Chemical composition and antioxidant activities of essential oils and methanol extracts of three wild Lavandula L. species

A comparative study of essential oil composition, polyphenol content and antioxidant activities of Lavandula coronopifolia, Lavandula multifida and Lavandula stoechas subsp. stoechas were reported. Qualitative and quantitative variations in the composition of oils according to species were shown. Lavandula coronopifolia's oil was characterised by high proportions of trans-β-ocimene (26.9%), carvacrol (18.5%), β-bisabolene (13.1%) and myrcene (7.5%). The main components of L. multifida oil are carvacrol (65.1%) and β-bisabolene (24.7%). Lavandula stoechas oil is rich in fenchone (34.3%) and comphor (27.4%). The total phenolic and flavonoid contents also significantly varied among species. Lavandula coronopifolia exhibits the highest phenolic and flavonoid contents (31.3?mg GAE?g(-1) and 16.3?mg RE?g(-1), respectively), followed by L. multifida (30.8?mg GAE?g(-1) and 12.3?mg RE?g(-1)). Methanolic extracts and essential oils displayed significant antioxidant activities. The level of antioxidant capacity varied according to extracts and species.     

Bioactivity-guided study of antiproliferative activities of Salvia extracts

The cytotoxic activities of the n-hexane, chloroform and aqueous methanolic fractions prepared from the methanolic extract of the leaves of 23 Salvia taxa were studied for their cell growth-inhibitory activity against human cervix adenocarcinoma (HeLa), skin carcinoma (A431) and breast adenocarcinoma (MCF7) cells using the MTT assay. The n-hexane fractions of six Salvia taxa (S. hispanica, S. nemorosa, S. nemorosa 1. albiflora, S. pratensis, S. recognita and S. ringens) and the chloroform fraction ofS. officinalis 1. albiflora produced over 50% growth inhibition of the skin carcinoma cell line. None of the tested extracts showed substantial (above 50%) antiproliferative effects against HeLa and MCF7 cells. S. ringens was the most powerful among the studied Salvia species with a 61.8% cell growth inhibitory activity on A431 cells. In the case of S. ringens, other plant parts were also tested for antiproliferative effect, and the highest activities were recorded for the root extract. This was subjected to bioactivity-guided fractionation, which yielded four abietane diterpenes (royleanone, horminone, 7-O-methyl-horminone and 7-acetyl-horminone), one triterpene (erythrodiol-3-acetate) and beta-sitosterol. Horminone, 7-acetyl-horminone and erythrodiol-3-acetate displayed marked concentration-dependent antiproliferative effects, while royleanone and 7-O-methyl-horminone produced weaker activities.     

Chemical composition and antioxidant activities of extracts from Apocyni Veneti Folium

An expeditious and effective HPLC-UV method has been developed for the simultaneous determination of seven major flavonoids in Apocyni Veneti Folium (AVF) extract. The chemical profile of seven flavonoids, including quercetin-3-O-β-D-glc(2?→?1)-β-D-glucoside, rutin, isoquercetin, kaempferol-3-O-β-D-glucoside, quercetin-3-O-(6″-O-malonyl)-β-D-glucoside, quercetin and kaempferol was acquired by HPLC-UV. The analysis was performed on a Diamosil C18 analytical column with a gradient solvent system of acetonitrile-0.1% aqueous acetic acid. Full validation of the method was carried out (linearity, reproducibility, repeatability, accuracy and limit of detection). The results indicated that the contents of investigated flavonoids in Apocyni Veneti Folium varied significantly from habitat to habitat, with contents ranging from 0.01 to 5.57 mg g?1. The antioxidant activity results demonstrate that the seven flavonoids showed great efficiency in scavenging DPPH radicals. The high content of flavonoid components of AVF could be responsible for its high antioxidant activity. This study provides powerful evidence for the relationship between the chemical ingredients of and bioactivity in AVF.     

Antioxidant,antimicrobial and urease inhibiting activities of methanolic extracts from Cyphostemma digitatum stem and roots

Cyphostemma digitatum stem and roots extracts were investigated for antioxidant, antimicrobial, urease inhibition potential and phytochemical analysis. Phytochemical screening of the roots and stem extract revealed the presence of secondary metabolites including flavonoids, alkaloids, coumarins, saponins, terpenoids, tannins, carbohydrates/reducing sugars and phenolic compounds. The methanolic extracts of the roots displayed highest antioxidant activity (93.518%) against DPPH while the crude methanolic extract of the stem showed highest antioxidant activity (66.163%) at 100 μg/mL concentration. The methanolic extracts of both stem and roots were moderately active or even found to be less active against the selected bacterial and fungal strains (Tables S2 and S3). The roots extract (methanol) showed significant urease enzyme inhibition activity (IC₅₀ = 41.2 ± 0.66; 0.2 mg/mL) while the stem extract was found moderately active (IC₅₀ = 401.1 ± 0.58; 0.2 mg/mL) against thiourea (IC₅₀ = 21.011; 0.2 mg/mL).     

Polyphenolic contents and antioxidant activities of aerial parts of Salvia multicaulis from the Iran flora

Abstract

Folk medicine sometimes involves the use of salvia species for therapeutic purposes. Polyphenols with the highest amounts included rosmarinic acid (7.358mg/g), catechin (1.5?mg/g), vanillin (1.00?mg/g), chlorogenic acid (0.53?mg/g), quercetin (0.16?mg/g), and p-coumaric acid (0.015). Furthermore, the results showed that S. multicaulis has a high content of total phenol (4.39?mg/g) and DPPH activity (8.44?mg/g). Salvia multicaulis could be potentially used as a medicinal plant because of its antioxidant activity and polyphenol content.     

Comparative chemical diversity and antioxidant activities of three species of Akebia herbal medicines

Akebia stem has long been used extensively as a rare Chinese herbal medicine. The three most significant Akebia medicinal species are Akebia quinata (Thunb.) Decne. (A. quinata), Akebia trifoliata (Thunb.) Koidz. (A. trifoliata), and Akebia trifoliata (Thunb.) Koidz. var. Australis (Diels) Rehd. (A. trifoliata. var). They have significant therapeutic effects and are widely used in the pharmaceutical and cosmetics industries. Only a few studies compared their chemical differences and antioxidant activities. To better demonstrate each species' characteristics and antioxidant properties, the ultra-performance liquid chromatography coupled with quadrupole Orbitrap mass spectrometry (UPLC-Q-Orbitrap/MS)-based metabolomics was applied to investigate the chemome diversity of three Akebia species. Their antioxidant activities were evaluated by DPPH and ABTS assays. In total, 65 different metabolites were identified, including 5 phenolic acids, 2 phenylpropanoids, 4 lignan glycosides, and 54 triterpenoid saponins. The different aglycone types of triterpenoid saponins were found to be the component differences between the three Akebia species. The chemical composition of A. trifoliata and A. trifoliata. var is similar. The 2-(3,4-dihydroxyphenyl)-ethyl-O-β-d-glucopyranoside has been found only in A. quinata. In contrast, the triterpenoid saponins akemisaponin B, akemisaponin D, oleanolic-acid-3-O-arabinopyranosyl-28-O-glucopyranosyl-glucopyranosyl-rhamnopyranosyl-arabinopyranosyl, akemisaponin C and saponin P_j1 have been found A. trifoliata and A. trifoliata. var. As a result, these six compounds can be considered marker compounds that distinguish three Akebia species. The antioxidant activities results indicated that the antioxidants of three Akebia species were the same in different antioxidative test systems. A. trifoliata (IC₅₀: 2.28–6.97 mg·mL^?1) and A. trifoliata. var (IC₅₀: 2.09–6.87 mg·mL^?1) showed 2–3 times higher antioxidant activity than A. quinata (IC₅₀: 5.56–11.21 mg·mL^?1). This study reveals the antioxidant activity differences of three Akebia species, laying a foundation for further development and utilization. This type of study can lead to the identification of a compound that, with further work and more extensive studies, has the potential to be used as a biomarker, in this case to distinguish different medicinal species.     

Antimicrobial and antioxidant activities of new metal complexes derived from 3-aminocoumarin

3-Aminocoumarin (L) has been synthesized and used as a ligand for the formation of Cr(III), Ni(II), and Cu(II) complexes. The chemical structures were characterized using different spectroscopic methods. The elemental analyses revealed that the complexes where M=Ni(II) and Cu(II) have the general formulae [ML(2)Cl(2)], while the Cr(III) complex has the formula [CrL(2)Cl(2)]Cl. The molar conductance data reveal that all the metal chelates, except the Cr(III) one, are non-electrolytes. From the magnetic and UV-Visible spectra, it is found that these complexes have octahedral structures. The stability for the prepared complexes was studied theoretically using Density Function Theory. The total energy for the complexes was calculated and it was shown that the copper complex is the most stable one. Complexes were tested against selected types of microbial organisms and showed significant activities. The free radical scavenging activity of metal complexes have been determined by measuring their interaction with the stable free radical DPPH and all the compounds have shown encouraging antioxidant activities.     

Antimicrobial and antiparasitic activities of three algae from the northwest coast of Algeria

The objective of this study was to investigate the biological activities of Algerian algae, Sargassum vulgare, Cladostephus hirsutus and Rissoella verruculosa. Antimicrobial activity of the crude extracts and their fractions was assessed using the disc diffusion assay, the minimum inhibitory concentration and the minimum bactericidal concentration. Antiparasitic activity was studied in vitro against the blood stream forms of Trypanosoma brucei brucei and the intraerythrocytic stages of Plasmodium falciparum. Ethyl acetate (EA) fractions of the three tested algae showed more potent antimicrobial activity against S. aureus (7–14.5 mm) and B. cereus (7–10.75 mm), MIC values ranged from 0.9375 to 7.5 mg mL^?1 and MBC values > 15 mg mL^?1. Concerning the antiparasitic activity, EA factions of S. vulgare (IC₅₀ = 9.3 μg mL^?1) and R. verruculosa (IC₅₀ = 11.0 μg mL^?1) were found to be more effective against T. brucei brucei, whereas the three EA fractions were little active against P. falciparum.     

Chemical composition,antimicrobial and antioxidant activities of the essential oils of three Uzbek Lamiaceae species

The chemical composition of the essential oil from the aerial parts of three Lamiaceae species from Uzbekistan was investigated by GC-MS analysis. β-Linalool (26.6%), α-terpineol (10.0%), coumarin (8.9%) and 4,5,7,7α-tetrahydro-4,4,7α-trimethyl-2(6H)-benzofuranone (5.4%) resulted as the main components of Ajuga turkestanica essential oil, while camphene (17.1%), 1,8-cineole (15.9%), β-cymene (7.9%) and limonene (7.4%) in Phlomis regelii. The essential oil of Thymus seravschanicus was dominated by thymol (37.5%), phellandral (26.0%), τ-terpinene (6.6%) and β-cymene (5.2%). The essential oils had considerable antimicrobial activity against different bacterial strains and fungi. Among the tested samples of essential oils, P. regelii essential oil has the significant antioxidant activity with IC₅₀ value of 117.8 ± 8.02 μg/mL.     

Chemical composition,antibacterial and antioxidant activities of essential oils from leaves of three Melaleuca species of Pakistani flora

This study presents essential oil composition of three Melaleuca species namely, Melaleuca bracteata F. Muell, Melaleuca fulgens R. Br. subsp. steedmanii and Melaleuca leucadendron (L.) L. collected from different regions of Pakistan. The chemical composition of essential oils was analyzed by GC-FID and GC–MS. Eugenol methyl ether was identified as a principal component in M. bracteata (82.3%), M. fulgens (87.8%) and M. leucadendron (95.4%) oils. In vitro antibacterial studies were done by agar well diffusion and microdilution method and the tested essential oils exhibited bacteriostatic and bactericidal effects against the tested foodborne pathogens at 4–8 µg/ml. Time kill assay showed significant bactericidal effect of oils for four weeks. The antioxidant potential was assessed by free radical scavenging activity and reducing power assay. The oils showed strong antioxidant activity with approximately 89.0–89.5% inhibition of 2,2-diphenyl-1-picrylhydrazyl radical and ferric reducing power in the range of 1.94 ± 0.007–2.04 ± 0.04% at 100 µg/ml.     

Assessment of antioxidant activities of three wild medicinal plants from Bahrain

This study reports the antioxidant properties of three wild medicinal plants from Bahrain, namely Aizoon canariense L., Asphodelus tenuifolius Cav., and Emex spinosus (L.) Campdera. Antioxidant and antiradical activities of dried materials of these plants were investigated using FRAP, DPPH and ABTS assays. Total phenolics, free phenolics and total flavonoids were also determined. E. spinosus was ranked by the assays as the plant possessing the highest antioxidant and antiradical activities with an average FRAP value of 1.84 mmol/g and IC₅₀ of 10.7 and 7.75 mg/ml for DPPH and ABTS assays, respectively. A. tenuifolius ranked second with a mean FRAP value of 0.69, IC₅₀ DPPH of 1.72 and ABTS of 0.36. A. canariense possessed the lowest activities with a mean FRAP value of 0.6, and averaged IC₅₀ of 103.8 and ABTS of 14.6. E. spinosus possessed the highest content of free phenolics (mg/100 g) (64.64) followed by A. tenuifolius (45.21) and A. canariense (32.23). E. spinosus also exhibited the highest total flavonoids with an average 82.71 mg/100 g followed by A. canariense (55.92) and A. tenuifolius (49.10). The studied medicinal plants possess considerable antioxidant activities and may contribute to the well-being of individuals who consume them.     

Antimicrobial and antioxidant activities of the flower essential oil of Halimodendron halodendron

The essential oil obtained by hydro-distillation from the flowers of Halimondendron halodendron (Leguminosae) was analyzed for its chemical composition by gas chromatography-mass spectrometry (GC-MS). Undecane (16.4%), dodecane (15.3%), tridecane (12.5%), decane (8.2%), 6,10,14-trimethyl-pentadecan-2-one (6.3%), methyl palmitate (6.0%), methyl linolenate (4.1%) and ethylcyclohexane (4.1%) were the major compounds of the thirty-five identified components of the oil. The essential oil was shown to have a broad spectrum of antimicrobial activity with MIC values ranging from 100 to 250 microg/mL, and IC50 values from 40.4 to 193.8 microg/mL. The oil also showed strong antioxidant activity, with an especially high metal chelating capacity of ferrous ions with an IC50 value of 7.4 microg/mL on ferrozine-Fe2+ complex formation.     

Profiling of phenolic compounds and antioxidant activity of dry extracts from the selected Sorbus species

The antioxidant efficiency of dry extracts from inflorescences and/or leaves of seven Sorbus species was studied using four in vitro tests of SET (single electron transfer) and HAT-type (hydrogen atom transfer) mechanisms. The 70% methanol extracts and its diethyl ether, ethyl acetate, n-butanol and water fractions were tested in parallel with the phenolic standards, e.g., caffeic acid, quercetin, BHA, BHT, and Trolox. The SET-type activity of the extracts depended primarily on the extraction solvent. The most valuable extracts were n-butanol and ethyl acetate ones, which activity was high in the DPPH (EC(50) = 3.2-5.2 μg/mL), TEAC (2.8-4.0 mmol Trolox/g), and FRAP (9.8-13.7 mmol Fe2+/g) tests, and strongly correlated with the total phenolic levels (39.6-58.2% of gallic acid equivalents). The HPLC-PDA analysis of the extracts led to the identification of chlorogenic acid, isoquercitrin, hyperoside, rutin, quercetin 3-O-sophoroside, and sexangularetin 3-O-β-D-glucopyranoside as the main components. Apart from flavonoids and hydroxycinnamic acids, proanthocyanidins have also a significant impact on the SET-type activity. The HAT-reactivity of the extracts in the linoleic acid peroxidation test (IC(50) = 36.9-228.3 μg/mL) depended more strongly on the plant tissue than on the extraction solvent, and its correlation with the phenolic content was weak. Both SET and HAT-type activity of the most potent Sorbus extracts was comparable with the activity of the standards, indicating their great potential as effective sources for health products.     

Comparative phytochemical study of methanolic and ethanolic extracts of Thymus linearis and their antibacterial and antioxidant potential

Thymus linearis (Thyme) is a medicinal plant widely distributed throughout Asia. Various parts of thyme are utilized for diverse medicinal purposes, including its use as a tonic and diuretic, for cough relief, as a flavoring agent, in treating dysentery, and for alleviating stomach disorders. Numerous studies have been conducted to explore the unexploited potential of thyme. Thyme was collected from the northern region of Pakistan, and sun-mediated extraction was conducted. Phytochemical analysis, utilizing GC–MS, revealed numerous bioactive phytochemical constituents with disease-preventing roles, including detoxifying agents, antioxidants, anticancer compounds, dietary fiber, neuropharmacological agents, and immunity-potentiating agents, in the methanolic and ethanolic (14 days) extracts of the flower, leaf, and stem. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay results indicated that the ethanolic and methanolic extracts of the stem exhibited the highest antioxidant activity, reaching up to 67.34% and 62.73%, respectively, while the values for the flower and leaf extracts (both methanol and ethanol) were around 60%. The IC₅₀ (half maximal inhibitory concentration) values were also calculated for all the samples, ranging between 7 and 9 μg/mL. Positive antibacterial and antifungal effects against Bacillus subtilis and Escherichia coli, as well as Aspergillus niger (fungi), were observed only in the extracts of the flower (both methanol and ethanol). The sun-mediated technique was used for extraction for the first time in this study. Therefore, this study introduces a novel approach to the extraction of bioactive compounds from medicinal plants, ultimately contributing to the development of herbal drugs with more convenient and cost-effective methods.     

Leishmanicidal and cytotoxic activities of extracts and naturally-occurring compounds from two Lauraceae species

The in vitro leishmanicidal effects of ethanolic extracts and fifteen naturally-occurring compounds (five lignans, eight neolignans, a diterpene and a dihydrochalcone), obtained from Pleurothyrium cinereum and Ocotea macrophylla, were evaluated on promastigotes of Leishmania panamensis and L. braziliensis. In addition, in order to determine the selective action on Leishmania species as a safety principle, in vitro cytotoxicity on J774 cells was also evaluated for test compounds and extracts. One extract and seven compounds showed activity against Leishmania parasites at different levels. Dihydroflavokawin B (8) was found to be the most potent antileishmanial compound on both parasites, whilst (+)-otobaphenol (14), was found to be the most selective compound on L. panamensis.     

Antimicrobial and antioxidant activities of a new benzamide from endophytic Streptomyces sp. YIM 67086

A new benzamide (1) and four known compounds (2–5) were isolated from endophytic Streptomyces YIM67086, and their structures were determined as 2-amino-3,4-dihydroxy-5-methoxybenzamide (1), 4-hydroxy-3-methoxybenzoic acid (2), phenylacetic acid (3), N-acetyltyramine (4) and p-hydroxytruxinic acid (5). Compound 5 was first found in the microorganism. The antimicrobial activities of compounds 1–5 and antioxidant activity of compound 1 were investigated.     

Composition,antibacterial, antioxidant and antiproliferative activities of essential oils from three Origanum species growing wild in Lebanon and Greece

The essential oils from Origanum dictamnus, Origanum libanoticum and Origanum microphyllum were analysed by GC-MS, finding carvacrol, p-cymene, linalool, γ-terpinene and terpinen-4-ol as major components. The antioxidant activity by the DPPH and FRAP tests and the antiproliferative activity against two human cancer cell lines, LoVo and HepG2, were investigated, showing that the essential oil of O. dictamnus was statistically the most inhibitory on both the cell lines, while all the oils exerted a weak antioxidant activity. Furthermore, the samples were tested against 10 Gram-negative and Gram-positive bacteria; all the oils were active on Gram-positive bacteria but O. dictamnus essential oil was the most effective (MIC = 25–50 μg/mL), showing also a good activity against the Gram-negative Escherichia coli (MIC = 50 μg/mL). Data suggest that these essential oils and particularly O. dictamnus oil could be used as valuable new flavours with functional properties for food or nutraceutical products.     

Phytochemical analysis and antimicrobial activities of methanolic extracts of leaf, stem and root from different varieties of Labisa pumila Benth

A local herb, Kacip Fatimah, is famous amongst Malay women for its uses in parturition; however, its phytochemical contents have not been fully documented. Therefore, a study was performed to evaluate the phenolics, flavonoids, and total saponin contents, and antibacterial and antifungal properties of the leaf, stem and root of three varieties of Labisia pumila Benth. Total saponins were found to be higher in the leaves of all three varieties, compared to the roots and stems. Leaves of var. pumila exhibited significantly higher total saponin content than var. alata and lanceolata, with values of 56.4, 43.6 and 42.3 mg diosgenin equivalent/g dry weight, respectively. HPLC analyses of phenolics and flavonoids in all three varieties revealed the presence of gallic acid, caffeic acid, rutin, and myricetin in all plant parts. Higher levels of flavonoids (rutin, quercitin, kaempferol) were observed in var. pumila compared with alata and lanceolata, whereas higher accumulation of phenolics (gallic acid, pyrogallol) was recorded in var. alata, followed by pumila and lanceolata. Antibacterial activities of leaf, stem and root extracts of all varieties determined against both Gram positive (Micrococcus luteus, Bacillus subtilis B145, Bacillus cereus B43, Staphylococcus aureus S1431) and Gram negative (Enterobacter aerogenes, Klebsiella pneumonia K36, Escherichia coli E256, Pseudomonas aeruginosa PI96) pathogens showed that crude methanolic extracts are active against these bacteria at low concentrations, albeit with lower antibacterial activity compared to kanamycin used as the control. Antifungal activity of methanolic extracts of all plant parts against Fusarium sp., Candida sp. and Mucor using the agar diffusion disc exhibited moderate to appreciable antifungal activities compared to streptomycin used as positive control.