Law, Pooi San (2012) Nutritional values and antioxidant activities of organically grown vegetables. Universiti Malaysia Sabah. (Unpublished)
|
Text
ae0000001683.pdf Download (3MB) | Preview |
|
|
Text
ae0000001683.pdf Download (3MB) | Preview |
Abstract
The study was conducted to determine the nutrient composition and antioxidant activities of low land vegetables, which are organically grown. Leafy green mustard (Brassica juncea), Chinese kale (Brassica alboglaba), and fruit type vegetable on okra (Abelmoschus esculentus) and long bean (Vigna unguiculata subsp. sesquipedalis) were obtained from selected organic farms registered under Organic Scheme Malaysia. Proximate composition was determined by AOAC method, while total phenolic content were estimated by Folin-Ciocalteu reagent, and the antioxidant activities were measured by l,l-diphenyl-2-picrylhydrazyl CDPPH) radical method, Ferric reducing antioxidant power (FRAP) assay, β- carotene bleaching (BCB) assay, and Oxygen Radical Absorbance Capacity (ORAC). The phenolic compounds responsible for the antioxidant activity were identified by High Performance Liquid Chromatography (HPLC). Results show there was no significant different (p>0.05) in macronutrients content between conventionally and organically grown vegetables. However, the protein content of the conventionally grown vegetables was higher than their organic counterpart, with the highest found in kale (2.24 g/100g FW). The antioxidant activities as determined by 4 assays were found higher in organically grown vegetables, especially in leafy greens with organic mustard has the highest DPPH scavenging activities (25.03%) and ORAC value (29.94 µmol Trolox/g). Organic vegetables were found to have a significantly (p<0.05) higher phenolic compounds that are responsible for the antioxidant activity in particularly quercetin and catechin. The phenolic content was strongly correlated (Rz>0.7) with DPPH and FRAP assay. In conclusion, the basic nutrients of the organically grown vegetables do not seem to be superior to their conventional counterparts. However, the antioxidant activity and the presence of phenolic compounds were found much higher in the organically grown vegetables.
| Item Type: | Academic Exercise |
|---|---|
| Keyword: | low land vegetable, AOAC method, antioxidant activity, phenolic compound, organic |
| Subjects: | T Technology > TX Home economics > TX1-1110 Home economics > TX341-641 Nutrition. Foods and food supply |
| Department: | SCHOOL > School of Food Science and Nutrition |
| Depositing User: | SITI AZIZAH BINTI IDRIS - |
| Date Deposited: | 24 Dec 2013 11:11 |
| Last Modified: | 10 Oct 2017 14:17 |
| URI: | https://eprints.ums.edu.my/id/eprint/7862 |
Actions (login required)
 |
View Item |