Chemical compositions,antifungal and antioxidant activities of essential oil and various extracts of Melodorum fruticosum L. flowers

This research presents the chemical composition antifungal and antioxidant activities of essential oils and various extracts from Melodorum fruticosum flowers. The essential oil composition of M. fruticosum flowers were investigated by GC–MS with 88 identified volatile constituents. Phenyl butanone, linalool, benzyl alcohol, α-cadinol, globulol and viridiflorol were found to be the major components, respectively. The dichloromethane extract played a major role as a remarkable fungicide according to their inhibition action against all tested pathogens followed by hexane extract, essential oil and methanol extract, respectively, along with their respective MIC values ranging from 125 to 1000 μg/ml. The dichloromethane extracts were also evaluated to be superior to all extracts tested with an IC₅₀ value of 87.6 μg/ml whereas other extracts showed their IC₅₀ values ranging from 100.13 to 194.50 μg/ml.     

Antimicrobial and antioxidant activities of Russula delica Fr.

Russula delica Fr. is a well known macrofungi which is used as a food in Turkey. The ethanolic extract of R. delica exhibited antimicrobial activity against some of the tested foodborne and spoilage bacteria. The phenolic composition of R. delica ethanolic extract was analyzed by high performance liquid chromatography (HPLC). The major component in R. delica ethanolic extract was catechin (5.33 mg/L). Antioxidant activities of the ethanolic extract of R. delica was evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging and chelating ability on ferrous ions assays. Scavenging effect on DPPH radicals was 26% at 10 mg/ml and chelating effects on ferrous ions was 58% at 5 mg/ml. In addition, the amounts of total phenol content (6.23 mg/g), ascorbic acid (2.93 mg/g), β-carotene (0.11 mg/g) and lycopene (0.03 mg/g) in the macrofungi ethanolic extract were determined.     

Antioxidant and antimicrobial properties of Teucrium arduini L. (Lamiaceae) flower and leaf infusions (Teucrium arduini L. antioxidant capacity)

Antioxidant and antimicrobial activities, as well as total phenol (TP, Folin–Ciocalteu method) and phenolic acid (UPLC–MS/MS) contents of leaf and flower infusions of Teucrium arduini L. from six different mountainous localities in Croatia (U?ka, Vošac, Sveti Jure, Snje?nica, Vaganac, Šušanj) were analysed in this study. Antioxidant capacity was evaluated using the ferric reducing/antioxidant power (FRAP) assay, as well as 2,2-diphenyl-1-picrylhydrazyl (DPPH), and 2,2′-azinobis (3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging assays. The antioxidant potency composite index (ACI), giving equal weight to all three methods used to quantify antioxidant capacity, was the highest for the sample from Vošac (96.7) among flower infusions, while maximum ACI (100) was determined for the infusion from U?ka among leaf infusions. Strong positive correlation was found between the total phenols and ACI for leaf (r = 0.953) and flower (r = 0.977) infusions. Our results point to significantly (p < 0.05) different TP content between leaf and flower infusions, as well as across localities. Leaf infusions of T. arduini from Šušanj exhibited marked antibacterial activity against Staphylococcus aureus, while none of the tested infusions exhibited antimicrobial activity against gram-negative bacterial species, or the tested fungal species.     

Essential oil composition and antioxidant activities of Curcuma aromatica Salisb.

The chemical composition of the hydro-distilled essential oil from leaves of Curcuma aromatica Salisb. was analysed by GC–MS. Twenty-three compounds representing 94.29% of the total oil were identified. The antioxidant activities of the oil and various extracts of C. aromatica were evaluated by using 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical-scavenging assays. The oil and methanol extract showed potent DPPH radical-scavenging activities (IC₅₀ = 14.45 and 16.58 μg/ml, respectively), which were higher than butylated hydroxyanisole (IC₅₀ = 18.27 μg/ml). The extracts also exhibited remarkable superoxide radical-scavenging activities (IC₅₀ = 22.6–45.27 μg/ml) and the activity in the methanol extract was superior to all other extracts (IC₅₀ = 22.6 μg/ml). Furthermore, the amount of total phenolic compounds was determined and its content in ethyl acetate extract was the highest as compared to other extracts. The results indicate that the oil and extracts of C. aromatica could serve as an important bio-resource of antioxidants for using in the food industries.     

Essential oils composition in two Rosmarinus officinalis L. varieties and incidence for antimicrobial and antioxidant activities

The essential oil composition of Rosmarinus officinalis var. typicus and var. troglodytorum endemic to Tunisia, and growing wild in different bioclimates, was determined by GC and GC–MS. Oils were assessed for their antimicrobial and antioxidant activity. A variation of the chemical composition attributed to varieties rather than to bioclimates was revealed. 1.8-Cineole (47.2–27.5%) and camphor (12.9–27.9%) were identified as the main constituents of var. typicus and var. troglodytorum, respectively. The principal component analysis performed on oil constituents for all the populations allowed the distinction of two distinct population groups in accordance to the varietal subdivision. Based on the determination of the diameter of inhibition and the determination of the minimum inhibitory concentration, a low to moderate antimicrobial activity according to oils was revealed against eight bacteria tested. However, oils from var. troglodytorum showed higher bactericidal effect than those from var. typicus. The oils’ antioxidant activity, determined by 1,1-diphenyl-1-picrylhydrazyl (DPPH) assay, ferric reducing (FRAP) assay and β-carotene bleaching test, was relatively high. The highest activity was found in oils from var. troglodytorum and in one population of var. typicus from the upper semi-arid bioclimate.     

Bioactive properties and chemical composition of six walnut (Juglans regia L.) cultivars

The chemical composition, antioxidant potential and antimicrobial activity were studied in six walnuts (Juglans regia L.) cultivars (cv. Franquette, Lara, Marbot, Mayette, Mellanaise and Parisienne) produced in Portugal. Concerning their chemical composition the main constituent of fruits was fat ranging from 78.83% to 82.14%, being the nutritional value around 720 kcal per 100 g of fruits. Linoleic acid was the major fatty acid reaching the maximum value of 60.30% (cv. Lara) followed by oleic, linolenic and palmitic acids. The aqueous extracts of walnut cultivars were investigated by the reducing power assay, the scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and β-carotene linoleate model system. All the walnut extracts exhibited antioxidant capacity in a concentration-dependent manner being the lowest EC₅₀ values obtained with extracts of cv. Parisienne. Their antimicrobial capacity was also checked against gram positive (Bacillus cereus, Bacillus subtilis, Staphylococcus aureus) and gram negative bacteria (Pseudomonas aeruginosa, Escherichia coli, Klebsiella pneumoniae) and fungi (Candida albicans, Cryptococcus neoformans), revealing activity against the different tested microorganisms.     

Total phenols, antioxidant potential and antimicrobial activity of walnut (Juglans regia L.) green husks

The total phenols content and antioxidant and antimicrobial activities were studied in walnut (Juglans regia L.) green husks aqueous extracts of five different cultivars (Franquette, Mayette, Marbot, Mellanaise and Parisienne). Total phenols content was determined by colorimetric assay and their amount ranged from 32.61 mg/g of GAE (cv. Mellanaise) to 74.08 mg/g of GAE t (cv. Franquette). The antioxidant capacity of aqueous extracts was assessed through reducing power assay, scavenging effects on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals and beta-carotene linoleate model system. A concentration-dependent antioxidative capacity was verified in reducing power and DPPH assays, with EC50 values lower than 1 mg/mL for all the tested extracts. The antimicrobial capacity was screened against Gram positive and Gram negative bacteria, and fungi. All the extracts inhibited the growth of Gram positive bacteria, being Staphylococcus aureus the most susceptible one with MIC of 0.1 mg/mL for all the extracts. The results obtained indicate that walnut green husks may become important in the obtainment of a noticeable source of compounds with health protective potential and antimicrobial activity.     

In vitro antioxidant,antidiabetic and antilipidemic activities of Symplocos cochinchinensis (Lour.) S. Moore bark

Symplocos cochinchinesis is used in Indian system of traditional medicine to treat diabetes mellitus. The present study investigates the in vitro antioxidant, antidiabetic and antilipidemic activities of S. cochinchinensis bark methanolic extract (SCBe) in streptozotocin (STZ) induced diabetic rats. In in vitro studies SCBe showed very good scavenging activity on 2,2-diphenyl-picrylhydrazyl (DPPH) (IC₅₀ 820.34 ± 1.74 μg/ml), hydroxyl (IC₅₀ 884.19 ± 0.45 μg/ml) and nitric oxide (IC₅₀ 860.21 ± 1.18 μg/ml) radicals, as well as high reducing power. SCBe (250 and 500 mg/kg) was administered to STZ (40 mg/kg) induced diabetic rats for 28 days. SCBe showed a significant decrease in blood glucose and significant increase in plasma insulin and liver glycogen levels in treated diabetic rats. Further, SCBe showed antilipidemic activity as evidenced by significant decrease in serum TC, TG, LDL-C levels and significant increase in HDL-C level in treated diabetic rats. SCBe also restored the altered plasma enzymes (SGOT, SGPT and ALP), total protein, urea and creatinine levels to near normal. The action of SCBe was comparable to the antidiabetic drug glibenclamide. Results of this experimental study indicated that SCBe possessed antioxidant, antidiabetic and antilipidemic activities.     

Ficus carica L.: Metabolic and biological screening

Ficus carica L. is one of the earliest cultivated fruit trees. In this work, metabolite profiling was performed on the leaves, pulps and peels of two Portuguese white varieties of F. carica (Pingo de Mel and Branca Tradicional). Phenolics and organic acids profiles were determined by HPLC/DAD and HPLC/UV, respectively. All samples presented a similar phenolic profile composed by 3-O- and 5-O-caffeoylquinic acids, ferulic acid, quercetin-3-O-glucoside, quercetin-3-O-rutinoside, psoralen and bergapten. 3-O-Caffeoylquinic acid and quercetin-3-O-glucoside are described for the first time in this species. Leaves’ organic acids profile presented oxalic, citric, malic, quinic, shikimic and fumaric acids, while in pulps and peels quinic acid was absent. The antioxidant potential of the different plant parts was checked. All materials exhibited activity against DPPH and nitric oxide radicals in a concentration-dependent way. However, only the leaves presented capacity to scavenge superoxide radical. Leaves were always the most effective part, which seems to be related with phenolics compounds. Additionally, acetylcholinesterase inhibitory capacity was evaluated, but no effect was observed. Antimicrobial potential was also assessed against several bacterial species, although no activity was noticed. This is the first study comparing the chemical composition and biological potential of F. carica pulps, peels and leaves.     

Potential analgesic,anti-inflammatory and antioxidant activities of hydroalcoholic extract of Areca catechu L. nut

The hydroalcoholic extract of Areca catechu L. (ANE) nut was screened for its analgesic, anti-inflammatory and in vitro antioxidant potential. Three doses of ANE (250, 500 and 1000 mg/kg orally) were tested for analgesic and anti-inflammatory activities. Evaluation of analgesic activity of ANE was performed using hot plate and formalin test in mice. ANE showed maximum increase in hot plate reaction time (56.27%, p < 0.01), while reduced the duration of licking/biting behaviors in first (39.45%, p < 0.05) and second (92.71%, p < 0.01) phases of the formalin test indicating significant analgesic activity. ANE reduced the paw edema considerably (86.79% inhibition after 24 h, p < 0.01) in dose-dependent manner compared to carrageenan-induced rat. In addition, in vitro antioxidant activity of ANE was investigated by total phenolic content (TPC) and hydrogen peroxide assay. The IC₅₀ observed in hydrogen peroxide assay was 83.14 μg/ml and TPC 120.56 ± 21.09 mg QE/g. Altogether, these results suggest that the hydroalcoholic extract of Areca catechu could be considered as a potential analgesic, anti-inflammatory and antioxidant agent.     

Comparative antihemolytic and radical scavenging activities of strawberry tree (Arbutus unedo L.) leaf and fruit

The present study reports the antioxidant properties of Arbutus unedo L. leaf and fruit extracts using different in vitro assays including (i) reducing power, (ii) scavenging effect on DPPH free radicals, and (iii) inhibitory effect on AAPH-induced hemolysis and lipid peroxidation in human erythrocytes. All assays demonstrated antioxidant efficiency for A. unedo L. aqueous extracts, being consistently higher in the leaf. EC₅₀ values for reducing power and DPPH radical scavenging activities were, respectively, 0.318 ± 0.007 and 0.087 ± 0.007 mg/mL for leaf, and 2.894 ± 0.049 and 0.790 ± 0.016 mg/mL for fruit extracts. Under the oxidative action of AAPH, A. unedo leaf and fruit extracts protected the erythrocyte membrane from hemolysis (IC₅₀ of 0.062 ± 0.002 and 0.430 ± 0.091 mg/mL, respectively) and decreased the levels of malondialdehyde, a breakdown product of lipid peroxidation (IC₅₀ of 0.075 ± 0.014 and 0.732 ± 0.452 mg/mL, respectively). In accordance with antioxidant activity, phenolic content was found to be significantly higher in leaf extract. To our knowledge, this is the first time that the antioxidant activity of A. unedo species is evaluated using human biological membranes. Overall, our results suggest that A. unedo leaves are a promising source of natural antioxidants with potential application in diseases mediated by free radicals.     

Acetylcholinesterase,butyrylcholinesterase, and tyrosinase inhibition studies and antioxidant activities of 33 Scutellaria L. taxa from Turkey

The members of Scutellaria L. (Lamiaceae) is known to be rich particularly in flavonoids and among them, S. baicalensis has been recorded to be used for memory-enhancing purpose. Therefore, we initiated a study to screen the methanol extracts prepared from the aerial parts of 33 Turkish Scutellaria species for their acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory activities, which are the key enzymes taking place in pathogenesis of Alzheimer’s disease. Besides, the methanol extracts were tested in vitro against another enzyme, tyrosinase, which is associated with melanin hyperpigmentation. 2,2-Diphenyl-1-picrylhydrazyl (DPPH) radical scavenger effect, ferrous ion-chelating ability, and ferric-reducing antioxidant power (FRAP) of the ethyl acetate and methanol extracts were also determined. AChE, BChE, and tyrosinase inhibition of the extracts were performed on ELISA microplate reader by spectrophotometric method. The extracts showed weak inhibition against AChE and BChE, while the best tyrosinase inhibition was caused by the methanol extract of S. brevibracteata subsp. subvelutina. The extracts had a very high DDPH radical scavenging effect and moderate antioxidant activity in ferrous ion-chelating and FRAP tests.     

A comparative study on the in vitro antioxidant potentials of three edible fruits: Cornelian cherry,Japanese persimmon and cherry laurel

This study was designed in order to investigate in vitro antioxidant potentials of 80% methanolic extracts prepared from three edible fruits, Cornus mas L., Diospyros kaki L., Laurocerasus officinalis Roem. For this purpose, 8 different tests were performed including 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging tests, ferric reducing antioxidant power (FRAP), cupric reducing antioxidant capacity (CUPRAC), metal-chelating capacity, determination of total antioxidant capacity, β-carotene bleaching test in a linoleic acid emulsion system and trolox equivalent antioxidant capacity. In addition, for evaluating the phenolic profile, total phenolic, flavonoid and proanthocyanidin contents were measured spectrophotometrically. Among the three fruits analyzed, Diospyros kaki L. showed the highest activity in all tests, except β-carotene bleaching test. Whereas, neither of three fruits showed metal-chelating activity. Also, a good correlation was found between the phenolic content and antioxidant parameters.     

Chemical composition,antibacterial and antioxidant activities of leaf essential oil and extracts of Metasequioa glyptostroboides Miki ex Hu

The aims of this study were to analyze the chemical composition of leaf essential oil of Metasequioa glyptostroboides Miki, and to test the efficacy of oil and extracts (hexane, chloroform, ethyl acetate and methanol) against food spoilage and food-borne pathogenic bacteria and their antioxidant activity. The GC–MS analysis revealed 49 compounds representing 94.62% of the total oil containing 2-butaneone (30.6%), cyclopentane (15.1%), β-myrcene (13.29%), cyclobutane (7.67%), furan (3%), valeramide (2.81%), borneol (1.2%), β-farnesene (1.67%), thymol (1.44%) and α-pinene (1.46%) as major components. The oil (1000 μg/disc), and extracts (1500 μg/disc) exhibited promising antibacterial effect as a diameter of zones of inhibition (10–18 and 7–13 mm), respectively. MIC values of oil and the extracts were ranged 125–2000 and 250 to <2000 μg/ml, respectively. Also the oil had strong antibacterial effect on the viable counts. Scanning electron microscopic study demonstrated potential detrimental effect of the oil on the morphology of S. aureus KCTC1916. The free radical scavenging activities of the oil and ethyl acetate extract were found to be 11.32 and 19.12 μg/ml, respectively. Also the ethyl acetate extract revealed the highest phenolic contents (85.17 mg/g of dry wt) as compared to the other extracts.     

Chemical composition and antioxidant activities of the essential oil and methanol extracts of Psammogeton canescens

This study is outlined to probe the chemical composition of essential oil and in vitro antioxidant activity of the essential oil and methanol extracts of Psammogeton canescens. The chemical composition of the hydrodistilled essential oil of the aerial parts of P. canescens was analyzed by GC and GC/MS. The main constituents of the oil were found to be β-bisabolene (33.35%), apiole (28.34%), α-pinene (11.86%) and dill apiole (8.17%). Antioxidant activities of the samples were determined by three various testing systems namely DPPH, β-carotene/linoleic acid, and reducing power assay. In DPPH system, the highest radical-scavenging activity was seen by the polar subfraction of methanol extract (49.5 ± 1.21 μg/ml). Furthermore, in the second case the inhibition capacity (%) of the polar subfraction (92.40% ± 0.72) found to be the stronger one. However, in the reducing power assay, a reverse activity pattern more than in the first two systems was observed, and the essential oil was stronger radical reducer than was the methanol extract in all of the concentration tested. Our findings demonstrate that the essential oil and methanol extracts of P. canescens possess significant antioxidant activities and may be suggested as a new potential source of natural antioxidant.     

Metabolic profiling and biological capacity of Pieris brassicae fed with kale (Brassica oleracea L. var. acephala)

Phenolic and organic acid profiles of aqueous extracts from Pieris brassicae material and the host kale (Brassica oleracea L. var. acephala) leaves were determined by HPLC/UV–DAD/MSⁿ-ESI and HPLC–UV, respectively. The identified phenolics included acylated and nonacylated flavonoid glycosides, hydroxycinnamic acyl gentiobiosides, and sulphate phenolics. Kale exhibited the highest content (11 g/kg lyophilized extract), while no phenolics were identified in the butterflies or exuviae. Nine different organic acids were characterized in the materials, with kale showing the highest amount (112 g/kg lyophilized extract). With the exception of the exuviae extract, the rest were screened for bioactivity. Using spectrophotometric microassays, all exhibited antiradical capacity against DPPH and NO in a concentration-dependent way, whereas only kale and excrement extracts were active against superoxide. All displayed activity on intestinal smooth muscle, albeit with distinct relaxation–contraction profiles. Larvae and butterfly extracts were more efficacious for intestinal relaxation than was kale extract, whereas excrement extract evoked only contractions, thus evidencing their different compositions. Collectively, these results show that P. brassicae sequesters and metabolizes kale’s phenolic compounds. Moreover, the extract’s bioactivities suggest that they may constitute an interesting source of bioactive compounds whose complex chemical structures preclude either synthesis or isolation.     

In vitro protective effects of Thymus quinquecostatus Celak extracts on t-BHP-induced cell damage through antioxidant activity

The purpose of this study was to evaluate the antioxidative activities of water and 70% ethanolic extracts from the Thymus quinquecostatus Celak (TQC) for natural antioxidant source. The antioxidant activities were compared with other natural and synthetic antioxidants. The levels of total polyphenols and flavonoids were also determined. The extracts were found to have different levels of antioxidant properties in a few kind of assay. The results showed that higher radical scavenging activity, reducing power and antioxidant capacity in FRAP than those of BHT as a positive control. In addition, the extracts from the TQC leaf and stem showed stronger antioxidant activity than that of vitamin C, α-tocopherol in ferric thiocyanate (FTC) and thiobarbituric acid (TBA) methods. Cytoprotective and anti-apoptotic effect of water extracts from TQC was also prevented t-BHP-induced toxicity in Chang liver cells. Therefore, these results indicate that TQC extracts have antioxidant properties through its ability to enhance the cell viability, reduction of production of ROS, inhibition of oxidative damage, mitochondria dysfunction and ultimately inhibition of cell apoptosis. Based on the results described above, it is suggested that TQC has the potential to protect liver on t-BHP-induced cell damage and should be considered as a prospective functional food.     

Extracts of Halenia elliptica exhibit antioxidant properties in vitro and in vivo

The antioxidant properties of different extracts of Halenia elliptica was investigated by employing various established in vitro systems. The results showed that various extracts possessed strong antioxidant activity in vitro, and the 70% methanol extract (ME) had the strongest antioxidant activity. Based on our in vitro results, ME was used for investigating the antioxidant properties of H. ellipticain vivo. The liver and kidney of CCl₄-intoxicated animals exhibited a significant decrease in superoxide dismutase (SOD), catalase (CAT) and glutathione (GSH) levels. Additionally, these organs exhibited a significant increase in the level of malondialdehyde (MDA). These changes were significantly reversed, in a dose-dependent manner, after treatment with ME and the standard treatment Vitamin E. Thus, it may be concluded that the ME possesses potent antioxidant properties, and might be valuable natural source of antioxidants that could be applicable to both the medical and food industries.     

Insights into cholinesterase inhibitory and antioxidant activities of five Juniperus species

In vitro acetylcholinesterase (AChE) and butyrylcholinesterase (BChE) inhibitory and antioxidant activities of the aqueous and ethanol extracts of the leaves, ripe fruits, and unripe fruits of Juniperus communis ssp. nana, Juniperus oxycedrus ssp. oxycedrus, Juniperus sabina, Juniperus foetidissima, and Juniperus excelsa were investigated in the present study. Cholinesterase inhibition of the extracts was screened using ELISA microplate reader. Antioxidant activity of the extracts was tested by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging, ferrous ion-chelating, and ferric-reducing antioxidant power (FRAP) assays. Total phenol and flavonoid contents of the extracts were determined spectrophotometrically. The extracts had low or no inhibition towards AChE, whereas the leaf aqueous extract of J. foetidissima showed the highest BChE inhibition (93.94 ± 0.01%). The leaf extracts usually exerted higher antioxidant activity. We herein describe the first study on anticholinesterase and antioxidant activity by the methods of ferrous ion-chelating, superoxide radical scavenging, and ferric-reducing antioxidant power (FRAP) assays of the mentioned Juniperus species.     

New antibacterial and cytotoxic activities of falcarindiol isolated in Crithmum maritimum L. leaf extract

Bioassay-guided fractionation of a chloroformic extract obtained from Crithmum maritimum leaves led to the chemical isolation of falcarindiol, a polyacetylene widely distributed within the Apiaceae family. Structure of this compound was confirmed by NMR and activity was tracked using a screening microplate bioassay. Falcarindiol strongly inhibited the growth of Micrococcus luteus and Bacillus cereus, with a minimum inhibitory concentration (MIC) value of 50 μg ml⁻¹. Moreover, this compound showed cytotoxicity against IEC-6 cells with an IC₅₀ value of 20 μM after 48 h of exposition. These results suggest that Crithmum maritimum could be potentially used in food manufactures and cosmetology as preservative agents and biopesticides, or in medicine as new antibiotics, confirming the interest in studying halophytic species as sources of bioactive compounds.