Phytochemical analysis and versatile in vitro evaluation of antimicrobial, cytotoxic and enzyme inhibition potential of different extracts of traditionally used Aquilegia pubiflora Wall. Ex Royle

Abstract

Background: Himalayan Columbine (Aquilegia pubiflora Wall. Ex Royle) is a medicinal plant and have been used as traditional treatments for various human diseases including skin burns, jaundice, hepatitis, wound healing, cardiovascular and circulatory diseases. Till now there is no report available on phytochemical investigation of Himalayan Columbine and to the best of our knowledge, through present study we have reported for the first time, the phytochemical analysis and pharmacological potentials of different leaf extracts of Aquilegia pubiflora.

Methods: Four types of extracts were prepared using solvent of different polarities (Distilled water AP_DW, Methanol AP_M, Ethanol AP_E and Ethyl acetate AP_EA), and were evaluated to determine the best candidate for potent bioactivity. Phytochemical constituents in prepared extracts were quantified through HPLC analysis. Subsequently, all four types of leaf extracts were then evaluated for their potential bioactivities including antimicrobial, protein kinase inhibition, anti-inflammatory, anti-diabetic, antioxidant, anti-Alzheimer, anti-aging and cytotoxic effect.

Results: HPLC analysis demonstrated the presence of dvitexin, isovitexin, orientin, isoorientin, ferulic acid, sinapic acid and chlorogenic acid in varied proportions in all plant extracts. Antimicrobial studies showed that, K. pneumonia was found to be most susceptible to inhibition zones of 11.2 ± 0.47, 13.9 ± 0.33, 12.7 ± 0.41, and 13.5 ± 0.62 measured at 5 mg/mL for AP_DW, AP_M, AP_E and AP_EA respectively. A. niger was the most susceptible strain in case of AP_DW with the highest zone of inhibition 14.3 ± 0.32, 13.2 ± 0.41 in case of AP_M, 13.7 ± 0.39 for AP_E while 15.4 ± 0.43 zone of inhibition was recorded in case of AP_EA at 5 mg/mL. The highest antioxidant activity of 92.6 ± 1.8 μgAAE/mg, 89.2 ± 2.4 μgAAE/mg, 277.5 ± 2.9 μM, 289.9 ± 1.74 μM for TAC, TRP, ABTS and FRAP, respectively, was shown by AP_E. AP_M, AP_E and AP_EA extracts showed a significant % cell inhibition (above 40%) against HepG2 cells. The highest anti-inflammatory of the samples was shown by AP_E (52.5 ± 1.1) against sPLA2, (41.2 ± 0.8) against 15-LOX, followed by (38.5 ± 1.5) and (32.4 ± 0.8) against COX-1 and COX-2, respectively.

Conclusions: Strong antimicrobial, Protein Kinase potency and considerable α-glucosidase, α-amylase, and cytotoxic potential were exhibited by plant samples. Significant anti-Alzheimer, anti-inflammatory, anti-aging, and kinase inhibitory potential of each plant sample thus aware us for further detailed research to determine novel drugs.

Keywords: Anti-aging; Anti-cancer; Antimicrobial; Flavonoids; HPLC; Inflammatory.

Fig. 1

Bioactive compounds detected in Aquilegia pubiflora leaf extracts

Fig. 2

a Protein kinase inhibitory potential, b image for AP_E kinase inhibition against Streptomyces 85E, c image for AP_M kinase inhibition against Streptomyces 85E, d image for AP_E use against K. pneumonia, e image for AP_E use against A. niger. Values are mean ± SD of triplicate. Where AP_DW, AP_M, AP_E and AP_EA stands for Distilled water, Methanol, Ethanol and Ethyl acetate extracts, respectively

Fig. 3

a Anti-inflammatory potential of medicinally important Aquilegia pubiflora extracts, b Anti-aging potential of Aquilegia pubiflora leaf extracts. Values are mean ± SD of triplicate. Where AP_DW, AP_M, AP_E and AP_EA stands for Distilled water, Methanol, Ethanol and Ethyl acetate extracts, respectively

Fig. 4

Cytotoxic potential of the Aquilegia pubiflora leaf extracts against the HepG2 cell line. Values are mean ± SD of triplicate. Doxorubicin was applied as positive control. Where AP_DW, AP_M, AP_E, AP_EA and NTC stands for Distilled water, Methanol, Ethanol, Ethyl acetate extracts and Non-Treated Cells, respectively