Microwave-Assisted Improved Extraction and Purification of Anticancer Nimbolide from Azadirachta indica (Neem) Leaves

Abstract

Nimbolide, a limonoid present in leaves of the neem tree (Azadirachta indica), is an anticancer compound against a panel of human cancer cell lines. The rapid process of extraction and purification of the nimbolide from the leaves of neem tree through microwave-assisted extraction (MAE) coupled with a chromatographic technique was accomplished. The crude with a maximum content of nimbolide could be recovered from neem leaves through MAE. By using three-factors, three-level Box–Behnken design of response surface methodology (RSM), the optimal conditions for nimbolide extraction (R2 = 0.9019) were solid/liquid ratio 1:16 g/mL, microwave power 280 W, and extraction time 22 min. The enriched extract was further purified by a preparative thin-layer chromatography (PTLC), where nimbolide was obtained as 0.0336 g (0.67% yield, purity over 98%) with ethyl acetate/hexane = 4:6 in 3.0 h. Structural elucidation was performed through spectroscopic techniques, including FT-IR, 1H, and 13C-NMR. This method was simple and had a good potential for the purification of bioactive compounds from a natural product.

Optimized microwave-assisted azadirachtin extraction using response surface methodology

“…In general, the extraction efficiency of secondary metabolites depends on multiple factors, the most relevant being the nature of the plant material, polarity of the solvent, temperature, particle size generated during grinding, and extraction technique used, among others. These effects can be manifested independently or in combination [ 26 , [34] , [35] , [36] ]. For MAE-assisted extractions in hydroethanolic systems, it is essential to evaluate the effect of pH, extraction time, and voltage of the equipment used during extraction [ 36 , 37 ], since to date they have not been reported for RSM optimization processes using a BBD.…”

“…Most studies conducted on metabolite and oil extraction processes conform to second-order models [ 26 , 32 , 33 ].…”

“…Given the numerous uses of neem oil and its high commercial value, it is important to develop new methods and modify the existing methods for neem oil extraction that significantly reduce the extraction time, organic solvent consumption rate, and operating costs as well as improve extraction efficiency and maintain oil quality [ 23 ]. The optimal conditions for neem oil extraction using the RSM and MAE method have been determined in several studies [ [24] , [25] , [26] ], but, to our knowledge, the conditions for extracting neem seed oil in hydroethanolic media by MAE-assisted RSM with a BBD have not been reported. Therefore, the present study aims to optimize the conditions for the extraction of azadirachtin from neem seeds in a hydroalcoholic medium using the MAE-assisted RSM with a BBD.…”

Comparative Analysis of Stable Aqueous Dispersion of Silver Nanoparticle Synthesized from Mangifera Indica and Azadirachta Indica Leaf Extract

“…It is commonly known as Neem plant. According to neem plant is first seen in India and is abundant in nearby Indian subcontinents [22,23]. reported that Neem leaf is a source of bioactive secondary metabolites such as terpenoids, nimbidin gedunin azadirachtin etc [24].…”

Nimbolide, a Neem Limonoid, Is a Promising Candidate for the Anticancer Drug Arsenal

“…In addition, procurement, authentication, quality assurance, and scale-up are time-consuming and laborintensive. Recently, nimbolide was extracted using a simple, fast, and efficient microwave-assisted extraction method coupled with chromatography that yields 0.0336 g of nimbolide from 5 g of neem leaves within 3 h. 99 More such technical initiatives are necessary to promote the potential pharmaceutical applications of nimbolide. Evaluation of different routes of administration, solubility, gastrointestinal absorption, and bioavailability are critical parameters to be considered in drug development from natural sources.…”