Exploring Kinnow mandarin's hidden potential: Nature's key to antimicrobial and antidiabetic gold nanoparticles (K-AuNPs)

This pioneering study aims to address the paradox of the highly regarded Kinnow mandarin fruit, whose valuable peels have been considered undesired remnants from industrial fruit juice production. The study proposes the utilization of these discarded peels to synthesize ecologically safe gold nanoparticles (K-AuNPs) through a one-pot method. The objectives of this research are to synthesize K-AuNPs using an ecologically safe single-step approach, utilizing discarded Kinnow mandarin fruit peels, and to assess their antibacterial and antidiabetic potential. The validation of K-AuNPs involved various techniques including UV–visible spectroscopy, TEM, DLS, and zeta-potential investigations. The antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis was compared to levofloxacin and Kinnow mandarin aqueous peel extract (KAPE). Furthermore, the anti-diabetic efficacy was evaluated through α-amylase and α-glucosidase experiments, comparing K-AuNPs to pure KAPE and the standard inhibitor acarbose. The results confirmed the successful synthesis of K-AuNPs from KAPE, as evidenced by UV-spectral profiles (527 nm), TEM micrographs (∼21 d. nm), dynamic light scattering (65 d.nm), and zeta-potential (-12 mV). The K-AuNPs demonstrated a superior zone of inhibition and lower MIC values against Escherichia coli, Pseudomonas aeruginosa, and Bacillus subtilis, surpassing levofloxacin and KAPE alone. Additionally, the K-AuNPs exhibited potent anti-diabetic efficacy, outperforming both pure KAPE and acarbose at a lower dosage. To sum up, the process of producing K-AuNPs utilizing Kinnow mandarin peel extracts demonstrates a powerful antibacterial and antidiabetic remedy sourced from previously discarded materials. These findings signify a significant leap forward in the domain of natural product exploration, with the potential to fundamentally reshape modern healthcare approaches.