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The aim of this investigation is to compare the physicochemical properties and chemical composition of Phoenix canariensis seed oil at different stages of seed date ripening. It was demonstrated that the saponification number of the oil increases during the maturation from 179.24 to 191.28 (mg KOH/g of oil), whereas the seed oil yield, the iodine number, the p-anisidine value, the peroxide value, the acidity and the unsaponifiable matter decrease from 14.73% to 10.36%, from 89.37 to 76.66 (g/100 g of oil), from 5.51 to 3.67, from 17.66 to 3.62 (mequiv. O2/kg of oil), from 1.49% to 0.59% and from 2.72% to 1.77%, respectively. The tocol content increases as the maturity advanced. The percentages of sterols show continuous changes during ripening. The saturated fatty acid content increases throughout the ripening process. The oleic fatty acid content decreases during the seeds maturation, but increases at the end, whereas linoleic acid content initially shows an increase, and then a decrease. The total phosphorus content decreases during the period of ripening. The three samples of the seed oil show a high kinetic stability during the heating and cooling, as characterised by the differential scanning calorimetry (DSC). The DSC curves reveal an increase in the melting point from −7.73 °C to 3.71 °C but the melting enthalpy remains the same, 62.06 J/g, during the ripening of the dates. 相似文献
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Imededdine Arbi Nehdi Hassen SbihiChin Ping Tan Hedi ZarroukMutassim Ibrahim Khalil Saud Ibrahim Al-Resayes 《Industrial Crops and Products》2012,36(1):54-58
The chemical composition, main physicochemical properties and thermal stability of oil extracted from Acacia senegal seeds were evaluated. The oil, moisture and the ash contents of the seeds were 9.80%, 6.92% and 3.82%, respectively. Physicochemical properties of the oil were iodine value, 106.56 g/100 g of oil; saponification value, 190.23 mg KOH/g of oil; refractive index (25 °C), 1.471; unsaponifiable matter, 0.93%; acidity, 6.41% and peroxide value, 5.43 meq. O2/kg of oil. The main fatty acids in the oil were oleic acid (43.62%) followed by linoleic acid (30.66%) and palmitic acid (11.04%). The triacylglycerols (TAGs) with equivalent carbon number ECN 44 (34.90%) were dominant, followed by TAGs ECN 46 (28.19%), TAGs ECN 42 (16.48%) and TAGs ECN 48 (11.23%). The thermal stability analysed in a normal oxidizing atmosphere showed that the oil decomposition began at 268.6 °C and ended at 618.5 °C, with two stages of decomposition at 401.5 °C and 576.3 °C. According to these results, A. senegal seed oil has physicochemical properties, fatty acids composition and thermal characteristics that may become interesting for specific applications in several segments of food and non-food industries. 相似文献
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Studies were conducted on the properties of seeds and oil extracted from Maclura pomifera seeds. The following values (on a dry-weight basis) were obtained for M. pomifera seed, respectively: moisture 5.88%, ash 6.72%, oil 32.75% and the high protein content 33.89%. The carbohydrate content (20.76%) can be regarded as a source of energy for animals if included in their diets. The major nutrients (mg/100 g oil) were: potassium (421.65), calcium (218.56) and magnesium (185.00). The physicochemical properties of the oil include: the saponification number 174.57; the iodine value 141.43; the p-anisidine value 1.86; the peroxide value 2.33 meq O2/kg; the acid value 0.66; the carotenoid content 0.59 mg/100 g oil; the chlorophyll content 0.02 (mg/100 g oil) and the refractive index 1.45. Polymorphic changes were observed in thermal properties of M. pomifera seed oil. This showed absorbency in the UV-B and UV-C ranges with a potential for use as a broad spectrum UV protectant. The main fatty acids of the crude oil were linoleic (76.19%), oleic (13.87%), stearic (6.76%) and palmitic acid (2.40%). The polyunsaturated triacylglycerols (TAGs) LLL, PLL, POL + SLL, OLL, OOL (L: linoleic acid, O: oleic, P: palmitic acid and S: stearic acid) acids were the major TAGs found in M. pomifera seed oil. A relatively high level of sterols making up 852.93 mg/100 g seed oil was present. The sterol marker, β-sitosterol, accounted for 81% of the total sterol content in the seed oil and is followed by campesterol (7.4%), stigmasterol (4.2%), lupeol (4.1%) and Δ5-avenesterol (3.2%). The seed oil was rich in tocopherols with the following composition (mg/100 g): α-tocopherol 18.92; γ-tocopherol 10.80; β-tocopherol 6.02 and δ-tocopherol 6.29. The results showed that M. pomifera seed oil could be used in cosmetic, pharmaceutical and food products. 相似文献
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Vision-restricting "polypeepers" have been reported to result in higher egg production with improved food utilisation in hens. In the present experiments behavioural explanations of these effects were sought. For detailed observations 128 White Leghorn X Black Australorp hens were used and for pecking damage comparisons a further 192 hens. Half were fitted with polypeepers. Birds were studied in individual cages, three-bird cages or deep litter pens by direct observation and cine-camera. Adjustment problems in feeding, stereotypic head shaking and protracted displacement neck preening occurred initially after fitting of polypeepers. Disappearance of these phenomena after about one month, however, indicated adaptation. The initial reduction of egg production associated with polypeepers, observed by others, coincided with the period of adaptation. Polypeepers resulted in less activity; birds in multiple cages and litter pens resting more, while in single cages body movement was reduced. Polypeepers caused faster eating and less wastage of both pellets and mash. In general, agonistic acts were greatly reduced in multiple cages, resulting in reduced feeding competition. Polypeepers reduced significantly the incidence of feather pecking, resulting in considerably less feather loss after three months, and more so after 14 months in lay. Over the study as a whole the reductions in activity, food spillage, agonistic behaviour and feather damage probably contribute to the lower food consumption and improved laying efficiency previously reported. 相似文献
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Anarjan N Tan CP Ling TC Lye KL Malmiri HJ Nehdi IA Cheah YK Mirhosseini H Baharin BS 《Journal of agricultural and food chemistry》2011,59(16):8733-8741
A simplex centroid mixture design was used to study the interactions between two chosen solvents, dichloromethane (DCM) and acetone (ACT), as organic-phase components in the formation and physicochemical characterization and cellular uptake of astaxanthin nanodispersions produced using precipitation and condensation processes. Full cubic or quadratic regression models with acceptable determination coefficients were obtained for all of the studied responses. Multiple-response optimization predicted that the organic phase with 38% (w/w) DCM and 62% (w/w) ACT yielded astaxanthin nanodispersions with the minimum particle size (106 nm), polydispersity index (0.191), and total astaxanthin loss (12.7%, w/w) and the maximum cellular uptake (2981 fmol/cell). Astaxanthin cellular uptake from the produced nanodispersions also showed a good correlation with their particle size distributions and astaxanthin trans/cis isomerization ratios. The absence of significant (p > 0.05) differences between the experimental and predicted values of the response variables confirmed the adequacy of the fitted models. 相似文献
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The genetic diversity and population structure of two Tunisian Thymus species (Thymus algeriensis and Thymus capitatus), from 46 natural populations growing in six bioclimates, were analysed by starch gel electrophoresis using eight isozymes. The genetic diversity within populations varied at species level. Variation in T. algeriensis was higher than that observed for T. capitatus, and exclusive alleles were detected for the two studied species. A high differentiation among populations, for each species, estimated by Wright's F-statistics was revealed. In each species, a high level of inbreeding within populations induced by Wahlund effect was observed. A relatively high level of differentiation associated with a restricted gene flow among species was revealed. The PCA and UPGMA analysis, performed on all populations, showed two distinct groups with respect of specific differentiation level. The high genetic divergence between the two species corroborates their taxonomic status, as previously reported using morphological traits. The strategy for the management and conservation of populations should be made for each taxa according to its level of diversity and bioclimate. 相似文献
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Walid Elfalleh Hédia Hannachi Arbi Guetat Nizar Tlili Ferdaous Guasmi Ali Ferchichi Ma Ying 《Genetic Resources and Crop Evolution》2012,59(6):999-1014
In the present study, free amino acids and seed protein contents of pomegranate germplasm from Tunisia and China were conducted using Hitachi L8800 amino acid analyzer, Bradford and Kjeldahl methods. The work offers more consideration to protein pomegranate seeds which can be with great importance regarding the nutritive seed value of this crop. In other hand, the protein and amino acids contents were used to compare the Tunisian and Chinese pomegranate cultivars based on multivariate analyses (principal component and clustering analyses). Results show that the Tunisian and Chinese pomegranate seeds were rich in storage proteins independently of organoleptic taste as sweet, sour sweet or sour. Qualitatively, the storage protein and free amino acids of pomegranate seeds were identical. Besides, the segregation of Chinese and Tunisian pomegranate cultivars into three groups was reveled based on high, low or moderate amino acids contents. Statistically, the differences between organoleptic groups (sweet, sour sweet and sour) were not significant (P?<?0.05). However, the differences between pomegranate cultivars were statistically significant within groups. The separation of cultivars is independent to the organoleptic taste neither the geographical origin. 相似文献
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