (HPLC) method is described for the simultaneous separation of lipid classes and vitamin E isomers. The detection of both groups was made possible by using an evaporation light scattering detector and a fluorescence detector connected in series. Separation of partial acylglycerols and free fatty acids was satisfactory. In addition, five major vitamin E isomers in palm oil, namely α-tocopherol, α-, β-, γ- and δ-tocotrienols were also resolved. The accuracy of the method, in terms of partial acylglycerols and free fatty acid, was in agreement with the result obtained from the gas chromatographic method. The mean recovery of α-tocopherol on spiked tripalmitin was 95.2%.     

SEPARATION OF STEROLS FROM DEODORIZER DISTILLATE BY CRYSTALLIZATION

Separation of sterols from deodorizer distillate (DOD) by crystallization without pretreatment was investigated. DOD was dissolved in different solvents and crystallization was then conducted at-10 or-20C, with a solvent-to-DOD ratio of 3:1 (v/w). Several solvents such as methanol, acetone, and their mixtures, were examined for their separation effectiveness. The sterol crystals formed were removed from the solution by centrifugation at low temperature and subsequent filtration. The best results were obtained by crystallization at -20C for 24 h with a mixture of acetone and methanol, followed by centrifugation, filtration and washing steps. Over 90% of the original tocopherols and squalene in DOD were recovered in the filtrate fraction, while 80% of total sterols in DOD were retained in the cake fraction.     

DIETARY FATTY ACIDS, TOCOTRIENOLS AND CANCER

High-fat diets may increase the risk of cancer at sites such as the breast, colon, pancreas and prostate, although the evidence is somewhat mixed. The type of fat can affect its influence on cancer in experimental animals, but in humans on diets of mixed foodstuffs the quantity rather than the quality of fat is likely to be more important. Dietary fat may influence carcinogenesis by altering energy balance and in mammary cancer the effects may be mediated by the mammary adipose tissue. A variety of minor dietary components have been reported to possess anti-cancer activity. Among these compounds, tocotrienols and flavonoids have been shown in our laboratory to inhibit proliferation of human breast cancer cells in culture, and to act synergistically with each other and with tamoxifen in the inhibition of these cells. This suggests that such combinations may be useful for prevention and/or treatment of breast cancer.     

OPTIMIZATION OF CAROTENE RECOVERY FROM HYDROLYZED PALM OLEIN IN ADSORPTION COLUMN CHROMATOGRAPHY USING RESPONSE SURFACE METHODOLOGY

Response Surface Methodology (RSM) for optimization of carotene recovery from hydrolyzed palm olein (HCPOlein) in adsorption chromatography was carried out. The level and interaction of three independent variables was investigated: column temperature (50 to 60C), oil loading (25 to 200 g), and mobile phase flow rate (6 to 60 mL/min). Based on the response as percentage of carotene recovery from 50 g of HP-20 adsorbent, the optimum conditions were achieved at 200 g of oil loading, column temperature at 55C, and flow rate at 33 mL/min. Up to 98% of carotene recovery was obtained under these conditions. Interaction of oil-oil, oil-flow rate and flow rate-flow rate could enhance the percentage of carotene recovery. However, oil and flow rate as single factors could significantly reduce percentage of carotene recovery. Oil loading as a single factor could positively influence the amount of carotene adsorbed. However, flow rate as a single factor and oil-oil interaction could negatively influence the amount of carotene adsorbed. The mean of difference (MD) of the experimental and predicted data for percentage of carotene recovery and the amount of carotene adsorbed were very small, −0.0067 and 0.0133, respectively. The probability (P) value showed no significant lack-of-fit for both equations in this model.     

A SIMPLE METHOD FOR THE ISOLATION OF PURINE NUCLEOSIDES FROM WORT AND BEER USING COLUMN CHROMATOGRAPHY

Column chromatography using a variety of dextran based gel matrices was used to fractionate nucleosides in wort and beer. The gel matrices Sephadex G10 and Sephasorb HP Ultrafine were found to elute guanosine, deoxyguanosine, adenosine and deoxyadenosine in a single fraction whereas Sephadex LH20 and Sephadex G25 both yielded two fractions containing nucleosides. The first nucleoside containing fraction from Sephadex LH20 contained guanosine and the second fraction contained deoxyguanosine, adenosine and deoxyadenosine. In contract the first nucleoside containing fraction from Sephadex G25 contained both adenosine and deoxyadenosine and the second fraction contained guanosine and deoxyguanosine. Fractionation of low molecular weight components from wort and beer by column chromatography provides a simple technique for the isolation of purine nucleosides. This may be used to monitor directly the presence of purine nucleosides throughout the brewing process and to obtain quantitative estimates of the content of purine nucleosides in beer.     

EFFECT OF DEGUMMING PROCESS ON CHROMATOGRAPHIC SEPARATION OF CAROTENES FROM CRUDE AND DEGUMMED PALM OIL

Carotene from crude palm oil (CPO) and degummed palm oil (DPO) was separated using synthetic polymer adsorption chromatography. Diaion HP-20 adsorbent was used for reverse-phase chromatography and column temperature was kept at 50C. Both 2-propanol and n-hexane were used as the first and the second eluting solvents, respectively. Phosphoric acid was used to remove the minor components in CPO in the degumming process. The turbidity of DPO was lower than that of CPO and the retention time in the column for DPO was shorter (21.3 min) compared to CPO (29 min) due to the removal of the minor components by phosphoric acid. Degumming process caused a reduction of 1.67 mg of total carotene content and 55.67 ppm of carotene concentration in CPO. This is probably due to the removal of carotenoids during the degumming process. After column chromatography, carotene recovery for CPO was 30.23% and 54.82% for the first and second fractions, respectively. On the other hand, carotene recovery for DPO was 33.91% for the first fraction and 46.25% for the second fraction. This indicated that the separation of carotene in CPO was more efficient than DPO in the column chromatography due to the longer retention time in the column.     

棕榈油脂肪酸单乙醇酰胺的合成研究

通过对投料比、温度、压力、催化剂用量等影响因素的系统考查，研究了合成棕榈油脂肪酸单惭醇酰胺的优化条件，产物经化学分析和ＩＲ谱图分析，纯度较高，酰胺含量在９０％以上。     

FATTY ACID COMPOSITION AND CONJUGATED LINOLEIC ACID CONTENT OF COW AND GOAT CHEESES FROM NORTHWEST ARGENTINA

ABSTRACT

In this study, we evaluated chemical characteristics, fatty acid composition and conjugated linoleic acid (CLA) content of cow and goat cheeses from Northwest Argentina. Similar chemical and fatty acid composition were determined in milk and cheese of both species. Palmitic, oleic and myristic acids were the most abundant fatty acids in dairy products. CLA level averaged 0.85 and 0.96 in milk and 0.76 and 1.04 g/100 g of fatty acids in cheese of cow and goat, respectively. Cis‐9,trans‐11 was the major isomer present in both species. Significant differences in CLA desaturase activity were observed, showing a value of 0.068 and 0.064 in milk, and 0.077 and 0.071 in cheese of cow and goats, respectively. Good nutritional properties were determined for cheeses of both species, which are fed on natural pasture during spring and summer seasons. Goat's cheese represents a higher source of CLA for human consumers than cow's cheese, offering from 156.6 to 222.6 mg/ 100 g of sample.

PRACTICAL APPLICATIONS

The present work shows the fatty acid composition and chemical characteristics of two fresh cheeses manufactured with cow and goat milk. Animals were fed on natural pasture during summer and spring seasons. It is known that pasture increases conjugated linoleic acid (CLA) concentration in milk fat, and the content in cheese is directly related to it. The CLA content of dairy products for the human consumers was analyzed, showing goat cheese with high polyunsaturated fatty acid content, including CLA. Cow and goat fresh cheese offer CLA as many ripening products of different countries, as cheddar or hard cheeses. Lipid composition of food is related to many illnesses, but some compounds are beneficial to human health. The main sources of CLA are milk and cheeses, and in Northwest of Argentina, no data are reported about it, where artisanal cheeses are consumed by the population. Therefore, the atherogenicity index was determined as well.     

SEPARATION OF NITROGENOUS CONSTITUENTS OF MALT,WORT AND BEER USING HIGH PERFORMANCE LIQUID CHROMATOGRAPHY

High performance liquid chromatography has been used to separate groups of soluble nitrogenous compounds in malt. Malts are extracted with water at 5°C and the nitrogenous components separated using a column packed with a material designed specifically for the analysis of proteins and peptides. The procedure is suitable for routine use and can be readily adapted to study changes in the development of nitrogenous compounds during the brewing process.     

FATTY ACID COMPOSITION OF LIPIDS FROM BROILERS FED SATURATED AND UNSATURATED FATS

SUMMARY— The effect of feeding saturated fat (tallow) and unsaturated fat (safflower oil) to broilers on the change in fatty acid composition of lipids deposited in broiler tissues at 4, 6, 8, and 10 wk of age was determined. Fatty acids from raw and cooked skin, excluding that on the neck and third wing joint, breast meat, thigh meat, and abdominal fat were identified by using gas liquid chromatography. Fatty acids from water in which carcasses were cooked were also identified. The degree of unsaturation of fatty acids in these tissues wars influenced by the degree of unsaturated fatty acids in the diet and tended to assume the fatty acid composition of the diet. In some cases, however, the higher levels of certain fatty acids in depot fat was not present in broilers fed the higher levels in the diet. Fatty acids in the larger amounts in all broiler tissues were palmitic, stearic, ofeic, and linoleic but varied in amount among the different age broilers fed the same ration as well as different rations. In most cases there tended to be an inverse relationship between oleic and linoleic acids in the tissues. Lipids from cooked tissues contained a larger amount of 18-carbon unsaturated fatty acids than the other fatty acids combined. Fatty acids collected from cooking water were similar to those in cooked tissues. The presence of 13- and 25-carbon chain fatty acids noted in tissues of 4 wk-old broilers suggests a difference in the metabolism of fat in different age birds. Futher research is needed to substantiate this finding.     

DETERMINATION OF BENZOIC AND SORBIC ACID IN TURKISH FOOD USING HIGH-PERFORMANCE LIQUID CHROMATOGRAPHY

Benzoic and sorbic acid levels in different brands of jam, candied chestnut, carbonated drink, pickle, black table olive, green table olive, wholemeal/brown bread and white bread, which are available on the Turkish market, were determined by high-performance liquid chromatography with diode array detector (235–254 nm). Chromatographic separation was achieved with a C18 column and acetate buffer (pH 4.74)–methanol mixture (70:30) as a mobile phase. The levels of benzoic and sorbic acid in the analyzed samples were in the range of not detected to 662 mg/kg or L, and not detected to 432 mg/kg or L, respectively. Only one sample (jam) presented a preservative although not permitted by the legislation enforced in Turkey. The levels of preservative in the other samples were determined in legal limitations. According to the results, the utilization of benzoic and sorbic acid is lower than the certain legal limitations permitted by legislation to be used.

PRACTICAL APPLICATIONS

The amount of the sorbic and benzoic acid used as preservatives during food processing is important for consumer health. Determination of the amounts of the preservatives mentioned above will be possible in a short period of time (11 min) with the methods used in this study (high-performance liquid chromatography). According to the results obtained from study and data about food consumption, daily intake amount of these preservatives (benzoic and sorbic acid) will be able to be defined in Turkey, separately.     

蚕蛹油中多不饱和脂肪酸的分离研究

蚕蛹油富含亚油酸、α-亚麻酸等多不饱和脂肪酸,这些多不饱和脂肪酸有多方面的生理功能.主要介绍蚕蛹油中多不饱和脂肪酸的尿素包合分离和硝酸银络合分离.结果表明,适宜的尿素包合条件为:尿素/脂肪酸的质量比15:1、包合温度5℃、包含时间2 h,在上述条件下多不饱和脂肪酸得率为70.0%,含量达到92.4%;适宜的硝酸银络合条件为:AgNO32mol/L、40%甲醇-水溶液、络合温度0 ℃,在上述条件下α-亚麻酸收率达50%,纯度达99%.