Phytochemical, Antioxidant Activity, and Toxicity of Wild Medicinal Plant of Melitotus albus Extracts, In Vitro and In Silico Approaches.

Morocco is known for its high plant biodiversity, but many plants are poorly valorized. For this reason, this study aims to valorize the methanolic and aqueous extracts of Melitotus albus leaves by studying their antioxidant activity and toxicity. The extracts' antioxidant activity is assessed using the FRAP, DPPH, CAT, and ABTS methods. The chemical composition was determined using LC-MS analysis and evaluated using in silico studies. The results revealed that the total polyphenol content of the aqueous extract, 259.26 ± 7.79 (mg GAE/g), is higher than that of the methanolic extract, 131.41 ± 12.64 (mg GAE/g). The antioxidant activity by the methods of DPPH, ABTS, and phosphor molybdenum of aqueous extracts (0.087 ± 0.015, 0.014 ± 0.001 and 6.157 ± 1.050 mg eq vit C/g, respectively) is greater than that of methanolic extracts (0.107 ± 0.02, 0.167 ± 0.03, and 0.453 ± 0.014 mg eq vit C/g, respectively). The reducing power of iron (FRAP) shows that the methanolic extract has a greater reducing power than that of the aqueous extract with a low IC50 (0.011 ± 0.003 and 0.199 ± 0.016 mg/mL, respectively). The study of acute and subacute toxicity shows that the administration of the aqueous extract of M. albus at different doses increases the body weight of rats without modifying their general behavior. The M. albus extract had a 99.99% total phenolic content, as determined by LC-MS, consisting of 12 different components. The primary constituents of the extract are chlorogenic acid (43.68%), catechin/epicatechin (24.82%), quercetin-3-O-glucuronic acid (9.91%), naringin (7.64%), and p-hydroxybenzoic/salicylic acid (2.95%). The in-silico study showed that these compounds can passively permeate through the blood and have a beneficial effect on various organs of the body. Based on these results, M. albus can be used as a medicinal plant in phytotherapy, cosmetics, or as a dietary supplement. The bioactive compounds of these plants will require a lot of further effort in terms of isolation and characterization.

Impact of Climate Change on the Chemical Compositions and Antioxidant Activity of Mentha pulegium L.

A central position in Moroccan ethnobotany is held by the Mentha genus, serving as a vital reference for aromatic and medicinal plants within the Lamiaceae family. The profound importance of Mentha species in the daily lives of Moroccans is recognized, and the primary objective of this study is to assess the impact of rising temperatures and decreasing precipitation on the primary and secondary metabolites of Mentha pulegium under the following climatic conditions: sample 1, cultivated under standard temperature and precipitation conditions during the first year; sample 2, subjected to an 8 °C temperature increase and a 25% reduction in water supply; and sample 3, exposed to a 12 °C temperature rise and a 50% decrease in water availability. Phytochemical screening results reveal a progressive decline in primary metabolites from sample 1 to sample 3 due to the increase in temperature and decrease in precipitation. Conversely, a distinct trend is observed in secondary metabolites and the yield of essential oil, increasing from sample 1 to sample 2 as the temperature rises and precipitation decreases. Remarkably, in sample 3, the yield of essential oil decreases as climatic conditions further deteriorate. Additionally, GC analysis demonstrates that modifications in the chemical compositions of essential oils occur because of the disruption of climatic parameters, particularly in the major compounds. Similarly, changes in climatic parameters significantly influence antioxidant activity, with sample 2 exhibiting the highest activity, as reflected by an IC50 value (half-maximal inhibitory concentration) of 14,874.04 µg/mL, followed by the third sample at 8488.43 µg/mL, whereas the first sample exhibits the lowest activity at 4505.02 µg/mL. In summary, the complex relationship between climatic factors and the chemical composition of Mentha pulegium is highlighted by our experiment, emphasizing its implications for medicinal properties within an ecological context.

Chemical Composition of Essential Oils from Nepeta transcaucasica Grossh. and Nepeta cataria L. Cultivated in Bulgaria and Their Antimicrobial and Antioxidant Activity.

The genus Nepeta, belonging to the family Lamiaceae, includes about 300 species, most of which are used in folk medicine due to their pronounced biological properties. The aim of the present study was to evaluate the agrobiological characteristics of Nepeta transcaucasica (N. transcaucasica) Grossh. and Nepeta cataria (N. cataria) L., cultivated in Bulgaria, and obtain their essential oils and determine their antimicrobial and antioxidant activities. The agrobiological characteristics of the two species growing in Kazanlak were analyzed; therefore, high variability in the population of N. transcaucasica and comparative homogeneity in N. cataria was shown. The species N. transcaucasica contained 0.28% essential oil with main components ß-citronellol (52.05%), eucalyptol (7.34%), ß-citronellal (6.06%), germacrene D (5.45%), (Z)-ß-ocimene (5.14%), and ß-caryophyllene (3.06%). The species N. cataria consisted of 0.19% essential oil with main components ß-citronellol (26.31%), geraniol (15.92%), neral (11.45%), nerol (9.56%), carvacrol (6.04%), and ß-citronellal (5.35%). The antibacterial activity against Gram-positive bacteria Listeria monocytogenes and Staphylococcus aureus and Gram-negative bacteria Escherichia coli (E. coli) and Salmonella enterica subsp. enterica serovar Abony was determined. The essential oils showed antimicrobial activity only against E. coli. The diameters of the inhibition zones were found to be 26 mm for the species N. transcaucasica and 10 mm for the species N. cataria. The antioxidant activity of the two essential oils was also determined by four different methods, DPPH, ABTS, FRAP, and CUPRAC, with the highest values for the ABTS radical, for the species N. transcaucasica (48.72 µM TE/mL), and the species N. cataria (310 µM TE/mL).

Evaluation of the Effect of Four Bioactive Compounds in Combination with Chemical Product against Two Spider Mites Tetranychus urticae and Eutetranychus orientalis(Acari: Tetranychidae).

Currently, pests control using chemical acaricides constitutes worries for ecologists and health care people as these chemical products create damage to the ecosystem as well as the development of spider mites resistance. Such concerns request deep and rapid feedback by looking for new alternative and eco-friendly methods. In recent years, a new field is evolving in the use of essential oils in pest management practices. Essential oils have been considered as potential pest management agents, because they demonstrate to have a broad range of bioactivity, possess contact, and fumigant toxicity. In addition, the major advantages of many plant-based acaricides lie in their low toxicity to agroecosystems. Botanical acaricides composed of essential oils may prove to be a good choice for the more persistent synthetic acaricides. In this study, the acaricidal effect of four plant-derived essential oils against adults of the two important crop pests, Tetranychus urticae (Koch) 1836 and Eutetranychus orientalis (Klein) 1936 are studied. The fumigant toxicity revealed that all the essential oils tested Mentha pulegium L., Lavandula stoechas L., Rosmarinus officinalis L., and Origanum compactum Benth (Lamiaceae family) displayed an acaricidal effect. At the highest dose (625 µl/ml), mortalities recorded were found between 91 and 98% and 92 and 99% at 24 and 48 h, respectively, for T. urticae, and between 90 and 98% and 94 and 99% at 24 and 48 h, respectively, for E. orientalis. The M. pulegium L. essential oil represents the highest activity against E. orientalis and T. urticae. For the binary combination between the EOs (essential oils) and the acaricide based on the active ingredient acequinocyl, the results showed that the mixture of O. compactum EO (essential oil) + acequinocyl exhibited an important acaricidal effect on T. urticae and E. orientalis with 99% at 24 h and 100% at 48 h of mortality, followed by M. pulegium EO + acequinocyl with 92% at 24 h and 95% at 48 h for T. urticae as well as 99% at 24 h and 100% at 48 h for E. orientalis of mortality. Whereas, the mixture of L. stoechas EO + acequinocyl presented the lowest activity against T. urticae and E. orientalis with 82-87% at 24 h and 86-90% at 48 h, respectively. The mixtures (M. pulegium EO + acequinocyl, R. officinalis EO + acequinocyl, and O. compactum EO + acequinocyl) exerted a high acaricidal effect against E. orientalis. These promising results could help to develop botanical pesticides that could be used in integrated pest management.

In Vitro Study of the Phytochemical Composition and Antioxidant, Immunostimulant, and Hemolytic Activities of Nigella sativa (Ranunculaceae) and Lepidium sativum Seeds.

The Moroccan flora abounds and is an important reserve of medicinal plants. Nigella sativa and Lepidium sativum are plants that are widely used in traditional medicine for their multiple therapeutic properties. The current study aims to highlight the biological activities that can justify and valorize the use of these plants. Flavonoids, total phenols, condensed tannins, and sugars were determined. The biological activities tested were antioxidant by determining the IC50 (defined as the concentration of an antioxidant required to decrease the initial concentration by 50%; inversely related to the antioxidant capacity), hemagglutination, and hemolytic activities. Phytochemical quantification of the seed extracts indicated that the total phenol content was largely similar for both plants and in the order of 10 mg GAE (Gallic acid equivalent)/g. On the other hand, L. sativum seeds registered a higher content of flavonoids (3.09 ± 0.04 mg QE (quercetin equivalent)/g) as compared to Nigella saliva (0.258 ± 0.058). Concerning condensed tannins, N. saliva seeds present a higher amount with a value of 7.2 ± 0.025 mg/g as compared to L. sativum (1.4 ± 0.22 mg/g). Concerning the total sugar content, L. sativum shows a higher content (67.86 ± 0.87 mg/g) as compared to N. sativa (58.17 ± 0.42 mg/g); it is also richer in mucilage with a content of 240 mg as compared to 8.2 mg for N. saliva. Examination of the antioxidant activity using a DPPH (2.2-diphenyl 1-pycrilhydrazyl) test revealed that the EButOH (n-butanol extract) and EAE (ethyl acetate extract) extracts were the most active, with IC50 values of 48.7 and 50.65 µg/mL for the N. sativa extracts and 15.7 and 52.64 µg/mL for the L. sativum extracts, respectively. The results of the hemagglutination activity of the different extracts of the two plants prepared in the PBS (phosphate-buffered saline) medium showed significant agglutination for the L. sativum extract (1/50) compared to the N. sativa extract (1/20). An evaluation of the hemolytic effect of the crude extract of the studied seeds on erythrocytes isolated from rat blood incubated in PBS buffer compared to the total hemolysis induced by distilled water showed a hemolysis rate of 54% for Nigella sativa and 34% for L. sativum. In conclusion, the two plants studied in the current work exhibited high antioxidant potential, which could explain their beneficial properties.

Total Polyphenols Content, Antioxidant and Antimicrobial Activities of Leaves of Solanum elaeagnifolium Cav. from Morocco.

Solanum elaeagnifolium is among the invasive plants of Morocco; studies on its chemical composition and biological activities are few in number in Morocco. S. elaeagnifolium has shown molluscicidal and nematicidal and cancer-inhibitory effects, anti-inflammatory, analgesic activity, and antibacterial activity. The objective of this research is to improve this plant and assess its antibacterial and antioxidant properties as well as its total polyphenolic content (TPC) and total flavonoid content (TFC). The Folin-Ciocalteu method and the aluminium-trichloride method were used to determine TPC and TFC in hydro-ethanolic (HEE) and hydro-acetonic (HAE) leaf extract. Three assays were performed to determine the antioxidant activity: the DPPH test (radical 2,2'-diphenyl-1-picrylhydrazyl), the FRAP test (Ferric Reducing Antioxidant Power), and the TAC test. Disk diffusion and microdilution were used to test antibacterial activity against four pathogenic bacteria and Candida albicans. The hydro-ethanolic extract 2.54 ± 0.4 mg EAG/g has a greater polyphenol concentration than the hydro-acetonic extract 1.58 ± 0.03 mg EAG/g. Although the flavonoid content of the hydro-acetonic extract (0.067 ± 0.001 mg EQ/g) is larger than that of the hydro-ethanolic extract (0.012 ± 0.001 mg EQ/g), the flavonoid content of the hydro-ethanolic extract (0.012 ± 0.001 mg EQ/g). The DPPH values were IC-50 = 0.081 ± 0.004 mg/mL for hydro-ethanoic extract and 0.198 ± 0.019 mg/mL for hydro-acetonic extract, both extracts superior to BHT (0.122 ± 0.021 g/mL). While the FRAP assay showed a low iron-reducing power values for both extracts compared to BHT), the overall antioxidant activity of the two extracts was found to be considerable. The overall antioxidant activity of the hydro-ethanolic extract was 8.95 ± 0.42 mg EAA/g, whereas the total antioxidant activity of the hydro-acetonic extract was 6.44 ± 0.61 mg EAA/g. In comparison with the antibiotic Erythromycin, HAE and HEE from S. elaeagnifolium leaves demonstrated significant antibacterial action. HAE had the best inhibitory efficacy against Bacillus subtilis DSM 6333, with an inhibition diameter of 10.5 ± 0.50 mm and a MIC of 7.5 ± 0.00 mg/mL, as well as against Proteus mirabilis ATCC 29906, with an inhibitory diameter of 8.25 ± 0.75 mm and a MIC of 15 ± 0.00 mg/mL.

Chemometric Investigation and Antimicrobial Activity of Salvia rosmarinus Spenn Essential Oils.

To ensure the better production and sustainable management of natural resources, a chemometric investigation was conducted to examine the effect of cooperative and harvesting periods on the crop yields and chemical compositions of Salvia rosmarinus Spenn essential oils in the Oriental region of Morocco. The samples were collected from three cooperatives over nine time periods from January 2018 to April 2019. The chemical composition of Salvia rosmarinus Spenn essential oils was analyzed by gas chromatography coupled with mass spectrometry. The data from this study were processed by multivariate analyses, including principal component analysis (PCA) and hierarchical cluster analysis (HCA). The disc diffusion technique and a determination of the minimal inhibitory concentration were performed to study the antibacterial properties of the oils. Statistical analysis showed that the cooperative and harvest period have a significant effect on yields. The highest yield of essential oil was recorded in April 2019 at cooperative C1. The PCA and the HCA results were divided into two groups: Group A for the summer season and group B for the winter season. The samples collected during summer were characterized by a high amount of 1,8-cineole component and a high yield of essential oil, whereas the samples collected during winter were qualified by a high amount of α-pinene component and a low yield of essential oil. The antibacterial activity of Salvia rosmarinus Spenn essential oils showed that Mycobacterium smegmatis ATCC23857 and Bacillus subtilis ATCC 23857 are the most susceptible strains, stopping growth at 1/500 (v/v). The least susceptible strain is Escherichia coli ATCC25922, with an MIC value corresponding to 1/250 (v/v). The findings of this study could have a positive economic impact on the exploitation of rosemary in the Oriental region, especially during the best harvest periods, as they indicate how to obtain the best yields of oils richest in 1,8-cineole and α-pinene chemotypes.

In Vitro Studies on the Antimicrobial and Antioxidant Activities of Total Polyphenol Content of Cynara humilis from Moulay Yacoub Area (Morocco).

In Morocco, Cynara humilis L. is used in traditional medicine. The objective of this research was to research the antioxidant and antimicrobial properties of hydroethanolic extracts from the C. humilis plant's leaves and roots. The content of polyphenols and flavonoids was evaluated using Folin-Ciocalteu's and aluminum chloride assays. Two techniques were used to evaluate antioxidant properties: antioxidant capacity in total (TAC) and 2,2-diphenyl-1-picrylhdrazyl (DPPH). In antimicrobial assays, five pathogenic microbial strains were studied including two Escherichia coli, one coagulase-negative Staphylococcus and Klebsiella pneumoniae, and one Candida albicans, by two techniques: agar disk diffusion and microdilution. Leaves had a greater content of flavonoids 27.07 mg QE/g of extract and the polyphenols 38.84 mg GAE/g of extract than root 24.39 mg QE/g of extract and 29.39 mg GAE/g of extract, respectively. The TAC test value of the 0.77 mg AAE/g extract in the leaf extract was found to be significantly greater than that of the 0.60 mg EAA/g extract in the root extract. The DPPH antioxidant assay IC50 values of the root and leaf extract were 0.23 and 0.93 µg/mL, respectively. C. humilis extracts showed an antimicrobial effect against all tested strains, the inhibitory zone (DIZ) have values in the range between 12 and 15 mm. Moreover, the root extract showed the lowest minimum inhibitory concentration (MIC) against coagulase-negative Staphylococcus with an IC50 value of 6.25 mg/mL. The higher content of flavonoids and polyphenols in the hydroethanolic extracts of C. humilis leaves and roots demonstrates that they have a significant antimicrobial and antioxidant effect, as found in this study.

Contribution to the Evaluation of Physicochemical Properties, Total Phenolic Content, Antioxidant Potential, and Antimicrobial Activity of Vinegar Commercialized in Morocco.

Vinegar is a natural product widely used in food and traditional medicine thanks to its physicochemical properties and its richness in bioactive molecules. However, its direct use by consumers can have complications and undesirable effects. Therefore, this study contributes to investigating the physicochemical and biological properties of eleven vinegars marketed in Morocco. Determination of pH, acetic acid, conductivity, total soluble solids and alcohol content in vinegar was carried out. The polyphenols (TP), flavonoids (TF), and condensed tannins (CT) content was determined, and their antioxidant activities were evaluated using 2,2-diphenyl-1-picryl Hydrazyl (DPPH), Ferric Reducing Antioxidant Power (FRAP) and Phosphomolybdenum Reduction Assay (TAC). Then, the antimicrobial activity was studied against four pathogenic bacteria and two fungal strains, using the disk diffusion and the microdilution method. This study showed a wide range of acetic acid values from 0.65 ± 0.29 to 5.15 ± 0.20%. The high value of TP, TF, and CT in our samples V10, V9, and V4 was 655.00 ± 22.2 µgGAE/mL, 244.53 ± 11.32 µgQE/mL and 84.63 ± 1.00 µgTAE/mL, respectively. The tested strains showed variable sensitivities to the different samples with inhibition zones ranging from 6.33 ± 2.08 to 34.33 ± 0.58 mm. The lowest minimum inhibition concentrations were recorded against Staphylococcus aureus ATCC29213 ranging from 1.95 to 7.81 µL/mL. While Aspergillus niger ATCC16404 showed resistance against all of the analyzed samples. In general, vinegar commercialized in Morocco presents a variable range of products with variable properties. Indeed, must take into account this diversity when using it. A future study is needed to identify the phytochemical composition that will further the comprehension of this variability and contribute to its valorization.

Antimicrobial and Antioxidant Properties of Total Polyphenols of Anchusa italica Retz.

Anchusa italica Retz has been used for a long time in phytotherapy. The aim of the present study was to determine the antioxidant and antibacterial activities of extracts from the leaves and roots of Anchusa italica Retz. We first determined the content of phenolic compounds and flavonoids using Folin-Ciocalteu reagents and aluminum chloride (AlCl3). The antioxidant activity was determined using three methods: reducing power (FRAP), 2.2-diphenyl-1-picrylhydrazyl (DPPH), total antioxidant capacity (TAC). The antimicrobial activity was investigated against four strains of Escherichia coli, two strains of Klebsiella pneumoniae and coagulase-negative Staphylococcus, and one fungal strain of Candida albicans. The results showed that the root extract was rich in polyphenols (43.29 mg GAE/g extract), while the leave extract was rich in flavonoids (28.88 mg QE/g extract). The FRAP assay showed a strong iron reduction capacity for the root extract (IC50 of 0.11 µg/mL) in comparison to ascorbic acid (IC50 of 0.121 µg/mL). The DPPH test determined an IC50 of 0.11 µg/mL for the root extract and an IC50 of 0.14 µg/mL for the leaf extract. These values are low compared to those for ascorbic acid (IC50 of 0.16 µg/mL) and BHT (IC50 0.20 µg/mL). The TAC values of the leaf and root extracts were 0.51 and 0.98 mg AAE/g extract, respectively. In vitro, the extract showed inhibitory activity against all strains studied, with diameters of zones of inhibition in the range of 11.00-16.00 mm for the root extract and 11.67-14.33 mm for the leaf extract. The minimum inhibitory concentration was recorded for the leaf extract against E. coli (ATB:57), corresponding to 5 mg/mL. Overall, this research indicates that the extracts of Anchusa italica Retz roots and leaves exert significant antioxidant and antibacterial activities, probably because of the high content of flavonoids and polyphenols.

The Impact of Apple Variety and the Production Methods on the Antibacterial Activity of Vinegar Samples.

Apple vinegar is a natural product widely used in food and traditional medicine as it contains many bioactive compounds. The apple variety and production methods are two factors that play a major role in determining the quality of vinegar. Therefore, this study aims to determine the quality of apple vinegar samples from different varieties (Red Delicious, Gala, Golden Delicious, and Starking Delicious) prepared by three methods using small apple pieces, apple juice, and crushed apple, through determining the physicochemical properties and antibacterial activity of these samples. The antibacterial activity was studied against five pathogenic bacteria: Staphylococcus aureus, Klebsiella pneumonia, Escherichia coli (ATB: 57), Escherichia coli (ATB: 97), and Pseudomonas aeruginosa, using two methods, disk diffusion and microdilution, for determining the minimum inhibitory concentrations and the minimum bactericidal concentrations. The results of this study showed that the lowest pH value was 3.6 for Stark Delicious, obtained by liquid fermentation, and the highest acetic acid values were 4.7 and 4% for the vinegar of Red Delicious and Golden Delicious, prepared by solid fermentation, respectively. The results of the antibacterial activity showed considerable activity of apple vinegar on the tested strains. Generally, the Staphylococcus aureus strain appears less sensitive and Pseudomonas aeruginosa seems to be very sensitive against all samples, while the other strains have distinct sensitivities depending on the variety studied and the method used. A higher antibacterial activity was found in vinegar obtained by the apple pieces method and the Red Delicious variety, with a low MIC and MBC recorded, at 1.95 and 3.90 µL/mL, respectively. This study has shown that the choice of both apple variety and production method is therefore an essential step in determining and aiming for the desired quality of apple vinegar.