SBP 10 - Eco-Friendly Nanotechnology: Aloe Vera-Derived Antibacterial Agent and Food Preservation Innovations.

The increasing incidence of foodborne illnesses necessitates the development of novel antibacterial agents. This study investigates the comparative antibacterial activity of biosynthesized nanoparticles derived from Aloe barbadensis Miller (commonly known as Aloe vera) gel extract and its essential oil against common foodborne pathogens. Using a green synthesis approach, nanoparticles were synthesized and characterized using techniques such as UV-Vis spectroscopy

The project aims to provide an eco-friendly alternative to traditional physical and chemical methods for nanoparticle synthesis of antibacterial and preservation methods. By leveraging Aloe vera's natural reducing and stabilizing agents, it demonstrates the power of green nanotechnology to deliver sustainable solutions that reduce environmental impact, promote food security, and enhance public health. This leads to a novel approach towards addressing global issues of antibiotic resistance bacterial and food preservation through the sustainable synthesis of silver nanoparticles (AgNPs) and chitosan nanoparticles (CsNPs) using Aloe vera leaf extract and essential oil respectively. These nanoparticles exhibit potent antibacterial properties, effectively targeting both Gram-positive and Gram-negative bacteria. Additionally, CsNPs demonstrated a remarkable ability to extend the shelf life of fresh produce, such as cucumbers and potatoes, by reducing microbial growth.

The antibacterial efficacy of these nanoparticles was evaluated against key foodborne pathogens such as Bacillus cereus, Staphylococcus aureus, Salmonella enterica, Pseudomonas aeruginosa, and Pseudomonas fluorescens using the disc diffusion method (Kirby-Bauer test). Results showed that both Aloe vera gel extract and essential oil-derived nanoparticles exhibited significant antibacterial activity. However, nanoparticles derived from the gel extract had a higher inhibition rate compared to those from the essential oil. This enhanced antibacterial effect is attributed to the presence of bioactive compounds in Aloe vera that synergistically disrupt bacterial cell walls and inhibit metabolic pathways.

Key findings include significant inhibition zones for AgNPs against gram positive pathogens such as Staphylococcus aureus and Bacillus cereus, showcasing their robust antibacterial efficacy. Similarly, CsNP-treated produce retained freshness for over a week, showing up to a 70% reduction in spoilage compared to untreated samples.

This review extensively proves the antibacterial efficacy of  silver nanoparticles, therefore, there is a need to deepen the understanding of their synthesis, mechanisms of action against foodborne pathogens, and practical applications. Factors such as the size, surfactant, and structural shape of AgNPs significantly impact their distinctive physicochemical properties. Despite the numerous methods for producing AgNPs, green synthesis stands out for its high yield and biocompatibility, utilizing natural agents and safe chemicals.

The study highlights the potential of Aloe vera leaf extract-derived silver nanoparticles, which are more effective as antibacterial agents in food preservation and safety than essential oil/organic-derived chitosan nanoparticles. Further research is warranted to explore the mechanism of action and potential applications in food industry settings. The green synthesis approach, which uses Aloe vera as a natural reducing and stabilizing agent, represents a significant step toward sustainable nanotechnology. By avoiding hazardous chemicals and minimizing environmental risks, this method aligns with global priorities for eco-friendly innovation. The stability, efficacy, and multifunctionality of the synthesized nanoparticles validate Aloe vera as a valuable resource for producing nanomaterials.

For CsNPs, exploring their effectiveness across a wider variety of food products under real-world conditions is recommended. Testing their integration into active packaging systems can provide valuable data on their practicality and effectiveness in commercial applications. Collaboration among researchers, industry stakeholders, and regulatory agencies is essential to advancing the practical implementation of these findings. AgNPs and CsNPs have the potential to revolutionize current practices in food safety and antimicrobial resistance. AgNPs, for example, could be used in coatings for medical devices or food-contact surfaces, while CsNPs could enhance food packaging to reduce spoilage and extend shelf life. Public education about the benefits and safe use of these technologies can foster acceptance and support for further innovation.