共查询到20条相似文献,搜索用时 31 毫秒
1.
Wahid Herchi Faouzi Sakouhi Sadok Boukhchina Habib Kallel Claude Pepe 《Journal of the American Oil Chemists' Society》2011,88(7):1011-1017
A comparative study was performed to determine tocopherols, tocotrienols, fatty acids, and pigments content during the development
of three varieties of flaxseed (H52, O116 and P129). Seed samples were collected at regular intervals from 7 to 56 days after
flowering (DAF). The highest content of chlorophyll (89.72–130.5 mg/kg oil) was detected at 7 DAF. The maximum level of carotenoids
(52.10–65.55 mg/kg oil) was reached at 21 DAF. During seed development, unsaturated fatty acids are the major component, reaching
85% of the total fatty acids while saturated fatty acids content were about 15%. The maximum level of γ-tocopherol (585 mg/kg
oil) was reached at 42 DAF in P129 variety. These results may be useful for evaluating the flaxseed quality and determining
its optimal harvest period. 相似文献
2.
Samia Dabbou Manel Issaoui Maurizio Servili Agnese Taticchi Samira Sifi Gian Francesco Montedoro Mohamed Hammami 《European Journal of Lipid Science and Technology》2009,111(4):392-401
The behaviour of three European olive varieties, Ascolana Tenera, Koroneiki and Picholine, cultivated in the north of Tunisia, was compared to an autochthonous variety, Chétoui. Most of the quality indices and the fatty acid composition showed significant variations between the olive oils. Among the introduced varieties, the Picholine cultivar had the highest value of oleic acid (61%) whereas the Ascolana Tenera cultivar was noteworthy for its lowest content of phenolic compounds (175 mg/kg) and presented the highest level of palmitic acid. The Chétoui variety presented a high content of oleic and linoleic acids. But all samples, both the autochthonous Chétoui and the introduced cultivars, have similar levels of antioxidant compounds, with the exception of phenols. The aroma composition showed significant differences between the oils from the foreign cultivars. The major volatile component was the C‐6 aldehyde fraction whose content varied greatly between the different varieties studied: The E‐2‐hexenal content ranged from 1.6 mg/kg of oil in the Ascolana Tenera variety to >5 mg/kg for the Picholine and Koroneiki cultivars, whereas the Chétoui variety had the lowest levels of volatile compounds, with the exception of the hexanal level which was tenfold higher than in the foreign cultivars. Therefore, our results showed that two of the introduced varieties, Koroneiki and Picholine, showed good adaptation to the Tunisian cultivation conditions. So far, we claim the possibility to develop the successful cultivation of these latter imported varieties in the country. 相似文献
3.
John Parry Zhigang Hao Marla Luther Lan Su Kequan Zhou Liangli Yu 《Journal of the American Oil Chemists' Society》2006,83(10):847-854
Cold-pressed onion, parsley, cardamom, mullein, roasted pumpkin, and milk thistle seed oils were characterized for their fatty
acid (FA) composition, tocopherol content, carotenoid profile, total phenolic content (TPC), oxidative stability index (OSI),
color, physical properties, and radical-scavenging capacities against peroxyl (oxygen radical-scavenging capacity) and stable
DPPH (diphenylpicrylhydrazyl) radicals. Parsley seed oil had the highest oleic acid content, 81 g/100 g total FA, and the
lowest saturated fat among the tested oils. Roasted pumpkin seed oil contained the highest level of total carotenoids, zeaxanthin,
β-carotene, cryptoxanthin, and lutein at 71 μmol/kg and 28.5, 6.0, 4.9, and 0.3 mg/kg oil, respectively. Onion seed oil exhibited
the highest levels of α- and total tocopherols under the experimental conditions. One of the parsley seed oils exhibited the
strongest DPPH scavenging capacity and the highest oxygen radical absorbance capacity (ORAC) value of 1098 μmol Trolox equiv/g
oil. However, ORAC values of the tested seed oils were not necessarily correlated to their DPPH scavenging capacities under
the experimental conditions. The highest TPC of 3.4 mg gallic acid equiv/g oil was detected in one of the onion seed oils.
The OSI values were 13.3, 16.9–31.4, 47.8, and 61.7 h for the milk thistle, onion, mullein, and roasted pumpkin seed oils,
respectively. These data suggest that these seed oils may serve as dietary sources of special FA, tocopherols, carotenoids,
phenolic compounds, and natural antioxidants.
An erratum to this article is available at . 相似文献
4.
Relation of days after flowering to chemical composition and physiological maturity of sunflower seed 总被引:1,自引:1,他引:0
J. A. Robertson G. W. Chapman R. L. Wilson 《Journal of the American Oil Chemists' Society》1978,55(2):266-269
Hybrid sunflower seed (achene) were collected from plants at 7-day intervals after the initiation of flowering which occurred
58 days after planting. The seed were analyzed for moisture, total oil, free fatty acids, lipid classes, and fatty acid composition.
Seed dry weight, oil and triglyceride contents were maximum 35 days after the initiation of flowering (DAF) when the seed
moisture content was about 36%. This point was defined as “physiological maturity” for sunflowers. The fatty acid composition
of the oil extracted from the seed was determined at each stage of maturity. Total saturated fatty acids were 27% at 7 DAF
and then decreased to a constant 9% by 35 DAF. At 7 DAF, linolenic acid content was 10.7% then decreased to less than 0.1%
by 28 DAF. Oleic acid was about 12% at 7 DAF, increased to 59.6% at 14 DAF, and then gradually decreased to 31.4% by 56 DAF.
On the other hand, linoleic acid was about 48% at 7 DAF, decreased to 23% by 14 DAF, but then gradually increased to 59.2%
by 56 DAF. An analysis of variance of linoleic and oleic acid contents from 21 DAF to 70 DAF showed a highly significant change
in composition with maturation time. The changes in the composition of these fatty acids from 21 DAF to 70 DAF appeared to
be related to the environmental temperature which gradually decreased until 56 DAF. Increase in free fatty acids after physiological
maturity indicated that deterioration of seed oil was beginning to occur. 相似文献
5.
Antonietta Baiano Carmela Terracone Giuseppe Gambacorta Ennio La Notte 《Journal of the American Oil Chemists' Society》2009,86(11):1083-1092
The chemical characteristics, phenolic content and antioxidant activity of olive oils flavored with garlic, lemon, oregano,
hot pepper, and rosemary were evaluated during 9 months of storage. At the end of the storage period, the unflavored and the
garlic-flavored oils maintained their chemical parameters within the limits fixed for extra-virgin olive oils. After 9 months
of storage, a noticeable decrease in phenolic content was observed in all the oils. The highest (35.0 ± 3.9 mg/kg oil) and
the lowest (6.3 ± 0.4 mg/kg) phenolic contents were detected in the unflavored and garlic-flavored oils, respectively. Compounds
such as 3,4-DHPEA-EDA (3,4-dihydroxyphenylethyl 4-formyl-3-formylmethyl-4-hexenoate, the dialdehydic form of decarboxymethyl
elenolic acid linked to hydroxytyrosol) and p-HPEA-EDA (dialdehydic form of the decarboxymethyl elenolic acid linked to tyrosol) were the most abundant in both unflavored
and lemon-flavored oils up till 6 months of storage. At the end of the storage period, increases in 3,4-DHPEA (hydroxytyrosol)
and p-HPEA (tyrosol) were measured in almost all the oils. During storage, the antioxidant activity coefficients of the phenolic
extracts, calculated according to the β-carotene bleaching assay, significantly decreased and, after 9 months, were in a decreasing
order: rosemary (51.3 ± 4.2), hot pepper, lemon, oregano, unflavored, and garlic (8.5 ± 0.7). 相似文献
6.
Dwiecki K Siger A Czubiński J Nogala-Kałucka M Lampart-Szczapa E 《Journal of the American Oil Chemists' Society》2012,89(3):379-387
The focus of the present research was to study inhibition of lipoxygenase activity by rapeseed native polyphenols and the
interactions between those compounds and the enzyme. The enzyme and polyphenolic compounds (polyphenols, phenolic acids) were
extracted from rapeseed (Brassica napus) varieties Aviso and PR45DO3. The total phenolic compounds concentration in tested rapeseed was 1,485–1,691 mg/100 g d.m. (dry matter) and the free phenolic
acids content in both rapeseed varieties was about 76 μg/100 g d.m. The isolated proteins showed lipoxygenase activity. Prooxidant
properties of phenolic compounds in the presence of lipoxygenase and linoleic acid were observed rather in the case of extracts
containing a relatively high concentration of miscellaneous polyphenols. Antioxidant properties were recorded in the case
of phenolic acid extracts which contain only 1.4–1.9% of phenolics present in raw phenolic extracts. We propose that the prooxidant
effect of phenolic compounds comes from quinone and oxidized polyphenols formation. The observed antioxidant activity of phenolic
acid extracts is probably due to their ability to scavenge free radicals formed from linoleic acid. However, reduction of
lipoxygenase ferric to ferrous ions, which prevent the activation of the enzyme and inhibited its activity, was also observed. 相似文献
7.
Paula Jimenez Lilia Masson Andrés Barriga Jorge Chávez Paz Robert 《European Journal of Lipid Science and Technology》2011,113(4):497-505
The effect of the addition of olive leaf (Olea europaea, cv. Arbequina) extracts, i.e. hydroalcoholic (ethanol–water 1:1; OHE), juice (OJ) and supercritical fluid‐CO2 (OSFE) on the oxidative stability of vegetable oils with different unsaturation, such as soybean oil (SBO), canola oil (CO) and high oleic sunflower oil (HOSO), were studied at two concentrations (250 and 630 mg/kg oil, expressed as caffeic acid equivalent (CAE)). The extracts were characterized by the total phenolic content (Folin–Ciocalteau method), phenol chromatographic profiles (LC‐MS) and antioxidant activity (DPPH). OHE showed the highest phenol content (7.7 mg CAE/mL) while OJ and OSFE showed values of 5.4 and 2.2 mg CAE/mL, respectively. Oleuropein and its derivatives were the major phenolic compounds identified in OHE. The addition of 630 mg CAE/kg oil of OHE and OSFE to HOSO, SBO and CO showed an antioxidant effect, increasing significantly the induction time (IT) (p<0.05). That effect was highest when the system was more monounsaturated. In contrast, OJ showed a pro‐oxidant effect for all oils systems for both concentration studied. This behaviour could be attributed to the diphenol oxidase (PPO) activity. 相似文献
8.
Effect of Extraction Method on the Phenolic and Cyanogenic Glucoside Profile of Flaxseed Extracts and their Antioxidant Capacity
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Katarzyna Waszkowiak Anna Gliszczyńska-Świgło Veronique Barthet Joanna Skręty 《Journal of the American Oil Chemists' Society》2015,92(11-12):1609-1619
The application of flaxseed extracts as food ingredients is a subject of interest to food technologists and nutritionists. Therefore, the influence of the extraction method on the content and composition of beneficial compounds as well as anti‐nutrients is important. In the study, the effects of two solvent extraction methods, aqueous and 60 % ethanolic, on phenolic and cyanogenic glucoside profiles of flaxseed extract were determined and compared. The impact of extracted phenolic compounds on the antioxidant capacity of the extracts was also investigated. Defatted meals from brown and golden flax varieties were used as extraction material. The ethanolic extraction was more selective for phenolics (100.8–131.7 mg g?1) than the aqueous one (11.5–15.7 mg g?1). However, the contribution of particular phenolic compounds to total phenolics was much more dependent on flax variety than extraction method. A strong relationship was observed between both radical scavenging and ferric reducing activity and the content of phenolics (particularly secoisolariciresinol diglucoside). The correlation between extract chelating ability and phenolics was moderate suggesting that other flaxseed compounds are involved in this activity. The extraction method strongly affected cyanogenic glucoside content of flaxseed extracts; the aqueous extraction caused 96 % reduction in cyanogenic glucoside content (0.56–0.62 mmol g?1) when compared to the content in defatted meal (9.1–11.6 mmol g?1). On the contrary, ethanolic extraction resulted in the high cyanogenic glucoside content in the extracts (71–89 mmol g?1). The results reveals that ethanolic extraction gives extracts rich in antioxidant lignans; aqueous extracts have lower antioxidant activity than ethanolic but cyanogenic glucosides are significantly reduced. 相似文献
9.
Effects of Variety,Maturation and Growing Region on Chemical Properties,Fatty Acid and Sterol Compositions of Virgin Olive Oils
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Dilsat Bozdogan Konuskan Burcu Mungan 《Journal of the American Oil Chemists' Society》2016,93(11):1499-1508
Chemical properties, fatty acid and sterol compositions of olive oils extracted from Gemlik and Halhal? varieties grown in Hatay and Mardin provinces in Turkey were investigated during four maturation stages. The olive oil samples were analyzed for their chemical properties such as free acidity, peroxide value, total carotenoid, total chlorophyll, total phenolic contents, antioxidant activity, fatty acid and sterol compositions. Chemical properties, fatty acids and sterol profiles of olive oil samples generally showed statistically significant differences depending on the varieties, maturation and growing areas (p < 0.05). As free fatty acid contents and total phenolic contents increased, total carotenoid and chlorophyll contents decreased throughout the maturity stages. Total carotenoid and chlorophyll contents of oil samples from Mardin were higher than those of Hatay. The total phenolic compounds of olive oil samples ranged from 20.62 in Gemlik to 525.22 mg GAE/kg oil in Halhal? from Hatay. In general, the phenolic contents and antioxidant activities of olive oil samples were positively associated. Oleic acid content was the highest 71.53 % in H1 samples in Hatay. Total sterol contents were 1194.33 mg/kg in Halhal? and 2008.66 mg/kg in Gemlik from Hatay. Stigmasterol contents of oils obtained from Hatay were lower than those of Mardin. Oleic acid, palmitic acid, β‐sitosterol, ?‐5‐avenasterol and campesterol contents fluctuated with maturation for each of variety from both growing regions. These results showed that the variety, growing area and maturation influence the chemical properties, fatty acid and sterol compositions. 相似文献
10.
Sylwester Czaplicki Dorota Ogrodowska Dorota Derewiaka Małgorzata Tańska Ryszard Zadernowski 《European Journal of Lipid Science and Technology》2011,113(12):1456-1464
The aim of the research was to characterize bioactive components of unsaponifiable fraction of selected unconventional oils. Nine oils were analyzed as far as the content of tocopherols, squalene, phenolic compounds, and sterols were concerned. Tocopherols and squalene were analyzed by HPLC coupled with diode array detector and fluorescent detector (HPLC‐DAD‐FLD). The content of sterols in oils was determined by GC coupled with MS (GC‐MS). The total amount of phenolic compounds in oils was determined by the colorimetric methods using Folin–Ciocalteau phenol reagent. The examined oils were characterized by differentiated amount of particular forms of tocopherols. The oil obtained from the seeds of amaranth was the richest source of squalene (over 52 mg/g oil). The presence of 22 different compounds of sterols were identified, whereas β‐sitosterol was found in the largest amount. Total amount of sterols in the oils ranged from 90 (walnut) to 850 mg/100 g (evening primrose). Significant differentiation of total amount of phenolic compounds was observed in the examined oils. Evening primrose oil showed the highest amount of phenolic compounds (679 mg/kg). The presented results prove that plant oils obtained from nonconventional sources are a potential source of bioactive compounds. 相似文献
11.
Huri Ilyasoglu Beraat Ozcelik Vera Van Hoed Roland Verhe 《Journal of the American Oil Chemists' Society》2010,87(6):627-636
This study presents a combined approach of establishing cultivar differences between Aegean olive oils, obtained from economically
important olive oil producing cultivars (cv. Ayvalik and Memecik), based on chemometric evaluation of their content and in
particular composition of the minor compounds. Evaluation of minor compounds with principal component analysis and linear
discriminant analysis (LDA) indicated differentiation according to the cultivars. LDA produced a 100% correct group classification.
Moreover, stigmasterol, apparent β-sitosterol and total sterols were found to have the highest discriminating power. Memecik
oils were characterized by the highest content of antioxidant compounds (α-tocopherol, phenolic compounds and total phenolic
compounds). On the other hand, Ayvalik oil had the highest level of total sterols. The data were analyzed statistically to
evaluate the differences according to variety and crop season. The minor compounds of Ayvalik and Memecik oils presented statistically
significant differences (p < 0.01) according to variety, except for the hydroxytyrosol and clerosterol content. The amount of α-tocopherol, total phenolic
compounds, apparent β-sitosterol and total sterols varied with respect to crop season. A good correlation was observed between
the amount of α-tocopherol, total phenolic compounds, apparent β-sitosterol and total sterols and some climatic variables. 相似文献
12.
Wei Qiong Yuan Jian Zhong Hu Li Qiang Yin Zhao Lin Lv 《Journal of the American Oil Chemists' Society》2021,98(5):531-540
The ability of soil and water conservation crops to resist stress is closely related to their abundance of lipid-soluble chemical components. This study systematically evaluated the composition and content of fatty acids, sterols, squalene, and tocopherol in oils extracted from three varieties of crops growing on the Chinese Loess Plateau with extreme environments. The dominant fatty acids in the wild seabuckthorn pulp oil were oleic acid (29.73%), palmitic acid (26.83%), and palmitoleic acid (25.71%), and those in wild seabuckthorn seed oil were linoleic acid (42.29%), α-linolenic acid (20.65%), and oleic acid (18.94%). The most abundant fatty acids in wild elaeagnusmollis seed oil were oleic acid (43.29%), linoleic acid (35.93%), and α-linolenic acid (7.00%). Wild yellowhorn seed oil was rich in linoleic acid (34.14%), oleic acid (25.99%), and erucic acid (8.76%). Seabuckthorn seed oil had the highest levels of total sterols (619.33 mg/100 g), followed by seabuckthorn pulp oil (606.10 mg/100 g), yellowhorn seed oil (249.46 mg/100 g), and elaeagnusmollis seed oil (224.01 mg/100 g). However, the squalene content was highest in elaeagnusmollis seed oil (68.06 mg/100 g) and similarly low in yellowhorn seed oil (9.81 mg/100 g), seabuckthorn pulp oil (4.62 mg/100 g) and seabuckthorn seed oil (4.71 mg/100 g). In addition, seabuckthorn pulp oil had the highest tocopherol content (179.92 mg/100 g), followed by seabuckthorn seed oil (130.57 mg/100 g), elaeagnusmollis seed oil (85.87 mg/100 g), and yellowhorn seed oil (45.44 mg/100 g). This study provides favorable data supporting biomass resource utilization and organic synthesis of bioactive raw chemical composition. 相似文献
13.
Intidhar Bouali Hajer Trabelsi Ikram Bou Abdallah Ali Albouchi Lucy Martine Stéphane Grégoire Ghaith Bouzaien Mhemmed Gandour Sadok Boukhchina Olivier Berdeaux 《Journal of the American Oil Chemists' Society》2013,90(12):1869-1876
Among oil compounds, fatty acids, tocopherols and xanthophylls (lutein and zeaxanthin) are of special interest due to their nutritional properties. The identification and quantification of these compounds in pecan nuts (Carya illinoinensis) could therefore be very useful to produce functional foods rich in compounds of this type. This paper reports studies on their accumulation and the effect of ripening on the content of these high value-added compounds. The total lipid content increased during the ripening. Saturated and polyunsaturated fatty acids decreased significantly, whereas, monounsaturated fatty acids increased during the ripening of pecan nut fruit. Maximum levels of total tocopherol (279.53 mg/kg oil) and xanthophyll (6.18 mg/kg oil) were detected at 20th weeks after the flowering date. These amounts decreased gradually as ripening advances. The early stages of pecan ripening seem to have nutritional and pharmaceutical interests. These results may be useful for evaluating the pecan nut quality and determining the optimal period when the pecans accumulated the maximum of these nutritional and healthy compounds. 相似文献
14.
Iago Hudson da Silva Souza Juliete Pedreira Nogueira Murugan Rajan Maria Terezinha Santos Leite Neta Narendra Narain 《European Journal of Lipid Science and Technology》2021,123(2):2000163
Babassu oil has high concentrations of phenolic compounds. When seeds are preheated, these compounds tend to migrate to the oil depending on the degree of roasting applied. This study aims to optimize the roasting conditions of babassu seeds using response surface methodology (RSM) and the desirability functions. A central composite rotational design (CCRD) is employed to investigate the effects of two independent variables, temperature (X1) and roasting time (X2) which significantly affected response variables, namely yield (%), total phenolics content (TPC), number of phenolic compounds, oxygen radical absorbance capacity, acid value and peroxide value. The quadratic model is adjusted for most responses. The roasting temperature of 222 °C and the roasting time of 43 min are standardized as ideal conditions. Thus, the oil produced at the optimized conditions shows a yield of 54.47% and TPC of 91.53 mg GAE/100 g. In the control oil sample, the presence of phenolic compounds analyzed by HPLC-DAD is not observed while under optimized conditions, seven phenolic compounds are observed. The model of optimized conditions shows a good correlation between the predicted and experimental values. In general, these results demonstrate the effectiveness of optimum roasting conditions in improving the quality of bioactive compounds in babassu oil. Practical Applications : This work aims to optimize the babassu seeds roasting process to obtain oil with a greater number of phenolic compounds and better antioxidant capacity. As the first study on babassu seeds roasting, it contributes to the generation of important data in relation to the identification and quantification of phenolic compounds in the oil. Finally, the optimum roasting conditions established in this work can be explored commercially in babassu oil extraction. 相似文献
15.
Chemical analyses performed on the invasive weed Phytolacca americana (pokeweed) growing in industrially contaminated (Ulsan) and noncontaminated (Suwon) sites in South Korea indicated that the
levels of phenolic compounds and various elements that include some heavy metals (Al, As, B, Cd, Co, Cu, Fe, Mn, Ni, Pb, and
Zn) were statistically higher in Ulsan soils compared to Suwon soils with Al being the highest (>1,116 mg/l compared to 432 mg/l).
Analysis of metals and nutrients (K, Na, Ca, Mg, Cl, NH4, N, P, S) in plant tissues indicated that accumulation occurred dominantly in plant leaves with Al levels being 33.8 times
higher in Ulsan plants (PaU) compared to Suwon plants (PaS). The ability of PaU and PaS to tolerate stress was evaluated under
controlled conditions by varying atmospheric CO2 and temperature and soil pH. When grown in pH 6.4 soils, the highest growth rate of PaU and PaS plants occurred at elevated
(30°C) and non-elevated (25°C) temperatures, respectively. Both PaU and PaS plants showed the highest and lowest growth rates
when exposed to atmospheric CO2 levels of 360 and 650 ppm, respectively. The impact of soil pH (2–6.4) on seed germination rates, plant growth, chlorophyll
content, and the accumulation of phenolics were measured to assess the effects of industrial pollution and global-warming-related
stresses on plants. The highest seed germination rate and chlorophyll content occurred at pH 2.0 for both PaU and PaS plants.
Increased pH from 2–5 correlated to increased phenolic compounds and decreased chlorophyll content. However, at pH 6.4, a
marked decrease in phenolic compounds, was observed and chlorophyll content increased. These results suggest that although
plants from Ulsan and Suwon sites are the same species, they differ in the ability to deal with various stresses. 相似文献
16.
Kostas Kiritsakis M. G. Kontominas C. Kontogiorgis D. Hadjipavlou-Litina A. Moustakas A. Kiritsakis 《Journal of the American Oil Chemists' Society》2010,87(4):369-376
The olive leaf phenolic composition of the Greek cultivars koroneiki, megaritiki and kalamon was determined using LC/MS. Furthermore, the antioxidant activity of olive leaf extracts from the above three cultivars,
using solvents of increasing polarity (petroleum ether, dichloromethane, methanol and methanol/water: 60/40) was evaluated
using the stable free radical diphenylpicrylhydrazyl (DPPH) test. Furthermore the oxidative stability index (OSI) was compared
to that of the synthetic antioxidant TBHQ and commercial oleoresin (rosemary extract). The ability of phenolic compounds to
inhibit the lipoxygenase (LOX) activity was also investigated. The ten main components determined in the olive tree leaf extracts
for the cultivars koroneiki and kalamon were: secologanoside, dimethyloleuropein, oleuropein diglucoside, luteolin-7-O-glucoside, rutin, oleuropein, oleuroside, quercetin, ligstroside and verbascoside. Respective compounds for the cultivar
megaritiki were: secologanoside, dimethyloleuropein, oleuropein diglucoside, luteolin7-O-glucoside, oleuropein, oleuroside, quercetin and ligstroside. In all three cultivars, oleuropein represented the main phenolic
component. The solvent polarity influenced the total amount of the phenolic compounds determined. When methanol/water (60/40)
was used, as solvent, more phenolic compounds were determined. The total amounts of phenols determined in the extracts, obtained
by successive extractions using the above solvents, were 6,094, 5,579 and 6,196 mg/kg (mg gallic acid/kg dried olive leaves)
for the cultivars megaritiki, kalamon and koroneiki, respectively. Among all extracts, methanol/water extracts exhibited the highest antioxidant activity as shown through the
application of the DPPH and OSI methods. The OSI antioxidant activity followed the sequence: synthetic antioxidant TBHQ > commercial
oleoresin > olive tree leaf extracts > control. Likewise, methanol/water olive leaf extracts significantly inhibited soybean
lipoxygenase, although some small differences in the activity among the olive leaf extracts of the different cultivars were
observed. The solvent polarity as well as the amount of the extract influenced the inhibitory activity. A positive correlation
was shown between the antioxidant activity of leaf extracts and the total phenol content. 相似文献
17.
Chemical Properties of Virgin Coconut Oil 总被引:1,自引:0,他引:1
A. M. Marina Y. B. Che Man S. A. H. Nazimah I. Amin 《Journal of the American Oil Chemists' Society》2009,86(4):301-307
A study on the commercial virgin coconut oil (VCO) available in the Malaysian and Indonesian market was conducted. The paper
reported the chemical characteristics and fatty acid composition of VCO. There was no significant difference in lauric acid
content (46.64–48.03%) among VCO samples. The major triacylglycerols obtained for the oils were LaLaLa, LaLaM, CLaLa, LaMM
and CCLa (La, lauric; C, capric; M, myristic). Iodine value ranged from 4.47 to 8.55, indicative of only few unsaturated bond
presence. Saponification value ranged from 250.07 to 260.67 mg KOH/g oil. The low peroxide value (0.21–0.57 mequiv oxygen/kg)
signified its high oxidative stability, while anisidine value ranged from 0.16 to 0.19. Free fatty acid content of 0.15–0.25
was fairly low, showing that VCO samples were of good quality. All chemical compositions were within the limit of Codex standard
for edible coconut oil. Total phenolic contents of VCO samples (7.78–29.18 mg GAE/100 g oil) were significantly higher than
refined, bleached and deodorized (RBD) coconut oil (6.14 mg GAE/100 g oil). These results suggest that VCO is as good as RBD
coconut oil in chemical properties with the added benefit of being higher in phenolic content. 相似文献
18.
Haiyan Li Jun Wu Curtis B. Rempel Usha Thiyam 《Journal of the American Oil Chemists' Society》2010,87(9):1081-1089
Supercritical fluid extraction (SFE) with carbon dioxide was used to extract oil from canola press cake. Different operating
conditions, e.g. pressure, temperature, and co-solvent % were investigated to optimize extraction parameters to yield canola
meal with <4% oil. The residual oil content in the extracted canola meal reduced to 2.1–2.9% in our experimental trials. Residues
of the optimum conditions based on oil yield were compared for the total phenolic content and the main phenolic compounds.
Sinapine (the choline ester of sinapic acid) was the major phenolic constituent in both the SFE and n-hexane extracted canola meals and press cakes. n-Hexane extracted residues showed the retention of the highest sinapic acid, sinapine, sinapoyl glucose and total phenolic
contents (mg/g) while the SF-extracted residues showed the lowest values for these compounds. 相似文献
19.
Barbara Garcia Júlia Magalhães Giuseppe Fregapane María Desamparados Salvador Fátima Paiva‐Martins 《European Journal of Lipid Science and Technology》2012,114(9):1070-1082
The effect of cultivar and ripeness stage on the potential nutritional value of monovarietal extra virgin olive oils (MEVOOs) obtained from Cordovil, Carrasquinha, Verdeal, and Negrinha do Freixo cultivars was investigated. MEVOOs produced were characterized by high oleic acid (72–83%), tocopherol (182–530 mg/kg), and phenolic compounds (326–1110 mg/kg) content and by a similar polyphenolic profile. 1‐Penten‐3‐one was found to be the compound with the highest contribution for the aroma of the four MEVOO, related to bitter, pungent, and leaf attributes. MEVOO from Verdeal cultivar showed the best performance in terms of the composition: the highest yield of oil, the highest content of oleic acid, high tocopherol, polyphenol and sterol content, and the lowest content of linoleic acid. These characteristics give to these MEVOO not only a great oxidative stability but also interesting properties from the health point of view. MEVOO obtained with fruits at the maturity index of around 4 were in general richer in beneficial minor compounds. MEVOO produced were discriminated by variety and ripeness stage, using a stepwise linear discriminant analysis. This discrimination will in the future enable the prevention of adulteration of these monovarietal olive oils with specific nutritional composition with other olive oils. Practical implications: High‐quality MEVOOs have recently been introduced in the market, which for growers is a practical way to differentiate and increase the commercial value of extra virgin olive oil. The quantification of major and minor olive oil compounds in monovarietal olive oils represents an objective way of predicting the sensory characteristics, stability, and potential health benefits of the oils, as well as preventing their adulteration with other olive oils. This study will help in the selection of olive varieties during the maintenance or development of new olive orchards and also to select optimum harvest period for these varieties, in order to obtain MEVOOs with the maximum quality and health benefits for consumers. 相似文献
20.
Sepideh Haghighat Kharazi Reza Esmaeilzadeh Kenari Zeinab Raftani Amiri Maryam Azizkhani 《Journal of the American Oil Chemists' Society》2012,89(7):1241-1247
The aim of this study is to describe the physicochemical properties of Iranian virgin olive oil (Zard, Mari and Phishomi)
cultivated in Roodbar, Gilan. There were statistically significant differences for most of the parameters (P < 0.05). The acidity and peroxide value were in the limit established for classification as extra virgin olive oil. The oil
of Zard had the highest amount of monounsaturated fatty acids followed by Mari and Phishomi oils. Mari oil proved to have
the minimum value of polyunsaturated fatty acids, and the highest amount of phenolic compounds and oxidative stability. The
oil of Phishomi had the maximum amount of chlorophylls and carotenoids and therefore it had the highest color index. There
were no significant differences between the cultivars regarding the refractive index (1.469 at 20 °C for all three cultivars).
According to the high content of monounsaturated fatty acids, the lowest amounts of polyunsaturated fatty acids and the highest
amounts of phenolic compounds as well as the results of a Rancimat assay, it seems that the quality of the oil of Mari cultivar
is better than Zard and Phishomi oils and is also more stable against oxidation. 相似文献