Phytochemical profile, antioxidant, anti-inflammatory and hypoglycemic potential of hydroalcoholic extracts from Citrus medica L. cv Diamante flowers, leaves and fruits at two maturity stages

Since the past decade consumption of certain foods has been reported to have a positive effect on health. The object of the study was to determine for the first time the chemical composition and the antioxidant, anti-inflammatory and hypoglycemic potential of Citrus medica L. cv Diamante flowers, leaves and fruits (endocarp and mesocarp) at two maturity stages. Flowers and leaves were characterized by the highest total phenols and flavonoids content. A declining trend was observed during maturity of fruits for both phenols and flavonoids. The antioxidant activity evaluated by the β-carotene bleaching test showed a strong activity for flowers and endocarp of mature fruits with IC₅₀ values of 2.8 μg/mL and 3.5 μg/mL, respectively, after 30 min of incubation. Interestingly, the mature fruits endocarp (IC₅₀ value of 426.0 μg/mL) could inhibit α-amylase with an IC₅₀ value 2-fold higher than immature fruits. None of the tested extracts affected the proliferation of human skin fibroblasts 142BR. The obtained results suggest a potential use of C. medica L. cv Diamante as new valuable Citrus species with functional properties for food or nutraceutical product on the basis of high content of phytochemicals.     

Evaluation of metal concentration and antioxidant activity of three edible mushrooms from Mugla,Turkey

This study is designed for the determination of metal concentrations, antioxidant activity potentials and total phenolics of Amanita caesarea, Clitocybe geotropa and Leucoagaricus pudicus. Concentrations of four heavy metals (Pb, Cd, Cr, Ni) and five minor elements (Zn, Fe, Mn, Cu, Co) are determined. In the case of A. caesarea, Cr and Ni concentrations are found in a high level. Concentrations of the metals are found to be within safe limits for C. geotropa. In β-carotene/linoleic acid test, L. pudicus showed the highest activity potential. In DPPH system, A. caesarea showed 79.4% scavenging ability. Additionally, reducing power and chelating capacity of the mushrooms increased with concentration. The strongest super-oxide anion scavenger was A. caesarea. In the case of total phenolics, L. pudicus found to have the highest content.     

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.     

In vitro antioxidant capacities and fatty acid compositions of three Centaurea species collected from Central Anatolia region of Turkey

Antioxidant capacities of methanolic extract and fatty acid composition of three Centaurea species were investigated. The antioxidant capacity of the extracts was evaluated by different assays, including total phenolic content, phosphomolybdenum assay, free radical scavenging activity (DPPH assay), β-carotene/linoleic acid bleaching assay, iron (III) and cupric reduction assay. The findings showed that the methanolic extract of Centaurea pulchella has the strongest antioxidant capacity compared to other two Centaurea species. The order of the antioxidant properties of Centaurea species were C. pulchella > C. patula > C. tchihatcheffii. Thirty fatty acids were identified in the oils of three Centaurea species. The major fatty acids of these species were found to be linoleic acid from C. pulchella and C. tchihatcheffii, and α-linolenic acid from C. patula. The study concluded that the Centaurea species can be used as a source of natural antioxidants and essential fatty acids.     

Comparative analysis of the antioxidant and DNA protection capacities of Anadenanthera colubrina, Libidibia ferrea and Pityrocarpa moniliformis fruits

This study aimed to explore the antioxidant and DNA protection abilities of hydroalcoholic extracts from fruits of Anadenanthera colubrina (ACHE), Libidibia ferrea (LFHE) and Pityrocarpa moniliformis (PMHE). These extracts were tested by five antioxidant methods (phosphomolibdenium and reducing power assays; superoxide, hydrogen peroxide and nitric oxide scavenging) and DNA protection capacity. Total phenolic content was measured by Folin-Ciocalteu method. ACHE exhibited the highest phenolic content (578 mg/g GAE), followed by LFHE (460 mg/g GAE) and PMHE (448 mg/g GAE). In phosphomolibdenium assay, ACHE showed 24.81% of activity in relation to ascorbic acid, whereas LFHE and PMHE had 21.08% and 18.05%, respectively. These plants showed high ability to inhibit reactive species tested with IC50 values ranged from 10.66 to 14.37 μg/mL for superoxide radical; 26.05 to 45.43 μg/mL for hydrogen peroxide; 178.42 to 182.98 μg/mL for reducing power; and 199.2 to 283 μg/mL for nitric oxide. Furthermore, these extracts had capacity to break the DNA damage induced by hydroxyl radicals. The antioxidant activity of these plants is related with their higher phenolic content and show that they may be used as source of bioactive compounds, relevant to the maintenance of oxidative stability of the food matrix, cosmetics and/or pharmaceutical preparations.     

Nutritional and nutraceutical potential of rape (Brassica napus L. var. napus) and “tronchuda” cabbage (Brassica oleraceae L. var. costata) inflorescences

Two traditional cultivated vegetables highly consumed among Northern Portuguese regions were tested for their chemical composition, nutritional profile and in vitro antioxidant properties using four assays: 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals scavenging activity, reducing power, inhibition of β-carotene bleaching and inhibition of lipid peroxidation by thiobarbituric acid reactive substances (TBARS) assay. The studied varieties of two Brassica species, locally known as “grelos” (rape) and “espigos” (“tronchuda” cabbage) are nutritionally well-balanced vegetables; particularly “tronchuda” cabbage revealed the highest levels of moisture, proteins, fat, energy, β-carotene and vitamin C; rape gave the highest contents of ash, carbohydrates, sugars (including fructose, glucose, sucrose and raffinose), essential n-3 fatty acid α-linolenic acid, and the best ratios of PUFA/SFA and n-6/n-3 fatty acids, tocopherols, lycopene, chlorophylls, phenolics, flavonoids, and also the highest antioxidant properties. The health benefits associated to the antioxidant properties reinforce their contribution to a healthy and balanced diet, highlight the interest of their consumption, validate the empirical use and add new values to traditional/regional products which have been used for a long time.     

Antioxidant capacity and bioactive compounds of four Brazilian native fruits

The purpose of this study was to evaluate the bioactive compounds and antioxidant activity of extracts from araçá (Psidium cattleianum), butiá (Butia eriospatha), and pitanga (Eugenia uniflora) fruits with different flesh colors (i.e., purple, red, and orange), and blackberries (Rubus sp.; cv. Xavante and Cherokee) collected in the southern region of Brazil. The content of ascorbic acid, total carotenoids, and phenolics were determined. The profile of the phenolic compounds was assessed by high-performance liquid chromatography combined with diode array detection (HPLC-DAD). The antioxidant activity was determined using the ferric-reducing antioxidant power (FRAP) assay, 2,2-diphenyl-2-picrylhydrazyl hydrate (DPPH) assay, total reactive antioxidant potential (TRAP) assay, and total antioxidant reactivity (TAR) assay. The Xavante blackberry and purple-fleshed pitanga showed the highest total phenolic content [816.50 mg gallic acid equivalents (GAE)/100g and 799.80 mg GAE/100g, respectively]. The araçá and red-fleshed pitanga showed the highest carotenoid content (6.27 ug β-carotene/g and 5.86 ug β-carotene/g, respectively). The fruits contained several phenolic compounds such as quercetin derivatives, quercitrin, isoquercitrin, and cyanidin derivatives, which may contribute differentially to the antioxidant capacity. The highest scavenging activity in the DPPH assay was found for purple-fleshed pitanga (IC₅₀ 36.78 mg/L), blackberries [IC₅₀ 44.70 (Xavante) and IC₅₀ 78.25 mg/L (Cherokee)], and araçá (IC₅₀ 48.05 mg/L), which also showed the highest FRAP, followed by orange- and red-fleshed pitanga. Our results revealed that some fruits grown in southern Brazil such as purple-fleshed pitanga, blackberries, and araçá are rich sources of phenolic compounds and have great antioxidant activity.     

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.     

Antioxidant and Anticholinesterase Activities in Various Parts of Sonneratia caseolaris (L.)

Cork tree, (Sonneratia caseolaris L.), family Sonneratiaceae, is a typical plant in mangroves. It is widespread in tropical and subtropical tideland throughout the World. It is reported to possess many medicinal properties. For searching new pharmacological activities of Cork tree, the total phenolic contents, antioxidant activities and the electric eel acetylcholinesterase inhibitions and the kinetics of extracts of various plant parts were determined. The graphs of trolox equivalent antioxidant capacity and ferric reducing antioxidant power of all extracts showed good linearity with P-value of slopes less than 0.05. The methanol extract of calyxs by maceration method and methanol extract of stamen by soxhlet method presented moderate trolox equivalent antioxidant capacity values. For ferric reducing antioxidant power assay, all extracts gave fair to low antioxidant activities. The tacrine, stamen extract and seed extract by maceration using methanol showed noncompetitive inhibition on acetylcholinesterase activity. While, luteolin, luteolin glycoside and calyx extract and seed extract by boiling using water presented partial noncompetitive inhibition on acetylcholinesterase activity.     

Cultivar effect on the phenolic composition and antioxidant potential of stoned table olives

Stoned green table olives “alcaparras” prepared from five different cultivars (Cv. Cobrançosa, Madural, Negrinha de Freixo, Santulhana and Verdeal Transmontana) were investigated concerning their phenolic composition and antioxidant potential. From each cultivar, five independent lots were prepared. The phenolic profile was determined by HPLC/DAD at 280 nm, and antioxidant potential measured using the reducing power and scavenging effect on DPPH (2,2-diphenyl-1-picrylhydrazyl) radicals assays. Twelve phenolic compounds were identified, being hyrdoxytyrosol the most abundant one, followed by verbascoside and tyrosol. Cv. Cobrançosa and Santulhana reported higher content of phenolic compounds, with 165.76 and 163.66 mg/kg of fresh “alcaparras” table olives, respectively. Regarding antioxidant activity, Cv. Santulhana and Cobrançosa showed higher EC₅₀ values, lower than 1.40 and 0.48 mg/mL for reducing power and DPPH methods, respectively. Significant negative correlations were obtained between olive phenolics and EC₅₀ values from the antioxidant activity. The direct contact of the pulp with water, characteristic of this processing method, eliminates important hydrossoluble compounds, being the cultivar used an important determinant for the final “alcaparras” composition in terms of ingested phenolic compounds and antioxidant activity.     

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.     

Phenolic Contents and Antioxidant Properties from Aerial Parts of Achyranthes coynei Sant

Aim of the study was to evaluate antioxidant activity and total phenolic content of Achyranthes coynei; an endemic plant used in treatment of several diseases in the same lines that of Achyranthes aspera by traditional practitioners of Belgaum region. Efficiency of extraction methods was studied for aerial parts (leaves, stem, and inflorescence) extracted in methanol using continuous shaking, microwave assisted and ultra sonic extraction technique, by exposing it for different time period. Total phenolic content was measured by Folin-Ciocalteu method and antioxidant activity using 2,2’-diphenyl-1-picryl hydrazyl radical scavenging assay and ferric reducing antioxidant power assay. Extracts of A. coynei revealed highest yield of total phenolic content in continuous shaking method compared to other methods. Significantly higher amount of phenolic content (467.07±23.35 tannic acid equivalent and 360.83±18.04 caffic acid equivalent mg/100 g FW) was estimated at 360 min of continuous shaking extraction. In 2,2’-diphenyl-1-picryl hydrazyl radical scavenging assay and ferric reducing antioxidant power assay, inflorescence and leaf showed highest potential activity, respectively. Stem extracts showed lower yield of total phenolic content and antioxidant activity. Results also showed 2,2’-diphenyl-1-picryl hydrazyl radical scavenging assay had significant correlation with total phenolic content. This is first report of total phenolic content and antioxidant studies in A. coynei.     

Antioxidant,anti-microbial and antimutagenicity activities of pistachio (Pistachia vera) green hull extract

Antioxidant, anti-microbial and antimutagenicity activities of pistachio (Ahmadaghaei variety) green hull extracts (crude and purified extracts) were studied. At first, different solvents were compared for determining of the best solvent for extraction of phenolic compounds from pistachio green hull. Water and acetonitrile with 49.32 and 6.22 (mg of gallic acid equivalents/g sample) were the best and the worst solvent in the extraction of phenolic compounds, respectively. The antioxidant capacity of crude and purified extracts were assessed through ABTS assay, DPPH assay and β-carotene bleaching (BCB) method. A concentration-dependent antioxidative capacity was verified in ABTS, DPPH assays and BCB method. The anti-microbial capacity was screened against Gram positive and Gram negative bacteria, and fungi. Aqueous and purified extracts inhibited the growth of Gram positive bacteria; Bacillus cereus was the most susceptible one with MIC of 1 mg/mL and 0.5 mg/mL for the crude and purified extracts, respectively. The results of antimutagenicity test showed that phenolic compounds of pistachio green hull have antimutagenicity activity against direct mutagen of 2-nitrofluorene. The results obtained indicate that pistachio green hull may become important as a cheap and noticeable source of compounds with health protective potential and anti-microbial activity.     

Antioxidant activities of the essential oils and methanol extracts from myrtle (Myrtus communis var. italica L.) leaf,stem and flower

This study was designed to examine the chemical composition and antioxidant activity of the essential oils and methanol extracts of Myrtus communis var. italica L. leaf, stem and flower. Myrtle leaf and flower were the valuable organs for the essential oil production representing a yield of 0.61% and 0.30% (w/w), respectively. The essential oil composition of myrtle leaf and flower was characterized by high proportions of α-pinene, the main compound of monoterpene hydrocarbon class, with 58.05% for leaf and 17.53% for flower. Stem was rich in oxygenated monoterpenes, largely due to 1,8-cineole with 32.84%. The total phenol contents varied between different myrtle parts; leaf extract had higher total phenol content (33.67 mg GAE/g) than flower (15.70 mg GAE/g) and stem (11.11 mg GAE/g) extracts. Significant differences were also found in total tannin contents among different myrtle parts, representing 26.55 mg GAE/g in leaf, 11.95 mg GAE/g in flower, 3.33 mg GAE/g in stem. The highest contents of total flavonoids and condensed tannins were observed in stem (5.17 and 1.99 mg CE/g, respectively) and leaf (3 and 1.22 mg CE/g, respectively) extracts. The HPLC analysis indicated that the main phenolic class was hydrolysable tannins (gallotannins) in leaf (79.39%, 8.90 mg/g) and flower (60.00%, 3.50 mg/g) while the stem was characterized by the predominance of flavonoid class (61.38%, 1.86 mg/g) due to the high presence of catechin (36.91%, 1.12 mg/g). Antioxidant activities of the essential oil and the methanolic extract from different myrtle parts were evaluated by using DPPH radical scavenging, β-carotene-linoleic acid bleaching, reducing power and metal chelating activity assays. In all tests, methanolic extracts of different myrtle parts showed better antioxidant activity than essential oils.     

Evaluation of antioxidant activities and phenolic content of Berberis vulgaris L. and Berberis croatica Horvat

Antioxidant activities of the ethanolic extracts of roots, twigs and leaves of common barberry (Berberis vulgaris L.) and Croatian barberry (Berberis croatica Horvat) were studied. All the extracts were found to possess some radical-scavenging and antioxidant activities, as determined by scavenging effect on the DPPH free radical, reducing power and β-carotene–linoleic acid model system. With the exception of the β-carotene–linoleic acid test, antioxidant activity correlated well with the content of main plant antioxidants, phenols and flavonols, which suggests an important role of these compounds in overall antioxidant activity of investigated plant organs. The antioxidant activity varied mostly in relation to the organ, while no significant statistically differences were found between B. vulgaris and B. croatica.     

Screening for in vitro antioxidant properties and fatty acid profiles of five Centaurea L. species from Turkey flora

Centaurea species are used for the treatment of various ailments in the popular medicine in some countries. This study was designed to examine antioxidant potentials and fatty acid profiles of five Centaurea species from Turkey flora. Antioxidant properties of methanolic extracts from these species were evaluated by six different methods: phosphomolybdenum assay, free radical scavenging assay, β-carotene/linoleic acid test system, metal chelating activity, ferric and cupric reducing power. Total phenolic and flavonoid concentrations of each extract were also determined using the Folin–Ciocalteu reagent and aluminum chloride. The results of these assay showed a significant antioxidant capacity in all researched extracts. Centaurea cheirolopha extract, with the highest amount of total phenolic and flavonoids, showed the highest antioxidant activities in all assay, except for metal chelating. Fatty acid profiles of these species were examined by GC–FID and 30 fatty acids were identified. Palmitic, linoleic, oleic, and linolenic acid were detected as the main components. The results of the study indicated that the Centaurea species can be considered as a source of new natural antioxidants and unsaturated fatty acids for food, cosmetic and pharmaceutical industries.     

Total Phenolic Content,Antioxidant, and Antibacterial Activity of Rumex crispus Grown Wild in Turkey

Abstract

In the current study, we evaluated total phenolic content, antioxidant activity (by using β -carotene bleaching assay), and antibacterial activity of aqueous and methanol extracts of the aerial part of the Rumex crispus L. (Polygonaceae) naturally grown in the Eastern Anatolia region of Turkey. The aerial part of the plant had high total phenolic content (56.31 μ g/mg DW). The antioxidant activity of aqueous and methanol extracts of the aerial part of R. crispus L., BHA, and BHT were found to be 92.35%, 95.49%, 98.16%, and 96.66%, respectively. Although the antioxidant activity of the aqueous and methanol extracts of R. crispus was lower than that of the BHA and BHT, the difference between these was not statistically significant, p < 0.05. The methanol extract possessed strong antibacterial activity against Agrobacterium tumefaciens, Bacillus cereus, Bacillus subtilis, Pseudomonas corrugate, Pseudomonas syringae pv. tomato, Salmonella typhimurium, Serratia liquefaciens, Vibrio cholerae, Yersinia frederiksenii, and Yersinia pseudotuberculosis. Therefore, the aerial part of R. crispus can be used as an effective and safe source of antioxidants and antibacterial agent.     

Appraisal of in vitro and in vivo antioxidant activity potential of cornelian cherry leaves

The antioxidant activity of the 80% methanolic extract of Cornus mas L. leaves (CMM) was evaluated by various methods both in vitro and in vivo. In vitro screening tests indicated that CMM had high antioxidant activity in terms of free radical scavenging and metal reducing activity. In vivo antioxidant activity studies in normal healthy rats demonstrated that the total antioxidant capacity of liver homogenates were increased, although no changes were observed in the activities of antioxidant enzymes superoxide dismutase, catalase and glutathione peroxidase or in the level of lipid peroxidation. Studies on CCl4-treated rats also showed that CMM restored the activities of antioxidant enzymes, lowered the level of lipid peroxidation and elevated the total antioxidant capacities of both the total blood and liver homogenates of the animals. Further activity-guided fractionation studies led to the isolation of gallic acid, a well-known antioxidant, as one of the active components.     

Chemical composition,in vitro anti-microbial,antifungal and antioxidant activities of the essential oil and methanolic extract of Hymenocrater longiflorus Benth., of Iran

In this study we identified the chemical composition, anti-microbial and antioxidant effects of essential oil and methanolic extract of Hymenocrater longiflorus Benth. Totally 87 volatile compounds from the essential oil in H. longiflorus, were identified by gas chromatography–mass spectrometry (GC–MS). These compounds are mainly monoterpene hydrocarbons, sesquiterpene hydrocarbons, oxygenated monoterpenes and oxygenated sesquiterpenoids compounds. The anti-microbial and antifungal activity of plants extracts against several pathogenic microorganisms was studied by disc diffusion and minimum inhibitory concentration procedures. The results revealed that the essential oil and polar sub-fraction are effective mostly against Staphylococcus aureus, Aspergillus niger and Candida albicans. The antioxidant activity was also determined by 1,1′-diphenyl-2-picryl-hydrazyl (DPPH) free radical scavenging, β-carotene linoleic acid assay and reducing power. In addition the total phenol of essential oil (54.6 ± 1.2), polar sub-fraction (50.0 ± 1.4) and non-polar sub-fraction (64.7 ± 2.0) were determined.     

Antioxidant Studies on Ethanol Extracts from Two Selected Genera of Indian Lamiaceae

The present work is targeted to evaluate antioxidant activity of ethanol extracts from the leaves of Plectranthus mollis and Salvia officinalis belonging to family Lamiaceae using nitric oxide scavenging, hydrogen peroxide scavenging, ferric reducing antioxidant power assay and lipid peroxidation methods. The results of the study indicate that the leaf extracts of both the plants possess in vitro antioxidant activity. The higher amount of flavanoids and phenolic compounds may correspond to their greater antioxidant activity.