Research and analysis of nanoparticles (NPs) synthesis and their biological activities has been expanded significantly in the recent years. The agents used for nanoparticles (NPs) synthesis are of organic (mainly carbon) and inorganic (metal ions like silver and gold) origin (Singh et al., 2010). Among these, silver (Ag) is the most preferred NPs synthesis agent due to its reported use in medical field as best topical bactericides from ancient times (Lavanya et al., 2013). The stable silver nanoparticles had been synthesized by using soluble starch as both the reducing and stabilizing agents (Shrivastava et al., 2012). So the concern of scientific community shifted towards ecofriendly, natural and cheaper method of NPs synthesis by using microorganisms and plant extracts (Mohanpuria et al., 2008). The use of plant materials for silver nanoparticles (AgNPs) is most popular due to its potential biological activities, easy availability and faster rate of synthesis there by cutting the cost of NP's synthesis (Huang et al., 2007 and Salam et al., 2012). The nanoparticles had been clinically used for infection, vaccines and renal diseases (Malhotra et al., 2010). The plant extract of petals of herbal species like Punica granatum, Datura metel (Chandran et al., 2011) and stem extracts of Svensonia hyderobadensis (Linga et al., 2011) had been effectively used for AgNPs synthesis and investigated for their antimicrobial activities.
Nanoparticles could be synthesized by various approaches like photochemical reactions in reverse micelles (Taleb et al., 1997), thermal decomposition (Esumi et al., 1990), sonochemical (Zhu et al., 2000) and microwave assisted process (Santosh et al., 2002 and Prasher et al., 2009). Nanocrystalline silver particles have found tremendous applications in the field of high sensitivity biomolecular detection and diagnostics (Schultz et al., 2000), antimicrobials and therapeutics (Rai and Yadav., 2009 and Elechiguerra et al., 2005) and micro-electronics (Gittins et al., 2000).
Acacia auriculiformis A. Cunn. is an exotic species that can survive in degraded lands in Thai savanna (Badejo et al., 1998). Besides its high adaptability in degraded savanna areas, A. auriculiformis is known for its nitrogen fixation property (Sprent and Parsons, 2000) enriching macrofaunal composition (Mboukou-Kimbatsa et al., 1998), low allelopathic effects (Bernhard-Reversat et al., 1999) and ability to pump nutrients from the subsoil (Kang et al., 1993).
Table of Contents
1. INTRODUCTION
2. METHANOL EXTRACT AND SILVER NANOPARTICLES
3. ACETONE EXTRACT AND SILVER NANOPARTICLES
4. WATER EXTRACT AND SILVER NANOPARTICLES
5. LITERATURE CITED
Research Objectives & Core Topics
The primary research objective of this work is to investigate a green synthesis methodology for producing silver nanoparticles (AgNPs) using the bark extract of the medicinal plant Acacia auriculiformis, followed by a comprehensive comparative evaluation of their antimicrobial and antioxidant potential against crude plant extracts.
- Green synthesis of silver nanoparticles from A. auriculiformis bark.
- Physicochemical characterization using UV-Vis, FTIR, PL, and XRD spectroscopy.
- Comparative antimicrobial assays against Gram-positive and Gram-negative bacteria.
- Evaluation of antioxidant capacity through various biochemical assays (DPPH, Hydrogen Peroxide scavenging, etc.).
Excerpt from the Book
INTRODUCTION
Research and analysis of nanoparticles (NPs) synthesis and their biological activities has been expanded significantly in the recent years. The agents used for nanoparticles (NPs) synthesis are of organic (mainly carbon) and inorganic (metal ions like silver and gold) origin (Singh et al., 2010). Among these, silver (Ag) is the most preferred NPs synthesis agent due to its reported use in medical field as best topical bactericides from ancient times (Lavanya et al., 2013). The stable silver nanoparticles had been synthesized by using soluble starch as both the reducing and stabilizing agents (Shrivastava et al., 2012). So the concern of scientific community shifted towards ecofriendly, natural and cheaper method of NPs synthesis by using microorganisms and plant extracts (Mohanpuria et al., 2008). The use of plant materials for silver nanoparticles (AgNPs) is most popular due to its potential biological activities, easy availability and faster rate of synthesis there by cutting the cost of NP's synthesis (Huang et al., 2007 and Salam et al., 2012).
Nanoparticles could be synthesized by various approaches like photochemical reactions in reverse micelles (Taleb et al., 1997), thermal decomposition (Esumi et al., 1990), sonochemical (Zhu et al., 2000) and microwave assisted process (Santosh et al., 2002 and Prasher et al., 2009). Nanocrystalline silver particles have found tremendous applications in the field of high sensitivity biomolecular detection and diagnostics (Schultz et al., 2000), antimicrobials and therapeutics (Rai and Yadav., 2009 and Elechiguerra et al., 2005) and micro-electronics (Gittins et al., 2000).
Summary of Chapters
1. INTRODUCTION: Provides an overview of nanoparticle synthesis methods, emphasizing green synthesis using plant extracts, and introduces the medicinal properties of Acacia auriculiformis.
2. METHANOL EXTRACT AND SILVER NANOPARTICLES: Details the synthesis and characterization of silver nanoparticles using methanol extracts of A. auriculiformis and analyzes their antimicrobial and antioxidant effectiveness.
3. ACETONE EXTRACT AND SILVER NANOPARTICLES: Examines the experimental results of using acetone-based bark extracts to synthesize silver nanoparticles and compares their bioactivity to the crude extract.
4. WATER EXTRACT AND SILVER NANOPARTICLES: Focuses on the green synthesis of nanoparticles using water-based extraction and evaluates their specific performance in antimicrobial and antioxidant assays.
5. LITERATURE CITED: A comprehensive collection of academic references and research studies utilized throughout the thesis.
Keywords
Silver nanoparticles, AgNPs, green synthesis, Acacia auriculiformis, antimicrobial activity, antioxidant capacity, plant extract, methanol extract, acetone extract, water extract, biosynthesis, UV-Visible spectroscopy, FTIR, nanotechnology.
Frequently Asked Questions
What is the core focus of this research?
The research focuses on the green synthesis of silver nanoparticles (AgNPs) using bark extracts of the plant Acacia auriculiformis as a natural and eco-friendly reducing agent.
What are the primary fields explored in this study?
The study covers nanotechnology, phytochemistry, and microbiology, specifically focusing on the bioactivity of synthesized nanoparticles and their potential therapeutic applications.
What is the main objective of this thesis?
The objective is to synthesize AgNPs using three different solvents (methanol, acetone, water), characterize them using spectroscopic techniques, and compare their antimicrobial and antioxidant potential against the crude extracts.
Which scientific methods are employed for synthesis and analysis?
The study uses maceration extraction, green synthesis through chemical reduction, and characterization via UV-Vis, FTIR, and Photoluminescence spectroscopy. Biological activity is assessed using agar well diffusion and antioxidant biochemical assays.
What content is covered in the main chapters?
The main chapters detail the experimental protocols and results for each solvent-specific extract, including the physical characterization of the produced AgNPs and their measured bio-efficacy.
Which keywords best characterize this work?
Key terms include green synthesis, AgNPs, Acacia auriculiformis, antimicrobial activity, antioxidant capacity, and biosynthesized nanoparticles.
How does the polarity of the solvent affect the antioxidant potential?
The results suggest that solvent polarity plays a critical role, as higher polarity often correlates with the extraction efficiency of polyphenols and flavonoids, which contribute significantly to the antioxidant scavenging potential of the synthesized AgNPs.
What specific role does A. auriculiformis bark play in this synthesis?
The bark serves as a rich source of polyphenols and tannins, acting as both a reducing and a capping agent in the green synthesis process, which facilitates the stable formation of silver nanoparticles.
- Quote paper
- Dr Amandeep Kaur (Author), Dr Devinder Singh (Author), 2013, Bioactivity of Green Synthesised Silver Nanoparticles, Munich, GRIN Verlag, https://www.grin.com/document/295643
