Dr. Neena Arora

Minor Research Project
Funded By UGC, 2015-2017
F.No.: MS-124/102054/XII/14-15/CRO

Executive Summary

Extraction, Isolation and Identification of Bioactive Compounds from Some Medicinal Plants of Madhya Pradesh : An Alternative Therapy for Health Benefit

Medicinal plants are a source of naturally active compounds used extensively by tribal people worldwide for many ailments. These are the reservoirs of potentially useful chemical compounds that could serve as newer leads and clues for modern drug design. The most important of these bioactive constituents of plants are alkaloids, tannins, flavonoids and phenolic compounds. Correlation between the phyto-constituents and the bioactivity of plant is desirable to know for the synthesis of compounds with specific activities to treat various health ailments and chronic diseases as well.
Many plants respond to environmental stress by producing antioxidants such as polyphenols. These absorb and neutralize free radicals, quenching singlet and triplet oxygen, or inducing expression of peroxides and other toxic metabolites. The medicinal value of plants is related to their phytochemical component and secondary metabolites including: phenolic compounds, flavonoids, alkaloids, tannins and other stress gene response products.
The medicinal plants appear to be rich in metabolites widely used in traditional medicine to combat and cure various ailments. The distribution of metabolite within a plant both between tissues and during growth and development
 is rarely uniform..Acacia arabica and Catharanthus roseus plants are rich source of phytochemicals and have great medicinal value and have been used in folk medicines and Ayurveda. Hence this study is an attempt to estimate secondary metabolites from two plants i.e. Acacia arabica (Babool) and Catharanthus roseus(Sadabahar)in different solvents using conventional soxhlet method and modern microwave assisted method and find out their antioxidant and antidiabetic  activity.

The various results obtained during the investigations are as follows: 

  • Microwave assisted extraction enhances the extraction efficiency as compared to conventional extraction technique. Maximum extraction yield of 19.63% in Acacia arabica and 21.3% in Catharanthus roseus was found in aqueous microwave assisted leaf extract.
  • Phytochemical screening of extract of Acacia arabica leaf, bark and flower and Catharanthus roseus leaf and flower in different solvent with two different methods i.e Soxhlet & Microwave assisted extraction method clearly reveals that the maximum classes of phyto-constituents were present in aqueous and ethanolic extract as compared to extract in other solvents.
  • Phytochemical screening of the different extract indicates more phytoconstituents in microwave-assisted extracts than in extract obtained through Soxhlet extraction.
  • Methanolic extract of Catharanthus roseus leaves contains high intensity of alkaloids, tannins, steroids and saponins.
  • The Yield of Total phenolic component(TPC), Total flavanoid component (TFC), Total tannin component (TTC), and Total alkaloid component (TAC) were affected by the method of extraction and the solvent used; and the best results were obtained with the solvent ethanol / methanol using microwave assisted extraction method.
  • Total phenolic compounds in different part of the plant with different solvent were observed in the following decreasing order:

Leaf – Water>Ethanol > Ethyl acetate> Chloroform
Bark – Ethyl acetate>Ethanol > Water >Chloroform
Flower – Water >Ethanol > Ethyl acetate> Chloroform

  • Methanolic extract of flowers of catharanthus has shown highest amount of total phenolic content (45.667mgGAE/g) as compared to others.
  • The use of microwave power can enhance the percent yield of the Phyto-constituents hence economic, green, safe and recommended for extraction of secondary metabolites from the plant extract.
  • The DPPH radical scavenging assay was used to assess the antioxidant ability of various plants extracts of Acacia arabica. The IC50values for leaves, bark and flowers extracts in different solvents ranged from 76.01 to 238.20, 67.16 to 256.88 and 86.34 to 314.32 μg/mL respectively.
  • The microwave assisted aqueous extract of Catharanthus roseus has shown highest amount of NO scavenging potential in terms of percent inhibition (64.221) as compared to others. Microwave assisted ethanolic bark extract of Acacia arabica  showed the highest α-amylase inhibitory activity.
  • Silver nanoparticles were also synthesized using aqueous leaf extract of Acacia arabica  and Catharanthus roseus and found effective against S.mutans.

The antioxidant activity exhibited by the extracts of Acacia arabica and Catharanthus roseus could justifies the ethnotherapeutic usage of these plant by the traditional healers. The results from the present study indicates that it would be highly economical for the production of potential antioxidant supplements.
The present study can be used in future for the economical formulation of the active chemical ingredients in natural drugs against variety of neurological and inflammatory diseases.