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Stimulated supercontinuum-radiation generation of carbon disulfide by all-trans-β-carotene fluorescence enhancement effect in liquid core optical fibre 被引量:1
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作者 门志伟 房文汇 +5 位作者 里佐威 曲冠男 高淑琴 陆国会 杨健戈 孙成林 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第8期418-422,共5页
We demonstrate stimulated supercontinuum-radiation of carbon disulfide (CS2) influenced by biological molecules all-trans-stimulated Raman scattering, stimulated Brillouin scattering, all-trans-β-carotene, liquid c... We demonstrate stimulated supercontinuum-radiation of carbon disulfide (CS2) influenced by biological molecules all-trans-stimulated Raman scattering, stimulated Brillouin scattering, all-trans-β-carotene, liquid core optical fibre-carotene in liquid core optical fibre (LCOF). By virtue of the broad fluorescence characteristics and large third-order optical nonlinearities of all-trans-β-carotene, the high-order Stokes lines of stimulated Raman scattering (SRS) and the multi-order Stokes lines of stimulated Brillouin scattering (SBS) excitated by SRS are observed at low input-laser energies. The results indicate that the fluorescence not only enhances the SRS, but also the SBS. These Stokes lines generate the SRS-SBS supercontinuum radiation (RBSR). A flat-amplitude bandwidth of 110 nm from 515 nm to 625 nm is observed when a frequency-doubled Nd:YAG laser at 532 nm with an energy of 0.86 mJ is used. This result is expected to be useful for the multi-wavelength fibre laser. 展开更多
关键词 stimulated Raman scattering stimulated Brillouin scattering all-trans-β-carotene liquid core optical fibre
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Difference in effect of temperature on absorption and Raman spectra between all-trans-β-carotene and all-trans-retinol
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作者 曲冠男 李硕 +8 位作者 孙成林 刘天元 吴咏玲 孙尚 单肖宁 门志伟 陈伟 里佐威 高淑琴 《Chinese Physics B》 SCIE EI CAS CSCD 2012年第12期457-462,共6页
Temperature dependencies (81 ℃- 18 ℃) of visible absorption and Raman spectra of all-trans-β-carotene and all-trans-retinol extremely diluted in dimethyl sulfoxide are investigated in order to clarify temperature... Temperature dependencies (81 ℃- 18 ℃) of visible absorption and Raman spectra of all-trans-β-carotene and all-trans-retinol extremely diluted in dimethyl sulfoxide are investigated in order to clarify temperature effects on different polyenes. Their absorption spectra are identified to be redshifted with temperature decreasing. Moreover, all-trans-β-carotene is more sensitive to temperature due to the presence of a longer length of conjugated system. The characteristic energy responsible for the conformational changes in all-trans-β-carotene is smaller than that in all-transretinol. Both of the Raman scattering cross sections increase with temperature decreasing. The results are explained with electron-phonon coupling theory and coherent weakly damped electron-lattice vibrations model. 展开更多
关键词 all-trans-β-carotene all-trans-RETINOL REDSHIFT Raman scattering cross section
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Study of second-order nonlinear hyperpolarisability of all-trans-β-carotene in solutions by linear spectroscopic technique
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作者 房文汇 门志伟 +5 位作者 孙成林 曲冠男 杨光 里佐威 高淑琴 陆国会 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第6期362-366,共5页
This paper demonstrates the second-order nonlinear hyperpolarisability γ of all-trans-β-carotene in different solvents by linear spectroscopic technique that is based on resonance Raman scattering and UV-VIS (Ultra... This paper demonstrates the second-order nonlinear hyperpolarisability γ of all-trans-β-carotene in different solvents by linear spectroscopic technique that is based on resonance Raman scattering and UV-VIS (Ultraviolet-visible) absorption spectroscopy. Owing to the two-level model well describing the link that exists between the resonance Raman scattering and stimulated Raman scattering, the stimulated Raman polarisability αR can be calculated through the two-photon resonance system. The value of γ of all-trans-β-carotene in carbon bisulfide solution is 6.435×10^-33 esu (1 esu of resistance = 8.98755×10^11Ω) that is close to the true value, because the solution of all-trans-β-carotene in carbon bisulfide satisfies the rigid resonance Raman scattering condition. This method is expected to be worthy of applications to measure the second-order nonlinear hyperpolaxisability of a conjugate organic molecule. 展开更多
关键词 all-trans-β-carotene second-order nonlinear hyperpolarisability rigid resonance Raman scattering UV-VIS absorption spectroscopy
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Selection of Parents for Breeding Edible Varieties of Sweetpotato with High Carotene Content 被引量:28
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作者 MA Dai-fu LI Qiang LI Xiu-ying LI Hong-min TANG Zhong-hou HU Ling CAO Qing-he XIE Yi-ping WANGXin 《Agricultural Sciences in China》 CAS CSCD 2009年第10期1166-1173,共8页
Sweetpotato varieties with high carotene content have high value for human health. This work aims to improve the breeding efficiency of special varieties with high carotene content by combining molecular markers and a... Sweetpotato varieties with high carotene content have high value for human health. This work aims to improve the breeding efficiency of special varieties with high carotene content by combining molecular markers and agronomic traits to evaluate and screen the parents. The cluster analysis was carried out to identify and screen promising parents by utilizing phenotypic results of the agronomic and characteristic traits, and RAPD and ISSR markers of 15 parents and their offspring by group crossing. Among different parental materials, greater variations were observed in two important traits, the carotene content and the storage root yield. Negative correlation was found between the carotene content and both fresh and dried root yields. The most significant positive correlation was between the carotene content of parents and that of their offspring, with the coefficient of correlation value of 0.7932**. The relationship based on the agronomic characters of the trial materials was not in agreement with the known genealogy, while that based on the molecular marker data showed better result. Each primer amplified 13.8 bands oflSSR markers on average, in which the rate of polymorphic loci was 89.6%. 9.4 bands of RAPD markers were arnplified per primer, in which the rate of polymorphic bands was 74.46%. Large genetic variation of carotene content was found among the parents. For analyzing the genetic diversity of sweetpotato, the molecular marker methods were better than morphological traits; ISSR markers were more efficient than RAPD markers. The combination of molecular markers and agronomic trait analysis may provide valuable theoretic basis for selection of parents to breed new varieties with high carotene content. 展开更多
关键词 SWEETPOTATO carotene selection of parents RAPD ISSR cluster analysis
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Mutation Breeding of β-carotene Producing Strain B. trispora by Low Energy Ion Implantation 被引量:2
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作者 张宁 虞龙 《Plasma Science and Technology》 SCIE EI CAS CSCD 2009年第1期110-115,共6页
Ion beam bioengineering technology as a new mutation approach has been widely used in the biological breeding field. In this paper the application of low energy nitrogen ion implantation in the β-carotene producing s... Ion beam bioengineering technology as a new mutation approach has been widely used in the biological breeding field. In this paper the application of low energy nitrogen ion implantation in the β-carotene producing strain, Blakeslea trispora(-) was investigated. The effects of different fermentation conditions on β-carotene production by a high yield strain were examined. Results showed that two β-carotene high yielding strains B.trispora(-) BH3-701 and BH3-728 were screened out and the averaged production of β-carotene was raised by 178.7% and 164.6% respectively after five passages in the shaking flasks. Compared with the original strain, the highest yield strain BH3-701 was potent in accumulating β-carotene, especially in the later stage, and greatly increased production efficiency. 展开更多
关键词 blakeslea trispora β-carotene ion beam implantation mutation screen
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Biochemical changes in phenols,flavonoids,tannins,vitamin E,β-carotene and antioxidant activity during soaking of three white sorghum varieties 被引量:7
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作者 Abd El-Moneim MR Afify Hossam S El-Beltagi +1 位作者 Samiha M Abd El-Salam Azza A Omran 《Asian Pacific Journal of Tropical Biomedicine》 SCIE CAS 2012年第3期203-209,共7页
Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilav... Objective:To investigate the changes in total phenols,flavonoids,tannins,vitamin E, β-carotene and antioxidant activity during soaking of three white sorghum varieties.Methods: The changes in total phenols,total ilavonoids,tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity during soaking of sorghum grains were determined.Results:Total phenols,total flavonoids,tannins,vitamin E,P-carotene and antioxidant activity in raw sorghum were ranged from 109.21 to 116.70,45.91 to 54.69,1.39 to 21.79 mg/100 g,1.74 to 5.25,0.54 to 1.19 mg/kg and 21.72%to 27.69%and 25.29%to 31.97%,respectively. The above measured compounds were significantly decreased after soaking.p-Hydroxybenzoic acid,vanillic acid,syringic acid and cinnamic acid represent the major phenolic acids in Dorado variety.While ferulic acid,p-coumaric acid,gallic acid and caffeic acid represent the major phenolic acids in Shandaweel-6.On the other hand,protocatechuic acid represents the major phenolic acids in Giza-15.Regarding flavonoids components,Dorado was the highest variety in kampferol and naringenin while Shandaweel-6 was the highest variety in luteolin, apigenin,hypersoid,quercelin and christen.Finally,Giza-15 was the highest variety in catechin. Phenolic acids,flavonoid compounds and antioxidant activities were decreased after soaking. Conclusions:Sorghum varieties have moderate quantities from total phenols,total flavonoids, tannins,phenolic acids compounds,flavonoid components,vitamin E,P-carotene and antioxidant activity which decreased after soaking. 展开更多
关键词 SORGHUM SOAKING Total PHENOLS FLAVONOIDS TANNINS Vitamin E Β-carotene Antioxidant activity Phenolic acids Flavonoid components Biochemical change
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Combining Ability and Parent-Offspring Correlation of Maize(Zea may L.) Grain β-Carotene Content with a Complete Diallel 被引量:1
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作者 LI Run XIAO Lan-hai +7 位作者 WANG Jing LUYan-li RONG Ting-zhao PAN Guang-tang WU Yuan-qi TANG Qilin LAN Hai CAO Mo-ju 《Journal of Integrative Agriculture》 SCIE CAS CSCD 2013年第1期19-26,共8页
Vitamin A deficiency has become a worldwide problem.Biofortified foods can potentially be an inexpensive,locally adaptable,and long-term solution to dietary-nutrient deficiency.In order to improve the β-carotene cont... Vitamin A deficiency has become a worldwide problem.Biofortified foods can potentially be an inexpensive,locally adaptable,and long-term solution to dietary-nutrient deficiency.In order to improve the β-carotene content in maize grain by breeding and minimize vitamin A deficiency,a complete diallel cross was designed with eight inbred lines of maize,and 64 combinations were obtained in this study.The experimental combinations were planted in Yunnan and Sichuan provinces,respectively,with a random complete block design.The β-carotene contents in the grains of the experimental materials were analyzed by high-performance liquid chromatography.Among the tested materials,the effect difference of general combining ability of the β-carotene content was significant;however,the effect difference of the special combining ability and the reciprocal effect were not significant.The β-carotene content of maize grain was not influenced significantly by the cross and the reciprocal cross.There was a significant correlation about the β-carotene content in the maize grains between the F 1 and their parents.The combinations with high β-carotene content were obviously influenced by the environment,and the mean value of β-carotene content for the experimental materials planted in Ya'an of Sichuan was higher than that planted in Yuanjiang of Yunnan,with the results being significant at the 0.01 level. 展开更多
关键词 MAIZE β-carotene content complete diallel cross combining ability
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Kinetics of Extraction of <i>β</i>-Carotene from Tray Dried Carrots by Using Supercritical Fluid Extraction Technique 被引量:1
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作者 Kamalpreet Kaur Uma Shanker Shivhare +1 位作者 Santanu Basu G. S. Vijaya Raghavan 《Food and Nutrition Sciences》 2012年第5期591-595,共5页
β-carotene acts as an antioxidant and is receiving growing interest due to its ability as protecting agent against heart diseases, cancer and strengthening effect on red blood cells. The main aim of this work was to ... β-carotene acts as an antioxidant and is receiving growing interest due to its ability as protecting agent against heart diseases, cancer and strengthening effect on red blood cells. The main aim of this work was to study the kinetics of the supercritical fluid extraction of β-carotene from tray dried carrots at 40℃, 50℃ and 55℃ and 30, 35 and 40 MPa at SC-CO2 flow rate of 2.0 L/min for extraction time of up to 6 h. It was observed that the concentration of β-carotene in the extract increased with pressure, temperature and extraction time. The results indicated that yield was found to be maximum at 45℃ and 35 MPa at 2 L/min SC-CO2 flow rate. Concentration of β-carotene in the extract increased with SC-CO2 flow rate. Weibull distribution model described adequately the kinetics of extraction of β-carotene from carrots. 展开更多
关键词 β-carotene KINETICS Supercritical Fluid EXTRACTION CARROTS Weibull Distribution Model
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Genotype x Environment Interaction of Carotene Content of Yellow-Fleshed Cassava Genotypes in Nigeria
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作者 Norbert G. Maroya Peter Kulakow +2 位作者 Alfred G.O. Dixon Busie Maziya-Dixon Moshood A. Bakare 《Journal of Life Sciences》 2012年第6期595-601,共7页
Cassava is an important starchy root crop and a major staple for more than 70 million people in Nigeria. New yellow-fleshed genotypes are being developed to combat vitamin A deficiency. Trials of 18 yellow-fleshed gen... Cassava is an important starchy root crop and a major staple for more than 70 million people in Nigeria. New yellow-fleshed genotypes are being developed to combat vitamin A deficiency. Trials of 18 yellow-fleshed genotypes and two officially released white-fleshed clones, used as checks for 2008/2009 and 2009/2010 seasons in five major cassava growing agroecological zones of Nigeria. The trial locations were Ikenne (humid forest), Ibadan (forest-savanna transition), Ubiaja (subhumid forest), Mokwa (southern Guinea savanna) and Zaria (northern Guinea savanna). At each location, the trial was established in a randomized complete block design with four replications. The objective of the study was to assess genotype performance and genotype ~ environment interaction for total carotene concentration (TCC), total carotene content per root (TC-R), and total carotene content per plant (TC-P). Significant differences (P 〈 0.001) among genotypes, environments and genotype x environment interaction for all the traits evaluated were observed. For TCC, TC-R and TC-P, the best genotypes across the 10 environments were TMS I051601, TMS 1050311, and TMS 1050998. Variation among genotypes accounted for most of the Total Sum of Squares for TCC (67.9%), TC-R (39.0%) and TC-P (35.9%). These characteristics of total carotene were also highly correlated. This study revealed that cassava with total carotene concentration can be assessed using either the TCC, or the TC-R, or the TC-P. 展开更多
关键词 Yellow-fleshed cassava carotene genotype x environment interaction.
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Consumption Pattern of Carotene Rich Foods and Development of a Year Calendar
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作者 DEVADAS RAJAMMAL,P. CHANDRASEKHAR,U. +2 位作者 PREMAKUMARI S. AND SAISHREE, R.(Avinashilingam Institute for Home Science and Higher Education for Women, Deemed University, Coimbatore 641 043, India) 《Biomedical and Environmental Sciences》 SCIE CAS CSCD 1996年第2期212-222,共11页
Consumption pattern of beta carotene rich foods from 500 households of Coimbatore district was elicited. Through market surveys in four seasons namely: summer, south-west monsoon, north-east monsoon and winter, a year... Consumption pattern of beta carotene rich foods from 500 households of Coimbatore district was elicited. Through market surveys in four seasons namely: summer, south-west monsoon, north-east monsoon and winter, a year calendar of beta carotene rich foods was developed. The total and beta carotene contents of five commonly consumed beta carotene rich foods both in raw and cooked states were determined. Results indicated that greens were mainly purchased from market and consumed 2-3 times per week. Cooking loss was maximum in boiling and minimum in shallow fat frying. Curry leaves (Murraya koenigii),amaranth tender (Amaranthus gangeticus), agathi (Sesbania grandopra), and ponnanganni (Alternanthera sessilis) were the carotene rich foods available round the year. Cost of most greens was highest in summer and lowest in north-east monsoon. Within a cost of 13-14 ps in summer, 4-10 ps in south-west monsoon and north-west monsoon and 4-12 ps in winter season, the entire day's requirement of beta carotene (2400μg) could be obtained in the form of agathi/amaranth throughout the year: in the form of drumstick leaves and mint in south-west monsoon; as curry leaves and coriander leaves in winter and as agathi,paruppukeerai and amaranth in summer. From this year calendar, according to seasonal availability and cost, low-cost high carotene foods can be selected and used for increasing the beta carotene intake in the intervention programmes and in the community 展开更多
关键词 RICH Consumption Pattern of carotene Rich Foods and Development of a Year Calendar
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AN INVESTIGATION ON THE INTERACTION MECHANISM OF β-CAROTENE WITH HALOGEN ATOM PRODUCED IN HALOBENZENE BY UV IRRADIATION
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作者 Yong LI Bing SHI Qing Gui SHA Department of Chemistry,Tsinghua University,Beijing,100084 《Chinese Chemical Letters》 SCIE CAS CSCD 1990年第3期197-200,共4页
ESR measurements using spin trapping technique were carried out for β-carotene-halobenzene system under UV light irradiation.The ESR spectra observed in the presence and in the absence of β-carotene are markedly dif... ESR measurements using spin trapping technique were carried out for β-carotene-halobenzene system under UV light irradiation.The ESR spectra observed in the presence and in the absence of β-carotene are markedly different.The possible scheme of β-carotene interacting with halogen atom was proposed. 展开更多
关键词 ESR AN INVESTIGATION ON THE INTERACTION MECHANISM OF carotene WITH HALOGEN ATOM PRODUCED IN HALOBENZENE BY UV IRRADIATION UV
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Solvent effects on the S_0→S_2 absorption spectra of β-carotene
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作者 刘伟龙 王德敏 +2 位作者 郑植仁 李艾华 苏文辉 《Chinese Physics B》 SCIE EI CAS CSCD 2010年第1期262-267,共6页
Absorption spectra of β-carotene in 31 solvents are measured in ambient conditions. Solvent effects on the 0-0 band energy, the bandwidth, and the transition moment of the S0 → S2 transition are analysed. The discre... Absorption spectra of β-carotene in 31 solvents are measured in ambient conditions. Solvent effects on the 0-0 band energy, the bandwidth, and the transition moment of the S0 → S2 transition are analysed. The discrepancies between published results of the solvent effects on the 0-0 band energy are explained by taking into account microscopic solutesolvent interactions. The contributions of polarity and polarizability of solvents to 0-0 band energy and bandwidth are quantitatively distinguished. The 0- 0 transition energy of the S2 state at the gas phase is predicted to locate between 23000 and 23600 cm^-1. 展开更多
关键词 solvent effects absorption spectra Β-carotene
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RESEARCH ON SERUM LEVELS OF RETINOL,α-TOCOPHEROL β-CAROTENE,AND 12 ELEMENTS IN GASTRIC DYSPLASIA AND GASTRIC CANCER PATIENTS
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作者 程五凤 史奎雄 +4 位作者 潘金妹 许秀娴 刘海卫 袁耀宗 杨中枢 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 1994年第3期216-221,共6页
Serum levers of retinol, α-tocopherol, β-carotene and elements(Zn, Cu, Mn, Ca, Mg, Cr, Co, Cd, Mo, Se)were detemined in 45 gastric cancer and 41 gastric dysplasia patients, and 48 normal subjects. The results showe... Serum levers of retinol, α-tocopherol, β-carotene and elements(Zn, Cu, Mn, Ca, Mg, Cr, Co, Cd, Mo, Se)were detemined in 45 gastric cancer and 41 gastric dysplasia patients, and 48 normal subjects. The results showed that βcarotene and Se, Co were lower in gastric cancer patients than that in gastric dysplasia patients or in normal subjects ,Ni and Cr levels were lower and Mn , Ca and Cd were higherin gastric cancer than in dysplasia patients. Zn , Fe , Cr . Cdwere lower and Mn, Ca, Mg. Mo levels were higher in gastric cancer patients than in normal. The differences mentioned are statistically significant. The stepwise discriminant analysis of 10 variables( Mn, Fe, Ca, Cr,Mo, Co, Cd, Se, α-tocophrol, β-carotene) were used in identifying gastric cancer . with 100% of the positive rate.The potential protective effect of β-carotene and Se against gastric cancer is an interesting postulate. We suggest that optimum supplement of β- carotene and Se might will be beneficial to gastric dysplasia patients in preventing the development of gastric cancer. 展开更多
关键词 Gastric cancer Gastric dysplasia β-carotene Selenium.
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Retention of <i>β</i>-Carotene in Cream-Fleshed Sweetpotato-Based Complementary Food Stored in Different Containers under Simulated Tropical Temperature and Humidity
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作者 Francis Kweku Amagloh Louise Brough +3 位作者 Janet L. Weber Anthony N. Mutukumira Allan Hardacre Jane Coad 《Food and Nutrition Sciences》 2013年第9期23-28,共6页
The stability of β-carotene in cream-fleshed sweetpotato-based complementary food stored in three different containers under simulated tropical temperature of 32°C and 85% relative humidity in an environmental c... The stability of β-carotene in cream-fleshed sweetpotato-based complementary food stored in three different containers under simulated tropical temperature of 32°C and 85% relative humidity in an environmental chamber for 24 weeks was investigated. The formulation stored in a metallised polyester film in a refrigerator (approximately 3.0°C and 95% relative humidity) retained about 81% of β-carotene at 24 weeks, with no significant change in the moisture content. The formulation stored in either a metallised polyester film or a translucent polypropylene container placed in the environmental chamber retained approximately half of the β-carotene at 24 weeks, with a slight increase in moisture content. However, the formulation held in a transparent low-density polyethylene bag had the lowest β-carotene retention (37%) and the highest moisture content at week 24. Within the limits of this study, it has been demonstrated that β-carotene in cream-fleshed sweetpotato-based complementary food was well retained when moisture uptake was minimised. 展开更多
关键词 Β-carotene Complementary Food Storage SWEETPOTATO
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Bioavailability of Beta Carotene in Traditional Fermented, Roasted Granules,<i>Gari</i>from Bio-Fortified Cassava Roots
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作者 Olapeju O. Phorbee Ibiyemi O. Olayiwola Silifat A. Sanni 《Food and Nutrition Sciences》 2013年第12期1247-1254,共8页
Vitamin A Deficiency (VAD) is a major public health issue and of global concern, as it affects millions of preschool children and pregnant women worldwide. Bio-fortification has emerged as a technology with potential ... Vitamin A Deficiency (VAD) is a major public health issue and of global concern, as it affects millions of preschool children and pregnant women worldwide. Bio-fortification has emerged as a technology with potential to sustainably alleviate VAD especially in the sub-Saharan Africa, using staples like cassava. This work studied bioavailability of beta carotene (BC) in two processed gari samples from bio-fortified cassava varieties: 01/1412 and 01/1371, using 40 weanling albino rats, grouped into four, acclimatized for 1 week and fed experimentally for 4 weeks. Plasma beta carotene (PBC) was determined with HPLC while bioavailable BC calculated using conventional linear dose response plot. The mean rat weight gain was 5.3 g with significant difference (p< 0.001) among them while mean PBC was 60.5 and 61.2 μg/dL for 01/1412 and 01/1371 respectively. From this study, a large variation of PBC among animals was found with a weak linear relationship between feed and PBC, showing that BC bioavailability is not limited to intake. The BC bioavailability of the samples was between 11% and 18% with sample from variety 01/1371 recording higher percentage (18%). Gari from bio-fortified cassava roots processed traditionally, had appreciable bioavailable BC, which can contribute to the fight against VAD and improve nutritional status in developing countries although the magnitude of the problem requires a combination of strategies, of which bio-fortification is just one. However, further work is necessary on public awareness and adoption of the product. 展开更多
关键词 Bioavailability Bio-Fortification Beta-carotene CASSAVA Gari
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Light and Electron Microscopic Study of the Effect of Orlistat on the Liver of Adult Male Albino Rats and the Possible Protective Role of <i>β</i>-Carotene
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作者 Sahar Youssef 《Forensic Medicine and Anatomy Research》 2018年第2期20-36,共17页
Orlistat is a safe and effective drug to treat obesity by acting as a pancreatic and gastric lipase inhibitor, resulting in reduction in fat absorption. There is also concern that it may be linked with an increased th... Orlistat is a safe and effective drug to treat obesity by acting as a pancreatic and gastric lipase inhibitor, resulting in reduction in fat absorption. There is also concern that it may be linked with an increased threat of serious hepatic incidents. The present work was carried out to study the effect of orlistat on the histological, immunohistochemical and electron microscopic structure of the liver in the adult male albino rats and the possible protective role of β-carotene administration. Forty adult albino rats were subjected to experiment for two weeks as follows: group 1 (control), group II, each animal received 0.52 mg/kg bw/day β-Carotene, group III, each animal received orlistat 32 mg/kg/day, and group IV received β-Carotene, 1hour before the administration of orlistat at same dose of group II & III. The liver from each animal was dissected out and processed for histological, (light and electron microscopic study). The result of Hep-Par1 for immunohistochemistry was statistically analyzed. The results showed that orlistat treated group displayed variable disturbance of liver architecture, from dilatation, congested central and portal veins, branching of bile ductules, mononuclear cellular infiltration, areas of hemorrhages, cytoplasmic vacuolation and pyknotic nuclei. The most obvious changes were that degenerative changes in hepatocytes led to depletion of glycogen content of hepatocytes. Hep Par-1 revealed a wide area of negative immune expression around the central vein and in some hepatocytes. Other hepatocytes expressed weak reaction. Ultrastructure examination displayed hepatocytes with swollen mitochondria and others with an electron-dense matrix. The combined treatment of β-Carotene and orlistat led to a marked improvement in most of the previously mentioned changes. It was concluded that orlistat-induced hepatic toxicity. Thus, clinicians should cautiously monitor their patients for signs of hepatic dysfunction. Using an antioxidant such as β-Carotene decreased the toxicity of orlistat. 展开更多
关键词 LIVER ORLISTAT Ultrastructure Β-carotene
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EFFECT OF NITRATE AND PHOSPHATE ON ACCUMULATION OF β-CAROTENE ISOMERS IN DUNALIELLA SALINA
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作者 刘建国 吴超元 +2 位作者 陈念洪 王玉君 俞立东 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1996年第2期165-169,共5页
DunaIiella salina, a halotolerent unicellular green alga, can accurmulate a Iarge amount of β-caroteneunder environmental conditions. The isorners of β-carotene extIacted from D. salina culturedin medium with differ... DunaIiella salina, a halotolerent unicellular green alga, can accurmulate a Iarge amount of β-caroteneunder environmental conditions. The isorners of β-carotene extIacted from D. salina culturedin medium with different nitrate and phosphate concentrations were analysed by HPLC with Alox-Talumins column. At least six isomers were found in different proportions depending on the culture me-dia’s nitrate and/or phosphate concentrations. Nitrate and/or phosphae defidency was conducive tothe accumulation of totaI cis isomers but not of al1 trans isomer. lt is sUggeSted that 1 mmol/L KNO<sub>3</sub>and 0.1 mmol/L KH<sub>2</sub>, PO<sub>4</sub> are favourable for accumulation of total cis β-carotene. 展开更多
关键词 DUNALIELLA salina Β-carotene isomer cis and trans ISOMERS accumulation NITRATE and PHOSPHATE EFFECT
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Applicability of in Vitro Models in Predicting the in Vivo Bioavailability of Lycopene and β-Carotene from Differently Processed Soups
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作者 Marie Alminger Cecilia Svelander +4 位作者 Anna Wellner Rebeca Martinez-Tomas Lucy Bialek Elvira Larque Francisca Perez-Llamas 《Food and Nutrition Sciences》 2012年第4期477-489,共13页
Presently, there is no clear consensus on the best approach to estimate carotenoid bioavailability. The best alternative would be to use human studies, but they are labour-intensive and expensive and can only be used ... Presently, there is no clear consensus on the best approach to estimate carotenoid bioavailability. The best alternative would be to use human studies, but they are labour-intensive and expensive and can only be used to investigate a limited number of samples. Hence, a number of in vitro: models have been developed to study pre-absorptive processes and factors affecting bioavailability. The question is, however, how well the results obtained by the various methods correlate to each other and to the in vivo situation. In the present paper, we have compared in vivo data from two human studies on differently processed soups containing carrots, tomato and broccoli, with results obtained by in vitro characterisation of the same soups. In vitro bioaccessibility was estimated by a static in vitro digestion investigating matrix release and micellarization of carotenoids and by uptake studies in a human intestinal cell line (Caco-2). In vivo data was obtained from clinical studies measuring total plasma carotenoid concentrations in human subjects after 4 weeks daily consumption of the soups. Comparison of the in vitro and in vivo results indicate that the combination of a two-step in vitro digestion and Caco-2 cells seems to be a useful tool for estimation of β-carotene bioaccessibility and screening of factors governing the release of β-carotene from this type of food. For lycopene the in vitro and in vivo results were less consistent, suggesting that reliable prediction of lycopene bioavailability might be more problematic. 展开更多
关键词 In Vitro Digestion Human UPTAKE Caco-2 Cells Β-carotene LYCOPENE carotene Bioavailability
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EFFECTS OF Mg^(2+), NaCl, CITRIC ACID, AND OTHER FACTORS ON SYNTHESIS AND ACCUMULATION OF β-CAROTENE IN DUNALIELLA SALINA
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作者 金海洙 郭承华 +3 位作者 贺君 王青华 姜竹茂 孙福章 《Chinese Journal of Oceanology and Limnology》 SCIE CAS CSCD 1998年第4期364-368,共5页
The effect of Mg2+, NaCl and citric acid on the accumulation of β-carotne inDunaliella Salina was studied. The experimental results showed that 10. 5 mmol/L Mg2+, 5 mol/LNaCI, 3 μmol/L, citric acid, and CO2 are favo... The effect of Mg2+, NaCl and citric acid on the accumulation of β-carotne inDunaliella Salina was studied. The experimental results showed that 10. 5 mmol/L Mg2+, 5 mol/LNaCI, 3 μmol/L, citric acid, and CO2 are favordse for Dunaliella Salina cell growth and β-carotene accu-mulation. After 144 h culture under the above conditions, the Dunaliella Salina biomass increased by7. 18 times; β-carotene reached 9. 61 %. 展开更多
关键词 DUNALIELLA SALINA Β-carotene ACCUMULATION
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鱼鳞明胶-脂肪酸偶联物荷载β-胡萝卜素制备饮料的储藏及模拟消化稳定性
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作者 龙道崎 董楠 +1 位作者 田桂林 李昊昕 《食品研究与开发》 CAS 2024年第15期9-17,79,共10页
为提升β-胡萝卜素的稳定性和生物活性,以8~18烷基链长的明胶-脂肪酸偶联物(gelatin-fatty acid conjugate,GFC)为载体,用于荷载β-胡萝卜素以制备饮料,同时探讨外部条件对GFC荷载β-胡萝卜素效率的影响,并对荷载有β-胡萝卜素的GFC(β-... 为提升β-胡萝卜素的稳定性和生物活性,以8~18烷基链长的明胶-脂肪酸偶联物(gelatin-fatty acid conjugate,GFC)为载体,用于荷载β-胡萝卜素以制备饮料,同时探讨外部条件对GFC荷载β-胡萝卜素效率的影响,并对荷载有β-胡萝卜素的GFC(β-GFC)在饮料加工后的储藏稳定性及模拟胃肠消化进行评价。运用明胶-辛酸结合物(gelatin-caprylic acid conjugate,GCC)、明胶-月桂酸结合物(gelatin-lauric acid conjugate,GLC)和明胶-油酸结合物(gelatin-oleic acid conjugate,GOC)荷载β-胡萝卜素制备饮料(β-GCC、β-GLC和β-GOC),发现搅拌速率为600 r/min、温度为40℃、GCC浓度为2 mg/mL时,GCC溶液中的β-胡萝卜素浓度达到最高(7.31±0.14)μg/mL;当搅拌速率为400 r/min、温度为40℃、GLC浓度为3 mg/mL时,GLC溶液中的β-胡萝卜素浓度达到最高(10.76±0.30)μg/mL;在搅拌速率为500 r/min、温度为30℃、GOC浓度为3 mg/mL时,GOC溶液中β-胡萝卜素浓度达到峰值(13.21±0.34)μg/mL。利用GFC荷载β-胡萝卜素加工饮料并探究其在热加工及储藏条件下的稳定性,发现β-GOC饮料在70、80、90℃下连续加热50 min后,β-胡萝卜素降解速率最慢,并在储藏第36天时,β-胡萝卜素保留率最高(在25℃下保留率为77.02%,在4℃下保留率为83.87%)。在模拟体外消化中发现,GFC蛋白质的保留率顺序为GOC>GCC>GLC,β-胡萝卜素的保留率顺序为GOC>GLC>GCC。综上所述,GFC对疏水性营养物质在加工、储藏及胃肠道过程中具有较强的保护效果。 展开更多
关键词 明胶 脂肪酸 Β-胡萝卜素 饮料 稳定性
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