DBPapers
DOI:10.5593/SGEM2013/BF6/S25.015

INTRASPECIFIC VARIABILITY OF ORIGANUM CROP VARIETIES DEPENDING ON GROWING CONDITIONS: SECONDARY METABOLITES ACCUMULATION

O. Cioanca, C. Mircea, C. Iancu, E. Gille, M. Hăncianu
Tuesday 6 August 2013 by Libadmin2013

References: 13th SGEM GeoConference on Nano, Bio And Green – Technologies For A Sustainable Future, www.sgem.org, SGEM2013 Conference Proceedings, ISBN 978-619-7105-06-3 / ISSN 1314-2704, June 16-22, 2013, 177 - 184 pp

ABSTRACT

Oregano is one of the Origanum species widespread in Romania, while also having the highest variability in the genre to which it belongs. Although it is used in food, the plants of Romanian provenience are poorly studied in terms of phenolic chemical composition. Flavonoids and polyphenolic acids represent one of the most important groups with antioxidant, antimicrobial and even anti-inflammatory potential. Polyphenols are of particular importance in human health being involved in the inhibition of oxidative processes. Thus, in our research we aimed to analyse this fraction and to study the variability of Origanum vulgare L. populations with red flowers harvested from biological cultures in Neamt County. Seedlings were planted in the experimental field in the spring of 2008, harvesting of the vegetal material taking place after the third year of growth in 2010. For Neamt County 2009/2010 agricultural year was characterized as being a rainy year, the annual average deviations ranging from -18.9 mm (April) to 70.6 mm (June). In July 2010 we harvested nine samples of plant material grown under the same conditions but different in terms of cultivation (distance between rows 25 cm and 15cm (unwedded), 25, 50 cm distance between plants in the same row). In fact, the samples represent three randomized cultural variation repetitions (R1,R2,R2) imposed by the statute of organic culture. These repetitions ensure the plant reproducibility and productivity. The screening of methanolic extracts obtained from the aerial parts of the nine samples of O. vulgare red flower samples (O1-O9) focused on identifying the components. Using TLC, spectrophotometry and HPLC, we determined the content of total polyphenols, flavonoids, polyphenol acids and hydroxycinnamic acids, knowing that rosmarinic acid is representative for Lamiaceae family. Both flavonoid and phenolic content of the nine samples varied greatly, even for all 3 repetitions of the same variation remarking O4 sample the second version of culture (25 cm) first rehearsal (V2R1), that contains the maximum amount (0.7374 g%). Regarding rosmarinic acid concentration it is however noted that the variation between samples is rather low, the value ranging from 1.94 and 3.76 g%. In general, the samples with a high concentration of flavones also have a high concentration of polyphenolic/ hydroxycinnamic acids. Moreover, the phytochemical study results prove that there is an individual biochemical variability phenotype in the accumulation of polyphenol metabolites. Also, our research indicates that the red phenotype of oregano is a potential source of bioactive compounds for industrial developing of nutrient supplements.

Keywords: Origanum vulgare, red flower, phenotype, polyphenols