Research Article New Sample Preparation Method for Quantification of Phenolic Compounds of Tea (Camellia sinensis L. Kuntze): A Polyphenol Rich Plant P. A. Nimal Punyasiri, 1 Brasathe Jeganathan, 2 Jeevan Dananjaya Kottawa-Arachchi, 3 Mahasen A. B. Ranatunga, 3 I. Sarath B. Abeysinghe, 3 M. T. Kumudini Gunasekare, 4 and B. M. Rathnayake Bandara 5 1 Institute of Biochemistry Molecular Biology and Biotechnology, University of Colombo, 00300 Colombo, Sri Lanka 2 Department of Food Science and Technology, Faculty of Agriculture, University of Peradeniya, 20400 Peradeniya, Sri Lanka 3 Tea Research Institute of Sri Lanka, 22100 Talawakelle, Sri Lanka 4 Coordinating Secretariat for Science, Technology & Innovation, 3rd Floor, Standard Charted Building, Janadhipathi Mawatha, 00100 Colombo, Sri Lanka 5 Department of Chemistry, Faculty of Science, University of Peradeniya, 20400 Peradeniya, Sri Lanka Correspondence should be addressed to P. A. Nimal Punyasiri; nimal@ibmbb.cmb.ac.lk Received 5 August 2015; Revised 24 August 2015; Accepted 28 September 2015 Academic Editor: Krystyna Pyrzynska Copyright © 2015 P. A. Nimal Punyasiri et al. his is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. Chemical analysis of the Sri Lankan tea (Camellia sinensis, L.) germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (lavan-3-ols), are readily prone to oxidation in the conventional method of sample preparation. herefore, optimization of the present sample preparation methodology for the proiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures) and freeze-dried leaves (a new procedure), for quantiication of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. he amounts of major metabolites such as catechins, cafeine, gallic acid, and theobromine, recorded in the new sampling procedure via freeze-dried leaves, were signiicantly higher than those recorded in the conventional sample preparation procedure. Additionally new method required less amount of leaf sample for analysis of major metabolites and facilitates storage of samples until analysis. he freeze-dried method would be useful for high throughput analysis of large number of samples in shorter period without chemical deterioration starting from the point of harvest until usage. Hence, this method is more suitable for metabolite proiling of tea as well as other phenol rich plants. 1. Introduction Phenolic compounds are the most commonly studied of all secondary metabolites because of their signiicant con- centration and their signiicant roles in plant tissues [1, 2]. his highly diverse group of secondary metabolites widely is distributed in vegetable foods (legumes, cereals, and fruits) and beverages (tea, cider, and wine), which are important constituents of the human diet [3]. he rapid degradation of lavonoids during the extraction is a major drawback for the accurate quantiication of this ubiquitous group of compounds. Because of their importance as potent antioxidants molecules, quantiication lavonoids in fruits, vegetable, and other crops are important [4]. hey become perishable mainly due to the enzymatic oxidation regulated by the enzyme polyphenol oxidase and light [5, 6]. Polyphenol oxidase is activated when the plant tissues are macerated and the enzymes get mixed with the substrate and the major parts of the native lavonoids are destroyed before quantiication. he sustainability of the tea industry mainly relies on developing new tea (Camellia sinensis, L.) cultivars incorpo- rated with genetic resistance to biotic and abiotic stresses and capable of producing diverse tea products of desired Hindawi Publishing Corporation Journal of Analytical Methods in Chemistry Volume 2015, Article ID 964341, 6 pages http://dx.doi.org/10.1155/2015/964341