The femtosecond time-resolved difference absorption spectra of all-trans-β-Apo-8′-carotenal have been recorded and analyzed by the singular-value decomposition (SVD) method followed by global fitting using a sequent...The femtosecond time-resolved difference absorption spectra of all-trans-β-Apo-8′-carotenal have been recorded and analyzed by the singular-value decomposition (SVD) method followed by global fitting using a sequential model for the excited-state energy relaxation. With this model, we have obtained the excited-state absorption spectra and the lifetimes of the corresponding excited states both in nonpolar solvent n-hexane and polar solvent methanol. Three excited states, namely S3(170fs), S2(2.32ps) and S1(26ps) in n-hexane, and two excited states S2(190fs) and S1(9.4ps) in methanol have been observed. The excited-state absorption spectra of all-trans-β-Apo-8′-carotenal in methanol display a red shift and broadeness, while the lifetime of S1 state becomes shorter. It is proposed that these effects are related to the presence of a carbonyl functional group that leads to the solvent effect on the excited-state energy level. At the same time, it is shown that the SVD method is a useful tool in resolving the time-resolved absorption spectra.展开更多
Maintenance of genome stability by preventing DNA damage is crucially important for counteracting carcinogenesis and age-associated diseases. The levels of niacin, vitamin E, vitamin B12, folate, β-carotene, retinol,...Maintenance of genome stability by preventing DNA damage is crucially important for counteracting carcinogenesis and age-associated diseases. The levels of niacin, vitamin E, vitamin B12, folate, β-carotene, retinol, magnesium, calcium, selenium and zinc, which are key micronutrients considered to be important in the prevention of genome damage, were measured in a range of fresh and processed foods available to consumers in the state of Victoria, Australia. Some of the richest dietary sources of the micronutrients, expressed as a percentage of the (Australian) recommended dietary (daily) intake for adults per 100 g of food, were: wheat germ oil (vitamin E, 1400%);oyster (vitamin B12, 2666%);rice bran (niacin, 296% and magnesium, 212%);chicken liver (folate, 354%);beef liver (retinol, 1777%);golden sweet potato (β-carotene);brazil nuts (selenium, 404%);wheat bran (zinc, 575%);skim milk powder (calcium, 116%). The data will be useful for formulating dietary guidelines for micronutrient intake as well as for formulating functional foods enriched in key micronutrients.展开更多
文摘The femtosecond time-resolved difference absorption spectra of all-trans-β-Apo-8′-carotenal have been recorded and analyzed by the singular-value decomposition (SVD) method followed by global fitting using a sequential model for the excited-state energy relaxation. With this model, we have obtained the excited-state absorption spectra and the lifetimes of the corresponding excited states both in nonpolar solvent n-hexane and polar solvent methanol. Three excited states, namely S3(170fs), S2(2.32ps) and S1(26ps) in n-hexane, and two excited states S2(190fs) and S1(9.4ps) in methanol have been observed. The excited-state absorption spectra of all-trans-β-Apo-8′-carotenal in methanol display a red shift and broadeness, while the lifetime of S1 state becomes shorter. It is proposed that these effects are related to the presence of a carbonyl functional group that leads to the solvent effect on the excited-state energy level. At the same time, it is shown that the SVD method is a useful tool in resolving the time-resolved absorption spectra.
文摘Maintenance of genome stability by preventing DNA damage is crucially important for counteracting carcinogenesis and age-associated diseases. The levels of niacin, vitamin E, vitamin B12, folate, β-carotene, retinol, magnesium, calcium, selenium and zinc, which are key micronutrients considered to be important in the prevention of genome damage, were measured in a range of fresh and processed foods available to consumers in the state of Victoria, Australia. Some of the richest dietary sources of the micronutrients, expressed as a percentage of the (Australian) recommended dietary (daily) intake for adults per 100 g of food, were: wheat germ oil (vitamin E, 1400%);oyster (vitamin B12, 2666%);rice bran (niacin, 296% and magnesium, 212%);chicken liver (folate, 354%);beef liver (retinol, 1777%);golden sweet potato (β-carotene);brazil nuts (selenium, 404%);wheat bran (zinc, 575%);skim milk powder (calcium, 116%). The data will be useful for formulating dietary guidelines for micronutrient intake as well as for formulating functional foods enriched in key micronutrients.
