Composition of essential oil and antioxidant capacity of Centaurea drabifolia Sm. subsp. detonsa (Bornm.) Wagenitz, endemic to Turkey

In this study, composition of essential oil and antioxidant capacity of Centaurea drabifolia subsp. detonsa were investigated. The antioxidant capacity of the methanolic extract was evaluated by various methods including measuring the total phenolic content, total antioxidant capacity, free radical scavenging activity (DPPH assay), β-carotene/linoleic acid bleaching assay and ferric and cupric ion reducing power assay. The composition of essential oil was identified by using gas chromatography-mass spectrometry. Totally, 41 compounds were described in the essential oil. Germacrene D (44.829%) was determined as the major compound of the essential oil. The total phenolic content, total antioxidant capacity, inhibition rate of oxidation of linoleic acid, IC(50) (in DPPH assay) and EC(50) (in reducing power) value were found to be 40.454?mg?GAE/g, 100.840?mg?AAE/g, 65.639%, 39.584?μg?mL(-1) and 0.603?mg?mL(-1), respectively. The results indicated that the extract of C. drabifolia subsp. detonsa has strong antioxidant properties and this species can be used as a natural antioxidant in food processing and pharmaceutical industries.     

Ionizing radiation treatment to improve postharvest life and maintain quality of fresh guava fruit

We investigated the potential of ionizing radiation for improving physiological responses, quality, and storage time of fresh guava fruit. Ionizing radiation treatment suppressed the respiration and ethylene production rates and thus retarded the process of fruit ripening during storage. Irradiation treatment also retarded the physical and biochemical changes associated with ripening such as firmness, titratable acidity, soluble solids content, and vitamin C during storage, but for doses higher than 0.25 kGy the vitamin C content decreased. The positive effects of ionizing radiation treatment on delayed fruit ripening and other quality attributes diminished during 22 days of storage at 10 °C. Thus, a combination of ionizing radiation with low-temperature storage (10 °C) did not have much synergistic effect on storage life and quality of guava fruit. In conclusion, ionizing radiation treatment of guava fruit with 0.25 kGy dose increased the postharvest life by 3–4 days, maintained fruit quality, and reduced the decay incidence. The optimal dose (0.25 kGy) for postharvest life extension of guava fruit may be exploited to provide phytosanitary security against many insect pests including fruit flies.     

Characterization of Antioxidant Activity of Momordica Charantia Fruit by Infrared-Based Fingerprinting

Momordica charantia is widely consumed edible fruit. The food and pharmaceutical industries use it as a natural antioxidant. However, the quality control of M. charantia-based medicinal products is questionable due to the complexity of metabolites in this fruit. Hence, this study has developed a statistical model in predicting the antioxidant value through the 2, 2-diphenyl-1 picrylhydrazyl radical scavenging activity and ferric reducing antioxidant power based on infrared spectroscopy with attenuated total reflectance. This technique was reliably used for quality control. Six ethanol extracts (0, 20, 40, 60, 80, and 100% in water) of this plant’s fruit were prepared. The radical scavenging and ferric reducing antioxidant power activities were measured and the chemical profiling of the extracts was fingerprinted by infrared spectroscopy between 4,000 and 600?cm^?1 at a resolution of 4?cm^?1. Statistical analysis was developed by correlating the bioactivity and infrared spectra of each extract using orthogonal partial least square discriminant analysis. The C–N, C?O, C–O, C–H, and OH infrared signals were positively correlated with biological activity. The antioxidant activity of the fruit of M. charantia may be due to the presence of several antioxidants that work synergistically.     

Multimodal approaches of the hydroalcoholic extract of Diospyros peregrina fruits in diabetic therapy

The matured fruits of Diospyros peregrina possess significant antidiabetic activity. The present investigation was undertaken to evaluate the target of action of the hydroalcoholic extract of D. peregrina fruit in diabetic pathophysiology. The extract was tested in vitro for inhibition of glucose absorption by α-amylase inhibition assay, glucose uptake study by isolated rat hemidiaphragm method and free radical scavenging activity by DPPH method. The extract exhibited significant α-amylase inhibition (IC?? 136.5 μg mL?1), peripheral glucose utilisation and radical scavenging (IC?? 167.5 μg mL?1) activity. From the results, it may be concluded that the hydroalcoholic extract of D. peregrina fruit can counteract diabetes by multiple mechanisms, namely inhibition of carbohydrate absorption, improving peripheral glucose utilisation and antioxidant defence.     

Dereplication coupled with in vitro antioxidant assay of two flavonoid glycosides from Diospyros peregrina fruit

Diospyros peregrina is an edible seasonal fruit found in coastal West Bengal, India. The fruits have been reported to possess a significant antioxidant activity. In this study, the aim was to isolate the lead compound responsible for the above-mentioned activity. The aqueous extract of D. peregrina fruit was subjected to dereplication coupled with an in?vitro 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical scavenging assay. The n-butanol fraction of the aqueous extract of D. peregrina fruit exhibited significant antioxidant activity (IC(50), 131.10?μg?mL(-1)) as compared with the parent extract (IC(50), 285.15?μg?mL(-1)). The n-butanol fraction was subjected to silica gel column chromatographic separation coupled with a chemo-autographic study of column eluents, employing ethanolic DPPH as a spraying reagent. Two bioactive flavonoid glycosides, namely luteoline-4'-methyl-ether-7-O-glucoside and quercetin-3-O-(glucosyl)-glucoside, were identified to exhibit IC(50) values of 74.04 and 65.78?μg?mL(-1), respectively in the DPPH assay.     

CPT accumulation in the fruit and during early phases of plant development in Camptotheca acuminata Decaisne (Nyssaceae)

We describe the dynamics of camptothecin (CPT) accumulation during the early phases of plant development in Camptotheca acuminata. TLC and HPLC analyses were performed on the entire mature fruit and all of its parts and on the organs of seedlings in different developmental stages. In the mature fruit, the CPT content was relatively high (2.83 mg g(-1) DW); it was accumulated especially in the endosperm (1.82 mg g(-1) DW) and embryo (1.10 mg g(-1) DW). Regarding seedlings, CPT was present in all of the organs, at all developmental stages. In the cotyledons, content was greatest in the early developmental stages (4.23 mg g(-1) DW) and drastically decreased once the organ reached maturity (0.34 mg g(-1) DW). A similar trend was observed for the true leaves. The results suggest that CPT is translocated from the organs at an advanced developmental stage to those at an early stage.     

Comprehensive Evaluation of Antioxidant Activity of Ribes berry Fruit Species: A Chemometric Approach

Currant fruit extracts were characterized by (2,2-diphenyl-1-picrylhydrazyl) radical scavenging activity, 2,2-azinobis-3 ethyl benzothiazoline-6-sulfonic acid cation decolorization activity, total reducing power, cupric ion reducing antioxidant power, and ferric ion reducing antioxidant power (FRAP) assays to evaluate their antioxidant activity. All five antioxidant assays revealed the highest antioxidant activity to be present for the black currants. The highest concentrations of phenolics were present in the black currants (1690?±?10?mg gallic acid equivalents (GAE)/100?g fresh weight), while the lowest value was obtained in the white currants (579?±?5?mg GAE/100?g fresh weight). The correlation between the total phenolic content and antioxidant activity assays was evaluated using regression analysis. A significant positive correlation was obtained between the total phenols and the cupric ion reducing antioxidant power (r?=?0.97, p?r?=?0.93, p?相似文献   

Antioxidant Properties of Fruit and Vegetable Whey Beverages and Fruit and Vegetable Mousses

The study assesses the antioxidant activity, total phenolic content, total flavonoids content and lipophilic pigments (β-carotene, chlorophyll a, chlorophyll b) content in homemade and marketed fruit and vegetable whey beverages and fruit and vegetable mousses. All of the tests were performed using spectrophotometric methods. The highest polyphenol content was found in the homemade green whey beverage W1G (541.95 mg/100 g) and the lowest in the market green whey beverage W2G (46.18 mg/100 g). In the fruit and vegetable mousses under study, the highest content of polyphenolic compounds was determined in the red mousse R3 (76.41 mg/100 g). The highest content of flavonoids was observed in the homemade orange whey beverage W1O (63.06 mg/100 g) and in the green mousse G2 (69.80 mg/100 g). The values of the antioxidant activity of whey beverages and mousses varied depending on the composition. The highest content of β-carotene was identified in homemade orange whey beverage (4.36 mg/100 g) and in orange mousses (in range 1.10–2.24 mg/100 g), while chlorophylls a and b—in homemade green whey beverage W1G (3.00 mg/100 g and 1.31 mg/100 g respectively) and in green mousses (chlorophyll a in range 0.54 to 1.42 mg/100 g and chlorophyll b in range 0.13 to 0.32 mg/100 g).     

Synthesis and characterization of 6-O-acyl-2-O-alpha-D-glucopyranosyl-L-ascorbic acids with a branched-acyl chain

We previously reported the chemical synthesis of a series of novel monoacylated vitamin C derivatives, 6-O-acyl-2-O-alpha-D-glucopyranosyl-L-ascorbic acids (6-Acyl-AA-2G) possessing a straight-acyl chain of varying length from C(4) to C(18), as effective skin antioxidants. In this paper, we describe branched type of 6-Acyl-AA-2G derivatives (6-bAcyl-AA-2G) synthesized by use of a 2-branched-chain fatty acid anhydride as an acyl donor. The stability of 6-bAcyl-AA-2G in neutral solution was much higher than that of 6-Acyl-AA-2G, while they were susceptible to enzymatic hydrolysis for exerting vitamin C effect. These branched derivatives as well as 6-Acyl-AA-2G increased the radical scavenging activity against 1, 1-diphenyl-2-picrylhydrazyl and the lipophilicity in octanol/water-partitioning systems with increasing length of their acyl group. In addition, the 6-bAcyl-AA-2G derivative with an acyl chain of C(12), 6-bDode-AA-2G had the excellent solubility to various solvents, suggesting easy handling in cosmetic use. These characteristics of 6-bAcyl-AA-2G may be available for skin care application as an effective antioxidant.     

Antioxidant and antibacterial activities of bark extracts from Commiphora berryi and Commiphora caudata

This study investigates the in vitro antioxidant and antimicrobial activities of eight extracts obtained from the dried barks of Commiphora berryi and Commiphora caudata (Burseraceae). The radical scavenging activity was assessed by 1,1-diphenyl-2-picryl hydrazyl (DPPH) and nitric oxide assays. The methanolic extracts of C. berryi and C. caudata showed significant DPPH radical scavenging activity, with IC?? values of 26.92 and 21.16?μg?mL?1, respectively, and low radical scavenging activity against the nitric oxide assay. The antimicrobial activity of the plants was tested against the Gram-positive and Gram-negative bacteria. The ethyl acetate, chloroform and petroleum ether extracts of C. berryi showed good antibacterial activity against Pseudomonas aeruginosa, with a minimum inhibitory concentration (MIC) of 0.26?mg?mL?1, whereas the ethyl acetate and methanol extracts of C. caudata showed moderate antimicrobial activity with an MIC of more than 2.0?mg?mL?1 against P. aeruginosa compared to the petroleum ether and chloroform extracts, which showed an MIC of 1.1?mg?mL?1. The methanolic extracts of C. berryi and C. caudata also showed moderate cytotoxic activity against a human mammary carcinoma cell line (MCF-7), with values IC?? of 82.6 and 88.4?μg?mL?1, respectively.     

Antioxidant activity of aqueous methanol extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages

In this study, we evaluate the antioxidant properties of the various extracts of Protaetia brevitarsis Lewis (Coleoptera: Scarabaedia) at different growth stages. The antioxidant activities of six different extracts from larvae, pupae and imago were measured by 1,1-diphenyl-2-picrylhydrazyl (DPPH), 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) and singlet oxygen (1O? ). The larval methanol extracts (LME) and imago methanol extracts (IME) displayed the greatest effect in DPPH and ABTS radical scavenging assay, but the activity of water extracts was weaker in the all tested assays. However, LME and IME could be compared to ascorbic acid in 1O? quenching ability (the effective concentrations of 50% 1O? quenching: EC?? 0.174, 0.149 and 0.177?mg?mL?1, respectively). The antioxidant ability of the extracts to scavenge free radicals could significantly change the contents of gallic acid equivalent, an important factor based on the value of R2. The results suggest that our study may contribute to the development of new bioactive products with potential applications to reduce oxidative stress as well as play a vital role in protecting insect organisms against oxidative damage caused by undesirable conditions.     

Antioxidant activity of phenolic and flavonoid compounds in some medicinal plants of India

In this study, total phenolics, flavonoids and vitamin C content vis-a-vis antioxidant activities were assayed in leaves and stem bark of Azadirachta indica, Butea monosperma, Cassia fistula, Mangifera indica, Syzygium cumini and Tamarindus indica using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and superoxide radical scavenging method. The DPPH radical scavenging activity positively correlated with the total phenolic content in both stem bark and leaf. Superoxide radical scavenging activity increased with increasing flavonoid contents. However, the vitamin C content could not be correlated with DPPH and superoxide radical scavenging capacity.     

Quantification of water soluble vitamins in six date palm (Phoenix dactylifera L.) cultivar's fruits growing in Dubai,United Arab Emirates,through high performance liquid chromatography

In present investigation, a comparative analysis of water soluble vitamins viz., B1 (thiamine HCl), B2 (riboflavin), B3 (nicotinamide), B5 (pantothenic acid), B6 (pyridoxine HCl), B9 (folic acid), B12 (cyanocobalamin) was carried out in fruits (immature, semimature and mature) of six date palm (Phoenix dactylifera L.) cultivars (“Barhee”, “Khalasah”, “Muzati”, “Shishi”, “Zart”, “Zardai”) growing in United Arab Emirates (UAE) by high performance liquid chromatograph (HPLC). The fruits were collected at three developing stages (immature, semimature and mature). Quantitative analysis of water soluble vitamins yield showed a significant variation within the different cultivars and the developing stages of date palm fruit. Vitamin B1, B3, B5, B6 were maximum (μg/100 g f.w.) in “Shishi”, “Zardai”, “Shishi” and “Muzati” at their matured stage, however, vitamin B2, B9, B12 were detected in immature fruit of “Khalasah”, “Khalasah” and “Shishi” cultivars. The vitamin production in fruits of different date palm cultivars was, therefore, developing stage specific and cultivar dependent. The present study showed that the date palm fruit could be used for human consumption with value addition of water soluble vitamins at their specific developmental stages.     

Comparison of fatty acid profile and antioxidant potential of extracts of seven Citrus rootstock seeds

The extracts of seven Citrus rootstock seeds have been compared regarding fatty acid profile and antioxidant potential. Sour orange (Citrus aurantium L.) was found to contain the highest oil amount (34%), while the Poncirus trifoliata cultivars contained the highest percentage of unsaturated fatty acids (84-87%). In addition, the antioxidant properties of the extracts from defatted seeds have been evaluated by measuring their radical scavenging activity against 2,2'-diphenyl-1-picrylhydrazyl. The highest antioxidant activities were observed in the case of the acetone extract of sour orange and Citrumelo Swingle (76% and 75%, respectively), at a concentration of 0.17?mg?mL(-1). Moreover, the total phenolic content of the extracts, determined using the Folin-Ciocalteau reagent, was found to be correlated with the radical scavenging activity results. The acetone extracts of sour orange and Citrumelo Swingle exhibited the highest phenolic content [112.3 and 103.4?mg gallic acid equivalent?g(-1) dry sample weight, respectively].     

Microwave-assisted extraction of phenolic antioxidants from potato peels

A response surface method was used to optimize the microwave-assisted extraction parameters such as extraction time (t) (min), solvent (methanol) concentration (S) (v/v) and microwave power level (MP) for extraction of antioxidants from potato peels. Max. total phenolics content of 3.94 mg g?1 dry weight (dw) was obtained at S of 67.33%, t of 15 min and a MP of 14.67%. For ascorbic acid (1.44 mg g?1 dw), caffeic acid (1.33 mg g?1 dw), ferulic acid (0.50 mg g?1 dw) max contents were obtained at S of 100%, t of 15 min, and MP of 10%, while the max chlorogenic acid content (1.35 mg g?1 dw) was obtained at S of 100%, t of 5 min, and MP of 10%. The radical scavenging activity of the extract was evaluated by using the DPPH assay and optimum antioxidant activity was obtained at S of 100%, t of 5 min, and MP of 10%.     

Structure of dihydrochalcones and related derivatives and their scavenging and antioxidant activity against oxygen and nitrogen radical species

Quantum mechanical calculations at B3LYP/6-31G** level of theory were employed to obtain energy (E), ionization potential (IP), bond dissociation enthalpy (O-H BDE) and stabilization energies (DE(iso)) in order to infer the scavenging activity of dihydrochalcones (DHC) and structurally related compounds. Spin density calculations were also performed for the proposed antioxidant activity mechanism of 2,4,6-trihydroxyacetophenone (2,4,6-THA). The unpaired electron formed by the hydrogen abstraction from the phenolic hydroxyl group of 2,4,6-THA is localized on the phenolic oxygen at 2, 6, and 4 positions, the C? and C? carbon atoms at ortho positions, and the C? carbon atom at para position. The lowest phenolic oxygen contribution corresponded to the highest scavenging activity value. It was found that antioxidant activity depends on the presence of a hydroxyl at the C2 and C4 positions and that there is a correlation between IP and O-H BDE and peroxynitrite scavenging activity and lipid peroxidation. These results identified the pharmacophore group for DHC.     

HPLC profiling of phenolics and flavonoids of Adonidia merrillii fruits and their antioxidant and cytotoxic properties

In this study the antioxidant and cytotoxicity activity of the Adonidia merrillii fruits were investigated using different solvent polarities (methanol, ethyl acetate and water). The results showed that the total phenolic and flavonoid contents of the methanolic extract was higher compare with other extract with respective values of 17.80 ± 0.45 mg gallic acid equivalents/g dry weight (DW) and 5.43 ± 0.33 mg rutin equivalents/g DW. Beside that The RP-HPLC analyses indicated the presence of gallic acid, pyrogallol, caffeic acid, vanillic acid, syringic acid, naringin and rutin. In the DPPH, NO2 and ABTS scavenging assays, the methanolic extract exhibited higher antioxidant activity as compared to the ethyl acetate and water extracts. The extracts exhibited moderate to weak cytotoxic activity in the assays using human hepatocytes (Chang liver cells) and NIH/3T3 (fibroblasts cell) cell lines. The findings showed the Adonidia merrillii fruit extracts to possess considerable antioxidant and cytotoxicity properties. The fruit, therefore, is a potential candidate for further work to discover antioxidant and cytotoxic drugs from natural sources.     

Screening of antioxidant activity and volatile compounds composition of Chamerion angustifolium (L.) Holub ecotypes grown in Lithuania

Since biological activity of medicinal plants is dependent on cultivation area, climatic conditions, developmental stage, genetic modifications and other factors, it is important to study flora present in different growing sites and geographical zones. This study was focused on screening of antioxidant activity of C. angustifolium harvested in six different locations in Lithuania. The total contents of phenolic compounds, flavonoids and 2,2-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging activity were evaluated by spectrophotometric methods. A correlation between radical scavenging activity and total phenolic compounds content was observed (correlation coefficient 0.98). HPLC with online post-column DPPH radical scavenging reaction detection was used for the separation of extracts. Oenothein B, rutin and one unidentified compound were predominant. Volatile compounds were analysed using solid-phase microextraction coupled with gas chromatography–mass spectrometry. Based on the analysis of volatiles, all samples were classified into two chemotypes: (I) with predominant α- and β-caryophyllenes and (II) with predominant anethole.     

黄芪药渣中阿拉伯木聚糖(AX-Ⅰ-1)的提取纯化、结构分析及体外抗氧化作用

黄芪药渣经分级提取,再通过二乙氨乙基(DEAE)-纤维素52阴离子交换柱层析和Sephacryl S-400HR凝胶柱层析分离纯化,得到4个多糖组分AX-Ⅰ-1~AX-Ⅰ-4.对多糖AX-Ⅰ-1的理化性质和结构进行研究发现,AX-Ⅰ-1含有鼠李糖、阿拉伯糖、木糖、甘露糖、葡萄糖和半乳糖(摩尔比为0.006∶14.113∶8.284∶0.116∶0.468∶1),主链由阿拉伯糖和木糖通过β-(1→2),(1→3)和(1→4)苷键组成,支链由(1→4)βArap,(1→3)βGalp和(1→2)βMan组成,非还原末端由αRhap,βGclp和βGalp组成.对多糖AX-Ⅰ-1~AX-Ⅰ-4的抗氧化研究结果表明,这4个组分对羟基自由基、超氧阴离子自由基和1,1-二苯基-2-三硝基苯肼(DPPH)自由基均有一定的清除作用;当浓度为0.1 mg/m L时,多糖AX-Ⅰ-2~AX-Ⅰ-4对超氧阴离子的清除率是阳性对照维生素C(Vc)的2倍.     

Ethanolic extract of Rubia peregrina L. (Rubiaceae) inhibits haloperidol-induced catalepsy and reserpine-induced orofacial dyskinesia

In the traditional Sardinian system of medicine, Rubia peregrina L. (Rubiaceae) is reported as an aphrodisiac herb. Since the aphrodisiacs may also have antioxidant and dopaminergic activities, the aim of this study was to study the effect of ethanolic extract of aerial parts of R. peregrina for the scavenging of free DPPH radicals and the inhibition of haloperidol-induced catalepsy in mice and reserpine-induced orofacial dyskinesia in rats. The extract exhibited significant antioxidant activity in a free radical DPPH assay with IC(50)?=?55.6?μg?mL(-1), which was very close to IC(50) of ascorbic acid. The extract of R. peregrina (100 and 200?mg?kg(-1) intraperitoneally, i.p.) significantly inhibited haloperidol (1?mg?kg(-1) i.p.) - induced catalepsy in mice (p?相似文献