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101.
Beibei Zhao Hua Li Tao Lan Di Wu Zhicheng Chen 《Journal of the American Oil Chemists' Society》2019,96(5):523-533
This work focused on physicochemical property assaying, fatty acid composition, triacylglycerol (TAG) profiles, and unsaponifiable matter composition of the Chinese Moringa oleifera seed oil. The results indicated that there was no significant difference in approximate nutritional components between M. oleifera seeds from China and India, while variations in the mineral element contents are significant. Both the Soxhlet extraction method and the aqueous enzymatic extraction method were adopted to extract oil from Chinese M. oleifera seeds. Oil yield obtained using the Soxhlet extraction method was higher than that obtained using the aqueous enzymatic extraction method. While both the iodine value and unsaponifiable matter content of the aqueous enzymatic extracted oil were a little higher than that of the Soxhlet extracted oil. Both oils possess a very low acid value and peroxide value, suggesting their good quality as edible oil. Fatty acid composition results indicated that this oil was especially high in oleic acid. Characterization of the TAG composition was achieved by a two-dimensional high-performance liquid chromatography (HPLC) coupling of nonaqueous reverse-phase and silver ion HPLC with the atmospheric pressure chemical ionization mass spectrometry method. A total of 22 TAG including 16 regioisomers were determined. Composition results of unsaponifiable matters revealed that this oil possesses a number of phytosterols, in which β-sitosterol and stigmasterol are most predominant. 相似文献
102.
研究糖茶藨籽油的脂肪酸和不皂化物成分。采用气相色谱-质谱联用法对糖茶藨籽油脂肪酸和不皂化物成分进行分析和鉴定。结果表明:糖茶藨籽油中共鉴定出13种脂肪酸,不饱和脂肪酸占(86.88±0.53)%,其中主要的不饱和脂肪酸为亚油酸、亚麻酸和油酸,相对含量分别为(29.06±1.08)%、(25.85±0.79)%和(19.08±0.76)%;糖茶藨籽油的不皂化物以植物甾醇和萜类化合物为主,其中植醇含量最高,达(40.42±2.54)%,其次为β-谷甾醇。 相似文献
103.
Jane Roche Zephirin Mouloungui Muriel Cerny Othmane Merah 《International Journal of Food Science & Technology》2016,51(8):1820-1826
This study was carried out to compare the kinetic accumulation of bioactive lipids during seed development in three oil crops rapeseed, sunflower and woad. Field experiments were conducted under organic conditions during 3 years. After flowering, seeds were collected each 4–5 days until harvest. The three species differed by the quantity and quality of both fatty acids and sterols. Higher levels of phytosterols and fatty acids were reached between 20 and 40 days after flowering (DAF) in sunflower, 40 and 60 DAF in rapeseed and 25 and 45 DAF for woad. The modification of lipid composition during the grain filling depends on species. Knowledge of the composition and accumulation of fatty acids and phytosterols in sunflower, rapeseed and woad seeds would assist in efforts to achieve industrial applications. These seeds may give an interesting source of bioactive lipids. 相似文献
104.
Man‐Li Zhao Jiang‐Ning Hu Xue‐Mei Zhu Hong‐Yan Li Jing Li Ya‐Wei Fan Ze‐Yuan Deng 《International Journal of Food Science & Technology》2014,49(2):453-459
Medium‐ and long‐chain triacylglycerols (MLCTs)–enriched structured lipid (SL) was synthesised through enzymatic interesterification from Cinnamomum camphora seed oil (CCSO) and camellia oil (CO) using Lipozyme RM IM from Rhizomucor miehei as a biocatalyst. Effects of different reaction conditions including substrate molar ratio, reaction time and reaction temperature were investigated. Results showed that 55.81% of total MLCT species (CCO/LaCL, LaCO/LCL, COO/OCO and LaOO/OLaO) was obtained in the interesterified product under the optimal conditions of substrate molar ratio of 1:1.5 (CCSO/CO) at 60 °C for 3 h. Thereafter, fatty acid profiles, tocopherol contents and physiochemical characteristics of the interesterified product and physical blend were comparatively investigated. The fatty acid composition of the interesterified product consisted of capric acid (26.33%), lauric acid (21.29%) and oleic acid (42.33%). It should be mentioned that the interesterified product contained predominantly oleic acid (88.69%) at Sn‐2 position, while MCFAs (68.05%) at Sn‐1,3 positions. Compared with physical blend, the reduction in tocopherol contents and changes of physiochemical characteristics occurred in SL. The smoke point of the interesterified product was much higher than that of the physical blend, which meant that such MLCTs‐enriched SL could be better for cooking purpose. 相似文献
105.
Fast pyrolysis of the crushed Delonix regia seed was carried out in a semi-batch reactor at a temperature ranging from 400 to 650°C with an objective to produce bio-oil. The effect of temperature to obtain an optimum condition for maximum bio-oil yield and the composition of pyrolysis product were investigated. The maximum bio-oil yield was found to be 48?wt% at pyrolysis temperature of 600°C. The chemical composition of bio-oil obtained at optimum condition was analysed using Fourier-transformed infrared spectroscopy and Gas chromatography–mass spectrometry. The chemical analysis of the biofuel showed the presence of hydrocarbons in major, aldehydes, ketones, amides, nitriles, etc. The composition and fuel characteristics of the pyrolysis oil obtained in this work show that it may potentially be used as a renewable fuel and chemical feedstock. 相似文献
106.
The objective of this paper is to demonstrate whether air plasma can change the seed germination characteristics, seedling emergence, as well as biochemical reactivity, in Andrographis paniculata (A. paniculata) seedlings by modifying the seed coat and finding a beneficial treatment dose. Eight treatment doses and one control were used to conduct electrical conductivity determination, a germination test, a seedling emergence test and a biochemical assay. The results showed that after being treated with air plasma excited at 5950 V for 10 s, the perme- ability of the seeds was improved significantly, resulting in the acceleration of seed germination and seedling emergence. In the meantime, the catalase activity and catalase isoenzyme expression were also improved, while the malondialdehyde content in the seedlings was decreased (which means greater counteraction with environmental stress). After being treated with 4250 V for 10 s and 5950 V for 20 s, the seed germination was enhanced, but without an obvious change in seedUng emergence. However, after treatment with 3400 V for 20 s and 5100 V for 10 s, the permeability of the seeds was decreased, resulting in a delay in seedling emergence. These results indicate that air plasma can change the physiological and biochemical characteristics of Andrographis paniculata seeds by modifying the seed coat, combined with the effects of the active plasma species, and that different treating doses have different effects. 相似文献
107.
Jian Hong Xiao‐Qin Yang Xianmei Wan Zhifeng Zheng Zoran S Petrović 《Polymer International》2017,66(1):126-132
Rubber seed oil having high free fatty acid content and high unsaturation was used to obtain high quality polyurethane resins through epoxidation and ring opening with methanol and free fatty acids. Two polyols prepared with free fatty acids and without were cured with modified methylene diphenyl diisocyanate to obtain strong, high modulus glassy polyurethanes. The effect of structure on thermal and mechanical properties was analyzed. This showed that the polyol with free fatty acid utilized to obtain a branched structure gave superior crosslinking density and mechanical properties. © 2016 Society of Chemical Industry 相似文献
108.
Aleksandra Maria Staszak Tomasz Andrzej Paw?owski 《International journal of molecular sciences》2014,15(6):10868-10891
The proteome of zygotic embryos of Acer platanoides L. was analyzed via high-resolution 2D-SDS-PAGE and MS/MS in order to: (1) identify significant physiological processes associated with embryo development; and (2) identify changes in the proteome of the embryo associated with the acquisition of seed dormancy. Seventeen spots were identified as associated with morphogenesis at 10 to 13 weeks after flowering (WAF). Thirty-three spots were associated with maturation of the embryo at 14 to 22 WAF. The greatest changes in protein abundance occurred at 22 WAF, when seeds become fully mature. Overall, the stage of morphogenesis was characterized by changes in the abundance of proteins (tubulins and actin) associated with the growth and development of the embryo. Enzymes related to energy supply were especially elevated, most likely due to the energy demand associated with rapid growth and cell division. The stage of maturation is crucial to the establishment of seed dormancy and is associated with a higher abundance of proteins involved in genetic information processing, energy and carbon metabolism and cellular and antioxidant processes. Results indicated that a glycine-rich RNA-binding protein and proteasome proteins may be directly involved in dormancy acquisition control, and future studies are warranted to verify this association. 相似文献
109.
Riparian Salicaceae are prolific producers of short‐lived seeds that require very restrictive hydro‐geomorphic conditions for establishment. It is generally assumed that if floods are able to create nursery sites timed with seed dispersal, recruitment will occur. Other spatial and temporal seed dispersal patterns besides the dispersal period have historically received little attention. However, seed dispersal patterns can be highly variable between regions, species and over the years. In this paper, we report the seed dispersal patterns of three dominant riparian Salicaceae trees in Europe: Populus alba, P. nigra and Salix alba to suggest possible trade‐offs between seed dispersal patterns, germinability, longevity and establishment. Seed rain of the three species was monitored in 33 glue‐coated traps for three months yearly from 2006 to 2008 in an 8‐km stretch of the Middle Ebro River (N Spain), which has a pluvio‐nival regime. P. alba dispersed seeds earlier during a shorter time period and with a fewer number of seed release pulses compared with P. nigra, and especially with S. alba. With overlapping seed dispersal periods, the two latter species occupy similar landform units but rarely compete with P. alba, usually at higher elevations, as shown in a previous study in the same study area. The three species had very high germinability immediately after release (>90%), but longevity in S. alba was eight times shorter than that of its two Populus counterparts. We suggest that S. alba has compensated its lower seed quality with a more spaced seed release in several pulses of similar magnitude. With similar seed dispersal patterns and germinability but a higher longevity, P. nigra had a much higher density of individuals than S. alba in the recruitment zones of the study area. We hope that our results may inform river managers about how to optimize river flows to promote sexual regeneration of these species. Copyright © 2015 John Wiley & Sons, Ltd. 相似文献
110.
Yunwu Zheng Lei Tao Xiaoqing Yang Yuanbo Huang Can Liu Zhifeng Zheng 《International Journal of Hydrogen Energy》2018,43(34):16479-16496
To solve the problem of low aromatic hydrocarbon yield and selectivity in biomass catalytic pyrolysis, we used added oxygen-containing hydrogen supplier of rubber seed oil (RSO) with a higher hydrogen-to-carbon ratio to investigate the thermal decomposition behaviors, kinetic and production distribution of biomass, cellulose and RSO with the weight ratio of 1:2 using thermogravimetric analyzer (TGA) for kinetic analysis and fixed bed reactor with the feed composition of 1.2 g: 0.4 mL/min (Biomass to RSO) for product distribution in non-catalytic and catalytic co-pyrolysis over a HZSM-5 catalyst. The results show that there was a positive synergistic interaction between biomass and RSO according to the difference in weight loss, which could decrease the formation of solid coke at the end of experiment. The addition of the HZSM-5 catalyst can markedly increase the reaction activity, accelerate the reaction rate, and the reaction Ea, leading to a substantial increase in the conversion rate; furthermore, the residual carbon content will decrease, and the activations of Cellulose + RSO + Catalyst and Biomass + RSO + Catalyst are only 50.80 kJ/mol and 62.36 kJ/mol, respectively. The kinetic analysis showed that adding a catalyst did not change the decomposition mechanism. Co-pyrolysis of biomass and RSO could effectively improve the yield and selectivity of aromatics, when the pyrolysis temperature and catalytic temperature were 550 °C and 500 °C, respectively, the mass space velocity of RSO was 0.4 mL/min, the reaction time was 30min, the yields of benzene, toluene, xylene and ethyl benzene (BTXE) were up to 78.77%, and the selectivity of benzene, toluene and xylene was much better. Finally, the coke yield was substantially lower. 相似文献