The Influence of Cultivars and Phenological Phases on the Accumulation of Nevadensin and Salvigenin in Basil{Ocimum basilicum)

Abstract

According to the earlier literature the optimum harvest time for basil is at the full flowering stage if accumulation of essential oil is taken into account. In this research we have investigated our gene-bank stored basil accessions to determine whether the harvest timing is variety specific or not considering their flavonoid accumulation pattern. In our work we have determined by HPLC the content of two main flavonoid compounds, salvigenin and nevadensin, of eight different gene bank accessions from 2013 of Ocimum basilicum L. Data were analysed with the nonparametric Kruskal-Wallis test. Multiple pairwise comparisons were made using the Conover-Iman procedure where the significance level was 5%. We have observed that the optimum harvest time is at the full flowering stage in the case of accessions 'Genovese' and 'Piros', but this was not verified for the others. The result of our experiment has shown that the maximum salvigenin and nevadensin content was detected both at the full-and early flowering period. Almost in all phenological phases the accession 'M. Grünes' accumulated the highest level of nevadensin, while accession 'Lengyel' produced the lowest results in all phenological phases. Generally it could be observed that compared with nevadensin more salvigenin is accumulated, and it is independent of the phenological phases. In the case of salvigenin, 'M. Grünes' accession produced the largest quantity and accession 'Dark Opal' showed the lowest values. Our analyses demonstrated that harvest at different phenological phases may result in different amounts of active agents according to the cultivar.

Extraction Processes Affect the Composition and Bioavailability of Flavones from Lamiaceae Plants: A Comprehensive Review

“…Polar solvents such as methanol, ethanol, and aqueous mixtures have been used to obtain extracts from species including O. basilicum, O. gratissimum, O. sanctum, and O. tenuiflorum with good results [84,[99][100][101][102][103][104]. Less used, but also effective in the extraction of flavones, are solvents such as diethyl ether, which is useful to extract such flavones as nevadensin and salvigenin in O. basilicum [105]. Fewer studies were observed with other solvents such as hot water extract that showed similar results to hydromethanolic and hydroethanolic extractions in the same plant [106].…”