Clinal variation in phytochemical constituents of Pinus roxburghii Sargent morphotypes distributed in Western Himalayas and exploration of its antibacterial and antioxidant activity

Abstract

newline ix newlineAbstract newlinePinus roxburghii Sargent is a dominant species of mid to high Himalayas, withstands harsh and xeric conditions because of its phenotypic plasticity. The crown of this species displays two morphotypes i.e. dark green and light green which is influenced by environmental factors especially clinal variation. This species is of great economic importance due to presence of high quality phytochemical constituents and hence has multipurpose usage as food, veterinary medicine, dye, perfumery etc. Hence, the present investigation is carried out on its two morphotypes for identifying the superior natural stand rich in phytochemical constituents and possesses high biological activity. newlineHimachal Pradesh constitutes the study area for sampling, which was divided into three provinces according to latitude 30°-31°N (Solan), 31°-32° N (Mandi), 32°-33° N (Kangra) representing three sample sites. Each province was further divided into three altitudinal clines i.e. (upto 1000 m, 1000-1500 m, 1500-2000 m). From each altitudinal cline the research material (needles and bark) was collected from five trees representing two morphotypes (dark green and light green). Samples from different populations with varying altitudes were subjected to qualitative and quantitative estimation for the presence of various phytochemicals by using various spectrophotometric and GC-MS techniques. newlineAnalysis reflected statistically significant differences with altitudinal and latitudinal clines. Dark green morphotype was dominant over light green morphotype in all parameters. Bark extract of both morphotype showed highest phytochemical constituents and biological potential than needle part of this species. Results of fractionation showed that phenolic and flavonoid content was observed maximum in n-Butanol fraction of dark green bark morphotype (Table 4.20-4.22). GC-MS analysis identified total 31 compounds in n-Butanol fraction of four different types of morphotypes of P. roxburghii. 12 compounds were identified in dark green bark morphotype (Table 4.38), 17 compounds were identified in dark green leaves (Table 4.39), 9 compounds were identified in light green bark morphotype (Table 4.40) and 17 compounds were identified in light green leaves (Table 4.41). newlineThe results revealed that phytochemicals such as phenols, flavonoids and alkaloids were present in all the sampled populations but their quality and quantity varied significantly in different reaches. This assessing of phytochemical content of two morphotype of this species at varying altitudes can help to select elite genotype and reflect the best suited altitude for commercial purposes as these phytochemicals are considered as the basis for their medicinal activity. newlineKeywords: Metabolites, altitude, morphotype, clines, biological potential, P. roxburghii.