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Phenolic compounds are essential for growth, pigmentation, resistance to pathogens, reproduction, and among others. This study focused on the optimization of microwave-assisted extraction process variables, i.e., solvent/sample ratio (X1), irradiation time (X2) and microwave power (X3), based on the yields of total phenolic content (TPC) and total flavonoid content (TFC) from Ocimum gratissimum leaf using Box Behnken Design. Furthermore, the chemical compounds in the extract under optimized MAE conditions were identified using LC–ESI–MS/MS analysis; its antioxidant and antibacterial properties were evaluated as well, and optimal MAE conditions, i.e., X1 = 10:1 mL/g, X2 = 3 min and X3 = 553 W, were obtained with TPC and TFC yields of 184.99 ± 3.05 (mg GAE/g extract) and 68.78 ± 2.07 (mg QE/g extract), respectively. The results indicated that the leaf extract of O. gratissimum possesses antioxidant and antibacterial properties. Aside from these, the LC–ESI–MS/MS analysis provided tentative identification of 131 phenolic and other phytochemical compounds in the leaf extract at optimized conditions. The extract showed higher inhibitory activities against all the considered bacteria organisms (at least the concentration of 15 mg/mL). Thus, O. gratissimum leaf can be employed as an industrial crop with potential usage in the nutraceutical and food products.

Carica papaya is a perennial large herbaceous plant known for diverse biological activities. Different parts of this plant such as seeds, leaves, fruits, peels, roots, and stems have been previously reported to possess nutritional and medicinal values. This plant possesses a nutritional value that is rich in vitamins and natural minerals but low in calories. Moreover, every part of this plant had been used in treating different type of diseases which include wound dressing, antibacterial, anthelminthic effects, traditionally used to control birth, and several other activities. These were born out of the in vitro and in vivo studies conducted on the extracts from parts of C. papaya. Furthermore, the occurrences of different kinds of phytochemicals in the extracts might have been responsible for its diverse pharmacological properties. Thus, this article comprehensively outlines and discusses nutritional values, phytochemistry and pharmacological activities of C. papaya.

Since the World Health Organization has suggested the exploration of natural products for cancer management owing to the side effects of chemotherapy and irradiation on humans and breast cancer accounts for the highest number of cancer related deaths globally, this study has examined antiproliferative effects of the aqueous and methanol extracts of Hypsizygus tessellatus (brown and white var.) and Flammulina velutipes caps against two breast cancer cell lines. The antioxidant and antiproliferative activities of these mushroom extracts were evaluated in vitro using chemical-based (for antioxidant activity) and cell (for antiproliferative activity) approaches. Furthermore, the phytochemical composition of the mushroom extracts were identified using mass spectroscopy (UPLC-QTOF/MS). The obtained results showed aqueous extracts of F. velutipes (Enoki) and white H. tessellatus (Bunapi shimeji) caps to possess higher antiodixant activities against DPPH (IC50 = 0.202 and 0.573 mg/mL, respectively), and H2O2 (IC50 = 0.622 and 0.745 mg/mL, respectively) compared tothe methanol extracts. Aqueous extracts of the mushrooms also showed better ferric reducing antioxidant power (FRAP) values against ferric ions compared to the methanol extracts. Finally, the mushroom extracts showed good antiproliferative activities against human breast cancer cell lines. These findings suggest the presence of phytochemicals with antiproliferative and antioxidant acrtivities in the mushroom extracts studied.

Vernonia amygdalina leaves are mostly consumed in Asia and Africa, due to its potential as a good source of antioxidants. In this study, a two-level factorial design was used to evaluate the significant extraction parameters in achieving higher recovery yield of extract, total phenolic content, total flavonoid content, and antioxidants from Vernonia amygdalina leaf. Microwave-assisted extraction technique was employed using aqueous ethanol. The independent parameters were irradiation time (1–5 min), microwave power level (500–700 W), temperature (60–80 °C), feed-to-solvent ratio (1:8–1:12 g/ml), and ethanol concentration (40–80%). Amongst the examined parameters, ethanol concentration, irradiation time, microwave power level, and feed-to-solvent ratio were significant (p

The bioactive compounds in Vernonia amygdalina leaf were extracted using ethanol through Soxhlet and microwave-assisted extraction (MAE) techniques. The phytochemical analysis was carried out on the ethanolic extracts using the standard techniques. This analysis revealed the presence of flavonoids, alkaloids, steroids, terpenoids, glycosides, tannins, phenols, saponins, and the absence of anthraquinones. Furthermore, gas chromatography-mass spectroscopy (GC-MS) analysis results revealed the presence of more phytochemicals in the extract obtained through MAE compared to Soxhlet extraction technique, whereby phytol was present in a higher percentage. Fourier transform infrared spectroscopy analysis confirmed the presence of phytochemicals in the extracts. Moreover, the IC50 values of the extracts antioxidant activities were evaluated using DPPH and ABTS assays. There exists a clear correlation between total phenolic content, total flavonoid content and antioxidant activity of the extracts. Therefore, this study suggested that higher phenolic compounds responsible for natural antioxidant could be obtained from V. amygdalina leaf using the microwave-assisted extraction technique.

The extracts from Vernonia amygdalina leaves dried using different modes of drying were examined for their antioxidant activities. The component identification was carried out on extract with the highest antioxidant property using GC–MS analysis. Using DPPH, ABTS+ and H2O2 radical scavenging assays, the shade, the sun, oven at 40, 50, and 60 °C dried sample extracts were screened. The obtained scavenging activities were in the order: shade drying > sun drying > oven drying at 40 °C > oven drying at 50 °C > oven drying at 60 °C. The extract from shade-dried sample exhibited the highest activity by scavenging 63.21–92.25% of DPPH, 75.32–93.15% of ABTS+, and 82.53–95.78% of H2O2 radicals, which were higher than those of ascorbic and gallic acid scavenging activities. In addition, the effects of drying methods and extract concentrations on the antioxidant activity of V. amygdalina leaf were significant (p < 0.05). A total number of 11 major compounds were identified from the shade-dried extract viz: phytol (43.69%), (z,z,z)-methyl ester-9,12,15-octadecatrienoic acid (17.60%), 2-methyl-3-hexanol (6.83%), ethyl ester-9,12-octadecadienoic acid (6.07%), ethyl ester linoleic acid (5.19%), ethyl ester hexadecanoic acid (5.06), heneicosane (4.15%), heptacosane (3.25%), and others are less than 3%. Therefore, it can be deduced that an increase in drying temperature may deteriorate the antioxidant activity of Vernonia amygdalina leaf.

Black and white peppers are important oil bearing commodity crop in tropical areas. They are highly beneficial in food industries and herbal medicine, due to their amazing aroma and therapeutic activities. In this study, heat reflux technique was employed to extract medicinal oleoresin from the two peppercorns. For this purpose, various extraction parameters were considered viz: extraction time, particle size and feed-solvent ratio. These extraction parameters were employed to optimize the extraction yield and absorbed energy via Taguchi methodology. The established optimal condition values of the yield and absorbed energy from the parametric study were 13.22 mg/g and 285.60 J/min, respectively in black pepper heat refluxation. Moreover, in white pepper refluxation, the extraction yield and absorbed energy were 14.04 mg/g and 264.82 J/min, respectively. Artificial neural network (ANN) was used for prediction purposes. This was achieved by comparing two algorithms, transfer functions and neurons. A good training and better prediction of the experimental data were observed using the Levenberg Marquardt (LM) feed forward backpropagation algorithm with log sigmoid transfer function as hidden layer and 3-4-5-1 as model topology. Furthermore, a total of 19 and 25 bioactive compounds were identified in black and white pepper extracts, respectively. The results from the Scanning Electron Spectrometry (SEM) showed a remarkable morphological changes during the heat refluxation process.

Fenugreek (Trigonella-Foenum Graecum) is known as one of the traditional and most promising medicinal herbs belongs to the leguminous family. The seeds of fenugreek have been extensively studied for the treatment of inflammation, cancer and diabetes. In this study, fenugreek seed oil was extracted and evaluated for its chemical compositions and bonding through gas chromatography coupled to mass spectrometry (GC-MS) and Fourier transform infrared spectroscopy (FT-IR) analysis, respectively. The antioxidant activity against 2,2-diphenyl-picrylhydrazyl (DPPH) and 2,2′-Azino-bis-3-ethylbenzothiazoline-6-sulfonic acid (ABTS+•) radicals, total phenolic content (TPC) and total flavonoid content (TFC) of the oil were also studied. The capacity of antioxidants detected by ABTS was stronger than that by DPPH. A total number of 23 chemical compounds were detected and identified in fenugreek seed oil comprising of 99% of the total oil through GC-MS analysis. The major compounds of the extracted oil were linoleic acid (54.13%), palmitic acid (16.21%), pinene (4.56%), 4-Pentyl-1-(4-propylcyclohexyl)-1-cyclohexene (3.87%) and linoleic acid methyl ester (3.19%). FTIR analysis confirmed the presence of carboxyl group in the oil which were more dominated by unsaturated essential fatty acids. Moreover, the oil of fenugreek seed indicated a strong antioxidant radical scavenging activity against both DPPH and ABTS assays with an IC50 of 172.6 ± 3.1 and 161.3 ± 2.21, respectively. The TPC and TFC of the oil were 38.97 ± 0.34 mg GAE/g. oil and 14.417 ± 0.23 mg QE/g.oil. Thus, this study suggests that the fenugreek seed oil could be used for pharmaceutical purposes. Keywords: Fenugreek seed oil, Gas chromatography-mass spectrometry, Unsaturated essential fatty acid, Antioxidant, Total phenolic content, DPPH, ABTS

In this study, the oven drying behaviour, as well as changes in the morphological appearance of Vernonia amygdalina leaves before and after drying were investigated. The drying experiments were conducted using a universal oven. Vernonia amygdalina leaves were dried at 40, 50 and 60 °C air temperatures. During the drying processes, the air flow rate was held at 1 m/s2 and the samples spread on the drying trays were placed parallel to the direction of air flow. The obtained data were fitted to eleven different mathematical drying models. Four statistical tools, viz, correlation coefficient, mean bias error, sum of the square error, and reduced chi-square were used to analyse the fittings. Amongst the considered drying models, Midilli-Kucuk drying model showed the best fitting in describing the drying behaviour of Vernonia amygdalina leaves. In addition, the effective diffusivities for the three air temperatures ranged from 4.55 × 10−12 to 5.48 × 10−12 m2/s with the activation energy of 8.048 kJ/mol. Moreover, to evaluate the effect of drying conditions on the morphological changes of Vernonia amygdalina leaves, fresh and dried leaves under different conditions were compared. Thus, drying conditions had effects on microstructure of Vernonia amygdalina leaves. Keywords: Drying, Mathematical models, Morphology, Vernonia amygdalina

Aloe vera is a perennial ethno-medicinal potential plant with a xerophytic characteristic, but not a cactus. It has a famous history owing to its phytopharmaceutical properties and this had made it useful in the pharmaceutical, cosmetic and food industries. Studies had shown the positive effects of its extract against bacteria, organisms. The phytochemical properties of A. vera have fungi, virus and parasitic been exploited for various economic and commercial purposes. This review contributes literature on the bioactive potential composition, processing and the pharmaceutical potential uses, an adverse side-effect that might spring up in case of over dosage and important safety precautions are summarized. More scientific innovations and developments in the aspect of analytical chemistry are on the way to provide more acceptable, purified chemical characterization of A. vera using sophisticated laboratory equipment and machines.

Microwave-assisted extraction (MAE) of phenolic compounds from Chromolaena odorata leaves was investigated using one-factor-at-a-time (OFAT) and two-level factorial design. The MAE parameters studied were irradiation time (A: 1–5 min); microwave power level (B: 400-800 W); extraction temperature (C: 60–80 °C); solvent/feed ratio (D: 8:1–14:1 mL/g); and ethanol concentration (E: 20–60% v/v). The optima yields of TPC and TFC were 56.13 mg GAE/g d.w. and 44.78 mg QE/g d.w., respectively were achieved from MAE of C. odorata leaf at irradiation time of 2 min, microwave power of 600 W, temperature of 60 °C, solvent:feed ratio of 10:1 mL/g, and ethanol concentration of 40% v/v through one-factor-at-time (OFAT) experimental trials. The results obtained from a two-level factorial design experiments reflected that only ethanol concentration (20–60% v/v), irradiation time (1–5 min) and microwave power level (400–800 W) had significant effects on the yields of total phenolic content (TPC) and total flavonoid content (TFC) from C. odorata leaves (p < 0.05). However, temperature and solvent/feed ratio was not significant. In addition, the interactions AB (irradiation time and microwave power) and AE (irradiation time and ethanol concentration) contributed greatly to the recovery yields.

Carica papaya is a well-known plant with diverse importance to human beings. The efficacy of microwave-assisted extraction (MAE) in the recovery of phenolic compounds from C. papaya leaf was investigated in this study. The MAE process variables were optimized using response surface method; at the optimized conditions, the embedded phenolic compounds in the extract were identified through LC-QTOF-MS analysis. The results showed that the best MAE conditions were: time of irradiation at 3 min; microwave power of 420 W; feed-to-solvent ratio of 1:12 g/mL; and solvent concentration of 56% ethanol/water to achieve 102.59 mg GAE/g d.w. of total phenolic content (TPC). At these conditions, an aggregate of 72 phenolic compounds was tentatively identified. These results infer that MAE as a technique can recover phenolic compounds from C. papaya leaf. Hence, the identified compounds can further be quantified with their respective pharmacological properties in future studies.

The free radicals are reactive molecules that emanate during oxidation; this can then stimulate a chain reaction that can cause cellular damage. A lot of studies had affirmed the implications of free radicals mostly the reactive oxygen species in generating over a hundred degenerative diseases in the human being; these include cancer, acquired immunodeficiency syndrome (AIDS), diabetes, central nervous system injury, arthritis, gastritis, atherosclerosis, reperfusion, and ischemia injury of different tissues. Scientific studies have postulated that the bioactive compounds mainly from natural products can protect the body system from free radicals. Thus, this chapter focuses on the antioxidant potential of Vernonia amygdalina and its toxicology.

The high death rate associated with cancer has fuelled the search for complementary cancer treatment methods in recent times. Among the leading alternative methods is natural products which have attracted much attention due to their high body tolerance. In this study, the caps of Flammulina velutipes (commonly called Enoki), an edible mushroom, were extracted with different solvents and characterized for in vitro antioxidant and anticancer activities. The anticancer activity of the extract was studied against breast cancer cells (MCF-7 and MDA-MD-231) and normal or Vero breast cells (MCF-10a). The radical scavenging, metal reducing power, and anticancer properties of the extracts were investigated via in vitro chemical and cell-based methods. Furthermore, a phytochemical profiling process was performed on the extract fraction with the highest level of biological activities using Liquid chromatography-mass spectrometry coupled with quadrupole time of flight (LC-MS-QTof). The results showed acetone fraction of Enoki caps to exhibit more radical scavenging activity against 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radicals (IC50 = 0.840 mg/mL) and hydrogen peroxide (H2O2) radicals (IC50 = 0.890 mg/mL) compared to the ethyl acetate fraction (IC50 = 0.97 mg/mL against DPPH and 1.180 mg/mL against H2O2). Additionally, acetone fraction showed a better metal reducing property in a concentration-dependent manner. The in vitro cytotoxicity study showed a preferential level of toxicity of the acetone extract to the studied cancer cell lines compared to the Vero cells. This extract showed more cytotoxicity against MCF-7 (IC50 value ranged from 17.7 µg/mL to 38.36 µg/mL) and MDA-MB-231 (IC50 value ranged from 114.5 µg/mL to 184.2 µg/mL) compared to MCF-10a (>250 µg/mL). These findings present F. velutipes caps as a potential natural source of antioxidant and anticancer agents. Keywords: Anticancer, Antioxidant, Breast cancer, F. velutipes, Phytochemicals

Black pepper is a functional plant with nutritional and medicinal benefits. Piperine being the major bioactive compound in black pepper has been applied for the treatment of many free radical-related diseases. This study determined a combination of operating parameters that optimize the microwave extraction of the piperine oil. The effect of irradiation time, microwave power level, feed particle size and feed-solvent ratio on piperine content and absorbed microwave energy were tested using a three-level L9-Taguchi parametric design. The results obtained placed the optimum extraction condition at 90 min of irradiation time, 350 W of microwave power, 0.1 mm of particle size and 1:12 of feed-solvent ratio. Under this optimal condition the optimal piperine oil and absorbed microwave energy of 5.64 w/w and 84.17 J/min were obtained, respectively. The optimal conditions can therefore be employed to design extraction process with higher efficiency and productivity. Keywords: Black pepper, Piperine, Microwave reflux extraction, Taguchi optimization, Signal-to-noise ratio

The tentative identification of bioactive compounds in the extract of Vernonia amygdalina leaf was carried out using positive ionization of Liquid chromatography-mass spectrometry quadrupole time of flight (LC-Q-TOF/MS). The positive ionization is associated with the presence of saponins, flavonoids, alkaloids, terpenoids, and glycosides. Tentative assignments of the secondary metabolites were performed by comparing the MS fragmentation patterns with Waters® UNIFY library which allows positive identification of the compounds based on the spectral match. All the metabolites compounds were estimated and presented in a BPI (Base peak intensity) plot. These data are the unpublished supplementary materials related to “Ethanolic extraction of bioactive compounds from V. amygdalina leaf using response surface methodology as an optimization tool” (Alara et al., 2018).

Cancer management is associated with serious side-effects due to the harmful nature of radiation and chemotherapy on the body cells. These side-effects have necessitated the need for diversifying the alternative or complementary sources of cancer therapy. Natural products have been on the front line as alternative sources of anticancer agents and have attracted much attention in recent times. In this study, the anticancer activity of Hypsizygus tessellatus (white var.) caps (also known as Bunapi shimeji) extracted with acetone and ethyl acetate was evaluated in vitro against MDA-MB-231 and MCF-7 (breast cancer cell lines) and MCF-10a (Vero or normal breast cells). Likewise, the free radical scavenging and metal reducing activities of the extract were evaluated through in vitro chemical-based methods. Furthermore, the phytochemical compositions of the extracts were determined through LC–MS-QTOF-assisted mass spectroscopy. The results of this study indicated that acetone fraction had better radical scavenging activity against DPPH (IC50 = 0.76 mg/mL) and H2O2 (IC50 = 0.84 mg/mL) than ethyl acetate fraction against DPPH (IC50 = 1.10 mg/mL) and H2O2 (IC50 = 1.26 mg/mL) (p

The microwave-assisted extraction conditions for the optimal yield of extracts and total phenolic content (TPC) from Vernonia amygdalina leaf were optimized using a face-centered central composite design of response surface methodology. The independent parameters were viz: irradiation time (5–15 min), microwave power (400–600 W), temperature (90–110 °C), and feed-to-solvent ratio (1:8–1:12 g/mL). The optimal conditions for highest yield of extract (22.34% w/w) and TPC (102.24 mg GAE/g d.w.) were obtained at irradiation time of 8 min, microwave power of 416 W, temperature of 100 °C, and feed-to-solvent ratio of 1:8 g/mL. The quadratic model significantly (p

This paper contains data from the elemental and phytochemical profiling of black pepper oleoresin extracts using the LC-MS QToF and ICP-MS analysis. In recent years studies have shown the medicinal properties of extracts from these two cultivars of Piper nigrum. The medicinal properties are attributed to the presence of many secondary metabolites and mineral element in them. The phytochemical profiling was conducted using a Liquid Chromatography equipped with an electrospray time-of-flight mass spectrometer detectors. The mass spectrometer was equipped with an electrospray ionization sources operated in positive ion mode. The alkaloid compounds in the optimized black pepper extract were tentatively characterized in accordance with their ions׳ mass fragmentation.

Mushrooms are rich in pharmacologically-important phytochemicals with reported medicinal values. In this study, the antibacterial activity of Flammulina velutipes (Enoki), Hypsizygus tessellatus (brown (Buna shimeji) and white (Bunapi shimeji) variants) stem extracts prepared with different solvents (water, methanol, acetone, and ethyl acetate) was investigated against Escherichia coli (E. coli ATCC 25922), Serratia marscenscens (S. marscenscens ATCC14756), Bacillus subtilis (B. subtilis ATCC 23857), and Staphylococcus aureus (S. aureus ATCC 25923). Their antioxidant activities were evaluated using radical scavenging assays of 1,1-diphenyl-2-picrylhydrazyl (DPPH), hydrogen peroxide (H2O2) and ferric reducing power (FRP). The water extracts of Enoki, Buna shimeji, and Bunapi shimeji showed bacterial growth inhibition in a concentration-dependent manner. From the obtained results, all the Enoki extracts showed a significant inhibition of the gram positive bacterial species (E. coli and S. marcescens > 68%) and a reduced inhibition of the gram negative bacterial species (B. subtilis and S. aureus

The drying behavior of Vernonia amygdalina leaves was investigated using open sun and shade drying. The effective diffusivity coefficients for both methods were evaluated. Eight drying kinetics models were fitted to the experimental data obtained from the two drying methods; the goodness of fit was evaluated using three statistical tools, and the best model was selected. The Midilli and Kucuk model, which gave higher values of the coefficient of determination and lower values of the reduced chi-square and root mean square error was considered the best for predicting the drying behavior of open sun-dried and shade-dried V. amygdalina leaves with values of R of 0.99951 and 0.99981, RMSE of 0.00243 and 0.00253 and reduced chi-square of 0.000511 and 0.000428, respectively. The values of the effective diffusivity coefficients for open sun and shade drying were 26.58 × 10−10 m2/s and 52.77 × 10−11 m2/s, respectively. Furthermore, open sun drying resulted in severe deformity of the leaf morphology which may lead to degradation of the phytochemicals. Thus, shade drying was the better way of drying V. amygdalina leaves to preserve the nutrients compared to open sun drying. Keywords: Mathematical model, Shade drying, Sun drying, Vernonia amygdalina

In this study, ethanolic microwave-assisted extraction of total phenolic content (TFC), total flavonoid content (TFC) and antioxidant from Vernonia amygdalina leaf was investigated using response surface methodology. Four extraction variables, including irradiation time (1‒5 min), microwave power level (500‒700 W), feed-to-solvent ratio (1:8‒1:12 g/ml), and ethanol concentration (60‒80%) were optimized to obtain optimal yields. The analysis of variance results showed that ethanol concentration, microwave power level and irradiation time mostly affected the TFC, TPC and antioxidant activities significantly (p

In this study, the microwave-assisted extraction (MAE) variables were optimized using a face-centered central composite design of response surface methodology for optimal recoveries of total flavonoid content (TFC) and antioxidant capacities (DPPH and ABTS) of Vernonia amygdalina leaf extract. The independent variables were irradiation time (5–15 min), microwave power level (400–600 W), temperature (90–110 °C), and feed-to-solvent ratio (0.08–0.13 g/ml). The ANOVA results showed that TFC, DPPH and ABTS radical scavenging activities were significantly (p

In this study, the effects of extraction solvents on the yield and total phenolic content of Vernonia amygdalina leaf were examined. The considered solvents were water, 20% v/v ethanol, 40% v/v ethanol, 60% v/v ethanol, 80% v/v ethanol, and 100% v/v ethanol using Soxhlet extraction technique. Highest extraction yield (19.45 ± 0.22% g/g) and total phenolic content (96.25 ± 2.52 mg GAE/g d.w.) were achieved using 60% v/v aqueous ethanol solution. In addition, there exist a significant correlation between total phenolic content and antioxidant activities using DPPH (R2 = 0.9397, p

Black and white peppers are functional crops, used in food industries as spice and in traditional medicine, for the treatment of many degenerative diseases. This study investigated the influence of microwave heating on the extraction yield, energy absorption and dietary elemental composition of oleoresin extracts from black and white pepper. Under the largest donating rule, the maximum extract yield obtained was 48.22 mg/g from black pepper and 79.02 mg/g from white pepper microwave. The study therefore elucidated the energy absorption capacities in microwave heating and itsresultant effects on extraction yield. This clearly showed the potentials of microwave technology in obtaining high quality extracts with properly controlled parameters.

Vernonia amygdalina has been a known food and medicinal plants used in Asia and Africa (West Africa) due to its pharmacological effects (antioxidant, anti-diabetes, anti-inflammatory, anticancer, anti-malaria, and among others). The phytochemical studies revealed that this plant is enriched with proteins, fats, fibres, amino acids, minerals, vitamins, and carbohydrates. Many bioactive compounds had been isolated from its extracts. Therefore, this review summarized the overview of the bioactive compounds, phytochemical and pharmacological properties of V. amygdalina as well as its mechanism of action and toxicology.

Phaleria macrocarpa locally known as Mahkota Dewa is one of the important medicinal plants that originates from Papua Island, Indonesia and grows in tropical areas. Mangiferin is one of the major bioactive compounds of Phaleria macrocarpa. The effect of extraction time (4–6 h) and extraction temperature (90–110 °C) on the mangiferin yield were investigated using Face Centered Central Composite Design (FCCCD) with five centre points under Response Surface Methodology (RSM). The presence of mangiferin in the extract was confirmed using HPLC-DAD and the functional groups were identified through FTIR analyses. A second order polynomial model was employed in predicting the response. The regression analysis showed that more than 98% of the variation was explained by the models with the optimum of 38.7 mg/g mangiferin yield at 105 °C and 6 h extraction time. The experimental values show good accuracy with those predicted (1.1% deviation), thus indicating the suitability of the model employed and the success of FCCCD in optimizing the extraction conditions.

Background: Black- and white pepper extracts are natural products, which had been extensively used in food industries as a seasoning agent, and in herbal medicine for the treatment of many free radical-related diseases. Owing to the medicinal and nutritive benefits of this functional spice, the need then arises to find a way of extracting its fixed oil at optimum condition. Objectives: The aim of this study was to investigate the effect of extraction parameters on the extraction yield, antioxidant activities, microstructure, functional group characteristics, and elemental composition of fixed oils extracted from the two cultivars. Methods: Extraction of fixed oil was carried out using a heat reflux extraction technique. The dietary elemental composition was conducted using Energy Dispersive Spectroscopy (EDS). The effect of localized heating on the extracts was evaluated to determine the structural changes in the pepper sample using Brunauer-Emmett-Teller (BET) and Scanning Electron Microscopy (SEM). Results: The optimal fixed oil yields under the optimum condition were 10.38 mg/g for the black pepper and 15.27 for the white pepper. The antiradical powers (ARP) of 0.007985 and 0.009046 mL/µg were obtained for black- and white pepper fixed oil, respectively. This suggests that the fixed oil from white pepper exhibited higher antiradical characteristics than black pepper fixed oil. The results of BET-parameters revealed the percentage of deformations related to the black- and white pepper under the localized heating was 21.47% and 29.14%, respectively. Conclusions: The results revealed a greater deformation on the microstructure of white pepper than black pepper. Moreover, rich dietary elements present in the extracts succinctly unveiled the potential of fixed oil extracts in curative applications and preventive traditional medicine.

Carica papaya leaf is one of the considered agricultural waste; nevertheless, this leaf has been reported to contain diverse health benefits to humans. In as much as natural-based oils are of higher demands because of their aromatherapy property, this study focused on the extraction of oil from C. papaya leaf using microwave-assisted extraction (MAE) technique. Then, the extracted oil was analysed using gas chromatography-mass spectrometry. The influences of MAE parameters which include time of irradiation, microwave power, volume of solvent, and temperature on the extracted oil were investigated. The considered parameters were time of irradiation (30–180 min), microwave power (400–700 W), volume of the solvent used (distilled water) within the range of 100 to 300 mL, and temperature (40–100 °C). The outcomes from this finding showed that time of irradiation, microwave power and volume of solvent significantly altered the oil yield from C. papaya leaves. At the apex points of the considered parameters (time of irradiation, 120 min; microwave power, 500 W; volume of solvent, 200 mL; and temperature of 100 °C); the major identified compounds were n-Hexadecanoic acid; 9, 12, 15-Octadecatrienoic acid; phytol; 9-Octadecenoic acid; 9, 17-Octadecadienal; Oleic acid; and Octadecanoic acid. Therefore, C. papaya leaf is an embodiment of oil rich in fatty acid which can be employed as aromatherapy agent.

Vernonia amygdalina leaf has a significant importance in food and traditional medicine. It has been reported to possess various pharmacological effects. This study was carried out to investigate the influence of microwave-assisted extraction factors on the extraction from V. amygdalina leaves. The results highlighted that an increase in temperature deteriorated the yields of V. amygdalina leaf. Thus, shade-dried samples gave the highest yields at the irradiation times of 10 and 2 min, microwave power of 500 and 600 W, the temperature of 100 and 80°C, the feed-to-solvent ratio of 1:10, and ethanol concentration of 60% v/v using water and ethanol as the extracting solvents, respectively. Likewise, the antioxidant assay resulted in IC50 values of 260 ± 1.1 µg/mL DPPH and 149.78 ± 0.81 µg/mL ABTS for water and 204 ± 0.92 µg/mL DPPH and 31.17 ± 1.4 µg/mL ABTS for ethanol. Therefore, the synergistic mechanism of mass and heat transfer may be accounted for the accelerated extraction due to microwave energy.

Phaleria macrocarpa, commonly known as Mahkota dewa is a well-known medicinal plant native to Malaysia and Indonesia. P. macrocarpa has been used as traditional medicine for the treatment of many diseases for a long time. In this study, P. macrocarpa peels’ bioactive compounds were extracted using microwave-assisted extraction method. The effects of different process parameters such as irradiation time (0.5, 1, 3, 5, and 10 min), microwave temperatures (60, 70, 80, 90, and 100 °C) and microwave power (200, 300, 400, 500, and 600 W) on the extraction yield were investigated. Moreover, the antioxidant activity and total phenolic (TPC) content of the extract were estimated. The results reflected that the extraction yields, antioxidant activity and total phenolic content increased with increasing levels of process parameters to certain conditions where highest yields were attained. However, the best conditions of processing parameters that resulted to the highest amount of yield (61.25%) were 1 min, 80 °C and 300 W. The highest amount of antioxidant activity and TPC yield were 61.15±0.93% and 102.60±1.17 mg GAE/g d.w, respectively. These illustrated that P. macrocarpa peels can serve as a good source of antioxidant.

Fatty acids are reduced carbon chains mostly found in nature with different usages in the industrial feedstock, pharmaceutical and food industries. Plants are embodiments of substantial amounts of fatty acids. In this study, gas chromatography-mass spectrometry (GC–MS) analysis was employed to identify the chemical compositions of oils from Hibiscus sabdariffa flower, Stigma maydis; Chromolaena odorata leaf extracted through microwave-assisted hydrodistillation method. In addition, the oils from the three plant samples were characterized using Fourier transform infrared spectroscopy (FTIR) analysis to evaluate the fingerprints. A total number of 16, 13 and 13 chemical compounds were identified in the oils from H. sabdariffa flower, S. maydis and C. odorata leaf, respectively. The main identified compounds were fatty acids and esters. Moreover, the FTIR characterization reflected the presence of hydroxyl group, cellulose-fatty acids, methyl carboxylic acid, nucleic acid, and carbohydrate. This finding has fully demonstrated that the oils from H. sabdariffa flower, S. maydis and C. odorata leaf can serve as the potential sources of fatty acids.

Phaleria macrocarpa or Mahkota Dewa has been a unique plant because of its antioxidant, anti-inflammatory and anti-cancer properties. The phytochemical studies of this plant have revealed the presence of bioactive compounds: phenolic compound, terpenes (isoprenoids) compounds, alkaloids compounds, and benzophenones compounds. Researches done on its have shown its ability to treat some diseases and serves as herbal medicines. The aim of this review is to summarize and evaluate the existing researches regarding the pharmacological effects, phytochemical properties, and toxicological studies of Phaleria macrocarpa. This review is expected to be useful for researchers working on the potential roles of Phaleria macrocarpa in the treatment of diseases or for product development.