Decaffeinated tea extracts and its characterization

Ho, Hon Eong (2010) Decaffeinated tea extracts and its characterization. Universiti Malaysia Sabah. (Unpublished)


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Increasing Interests in separation and purification of natural product constituents have prompted the exploration and advancement of separation technique. Effectiveness of various lignocellulosic adsorbent to obtain raw decaffeinated tea extracts via chromatographic approach was studied. Cheap agricultural lignocellulose materials namely sawdust, sugarcane bagasse, rice husk, loofa, and tea stalk were selected as column packing adsorbent. The total phenolic compounds and the antioxidant activity of the decaffeinated tea extracts were determined by using Folin-Ciocalteu method and 1,1-diphenyl-2-piaylhydrazyl (DPPH) free-radical scavenging antioxidant activity assay respectively. Overall, rice husk adsorbent was the most effective material in decaffeination with lowest caffeine/phenolics ratio of 0.140 compared to 0.829 of the initial tea extract loaded. Total phenolic compounds (expressed In gallic acid equivalent) recovered from the sugarcane bagasse adsorbent were the highest among the adsorbents with 64.45% of recovery, followed by sawdust (49.88%), loota (47.73%), rice husk (45.75%), and tea stalk (38.25%). The antioxidative DPPH free radical-scavenging activity of the initial tea extracts loaded as expressed in ICâ‚…â‚€ was 0.014 mg/mL After column treatment, only decaffeinated tea extracts from sugarcane bagasse and loofa with ICâ‚…â‚€ of 0.005 mg/ml and 0.013 mg/mL respectively were more potent antioxidant than the initial tea extracts. These results suggest that lignocellulose materials provide a useful and cheap option to obtain decaffeinated and purified tea extracts which mainly consist of phenolics compounds.

Item Type: Academic Exercise
Uncontrolled Keywords: purification, separation technique, chromatographic approach, decaffeinated tea extracts, lignocellulose materials, phenolics compounds
Subjects: T Technology > TP Chemical technology
Divisions: SCHOOL > School of Science and Technology
Depositing User: Unnamed user with email
Date Deposited: 07 Sep 2015 05:52
Last Modified: 25 Oct 2017 06:24

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