Abstract
Azadirachta indica, commonly known as neem, is a well-recognized medicinal plant which is utilized for its antimicrobial, antifungal, and antiviral actions. Neem is mainly used in the Asian continent (India, China, etc.). Neem's potent antibacterial, antifungal, and antiviral properties are due to its diverse array of phytochemicals, which include limonoids (azadirachtin, nimbin, nimbidin), flavonoids (quercetin, kaempferol), tannins, and triterpenoids. These compounds act by several mechanisms, including disrupting microbial cell membranes, inhibiting vital metabolic enzymes, preventing biofilm formation, and inducing oxidative stress in pathogens. Neem extracts have shown promising inhibition against several microbial strains, including Candida albicans, Escherichia coli, Staphylococcus aureus, and Pseudomonas aeruginosa. The review concludes that neem is a promising candidate for developing safe, effective, and eco-friendly antimicrobial agents. However, further clinical studies, standardization, and regulatory validation are required. Future research should focus on targeted delivery systems, synergistic studies with conventional drugs, and its role in combating antimicrobial resistance (AMR). The main objective of this review is to study the botanical description, phytoconstituents and anti-microbial activity (anti-fungul, anti-viral, etc.) of neem.
Keywords
Neem, Anti-microbial, Infections, Phytochemical, Azadirachta indica
Introduction
Infectious illnesses caused by microbes such as bacteria, fungi, viruses, and parasites have accounted for most of the world's mortality and morbidity. The accelerated development of antimicrobial resistance (AMR) [1] has eroded the effectiveness of conventional antimicrobial therapy over time. The development of multidrug-resistant (MDR) pathogens over time has spawned an urgent need for new treatment techniques, especially those from natural origins with low tendencies for developing resistance. Natural sources, in this case, medicinal plants, have gained increasing attention as possible origins of bioactive compounds showing antimicrobial action [2]. One such crop that has exhibited tremendous potential as an antimicrobial agent is Azadirachta indica, commonly referred to as neem. Neem, native to the Indian subcontinent, has been used for centuries in traditional medicine for the treatment of various conditions, including fevers, infections, and inflammations [3]. Due to its extensive use in rural regions for the treatment of a variety of medical conditions, it is also referred to as the "village pharmacy" [4]. Neem contains a variety of bioactive compounds, including flavonoids, alkaloids, phenolics, and triterpenoids (e.g., azadirachtin), many of which possess potent antimicrobial activity [5,6]. Neem extracts have been reported to possess a broad spectrum of antibacterial, antifungal, antiviral, and antiparasitic activities [7]. These activities are attributed to a variety of mechanisms, including enzyme inhibition, protein and nucleic acid synthesis interference, and disruption of microbial cell membranes [8]. The clinical use of neem-derived antimicrobial therapies remains limited in spite of promising results from in vitro and in vivo studies due to problems with toxicity, bioavailability, and standardization [9]. This review seeks to consolidate what is known about neem's antimicrobial effects, emphasizing its active phytochemicals, modes of action, and possible use as a therapeutic substitute for treating infectious diseases.
Botanical description:
Azadirachta indica is a rapidly growing, evergreen tree belonging to the family Meliaceae. Neem is native to the Indian subcontinent but due to its multifaceted medicinal and ecological benefits, it is now cultivated on a large scale in tropical and subtropical regions of the globe. Neem typically grows to a height of 15 to 20 meters and bears a dense canopy of dark green leaves. Its leaves are pinnate with leaflets that are oblong and possess a very distinctive, strong aroma. It has yellowish fruit containing oily seeds and minute white flowers. Its bark is coarse and grayish-brown, but the most common parts used in medicine are its seeds and leaves [10,11]. Neem is a superior crop for agroforestry systems and pest control in the natural environment since it is insect-resistant and naturally well-suited to dry, arid climates. Due to its richness and widespread application in traditional medicine for various ailments, the tree is often referred to as the "village pharmacy" [12].
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Prashant Khare
Corresponding author
Sanjivani collage of pharmaceutical research and education, Kopargoan 423603, Maharashtra, India.
Shubham Kamble
Co-author
Matoshri collage of pharmacy, Nashik 422105, Maharashtra, India.
Prashant Khare*, Shubham Kamble, Antimicrobial Properties of Neem (Azadirachta Indica): A Comprehensive Review of Phytochemicals and Mechanisms of Action, Int. J. Sci. R. Tech., 2025, 2 (4), 646-654. https://doi.org/10.5281/zenodo.15295814
10.5281/zenodo.15295814
