Antibacterial potential and ethnomedical relevance of Kumaun Himalayan Gymnosperms

Abstract

Ethnomedicinal information is one of the powerful criteria for new drugs discoveries therefore; present investigation was carried out to evaluate the ethnomedicinal and antibacterial potential of traditional Kumaun Himalayan gymnosperms. Besides, an antibacterial value index and relative antibacterial activity of studied plants have been established. Forty four plant leaves extracts in different organic solvents (methanol, ethanol, chloroform and hexane) of 11 gymnosperms (Araucaria cunninghamii, Biota orientalis, Cedrus deodara, Cephalotaxus griffithi, Cryptomeria japonica Cupressus torulosa, Ginkgo biloba, Juniperus communis, Picea smithiana, Pinus wallichiana and Taxus baccata) occurring in Kumaun Himalaya were screened for their antimicrobial activity against five pathogenic bacteria using disc diffusion method. The antibacterial activity of studied gymnospermic plant extracts against a panel of bacteria was found effective at 1000 µg/ml. The MIC and MBC values of each extract (where ZOI ≥ 15 mm) were also determined. The methanol extract of screened gymnosperms were found the most effective against all the bacteria (54% to 81%), followed by ethanol extract (45-72%), hexane extract (18-27%), while in chloroform extract it ranged 9-27% only. The extracts of G. biloba exhibited superior Relative Antibacterial Activity (RAA, 20%), followed by A. cunninghamii and P. wallichiana (12% RAA, each). The lowest RAA value was observed for C. torulosa (1%). All data were also analyzed for determination of an Antibacterial Value Index (ABVI) for each studied species of gymnosperm. G. biloba had maximum ABVI i.e. 90 % followed by A. cunninghamii and P. wallichiana (ABVI, 55% each). C. torulosa showed the least ABVI and RAA i.e. 5% and 11%, respectively. The present work fully highlighted the utility of traditionally known 11 gymnosperms of Kumaun Himalaya for their antibacterial activities against pathogenic bacteria.

Screening for the Biochemical Profile and Biological Activity in Cephalotaxus and Taxus Collected from North-Eastern Himalayas

“…They reported significant activity against E. coli and S. aureus. Joshi et al 32 investigated the anti-bacterial activity of methanolic and ethanolic extracts of Cephalotaxus leaves and methanol, ethanol, and chloroform extracts of Taxus leaves and discovered that methanolic extract had the strongest antibacterial effect. It is the high gallic acid content that contributes to the moderate anti-bacterial potential of Gram- negative bacterial species such as E. coli and EC DH5-a, 48 while Muhammad et al 33 stated that the existence of alkaloids, phenols, polyphenols, saponins, tannins, anthraquinones, steroids, and particularly diterpenes can attributed to this anti-microbial action.…”

“…These two plants are of great ethnobotanical significance. The tribal people of the northeastern Himalayas and surrounding areas of India use them extensively and in a variety of ways, but little is known about the biological activities of these two genera. − The objective of the current study is to compare the biological activities present in the aerial parts of Cephalotaxus and Taxus.…”

There Is Not Only Cupressus sempervirens L.: A Review on the Phytochemistry and Bioactivities of the Other Cupressus L. Species

“…Different extracts of the needles of this species collected in India exert moderate to good antioxidant activities according to the DPPH, ABTS and SSA assay with IC 50 values from 34.93 to 83.83 µg/mL [130]. The methanolic extract of the leaves collected in Himalaya exerts modest antibacterial activities against Agrobacterium tumefaciens MTCC609, Escherichia coli MTCC40 and Xanthomonas phaseoli with MIC values of 250, 500 and 500 µg/mL, respectively [174]. The leaf ethanolic extract of this species collected in India shows effects against Pectobacterium carotovorum subsp.…”

Phytochemistry and Therapeutic Potential of Cupressus torulosa Needles Essential Oil from India

“…Despite the numerous traditional uses, there is a scarcity of scientific studies investigating the biological potential of the needles derived essential oil of C. torulosa . Only a handful of in vitro studies have been conducted to assess the antioxidant, antibacterial, and antifungal properties of different extracts derived from the needles of C. torulosa [20–23] . Moreover, the EO itself has primarily been evaluated for its antibacterial and antifungal potential, [18,24] demonstrating moderate activity against various tested bacterial strains, including Aspergillus niger, A. terreus, Candida spp., Trichophyton rubrum, T. mentagrophytes, Microsporum canis, Pencillium crysogensum, P. expansum , and P. griseofulvum .…”