Aerobic Microbiota of Neem (Azadirachta indica) Leaves: Possible Risks of Chewing Raw Neem Leaves
Bhoj R Singh*, Akanksha Yadav, Sinha DK, Vinodh Kumar OR and Karthikeyan R
Division of Epidemiology, ICAR-Indian Veterinary Research Institute, Izatnagar, India
*Corresponding Author: Bhoj R Singh, Principal Scientist, Division of Epidemiology, Modular Laboratory Building, ICAR-Indian Veterinary Research Institute, Izatnagar, India.
August 19, 2022; Published:September 30, 2022
Raw Neem (Azadirachta indica) leaves’ chewing is an often-recommended healthy practice in India, but little is understood about the microbial quality of leaves chewed. This study conducted to analyse the presence of potential microbiological hazards associated with Neem leaves. It was assessed through detection and antimicrobial resistance (A.M.R.) profiling of different aerobically growing bacteria using standard bacteriological methods. A total of 110 samples of Neem leaves collected from four localities (IVRI = 62, CARI = 10, Mahanagar = 18, and Suncity = 20) analysed yielded 357 bacterial isolates belonging to more than 63 species of 24 genera. Isolation of Gram-negative bacteria from samples of IVRI and CARI was significantly more frequent (p, < 0.05) than those from Mahanagar and Suncity, while the picture was in reverse for Gram-positive bacteria isolates. The most prevalent potentially pathogenic bacteria included Enterobacter (Pantoea) agglomerans detected in 37 samples, followed by Hafnia alvei (20), Escherichia coli (11), Serratia marcescens (8), Bacillus cereus (7), Raoultella terrigena (7), Serratia odorifera (7), Aeromonas bestiarum (4), Enterococcus faecium (2), Klebsiella oxytoca (2), K. pneumoniae (1), Pseudomonas aeruginosa (2), Acinetobacter ewofflii (1), Aeromonas caviae (1), Proteus mirabilis (1), Stenotrophomonas multophila (1), and Pseudomonas pseudoalcaligenes (1). In 26 samples, carbapenem-resistant (CR) and 72 samples, extended-spectrum β-lactamase (ESBL) producing bacteria were detected. Herbal antimicrobial drug resistance was also seen in a large number of bacterial isolates. The study indicated that A. indica leaves may be harbouring potentially pathogenic multiple drug-resistant bacteria, which may harm the health of leaves' consumers. Therefore, it may be suggested that a fresh A. indica leaves should only be consumed after proper cleansing and decontamination.
Keywords: Aerobic Microbiome; Microbiota of Neem Leaves; Escherichia coli; Carbapenem Resistance; ESBL; M.D.R; Klebsiella; Aeromonas; Enterococcus faecium
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