Solvent-free Microwave Extraction Research Articles

Chemical Composition of Algerian Pinus halepensis Mill. Essential Oils Obtained by Hydrodistillation and Solvent-Free Microwave Extraction Methods and Their Biological Activities

Chemical Composition of Algerian Pinus halepensis Mill. Essential Oils Obtained by Hydrodistillation and Solvent-Free Microwave Extraction Methods and Their Biological Activities

Recent Development on the Extraction Process of Plants Essential Oil and its Effect on Chemical Composition: A Review

This study presents a thorough review on different innovative extraction techniques of different plant essential oil derived from its peel, leaves, seeds and shrubs. The review also entails the different pre-treatment processes that affects the quality and recovery of the plant essential oil. Also, discussed the recently developed green extraction method such as Microwave Assisted Hydrodistillation (MAHD), Solvent Free Microwave Extraction (SFME), Ultrasound Assisted Extraction (UAE), Supercritical Fluid Extraction (SFE) and Ohmic Heated Assisted Hydrodistillation (OHAD). The impact of these extraction process on the important chemical composition of essential oil is further analyzed in this review. The important parameters in extraction is also studied such as the water to material ratio, extraction temperature, power input and extraction time. Based on the different articles reviewed, it signifies that the innovative extraction method improves the quality and quantity of the essential oil yield. It also improved the number of component that can be extracted in the plant essential oil and its biological activities such as antioxidant and antimicrobial activities. Thus this review aims to emphasize the potential of the newly developed essential oil extraction techniques that would help to boon the pharmaceuticals, food and agriculture industry.

Amalgamating the research footprints of Prof. Farid Chemat and decoding its essence – A teaching manual on eco-extraction of botanicals

Professor Farid Chemat (Université d’Avignon, France) was a great scientist in the field of green extraction of botanicals who passed away in 2023. He was the man behind the ‘eco-extraction’ mission of botanicals. Prof. Farid had developed various eco-extraction models namely, solvent-free microwave extraction protocol, microwave hydrodiffusion and gravity protocol dedicated especially for essential oil extraction. The basic purpose of this review is to pay scientific tribute to the legendary scientist by amalgamating his research footprints on eco-extraction and consolidating the same into a teaching manual for young researchers inclined towards green extraction of botanicals. Data mining was performed from SCOPUS and navigated as per the inclusion criterion. The authors have critically opined on the preference of plant, plant family, plant part and eco-extraction models used by Prof. Farid. A summary of critical learning from Prof. Farid's work have been presented along with bibliometric analysis to understand his collaboration networking.

Screening of the compositions of essential oils and volatiles of Perovskia abrotanoides Karel. along with antioxidant, antibacterial and cytotoxic impacts of its methanol extract

In the present report, a combination of classical and advanced methods, namely classical hydrodistillation (HD) and solvent free microwave extraction (SFME) have been used for the extraction of essential oils from flowers, leaves and stems of Perovskia abrotanoides Karel. as an endemic plant to Golestan Province, Iran. The volatile fractions from the same plant organs have been separated using a solid phase microextraction (SPME) fibre and characterised using a GC/MS apparatus. Moreover, oxygenated monoterpenes, for example, 1,8-cineole and borneol were found as the most constituent components of the majority of the characterised profiles. Accordingly, for flowers, leaves and stems of P. abrotanoides Karel., the relevant quantities were HD: 12.0 and 12.4, 24.0 and 17.9, 12.9 and 16.8%; SFME: 15.6 and 15.2, 20.5 and 16.2, 13.5 and 14.7%; SPME: 20.9 and 5.2, 25.5 and 9.9, 26.4 and 8.5%, respectively. Total phenolic content (TPC: 52.02 mg GAE/g), total flavonoids content (TFC: 98.46 mg QE/g) as well as antioxidant and antibacterial effects of the extract from the aerial parts of this species have been also evaluated. The cytotoxicity of Perovskia abrotanoides Karel. MeOH extract has been tested against HUVECs cell line. Moreover, our study on the in vitro anti-bladder carcinoma demonstrated that the plant extract reduced the viability of malignant bladder cell line, in a dose dependent way.

Extraction of essential oil from fresh basil leaves (Ocimum basilicum L.) using solvent-free microwave extraction method: Extraction parameter optimization, electric consumption, and CO2 emission study

Essential oil extraction is often still done using conventional methods. This process requires a long time, a lot of energy, and a large amount of solvent. Therefore, solvent-free microwave extraction (SFME) was chosen as a better and greener alternative. The objectives of this study were: (i) to determine the optimum conditions for basil oil extraction in the SFME method using Box-Behnken Design (BBD) and (ii) to analyze the electric consumption and CO2 emissions produced during the extraction process. The results showed that microwave power, F/D ratio, and extraction time to obtain optimum conditions were 600 W, 100 g/L, and 18.12 min, respectively. Extraction using hydro distillation (HD) method consumes 1 kWh of electricity and produces 0.80 kg of CO2 emission more than the SFME method. The yield of essential oil carried out using SFME method produces more oil than the HD method. The use of less energy and more optimal results make the extraction process with SFME greener and environmentally friendly.

Methodology for Extraction of Essential Oils: A Review

The majority of concentrated and volatile Essential oils are extracted from various parts of the plants. Essential oils contain hundreds of organic constituents such as natural elements, vitamins, hormones, etc., widely used in the perfumery and pharmaceutical industries. Different techniques are available for the extraction of essential oil, such as hydro and steam distillation, cold pressing/expression, Maceration, solvent extraction, Effleurage, Carbon Dioxide Extraction, Hydro Diffusion, etc., and innovative techniques like Supercritical Fluid Extraction (S.F.E.), Microwave Assisted Hydro distillation (MAHD), Ultrasound-Assisted Extraction (U.A.E.), Solvent-free Microwave Extraction (SFME), Microwave hydro diffusion and Gravity (M.H.G.). This review paper summarizes the research on various methods for essential oil extraction for various raw materials. The summary of this paper included information on different plant materials, the most suitable extraction method with operating conditions, advantages, and disadvantages of extraction methods, etc.

Microwave Hydrodiffusion and Gravity Extraction of Vitamin C and Antioxidant Compounds from Rosehips (Rosa canina L.).

Rosehips, Rosa canina L. (Rosaceae family), have been used for a long time for their beneficial effects on health, and they are largely exploited in the food and nutraceutical supplement sectors. The aim of this work was to apply and optimize for the first time the microwave hydrodiffusion and gravity (MHG) extraction of rosehips, as a novel application of solvent-free microwave extraction, previously conducted in a similar way only on mulberry, strawberry, and onion. The optimization was performed through a central composite design (CCD) by evaluating the effect of the experimental parameters on the yield; total polyphenol, flavonoid, and anthocyanin contents; radical scavenging activity; and content of vitamin C in the obtained extracts. As a result, the water moistening pretreatment was clearly revealed to possess a pivotal role in the quality of the rosehip extracts. Among the evaluated responses, the yield, the anthocyanin content, and the antioxidant activity were well described by the statistical model. Notably, the optimized MHG extract was compared with the ones obtained by conventional solvent extraction showing higher amounts of vitamin C, polyphenols, flavonoids, and anthocyanins, while the traditional extracts performed better in terms of yield. In conclusion, MHG represents a promising alternative to standard extraction methods for obtaining rosehip extracts rich in vitamin C and antioxidant compounds. In this respect, the results of our research support the employment of MHG on an industrial level for the production of rosehip-based food supplements enriched in vitamin C.

COMPARISON PROCESS OF SOLVENT-FREE MICROWAVE EXTRACTION AND MICROWAVE HYDRO-DISTILLATION METHODS IN ESSENTIAL OIL PRODUCTION FROM CABBAGE ROSES FLOWER (Rose × centifolia)

Indonesia has many diverse natural resources that still cannot be utilized optimally such as the extraction of essential oil from Cabbage Roses flowers (Rose × centifolia). This study compares the extraction amendments, extraction time, and essential oil composition of fresh rose flowers obtained by the Solvent-Free Microwave Extraction (SFME) method to those obtained using the Microwave Hydro-Distillation (MHD) extraction method. Optimum conditions using the same amount of raw material in this study for the MHD method optimum conditions of operation: time of 90 minutes; the ratio of 1 g/mL; the power of 450 W, obtained a yield of 0.152% and SFME method optimum conditions of operation: time of 90 minutes, ratio 0.2 g/mL; power 450 W, obtained a yield of 0.358%. Electricity consumption to obtain 1 g of rose essential oil extracted using the MHD method is 4.087 kWh, while for the SFME method, it is 1.073 kWh. So it can also be said that the MHD method requires electricity consumption which is 3.8 times higher when compared to the SFME method.

Solvent-free microwave extraction of essential oil and hydrosol from fresh leaves of Cinnamomum burmannii (Nees et T. Nees) Blume after screw extrusion treatment and evaluation of pancreatic lipase inhibitory activities in vitro compared to its main components

One of the most significant sources of commercial camphor oil is the essential oil of Cinnamomum burmannii (Nees et T. Nees) Blume leaves, which has been manufactured using a variety of distillation techniques, including hydrodistillation and microwave-assisted hydrodistillation. In this study, we employed solvent-free microwave extraction (SFME) to recover hydrosol and essential oil from fresh C. burmannii leaves that had undergone screw extrusion. An optimum yield of 12.35 ± 0.62 mL/kg DW of essential oil was obtained by optimizing the major SFME contributing parameters using a face-centered central composite design (FCCCD). By using SFME, the influence of microwave irradiation power on the yield and quality of the essential oil of fresh leaves of C. burmannii was examined. With the aid of first- and second-order kinetic equations, SFME was contrasted with hydrodistillation and dry distillation. A total of 32 components were detected in the essential oil, and 22 components were detected in the hydrosol obtained by SFME under the optimized conditions. The main components of the essential oil were 1,8-cineole (21.67%), borneol (17.37%) and α-terpineol (7.45%), in descending order, and the main components of the hydrosol were trans-2-hydroxycinnamic acid (21.45%), borneol (22.07%), 1,8-cineole (13.65%) and α-terpineol (11.93%). 1,8-Cineole and borneol were the two components with the highest influence on hierarchical clustering, according to principal component analysis and heatmap analysis. Moreover, box-whisker plots were used to determine and compare the inhibitory activities of the essential oil and its three primary constituents against pancreatic lipase. The outcomes demonstrated that 1,8-cineole played a critical role in the essential oil's ability to inhibit pancreatic lipase, and they also demonstrated a positive correlation between the concentration and the amount of inhibition activity.

Variation in Yield, Chemical Composition and Biological Activities of Essential Oil of Three Curcuma Species: A Comparative Evaluation of Hydrodistillation and Solvent-Free Microwave Extraction Methods.

The essential oils of three medicinally important Curcuma species (Curcuma alismatifolia, Curcuma aromatica and Curcuma xanthorrhiza) were extracted using conventional hydro-distillation (HD) and solvent free microwave extraction (SFME) methods. The volatile compounds from the rhizome essential oils were subsequently analysed by GC-MS. The isolation of essential oils of each species was carried out following the six principles of green extraction and comparison was made between their chemical composition, antioxidant, anti-tyrosinase and anticancer activities. SFME was found to be more efficient than HD in terms of energy savings, extraction time, oil yield, water consumption and waste production. Though the major compounds of essential oils of both the species were qualitatively similar, there was a significant difference in terms of quantity. The essential oils extracted through HD and SFME methods were dominated by hydrocarbon and oxygenated compounds, respectively. The essential oils of all Curcuma species exhibited strong antioxidant activity, where SFME was significantly better than HD with lower IC50 values. The anti-tyrosinase and anticancer properties of SFME-extracted oils were relatively better than that of HD. Further, among the three Curcuma species, C. alismatifolia essential oil showed the highest rates of inhibition in DPPH and ABTS assay, significantly reduced the tyrosinase activity and exhibited significant selective cytotoxicity against MCF7 and PC3 cells. The current results suggested that the SFME method, being advanced, green and fast, could be a better alternative for production of essential oils with better antioxidant, anti-tyrosinase and anticancer activities for application in food, health and cosmetic industries.

Assessing the Larvicidal Properties of Endemic Campeche, Mexico Plant Piper cordoncillo var. apazoteanum (Piperaceae) against Aedes aegypti (Diptera: Culicidae) Mosquitoes

The research aims to investigate the mortality effect of essential oil from Piper cordoncillo var. apazoteanum, an endemic plant from Campeche, Mexico, on early second-instar Aedes aegypti larvae; it also aims to identify the volatile compounds present in the fresh leaves of the plant. To test the effectiveness of the essential oil, we followed World Health Organization Standard Procedures. Larvae were observed for 17 consecutive days after treatment to determine the mortality and growth-inhibitory effect exerted by the essential oil. The results showed that the essential oil was effective in controlling mosquito populations. At a concentration of 800 ppm, the oil achieved an effectiveness rate of 70.00 ± 8.16% after 24 h, increasing to 100.00 ± 0.01% mortality after 72 h. With a concentration of 400 ppm, the effectiveness was 98.33 ± 0.17% by the end of the experiment. Furthermore, the obtained results demonstrated that the LC50 value was 61.84 ± 6.79 ppm, while the LC90 value was 167.20 ± 11.49 ppm. Essential oil concentrations inhibited the growth of immature insect stages, with concentrations between 800-100 ppm demonstrating very high inhibitory activity, and the lowest concentration of 50 ppm showing high inhibitory activity. The study also identified 24 chemical compounds representing 86.71% of the volatile compound composition of the fresh leaves of P. cordoncillo; the most abundant compounds were Safrole, Caryophyllene oxide, E-Nerolidol, and Calarene epoxide. The method used to extract the volatile compounds, solvent-free microwave extraction (SFME), is a promising alternative to traditional methods that avoids the use of potentially harmful solvents, making it more ecologically friendly and potentially safer for professionals handling the extracted compounds. Overall, the study demonstrates the potential of P. cordoncillo essential oil as an effective means of controlling mosquito populations, and provides valuable information on the chemical composition of the plant.Moreover, our study is the first to report on the biological activity and chemical composition of P. cordoncillo worldwide.

Extraction of Cinnamomum longepaniculatum deciduous leaves essential oil using solvent-free microwave extraction: Process optimization and quality evaluation

The optimal process conditions for solvent-free microwave extraction (SFME) of essential oils from Cinnamomum longepaniculatum deciduous leaves after moisture conditioning were established by response surface methodology (RSM). A Box-Behnken design (BBD) was applied to evaluate the effects of three independent variables: moisture content (A: 54%–74%), microwave power (B: 300–500 ​W) and microwave time (C: 20–40 ​min), on the extraction yield of essential oil. The compounds of the essential oils obtained by SFME, hydro-distillation and microwave-assisted hydro-distillation (MADE) were identified by gas chromatography-mass spectrometry (GC-MS), and the total lipids of C. longepaniculatum fresh leaves and deciduous leaves were analyzed. The correlation analysis of the response regression model indicated that quadratic polynomial model could be employed to optimize the extraction of essential oil. The optimal extraction condition was A: 58%, B: 400 ​W and C: 28 ​min. In the optimal condition, the maximum extraction yield was 4.475 mL/100 ​g dw and higher than that by MADE. The main compound of the essential oil was eucalyptol (63.54%), and total oxygenated compounds was 78.95%, mainly caused by SFME and the metabolism of endophytic bacteria with decreasing content of phospholipids and fatty acids. Analysis of variance under the extraction condition illustrated high fitness of the model and the success of RSM for optimizing and reflecting the expected process condition. SFME combined with moisture regulation was an effective method for extracting essential oil from C. longepaniculatum deciduous leaves.

Yield, chemical composition, and antioxidant activity of essential oil obtained from Ferula persica oleo-gum-resin: Effect of the originated region, type of oleo-gum-resin, and extraction method

In the present study, we investigated the effect of extraction methods (hydro-distillation, microwave-assisted hydro-distillation, and solvent-free microwave extraction), oleo-gum-resin types (Kokh and Shir), and regions (Sepidan and Darb-e-Behesht) on yield, composition and antioxidant activity of essential oils obtained from oleo-gum-resin of Ferula persica. The results showed that oleo-gum-resins originating from Darb-e-Behesht produced more essential oil than oleo-gum-resins of Sepidan using each of the extraction methods. Each of the extraction methods isolated more essential oil from Kokh samples as compared with Shir. The highest essential oil was achieved by the solvent-free microwave extraction method from Kokh samples. A total of 51 compounds were identified in essential oil samples. Monoterpene hydrocarbons and sulfur compounds were dominant in all essential oils. The main compounds of essential oil in the samples were β-pinene, α-pinene, (E)− 1-Propenyl sec-butyl disulfide, and (Z)− 1-Propenyl sec-butyl disulfide. The antioxidant activity of the essential oils was affected by the region and type of oleo-gum-resin. The essential oils showed less antioxidant activity than butylated hydroxyanisole. The research suggests that the area of oleo-gum-resin collection, type of oleo-gum-resin collected, and essential oil extraction method should be selected and optimized based on the intended purpose and the desired active ingredients. Also, the results show that microwave-assisted hydro-distillation and solvent-free microwave extraction methods can be introduced as quick and suitable alternative methods for extracting essential oils from oleo-gum-resins of F.persica.

Solvent-Free Microwave Extraction of Essential Oils from Litsea cubeba (Lour.) Pers. at Different Harvesting Times and Their Skin-Whitening Cosmetic Potential.

Litsea cubeba fruit, which has the highest content of essential oils in the plant, is an important woody oil plant resource. In this study, the influence of the solvent-free microwave extraction (SFME) and hydrodistillation (HD) techniques on the extraction of L. cubeba fruit essential oils was investigated in terms of yield, kinetics, and chemical composition, where the former conditions were optimized by the response surface design. The maximal essential oil yield was obtained under the optimal SFME process conditions (442 W and 24 min), where the irradiation time was the most important variable (p < 0.0001). Regardless of the extraction method used, the influence of harvesting time on L. cubeba fruit essential oils were quantitatively and qualitatively analyzed afterwards, where the SFME essential oil from July showed its superiority over the others regarding its higher extraction yield and better bioactivities. Compared with the HD method, the SFME approach could significantly enhance the yield of essential oils extracted from June to August by nearly 47% with the advantages of saving energy and low environmental impact. Interestingly, the SFME method could selectively extract monoterpene hydrocarbons such as D-limonene with relation to different compositions and bioactivities. Moreover, SFME essential oil showed a better inhibitory effect on tyrosinase and melanogenesis, indicating its skin-whitening potential as a new promising natural cosmetic ingredient.

PHYTOCHEMICALS, ANTIOXIDANT AND ANTIMICROBIAL ACTIVITY OF CENTELLA ASIATICA EXTRACTED BY SOLVENT-FREE MICROWAVE EXTRACTION

Solvent-free microwave extraction (SFME) is a green extraction method that requires no solvent and has a short extraction time. This study extracted Centella asiatica using SFME and analysed the extract for its phytoconstituents, phenolic content, antioxidant, and antimicrobial activity. Extraction of 20 g fresh C. asiatica by SFME was carried out for 15 min at 300 W, under vacuum and with stirring. Analysis by gas chromatography-mass spectroscopy (GC-MS) demonstrated that the extract contained phytonutrients such as flavonoids, polyphenol, tannins, and volatile oils. The extract from SFME also produced an IC50 of 0.06 mg/ml and 10.75±0.61 mg GAE/g dry weight of TPC. Using the disc diffusion method, the extract of C. asiatica also exhibited antimicrobial activity against Escherichia coli, Bacillus subtilis, Staphylococcus aureus, Enterobacter sp., Aspergillus niger, Aspergillus flavus, Penicillium chrysogenum and Aspergillus japonicus. This study showed that the C. asiatica extract from SFME retained the antioxidant and antimicrobial properties but in a shorter extraction time and without any solvent. As a result, using green extraction to extract this plant can help to preserve its nutritional content and valuable compounds, which is essential when formulating pharmaceutical, food, and cosmetic products.

Optimization of solvent-free microwave extraction of essential oil from the fresh peel of Citrus medica L. var. arcodactylis Swingle by response surface methodology, chemical composition and activity characterization

Citrus medica L. var. sarcodactylis Swingle (finger citron) is a traditional Chinese herb and considered as a functional vegetable. In this study, a green extraction method of solvent-free microwave (SFME) was used to isolate finger citron essential oil (FEO). Under the optimal extraction process parameters, the FEO yield (1.65% ± 0.05%) from SFME was 27.91% higher than that from hydro distillation (HD) (1.29% ± 0.03%), and its total phenolic and total flavonoid content were higher than that HD. The GC–MS results further showed the contents of some active components in FEO from SFME method increased significantly, including Citronellol (+4.8%), Geraniol (+3.95%), trans-Citral (+3.92%), cis-Citral (+2.06%), α-Terpineol (+1.09%), Hexadecanoic acid (+1.02%) and Linoleic acid (+0.9%). The antibacterial activities of FEOs were comprehensively evaluated by 6-axe cobweb charts. The experimental results of antioxidant, acetylcholinesterase inhibitory and antimicrobial activity showed that FEO from SFME method were significantly better than that from HD method. No solvents were used in the extraction of essential oils by the SFME method, which was in full compliance with the current requirements of green chemistry. This research will provide a new process for the extraction of essential oil from the fresh peel of finger citron and contribute to its industry development.

Optimization of Essential Oil Extraction of Beluntas (Pluchea Indica L.) Leaves by Using Solvent-Free Microwave Extraction

Beluntas (Pluchea Indica L.) which commonly used as astringent and antipyretic has a high potential for the feedstock of essential oil production. The objective of this work is to optimize solvent-free microwave extraction (SFME) of Beluntas leaves by using response surface methodology (RSM). Box-Behnken Design with the variations of extraction time (60-120 min), feed/distiller ratio (0.06-0.1 g/ml), and heating power (150-450 W) was utilized to optimize essential oil yield. The feed/distiller ratio factor had the highest significant effect on the essential oil yield (P<0.05). Essential oil yield increased as the increase of oil heating power and time extraction, and vice versa. On the other hand, the increase in the feed/distiller ratio gave a negative impact on the essential oil yield. The maximum essential oil yield using SFME method of 0.2728 b/b% was obtained for the optimized condition of extraction time of 90 min, microwave heating power of 450 W, and feed/distiller ratio of 0.06.

Comparison of different methods for the extraction of essential oil from the rhizome part of Kaempferia galanga linn

Kaempferia galanga linn (KGL) is a well-known condiment in Southeast Asia, consisting of huge advantages for health sustainability. This research aims to compare the essential oils (EOs) yield of the KGL rhizome utilising modern technologies – solvent-free microwave extraction (SFME) and microwave-assisted extraction (MAE) to the traditional method of hydrodistillation (HD). The influence of process parameters on the oil yield is determined and the composition of the extracts is characterised using Gas Chromatography-Mass Spectrometer (GCMS). The SFME has been demonstrated as the most excellent method in producing substantially high yield in a shorter time (40 min, 2.54 %) in comparison to the MAE (40 min, 1.03%) and HD (3 h, 0.14%). Ethyl p-methoxycinnamate from the class of cinnamic acid ester appears as the main volatile constituent with a percent content of 11.6%, 10%, and 13.4% obtained by SFME, MAE, and HD, respectively. The SEM analysis of the KGL reveals that microwave technology caused a significant plant cell wall rupture, thus promoting faster oil extraction than the traditional extraction approach. This study demonstrates that SFME is a promising alternative to producing essential oil as natural products without solvent, safer for pharmaceutical and food industries.

Sustainable Extraction, Chemical Profile, Cytotoxic and Antileishmanial Activities In-Vitro of Some Citrus Species Leaves Essential Oils

Anti-leishmanial drugs extracted from natural sources have not been sufficiently explored in the literature. Until now, leishmaniasis treatments have been limited to synthetic and expensive drugs. This study investigated, for the first time, the anti-leishmanial efficacy of essential oils (EOs) from the leaves of Citrus species (C. sinensis, C. limon, and C. clementina). Essential oils were extracted from three species by solvent free microwave extraction (SFME); in addition, lemon oil was also isolated by hydro-distillation (HD). These were investigated using gas chromatography coupled with mass spectrometry (GC–MS) and evaluated against Leishmania species, namely Leishmania major and Leishmania infantum, using a mitochondrial tetrazolium test (MTT) assay. The chemical compositions of Citrus limon EOs obtained by HD and SFME showed some differences. The identified peaks of C. limon (SFME) represented 93.96%, where linalool was the major peak (44.21%), followed by sabinene (14.22%) and ocimene (6.09%). While the hydro-distilled oil of C. limon contained geranial (30.08%), limonene (27.09%), and neral (22.87%) in the identified peaks (96.67%). The identified components of C. clementina leaves oil (68.54%) showed twenty-six compounds, where the predominant compound was geranial (42.40%), followed by neral (26.79%) and limonene (14.48%). However, 89.82% C. sinensis oil was identified, where the major peaks were for neral (27.52%), linalool (25.83%), and geranial (23.44%). HD oil of lemon showed the highest activity against L. major, with moderate toxicity on murine macrophage (RAW 264.7) cells, and possessed the best selectivity index on both Leishmanial species (SI: 3.68; 6.38), followed by C. clementina oil and C. limon using SFME (0.9 ± 0.29, 1.03 ± 0.27, and 1.13 ± 0.3), respectively. C. clementina oil induced the greatest activity on Leishmania infantum, followed by HD lemon and SFME lemon oils (0.32 ± 0.18, 0.52 ± 0.15, and 0.57 ± 0.09, respectively) when compared to Amphotericin B (0.80 ± 0.18 and 0.23 ± 0.13) as a positive control, on both species, respectively. Our study suggests a potent anti-leishmanial activity of lemon oil (HD) on L. major, followed by C. clementina. With the same potency on L. infantum shown by C. clementina oil, followed by HD lemon oil. This effect could be attributed to the major compounds of limonene, citral, and neral, as well as the synergistic effect of other different compounds. These observations could be a starting point for the building of new anti-leishmanial drugs from natural origins, and which combine different EOs containing Citrus cultivars.

Reconfiguring extraction of phenolics & flavonoids through a solvent-free gravity assisted model for the complete recovery of target analytes from moringa leaves: A complete overhauling attempt in the field of botanical extraction

In this study solvent-free microwave extraction has been emphasized as a green tool kit for complete recovery of phenolic and flavonoid principles from fresh moringa leaves (80% w/w moisture content). Extraction comprised of exposure of fresh moringa leaves to different microwave power levels (170 W, 255 W, 340 W, 425 W, 510 W, and 595 W) in short cycles of 5 min each till the last drop of the extract was obtained. A three-stage performance evaluation policy (total phenolics/flavonoid content, HPTLC profiling, and antioxidant activity) was adopted for performance evaluation. The highest TPC (67.3 mg GAE/gm of dried extract) and TFC (117.78 mg QE/gm of dried extract) value was obtained when operated at 510 W microwave power level which lasted for 5 cycles of 5 min each. The maximum content of chlorogenic acid (776.35 μg/gm of dried extract), gallic acid (56.23 μg/gm of dried extract), quercetin (17.02 μg/gm of dried extract) and p-coumaric acid (60.33 μg/gm of dried extract) was found from the same operating condition as well. The highest % scavenging activity of 69.5% was also reported for the extract obtained at 510 W power level. Extraction was found to obtain its peak at the 3rd cycle of 510 W power level. Results were in sync with SEM and chemomicroscopic studies. Such technology not only provides automation but also gives us the comfort of “push a button and walk away”, the need of the hour.