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1.
Food Res Int ; 105: 507-516, 2018 03.
Article in English | MEDLINE | ID: mdl-29433242

ABSTRACT

In this work, an Italian extra-virgin olive oil (EVOO) sample and the same sample added with a carotenoid-rich nutraceutical extract from Lycium barbarum L. (EVOOCar) were subjected to a frying process to comparatively assess chemical and physical changes and heat stability. Oxidation progress was monitored by measuring oil quality changes such as peroxide value, free acidity, K232, K268, and fatty acid composition as well as minor compound content, phenols, α-tocopherol, and carotenoids. An UHPLC/QTOF-MS metabolomics approach discriminated the two oil samples based on their chemical changes during frying, identifying also the phenolic classes most exposed to statistically significant variations. Partial least square discriminant analysis and volcano analysis were applied together to identify the most significant markers allowing group separation. The decrease in total phenolic content was lower in EVOOCar than in EVOO during frying. Monounsaturated and polyunsaturated fatty acids showed a significant percentage loss, 3.7% and 17.2%, respectively, in EVOO after 180min frying at 180°C, while they remained constant or slightly changed in EVOOCar. Zeaxanthin added to the oil rapidly decreased during the frying process. These findings showed that the addition of a carotenoid extract from L. barbarum can help to improve the oxidative stability of extra-virgin olive oil.


Subject(s)
Carotenoids/chemistry , Cooking/methods , Food Handling/methods , Hot Temperature , Lycium/chemistry , Metabolomics/methods , Olive Oil/chemistry , Carotenoids/isolation & purification , Chromatography, High Pressure Liquid , Fatty Acids, Unsaturated/analysis , Hydrogen-Ion Concentration , Mass Spectrometry , Oxidation-Reduction , Peroxides/analysis , Phenols/analysis , Time Factors
2.
J Anal Methods Chem ; 2016: 7482620, 2016.
Article in English | MEDLINE | ID: mdl-27547482

ABSTRACT

Stereospecific analysis is an important tool for the characterization of lipid fraction of food products. In the present research, an approach to characterize arabica and robusta varieties by structural analysis of the triacylglycerol (TAG) fraction is reported. The lipids were Soxhlet extracted from ground roasted coffee beans with petroleum ether, and the fatty acids (FA) were determined as their corresponding methyl esters. The results of a chemical-enzymatic-chromatographic method were elaborated by a chemometric procedure, Linear Discriminant Analysis (LDA). According to the total and intrapositional FA composition of TAG fraction, the obtained results were able to characterize roasted pure coffee samples and coffee mixtures with 10% robusta coffee added to arabica coffee. Totally correct classified samples were obtained when the TAG stereospecific results of the considered coffee mixture (90 : 10 arabica/robusta) were elaborated by LDA procedure.

3.
Food Chem ; 140(4): 680-5, 2013 Oct 15.
Article in English | MEDLINE | ID: mdl-23692753

ABSTRACT

The oxidative stability of conjugated linoleic (CLA) and linoleic (LA) acids in different chemical forms (free acids, methyl esters and homogeneous triacylglycerols) was compared. All model systems were heated at 180°C for different times (15, 30, 45 and 60min). The primary oxidation products were evaluated by spectrophometric analysis, while the volatile compounds were determined by solid phase micro-extraction (SPME), coupled with gas chromatography-mass spectrometry (HRGC-MS). The isomer profile modifications were investigated by silver-ion high performance liquid chromatography (Ag(+)-HPLC) equipped with an UV detector. Generally, peroxide values decreased during the heating time. Among the volatiles, saturated aldehydes were the most represented compounds. Isomerization of cis,trans and trans,cis CLA to trans,trans isomers was observed mainly for the methyl form of CLA. The three different chemical forms of LA never showed isomerization phenomena.


Subject(s)
Linoleic Acid/chemistry , Linoleic Acids, Conjugated/chemistry , Gas Chromatography-Mass Spectrometry , Hot Temperature , Isomerism , Oxidation-Reduction
4.
J Chromatogr Sci ; 49(5): 379-83, 2011 May.
Article in English | MEDLINE | ID: mdl-21549030

ABSTRACT

This paper reports the separation of four isomers of conjugated linoleic acid (CLA), c,t/t,c-8,10; c,t/t,c-9,11; c,t/t,c-10,12; c,t/t,c-11,13, after reaction of esterification with aliphatic alcohols of different chain length and adduct formation with 4-methyl-1,2,4-triazoline-3,5-dione (MTAD). The high resolution gas chromatographic analyses were carried out using a simple 50-m cyanopropyl polysiloxane capillary column both with a flame ionization detector and a mass spectrometer. The resolution between the two pair of isomers: c,t/t,c-9,11 and c,t/t,c-10,12 and between c,t/t,c-10,12 and c,t/t,c-11,13 isomers were good for all the investigated alkyl esters and increased with the chain length of alcohol esterified to carboxylic moiety of CLA isomers. The most interesting result was relative to the c,t/t,c-8,10 and c,t/t,c-9,11 isomers, critical pair of isomers also when analyzed with a 120-m cyanopropyl polysiloxane capillary column; their resolution also increased from methyl to hexyl esters of CLA isomers and reached an acceptable value (0.8) in the case of hexyl esters. The best resolutions of the four considered CLA isomers were obtained with the hexyl esters of MTAD adducts of the isomers, without excessive analysis time. This method was useful and simple to evaluate the profile of the four main c,t isomers in commercial CLA samples.


Subject(s)
Gas Chromatography-Mass Spectrometry/methods , Linoleic Acids, Conjugated/isolation & purification , Esters/chemistry , Esters/isolation & purification , Isomerism , Linoleic Acids, Conjugated/chemistry , Triazoles/chemistry
5.
J Agric Food Chem ; 55(2): 191-6, 2007 Jan 24.
Article in English | MEDLINE | ID: mdl-17227041

ABSTRACT

In this study, sn-1,2-, sn-2,3-, and sn-1,3-diacylglycerols were isolated from olive oil, and their urethane derivatives (urethanes) were prepared. Normal-phase high-performance liquid chromatography (NP-HPLC) separation of the urethane isomers was performed and the separate classes were studied by nuclear magnetic resonance (NMR). The use of 1H NMR and homo- and heteronuclear 2D techniques provided a great amount of information in a very short time, particularly when a high-field NMR instrument (700 MHz) was used. Particularly diagnostic for this kind of compound was the glyceridic moiety that presents typical chemical shifts both for carbon and hydrogen. These studies show the usefulness of NMR spectroscopy to recognize clearly the sn-1,3- and, moreover, sn-1,2- with respect to sn-2,3-diacylglycerols, although very minor differences occur between them.


Subject(s)
Chromatography, High Pressure Liquid , Diglycerides/chemistry , Diglycerides/isolation & purification , Magnetic Resonance Spectroscopy , Plant Oils/chemistry , Urethane/chemistry , Olive Oil
6.
J Chromatogr Sci ; 38(5): 195-9, 2000 May.
Article in English | MEDLINE | ID: mdl-10813516

ABSTRACT

Nonaqueous reversed-phase high-performance liquid chromatography of 10 homogeneous triacylglycerol molecular species (TAG), both saturated and unsaturated, is carried out. The eluate from the column is detected by an ultraviolet diode array detector (DAD) on-line with an evaporative light-scattering detector (ELSD). The retention parameters (as selectivities, alpha) for 220 TAGs are determined, and the obtained values are related to the following structural parameters: total carbon number; mono-, di-, and triunsaturated fatty acid residues number/molecule; and monounsaturated fatty acid carbon number. Multiple regression analysis is carried out to obtain a relationship for the prediction of alpha values of any TAG when the same experimental conditions are used. In regard to the quantitative analysis of the separated TAG species, the dependence of response of the two on-line detectors on the aforementioned structural parameters is studied. Three different wavelengths (205, 210, and 215 nm) are considered for TAG detection by DAD; in each case, the obtained multiple regression model shows a good correlation between the dependent variable and predictive values of the TAG species (response factors and considered structural parameters, respectively). The ELSD gives responses exponentially related to injected amounts. Also, in this case, an attempt to relate the response factors of each considered detector to some structural parameters of TAG species is carried out. The results of this study are used to analyze the TAG fraction from an olive oil.


Subject(s)
Chromatography, High Pressure Liquid/methods , Triglycerides/analysis , Light , Olive Oil , Online Systems , Plant Oils/chemistry , Regression Analysis , Scattering, Radiation , Spectrophotometry, Ultraviolet
7.
West Indian med. j ; 46(Suppl.2): 40, Apr.1997.
Article in English | MedCarib | ID: med-2453

ABSTRACT

Alkaloidal cocaine (COPC) is widely sold in the West Indies in a form suitable for smoking. These little rocks called "crack", addictive in high doses (typically 120 mg), produce a rapid, intense, high and a very compelling type of COC dependence. The bioavailability and the metabolism of the smoked form (half-life of 56 min versus 78 and 80 min, respectively, after IV and IN COC administration) conduce to low levels of metabolites in serum and in urine. Clinical and forensic toxicology laboratories are more and more solicited for testing major cocaine metabolite: benzoylecgonine (BZE). The Enzyme Multiplied Immunossay Technique (EMIT) is a fast, simple and reliable technology. However, the assay cut off concentration for BZE of the commercially available kit: (EMIT dau Cocaine Metabolite Immunoassay) is too high (300ng/ml) for serum or urine detectable levels of BZE in cocaine smokers. We proposed a modified EMIT assay to make this technique suitable for level of detection. The immunoassay was applied to ROCHE COBAS MIRA Plus analyser. The increase of the sample volume up to 25 ul and the use of calibration standards 0 to 300 ng/ml conduce to a lower detection limit of 50ng/ml. The within run precision of the assay was less than 10 percent. The results were confirmed by gas chromatography mass spectrometry. The increase of sensitivity was near 30 percent. No false positive results were observed. The presented modification demonstrates the application of currently available EMIT Immunoassay to rapid and reliable testing for BZE in cocaine smokers. (AU)


Subject(s)
Humans , Substance Abuse Detection , Crack Cocaine/urine , Enzyme Multiplied Immunoassay Technique , Cocaine/urine
8.
Br J Nutr ; 68(1): 3-10, 1992 Jul.
Article in English | MEDLINE | ID: mdl-1390613

ABSTRACT

It has been shown that each individual has a considerable day-to-day variation (intra-individual variation) in his or her level of food consumption. A large intra-individual variation has adverse effects on the reliability of research studies. The effect of the intra-individual variation can be minimized by taking food intake records over several days. An increase in the number of days entails higher costs, and this could limit the practicability of the study. In the recent literature on the methodology of dietary surveys, there is a growing interest in the estimation of the number of days required to conduct a reliable dietary survey. Recent developments in statistical theory allow the problem of large intra-individual variability to be overcome. These new statistical techniques require knowledge of the intra- and inter-individual variability and the appropriate adjustment of the statistical results. The aim of the present study was to evaluate the number of days of recorded intake required to obtain an estimate of the components of variance (the inter-individual and the intra-individual variability) focusing on foods rather than nutrients.


Subject(s)
Diet Surveys , Feeding Behavior , Aged , Female , Humans , Italy , Male
9.
Int J Vitam Nutr Res ; 62(3): 273-80, 1992.
Article in English | MEDLINE | ID: mdl-1473913

ABSTRACT

The nutritional status of forty-six self sufficient institutionalized elderly people of Perugia was assessed. The diet of this group is slightly better than that of other groups of elderly people previously examined. As observed in other studies, the diet of the elderly from this region of Italy does not seem to be of the Mediterranean type. The location of subcutaneous fat in elderly men is prevalent in the upper trunk and in women in the arms. The clinical signs of nutritional status among this group of self-sufficient institutionalized elderly people are in general not specific and mostly associated with old age. The pathological conditions observed and the administration of drugs do not appear to substantially influence the nutritional status of this group.


Subject(s)
Nutritional Status , Aged , Blood Chemical Analysis , Homes for the Aged , Humans , Italy , Nutrition Surveys
11.
Int J Vitam Nutr Res ; 59(1): 40-7, 1989.
Article in English | MEDLINE | ID: mdl-2722424

ABSTRACT

Thiamin and riboflavin nutriture were assessed in 127 apparently healthy individuals aged between 20 and 82 yr, living in small villages near the town of Gubbio. The methods of erythrocyte transketolase activity and HPLC determination of thiamin pyrophosphate (TPP) for thiamin and erythrocyte glutathione reductase and HPLC determination of flavin adenine dinucleotide (FAD) for riboflavin were used. A significant correlation between enzymatic and HPLC methods was found. This was not the case for the correlation between status test and vitamin intake, particularly for thiamin. The vitamer determination in blood by HPLC can be considered a reliable, fast and reasonably accurate method for long-term thiamin and riboflavin nutritional status assessment.


Subject(s)
Nutritional Status , Riboflavin/blood , Thiamine/blood , Adult , Aged , Aged, 80 and over , Chromatography, High Pressure Liquid , Erythrocytes/enzymology , Female , Flavin-Adenine Dinucleotide/blood , Glutathione Reductase/blood , Humans , Male , Middle Aged , Thiamine Pyrophosphate/blood , Transketolase/blood
12.
Int J Vitam Nutr Res ; 58(1): 85-91, 1988.
Article in English | MEDLINE | ID: mdl-3384590

ABSTRACT

In this group of institutionalized elderly people the anthropometry and body composition situation is much better than that observed in a noninstitutionalized group examined longitudinally on a previous occasion. On the other hand, as expected, indices of physical activity are lower. The diet is in general satisfactory, considering the very low physical activity of those individuals. Only a few foods and nutrients show marginal low intakes (fish, eggs and legumes; lipids, iron, thiamin and vitamin A).


Subject(s)
Institutionalization , Nutritional Physiological Phenomena , Aged , Aged, 80 and over , Female , Humans , Italy , Male , Middle Aged , Minerals/blood , Nutrition Disorders/blood , Sex Factors , Vitamins/blood
13.
Int J Vitam Nutr Res ; 57(2): 193-202, 1987.
Article in English | MEDLINE | ID: mdl-3654113

ABSTRACT

Nutritional status (anthropometry, food habits, thiamin and riboflavin status) has been evaluated in 136 (70 males and 66 females) free living healthy elderly individuals (age range 65-69 yrs) from the district of San Carlo Arena that can be considered representative of the sociocultural and economic level of the city of Naples. By assuming as reference values those of middle aged individuals, 50 percent of elderly men and 85 percent of elderly women showed different degree of excess body fat. As far as food habits are concerned legumes, vegetables and fruit daily intake was quite high whilst alcohol consumption was low. Furthermore milk and eggs intake was low and infrequent. Although prevalence of excess body weight was high, total daily energy intake was found to be equal or slightly above dietary recommendations for the elderly. Diet composition showed a high protein intake whilst CHO and fat intake was slightly below recommendations. Micronutrients' intake was insufficient for calcium in 10 percent of both males and females and for iron in 20 percent of men and 40 percent of women. Niacin intake was low in about 50 percent of both men and women. Thiamin nutritional status was found low in 20 percent of men and women and riboflavin status in 40 percent of men and 20 percent of women. In conclusion obesity and overweight are very frequent in an urbanized sample of free living healthy elderly individuals of Naples. On the other hand serum calcium and iron and some vitamin deficiency is not uncommon. The composition of the diet seems to be also poor in some micronutrients.


Subject(s)
Aged , Nutritional Status , Body Composition , Body Height , Body Weight , Diet , Energy Intake , Feeding Behavior , Female , Humans , Italy , Male , Niacin/administration & dosage , Riboflavin/administration & dosage , Thiamine/administration & dosage
14.
Int J Vitam Nutr Res ; 56(4): 381-6, 1986.
Article in English | MEDLINE | ID: mdl-3804615

ABSTRACT

A study was conducted on the biochemical vitamin status of sixty middle class parturient women ages 20-44 and 33 newborns in the gynaecology and obstetrics ward of the Assisi Hospital, Italy. Maternal venous blood obtained immediately after delivery and mixed venous-arterial cord blood was used to assess respectively the status of the mother and the neonate for vitamin A, thiamin, riboflavin and folate. Large percentages of the women were at risk (either marginal or deficient states), for thiamin (30%), riboflavin (42%) and folate (100%). In general, even though the mothers appear to be at risk for three out of the four vitamins studied, there is no indication that the infants are also at risk. Further research must be conducted to clarify the clinical implications of hypovitaminosis in pregnant women.


Subject(s)
Nutritional Physiological Phenomena , Pregnancy/blood , Vitamins/blood , Adult , Female , Fetal Blood/analysis , Folic Acid/blood , Humans , Infant, Newborn , Italy , Riboflavin/blood , Thiamine/blood , Vitamin A/blood
15.
Int J Vitam Nutr Res ; 54(4): 355-9, 1984.
Article in English | MEDLINE | ID: mdl-6526601

ABSTRACT

The thiamin, riboflavin, vitamin C, vitamin A, folacin, and vitamin B12 nutriture was assessed in a longitudinal study in 206 aged pensioners of the city of Perugia. The prevalence of thiamin and riboflavin malnutrition, particularly in men, was rather high. Unexpectedly low values of plasma vitamin C were not uncommon among men. For folacin there were a large number of individuals with low plasma levels, while the plasma levels of vitamin A and B12 is in general satisfactory. As in other studies, no significant correlation between vitamin nutriture and intake was found.


Subject(s)
Aged , Avitaminosis/epidemiology , Nutritional Physiological Phenomena , Ascorbic Acid/blood , Diet , Female , Folic Acid/blood , Humans , Italy , Longitudinal Studies , Male , Riboflavin/blood , Sex Factors , Thiamine/blood , Vitamin A/blood , Vitamin B 12/blood
16.
Int J Vitam Nutr Res ; 54(1): 75-90, 1984.
Article in English | MEDLINE | ID: mdl-6735618

ABSTRACT

206 aged pensioners of the city of Perugia have been examined in a longitudinal study, with emphasis on body composition, diet, life habits and clinical-biochemical data. From the anthropometric data of the individuals examined in 1981 it is evident that both in men and women obesity is common especially among the women. The opposite is true for the arm muscle area. Comparing the same men examined in 1976 and 1981 body fatness decreased in the five years interval. Food and nutrient intakes are rather similar in the 1976 and 1981 surveys. Consumption of milk, eggs, fish and legumes is not high. The men, but not the women, tended to a high consumption of meat and alcoholic beverages. The intake in 1981 of thiamin, riboflavin and vitamin A seems in general to be inadequate according to our recommended values. The biochemical data show practically no difference in the two surveys. Serum cholesterol continued to be rather high for an Italian population.


Subject(s)
Aged , Nutrition Surveys , Alcohol Drinking , Body Composition , Diet Surveys , Female , Follow-Up Studies , Food , Humans , Italy , Male , Middle Aged , Obesity/epidemiology , Sex Factors , Skinfold Thickness
18.
S TA NU ; 6(5-6): 267-72, 1976.
Article in Italian | MEDLINE | ID: mdl-1037417

ABSTRACT

The determination of lipids, available carbohydrates and unavailable carbohydrates, and of various minerals has been carried out on some baby foods; the value of the protein fraction has been similarly determined by the ultrafiltration method of the enzymic hydrolisate in vitro. Both the total protein content and the essential amino acid availability of the foodstuffs are satisfactory although generally speaking a slight decrease of the protein value has been found in this material as compared to the crude samples, due particularly to the breakdown of sulfur-containing amino acids. This breakdown is due probably to the high temperature reached during the technological processes at industrial level.


Subject(s)
Dietary Proteins , Food Analysis , Infant Food/analysis , Amino Acids/analysis , Dietary Carbohydrates/analysis , Dietary Fats/analysis , Dietary Proteins/analysis , Food Preservation , Freeze Drying , Minerals/analysis
19.
S TA NU ; 6(5-6): 273-5, 1976.
Article in Italian | MEDLINE | ID: mdl-1037418

ABSTRACT

Toxic activities in various animal species have shown for rapeseed oil. In this paper the influence of this oil on lipoprotein lipase activity of heart, liver and lung of pigs has been examined. The animals were fed with rapeseed oil with 40% erucic acid for 7, 15, 20 and 40 days. The control animals received olive oil. The results have shown a slight increase in the lipoprotein lipase activity in the heart of the pig after 20 days with rapeseed oil. In the liver this increase is particularly large in the pigs having been fed for 15 days both with rapeseed oil and olive oil. No differences were observed in the lung in the test and control animals with the only exception of animals fed for 20 days.


Subject(s)
Dietary Fats , Lipoprotein Lipase/metabolism , Oils/pharmacology , Animals , Erucic Acids/pharmacology , Liver/enzymology , Lung/enzymology , Myocardium/enzymology , Swine
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