Polysaccharides from Dolichos biflorus Linn and Trachyspermum ammi Linn seeds: isolation, characterization and remarkable antimicrobial activity

Shibani Basu,Rupam Kumar Bhunia,Bimal K Banik,Jhuma Ganguly,Manojit Ghosh

doi:10.1186/s13065-017-0349-2

Abstract

Polysaccharides are structurally complex and essential constituents of life, and therefore, studies directed to these kinds of molecules have received scientific attention. Despite an easy availability of Dolichos biflorus Linn and Trachyspermum ammi (Linn) seeds isolation, characterization and antimicrobial studies of polysaccharides derived from these two natural sources have not been investigated. Therefore, we report here isolation of polysaccharides, their purification and characterization from Dolichos biflorus Linn and Trachyspermum ammi (Linn) seeds. Gel permeation chromatography, GC–MS, SEM, XRD, EDX and FT-IR analyses show the presence of three pentose sugar such as d-ribose, d-arabinose, d-xylose and hexose sugar such as d-mannose, d-galactose and d-glucose. Unprecedented antimicrobial activity of these polysaccharides against Gram positive bacteria such as Staphylococcus aureus and Bacillus subtilis and Gram negative bacteria such as Escherichia coli and Pseudomonas aeruginosa are established.

Highlights

There has been tremendous interest in the use of medicinal plants in developed as well as developing countries, because compounds obtained from medicinal plants have been shown to be effective sources of therapeutic agents, without undesirable side effects [1, 2]
Isolation and purification by gel permeation chromatography (GPC) on a Sephadex G-25 column (600 × 16 mm) obtained UV actives region peaks for the phenol sulfuric acid assay (Fig. 2) from T. ammi water extract (TAE) and D. biflorus water extract (DAE)
The GC and GC–MS analyses showed the presence of three pentose sugars such as d-ribose, d-arabinose, d-xylose and three hexose sugars such as d-mannose, d-galactose and d-glucose in TAE (Fig. 4)

Summary

Introduction

There has been tremendous interest in the use of medicinal plants in developed as well as developing countries, because compounds obtained from medicinal plants have been shown to be effective sources of therapeutic agents, without undesirable side effects [1, 2]. Current studies have proved that the structures of polysaccharides are closely related to their biological activities [3]. Known as bishop’s weed, it is an aromatic spice closely resembling thyme in flavor [4]. It is a native of Egypt and is distributed in the Mediterranean region and South-west Asia. It has long being used as the principal source of thymol T. ammi seeds and is employed as an antiseptic, aromatic, carminative and antioxidant source [5]. It has been reported to possess strong insecticidal activity, bronchodilatory effect on asthmatic airways and analgesic effect [7,8,9]

Methods

Results

Conclusion