A Comparative Study on Dye Degradation by Leaf and Root Extracts of Parthenium hysterophorus L

Dipesh Shahi,Rajiv Sapkota

doi:10.3126/ijasbt.v6i4.22110

Abstract

The use of different dyes and pigments is increasing with the increase in industrialization leading to the high production of effluent. The effluent contaminated with dyes and dye-stuff has harmful effects on public health and the environment. Thus, the treatment of effluent is essential. Biological approaches are gaining much interest due to their cost-effective and eco-friendly nature over various physicochemical methods for the treatment of dye-contaminated wastewater. This study highlights on the biodegradation of congo red and malachite green by using leaf and root extracts of Parthenium hysterophorus. The extract and the dye were mixed in the ratio of 1:2 and incubated at 40ºC for 90 minutes. Decolorization assay was performed using UV visible spectrophotometer which indicated that decolorization was due to degradation of dyes into non-colored metabolites. The leaves extract exhibited higher decolorizing activity than roots extract. The maximum decolorization for leaves extract was 55.8% (congo red) and 51.6% (malachite green). Furthermore, phytotoxicity test was carried out to determine the effect of dyes and their degradation metabolites on seed germination and seedling growth of chickpea (Cicer arietinum L). The germination percentage and seedling growth were more in degradation metabolites than untreated dyes, indicating less toxic nature of degradation metabolites. Hence, it can be inferred that P. hysterophorus extracts can be used to treat dye wastewater and treated wastewater can be used for irrigation. Int. J. Appl. Sci. Biotechnol. Vol 6(4): 327-331

Highlights

Dyes have become an inseparable part of human life due to their applications in different industries, such as textile, food, cosmetic, paint, paper, beverage, polymer, pharmaceutical etc. in order to impart colors to various products
Various physicochemical methods have been employed for the treatment of industrial wastes containing different dyes and dye-stuff, these methods are very costly and end up producing recalcitrant wastes
The UV visible spectrophotometer indicated that decolorization was due to biodegradation of dyes into non-colored metabolites

Summary

Introduction

Dyes have become an inseparable part of human life due to their applications in different industries, such as textile, food, cosmetic, paint, paper, beverage, polymer, pharmaceutical etc. in order to impart colors to various products. The different types of physicochemical methods such as flocculation, froth floatation, membrane filtration, ozonation, reverse osmosis, adsorption, and electrocoagulation have been employed for decolorization of wastewater dyes (Gupta et al, 2004; Gupta et al, 2006) These methods are costly, less efficient and produce hazardous wastes which are recalcitrant in nature. We have focused on the biodegradation of two most commonly used dyes: congo red and malachite green by using leaf and root extracts of Parthenium hysterophorus. Congo red is an acidic diazo dye whereas malachite green is a basic triphenylmethane dye These dyes have been used as coloring agents in different industries and have harmful effects on public health and the environment. The comparative study on dye decolorization by leaf and root extracts has been carried out along with phytotoxicity test to analyze the effect of dyes and their degradation metabolites on seed germination and seedling growth of chickpea (Cicer arietinum L)

Materials and Methods

Results and Discussion

Conclusion