Traditionally used edible Solanaceae plants of Mizoram, India have high antioxidant and antimicrobial potential for effective phytopharmaceutical and nutraceutical formulations

Heliyon. 2021 Sep 1;7(9):e07907. doi: 10.1016/j.heliyon.2021.e07907. eCollection 2021 Sep.

Abstract

Ethnopharmacological relevance: Solanaceae plants have been used as traditional medicines in Mizoram, India. This warrants the presence of therapeutic compounds and various bioactive phytochemicals in these plants, and characterizing their structures could lead to a possible focus for drug development.

Aim of the study: Solanaceae plants are incredible sources of proteins and minerals; some even have high medicinal values which has been recognized traditionally. The present study was designed to explore and document the ethnobotany, phytochemical and mineral nutrient composition, antimicrobial properties, antioxidant potential and to identify functional groups from edible species of Solanaceae from Mizoram, India.

Materials and methods: Field surveys and samples collection was conducted from Aizawl District, Mizoram, India. All the studied samples were extracted using Soxhlet apparatus for the analysis of bioactive compounds. The total phenol, total flavonoid and total anthocyanin contents were determined using standard methods. The antioxidant activities were measured using DPPH free radical scavenging, APX, CAT and SOD activities. The proximate analyses and mineral contents were determined by standard methods. The antibacterial potential was determined using the agar well diffusion method, and the functional groups were analysed using FTIR. All the results were reported as the mean ± standard deviation. The linear regression coefficient (R2) for total flavonoid and phenolic content with antioxidant activity was analysed using Graph Pad Prism Version 5. P-value < 0.05 was considered significant.

Results: The phytochemical screenings showed the presence of alkaloids, tannins, flavonoids, terpenoids and saponins in all the samples. The highest total phenolic content was found in Solanum anguivi Lam. (29.51 mg GAE/g), and Capsicum annuum L. contained the highest total flavonoids (35.15 ± 0.03 mg/g). Proteins and carbohydrates contents were found to be the highest in Solanum melongena L. (28.49 mg/g) and Physalis angulata L. (35.64 mg/g) respectively. Elemental analysis showed the presence of Calcium (Ca), Copper (Cu), Iron (Fe), Manganese (Mn), Zinc (Zn), Potassium (K), Magnesium (Mg) and Sodium (Na) in high proportion in all the studied samples. All the plant extracts showed effective antibacterial activities against Bacillus subtilis, Escherichia coli and Pseudomonas aeruginosa. The Fourier Transformed Infra-Red Spectroscopy (FTIR) spectra revealed multiple functional groups in these plants species which could be used to identify bioactive compounds that can be subsequently utilized as herbal remedies for various ailments.

Conclusion: Our findings suggest that a considerable amount of nutrients, biologically active and therapeutic compounds are present in the studied samples and these plants could be potential sources for new phyto-pharmaceutical and nutraceutical preparations.

Keywords: Antimicrobial; Bioactive phytochemicals; Ethnobotany; FT-IR; Mizoram; Solanaceae.