The bioavailability, potency and distribution of dietary palm Tocopherols and Tocotrienolsin the tissues of red hybrid tilapia, Oreochromis sp.
| dc.contributor.author | Wang Yan | |
| dc.date.accessioned | 2014-11-14T07:54:45Z | |
| dc.date.available | 2014-11-14T07:54:45Z | |
| dc.date.issued | 2005 | |
| dc.description | Master | en_US |
| dc.description.abstract | In Experiment 1, an 8-week feeding trial was carried out to investigate the bioavailability of dietary α-tocopherol (α-T), using eight isonitrogenous and isoenergetic semi-purified diets. The four standard diets (Diets 1 to 4) were supplemented with graded levels of α-tocopheryl acetate (α-ToAc) at 0, 25, 50, and 100 mg/kg diet, respectively. The remaining four test diets (Diets 5 to 8) were supplemented with α-tocopheryl succinate (α-ToSc) at 50 mg/kg, tocotrienols-rich fraction (TRF, extracted from crude palm oil, 500 mg/kg), palm fatty acid distillate (PFAD, 30 g/kg) and crude palm oil (CPO, 100 mg/kg), as dietary vitamin E sources. The verified amounts of α-T in eight experimental diets were 2.98, 28.41, 54.59, 103.39, 46.03, 27.15, 34.20 and 25.65 mg/kg, respectively. All the eight diets were fed to triplicate groups of red hybrid tilapia fingerlings (initial mean weight: 4.14 ± 0.02g) for 8 weeks. A standard linear regression equation of available α-T in diet (y in mg/kg) as a function of liver α-T concentration (χ in μg/g) was derived and used to determine the amount of available α-T in the test diets. It was found that 7.97, 13.83, 24.18, and 14.44 mg/kg, corresponding to 17.31%, 50.95%, 70.72% and 56.30%, respectively, of available α-T in α-ToSc, TRF, PFAD and CPO supplemented diets. When exploring vitamin E distribution, we observed that α-T concentrations in muscle, liver, adipose tissue and skin of tilapia were lower in fish fed diets with α-ToSc compared to the α- ToAc. Tilapia tissues varied in their ability to accumulate tocotrienols with the highest concentrations being found in adipose tissues (47-60% of total vitamin E), followed by liver (27-38%), skin (16-18%) and muscle (about 17%). The concentrations of thiobarbituric acid-reactive substances (TBARS) from Fe2+-catalysed vitamin C induced lipid peroxidation in the muscle and liver tissues of fish fed the TRF diet were the lowest. There were no significant differences in fish percent weight gain, feed conversion ratio and protein efficiency ratio among fish given the various test diets (P>0.05). In Experiment 2, a 9-week feeding trial was conducted to evaluate the effects of dietary vitamin E on fish growth, lipid peroxidation and distribution of tocopherols and tocotrienols in various tissues of red hybrid tilapia. Five semi-purified isonitrogenous and isoenergetic diets were supplemented with 0, 30, 60, 120, and 240 mg/kg, respectively, of total vitamin E derived from TRF. There were no significant differences in fish percent weight gain, feed conversion ratio and protein efficiency ratio among fish given the various test diets (P>0.05). Muscle, liver, plasma, skin, and adipose tissue concentrations of α-tocopherol, α-tocotrienol, and γ-tocotrienol increased linearly in response to increasing dietary concentrations originating from the added TRF. α-Tocopherol constituted 51.2–94.2% of the vitamin E composition of various tissues. The deposition of tocotrienols was highest in the adipose tissue. The concentrations of TBARS in muscle, liver and plasma of tilapia fed diets with no added vitamin E were significantly higher (P<0.05) than those found in the tissues of fish fed diets supplemented with TRF from palm oil. Results obtained from the present study indicated that palm tocotrienols supplementation could markedly enhance the tocotrienols concentration in various tilapia tissues and provide higher protection of these tissues against lipid peroxidation, which ultimately would translate to longer shelf-life for seafood products. | en_US |
| dc.identifier.uri | http://hdl.handle.net/123456789/509 | |
| dc.language.iso | en | en_US |
| dc.subject | Pharmaceutical science | en_US |
| dc.subject | Oreochromis sp. | en_US |
| dc.subject | Red hybrid tilapia | en_US |
| dc.title | The bioavailability, potency and distribution of dietary palm Tocopherols and Tocotrienolsin the tissues of red hybrid tilapia, Oreochromis sp. | en_US |
| dc.type | Thesis | en_US |
Files
License bundle
1 - 1 of 1
Loading...
- Name:
- license.txt
- Size:
- 1.71 KB
- Format:
- Item-specific license agreed upon to submission
- Description: