TOTAL PHENOLIC CONTENT, RADICAL SCAVENGING, AND ANTIBACTERIAL ACTIVITY OF THREE DIFFERENT FRACTIONS OF PARIJOTO FRUIT (MEDINILLA SPECIOSA BLUME)

Chemical composition, phenolic content, free radical scavenging and antifungal activities of Achillea biebersteinii

Thirty-three commercial thyme honeys (Thymus spp.) were characterized and classified according to geographical origin based on quality parameters, total phenolic content and radical scavenging activity. Quality parameter analysis included the determination of: pH, free, lactonic and total acidity, electrical conductivity, moisture, ash, hydroxymethylfurfural (HMF) content and diastase activity, using official methods of analysis. Finally, total phenolic content and % radical scavenging activity (%RSA) were estimated using the Folin–Ciocalteu and the 1,1-diphenyl-2-picryl-hydrazil [DPPH·] assay, respectively. Results showed that thyme honeys analyzed: (1) met all the quality criteria set by the EU; (2) showed variations in total phenolic content and radical scavenging activity; (3) possessed a special food character since total phenolic content was positively correlated with radical scavenging activity and (4) were successfully classified (correct prediction rate 93.9%) according to geographical origin applying chemometric analyses to the data collected. Practical Applications The present study highlights quality criteria and bioactive properties of Greek commercial thyme honeys, produced in different regional departments in Greece. Such parameters determined, give an enhanced functional food character to this product which can lead to consumers' awareness on nutritional foods of specific regional origin. In addition, the use of chemometric analyses on quality parameters, total phenolic content and radical scavenging activity proved to be a strong key for correct geographical classification of Greek commercial thyme honey.

This study examined the antioxidant chemical constituents (total phenolic and total flavonoid contents) and antioxidant activities [1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) radical scavenging, and ferric reducing antioxidant power (FRAP)] of different solvent extracts of eighteen functional plants. The active components of the target plants were extracted using four different solvents (methanol, ethanol, chloroform, and water). Mentha piperascens leaf exhibited a higher total phenolic content (chloroform and water extracts), total flavonoid content (all solvent extracts), DPPH radical scavenging activity (methanol, ethanol, and water extracts), ABTS radical scavenging activity (water extract), and FRAP radical scavenging activity (water extract) (in all solvent extracts). Similarly, Petasites japonicas root was another excellent and competent extract with a high total flavonoid content (in all four solvent extracts), DPPH and ABTS radical scavenging activity (methanol, ethanol, and water extracts), and FRAP activity (methanol, ethanol, and water extracts) (in all solvent extracts). Rubus coreanus fruit had the highest total phenolic content (methanol, ethanol, and water extracts), DPPH and ABTS radical scavenging activate (in all solvent extracts), and FRAP in its water extract were the two most effective functional plants. Based on the abundance of antioxidant chemical constituents and the most potent antioxidant activity demonstrated in this study, extracts from M. piperascens leaf, P. japonicas root, and R. coreanus fruit appear to be promising candidates to meet the current demand for natural preservatives in food and pharmaceutical industries.

The hawthorn Crataegus mexicana is a traditional Mexican fruit with properties that make this fruit useful for the treatment of many ailments, including diseases of the respiratory and urinary tract. This paper reports the antioxidant capacity of the n-hexane, dichloromethane, ethyl acetate, acetone, ethanol and methanol extracts of C. mexicana. Samples were evaluated for total phenolic and carotenoid contents, 2,2-diphenyl-1-picryl-hydrazyl (DPPH) radical scavenging, the inhibition of the formation of thiobarbituric acid reactive species (TBARS) and the neutralization of the cation-radical 2,2´-azino-bis(3ethyl benzothiazoline-6-sulfonic acid) diammonium salt (ABTS). The total phenolic content was 2.65 ± 0.23 mg of gallic acid equivalents per gram, and the carotenoid content was 26.4 ± 0.02 µg/g in dry hawthorn skin. The most active extract in scavenging DPPH radicals and inhibiting TBARS formation was the acetone extract, with activities of 21.9 ± 0.15 and 13.27 ± 0.70%, respectively, at 10 mg/L. The extracts were compared for activity against ascorbic acid, caffeic acid, α- tocopherol and quercetin. The acetone extract was the most active, with an IC50 value of 15.2 mg/L in DPPH and 17.7 mg/L in TBARS. A high correlation was observed between the results for TBARS and DPPH. These results demonstrate the potential nutritional and antioxidant value of this Mexican fruit.

European elder or elderberry (Sambucus nigra L., Viburnaceae) is a plant species with known high pharmaceutical and nutritional value. However, the Greek native germplasm of S. nigra has not been adequately utilized to date as in other regions. This study evaluates the fruit antioxidant potential (total phenolic content and radical scavenging activity) of wild-growing and cultivated germplasm of Greek S. nigra. In addition, nine cultivated Greek S. nigra genotypes were evaluated regarding the effects of fertilization (conventional and organic) on fruit phytochemical and physicochemical potential (total flavonoids, ascorbic acid content, pH, total soluble solids, and total acidity), as well as on the antioxidant potential (total phenolic content and radical scavenging activity) of fruits and leaves. Additionally, an analysis of macro- and micro-elements in the leaves of the cultivated germplasm was performed. The results demonstrated comparatively higher total phenolic contents of fruits of cultivated germplasm. The genotype was the decisive factor in the fruits' phytochemical potential and leaves' total phenolic content of cultivated S. nigra germplasm. Similarly, fertilization regime effects were found to be genotype-dependent, affecting fruit phytochemical and physicochemical attributes. The trace element analysis results were similar, with genotypes varying significantly in their concentrations of macro- and micro-elements. The current work builds on previous domestication attempts for Greek S. nigra, providing new data on the phytochemical potential of this important nutraceutical species.

DOWNLOAD PDF The aim of this research was to examine the total phenolic content and radical scavenging capacity related to antioxidant potential in different fractions of methanolic extract of mangroves trees, S onneratia alba bark. Total phenolic content was determined by the Folin-Ciocalteau method. Antioxidant potential has been determined as the free radical scavenging ability using a stable radical, diphenyl-picryl-hydrazyl (DPPH). Three fractions of methanol extracts of S. alba were subjected to free radical scavenging activity in order to evaluate their antioxidant activity. The free radical scavenging activity of different fractions obtained from successive fractionation of methanol extracts with organic solvents of different polarities; hexane, chloroform, and ethyl acetate. Total phenolics content of three fraction and crude extract are 17.84 ±0.974, 156.310 ±0.703, 226.89 ±0.605, 249.56 ±0942 (GAE μg/g) respectively for hexane, chloroform, ethyl acetate, and crude extracts (methanol extract). Antioxidant assay showed that the ethyl acetate and chloroform fractions have the high activity with IC 50 10.27 μg/ml and 27.34 μg/ml, respectively, while a weak activity was showed by hexane fraction with 147 μg/ml. Linear correlation between the total antioxidant capacity of the fractions and the total phenolic contents was observed (r 2 =0.918). This data indicated that the antioxidant activity mainly due to phenolic compound contain in those fraction. The results indicate promising S.alba or the utilization as significant source of natural antioxidant. Key words: Sonneratia alba , total phenolics, radical scavenging activity, antioxidant, DPPH

Oroxylum indicum (L.) Vent. is an important medicinal plant of Bignoniaceae family, whose root bark is authentically used in many Ayurvedic preparations. The increased demand for this plant in the herbal drug market resulted in the substitution of the original plant parts with the parts of two ethno medicinal plants-Pajanelia longifolia (Willd.) K. Schum and Radermachera xylocarpa (Roxb.) K. Schum., belonging to the same family. In the present study the total polyphenol content, DPPH free radical scavenging efficiency and total antioxidant activity of the root barks of the above mentioned three plant species were evaluated and compared. The estimation of total phenolic content revealed that Oroxylum indicum has the maximum phenolic content, than the other two species. Also there was a positive correlation between the total phenolic content and radical scavenging activity. It was observed that root bark of Oroxylum idicum has the highest DPPH radical scavenging activity (IC50 value 50), followed by Radermachera xylocarpa (IC50 value 150) and Pajanelia longifolia (IC50 value 253). The total antioxidant activity was also higher for Oroxylum indicum, equivalent to 0.34 mg of ascorbic acid, when compared to the other two species. Methanol found to be the best solvent for extraction.

:Water-distilled essential oil from the leaves of Artemisia absinthium L. collected from Ardabil, north-western Iran, was investigated for enzyme inhibition, radical scavenging properties and phytochemical analysis. In this study, total phenolic content (TPC), ferrous-ion chelating (FIC), superoxide anion and nitric oxide radical scavenging and tyrosinase inhibition activity of the leaf essential oil of A. absinthium was determined. TPC of the leaf oil of A. absinthium was determined to be 168.86 ± 9.50 µg gallic acid equivalent/mg sample. The IC of ferrous-ion chelating of A. absinthium oil was 900.32 µg. Superoxide anion and nitric oxide radical scavenging activities of this oil had IC50 of 74.85 µg and 133.34 µg respectively. The IC50 of tyrosinase inhibition activity of A. absinthium oil was 4.52 mg. There was not correlation between ferrous ion chelating activity with total phenolic implying that the oil contain no chelating ligands. The effects of radical scavenging and tyrosinase inhibition tests are ascribed that the leaf oil of A. absinthium have good potential as a natural antioxidant agent.

The study investigates the antioxidant potential of commonly used vegetable oils viz., coconut (CNO), sunflower (SFO), rice bran (RBO), groundnut (GNO), sesame (SESO) and mustard oil (MO), where the oils were extracted with methanol; and these methanolic extracts were used for the antioxidant studies. Fatty acid composition by gas chromatography, physicochemical parameters such as specific gravity, refractive index, acid value, iodine value and peroxide value were also analysed. Total phenolic content (TPC) and antioxidant activities of the oils (DPPH, ABTS, superoxide and nitric oxide radical scavenging assays) were evaluated. Phenolic compounds were identified by high-pressure liquid chromatography (HPLC). Percentage TPC was highest in groundnut oil with 3.09 mg/100 g oil followed by coconut oil, rice bran oil, mustard oil, sunflower oil and sesame oil with 1.8, 0.89, 0.56, 0.49 and 0.33 mg/100 g oil, respectively. The methanolic extracts of oils showed potential antioxidant activity in terms of super oxide and nitric oxide radical scavenging activity. Practical Applications The present study indicated that vegetable oils can contribute to the dietary intake of antioxidants, depending on the processing condition. This is the first study of its kind to investigate and compare the phenolic content by HPLC and also the radical scavenging activity (DPPH, ABTS, superoxide and nitric oxide) of different oils. It was observed that the unrefined oils posses better antioxidant activity than the refined oils, which imply the importance of optimizing and/or modifying the existing steps in the vegetable oil processing to retain the polyphenolic content in vegetable oil without compromising other physicochemical parameters. The study has brought out the importance of polyphenolic compounds in vegetable oil as radical scavenging agents that could be beneficial in the management of many degenerative diseases. This may provide vegetable oils a new dimension in health management other than its traditional uses.

The objective of this study was to determine the total phenolic content, antioxidant activity, and radical scavenging effect of the seeds and seed oils of some Citrus fruits (mandarin, orange, and lemon) collected from different locations of Turkey on November in 2008 and 2009. The total phenolic content, antioxidant activity, and radical scavenging of citrus are 209.90–287.20 mg gallic acid equivalent (GAE)/kg, 1.24–2.04 mmol TE/kg, and 2.21–0.73 DPPH. IC50 of mandarin;198.40–230.40 mg GAE/kg, 1.49–1.83 mmol TE/kg, and 1.40–0.58 DPPH. IC50 of orange; 152.70–212.30 mg GAE/kg, 1.39–1.86 mmol TE/kg, and 2.35–0.66 DPPH. IC50 of lemon seeds, respectively. They are 71.12–87.00 mg GAE/kg, 0.39–1.21 mmol TE/kg, and 5.93–3.74 DPPH. IC50 of mandarin; 46.63–92.80 mg GAE/kg, 0.65–1.18 mmol TE/kg, and 8.02–2.05 DPPH. IC50 of orange; 63.41–92.51 mg GAE/kg, 0.50–1.56 mmol TE/kg, and 3.24–2.83 DPPH. IC50 of lemon seed oils, respectively. The parameter levels are found lower in Citrus seed oils then seeds. Practical Application Citrus fruits are especially rich sources of important phenolic compounds. Antioxidants are the substances that delay the beginning of the oxidation. Phenolic compounds are widely distributed in fruits and vegetables and secondary metabolites which are synthesized in plants. Citrus seeds are a potential source for nutrients. Citrus seeds are important sources of oils.

Background: The pursuit of developing effective drugs as antioxidants can be traced back to herbal ingredients, including purslane (Portulaca oleracea). The potential of purslane as a medicinal herb can be maximized by selecting the most suitable extraction method and type of solvent. Objective: To assess the levels of total phenolic compounds, total flavonoids, and radical scavenging capacity in P. oleracea obtained through various extraction methods and solvents. Methods: This study combines maceration and reflux methods with 96% ethanol, 80% ethanol, 96% methanol, and 80% methanol solvents to extract total phenolics, flavonoids, and radical scavenging activity from purslane. The folin-ciocalteu method was employed for measuring phenolic content, the AlCl3 method for flavonoid content, and the DPPH method for radical scavenging activity determination. Results: The reflux method using 80% methanol produced the highest total phenolic content, 5.15 ± 0.07 mg GAE/g DW. The maceration method using the same solvent yielded the highest total flavonoid content, 5.74 ± 0.29 mg QE/g DW. Both extraction methods showed similar radical scavenging activity, 1.10 ± 0.003 mg AAE/g DW for maceration and 1.07 ± 0.04 mg AAE/g DW for reflux. Conclusion: The extraction method and solvent significantly impact the total phenolic and flavonoid content produced by P. oleracea.

Purpose: Papaya is one of the most common fruits which has been produced in southern part of Iran for fresh consumption. Demand for fresh-cut products has increased due to the changes in consumer attitudes. However, fresh-cut papaya is prone to softening during storage. This study carried out to determine effects of calcium lactate and hot water treatments (HWT) for maintaining fresh-cut papaya quality. Research method: After preparing fresh cut cubes of papayas, the pieces were dipped in calcium lactate (CaL) or combined with HWT. Physico-chemical parameters including calcium concentration (Ca), firmness and soluble solids concentration, catalase and peroxidaseactivities, pectin methyl esterase (PME) and polygalacturonase activities (PG),total phenolic content and radical scavenging activities, and microbial growth were measured during 9 days of storage at 5 ◦C. Findings: At the end of storage, CaL treatment combined with HWT increased calcium (Ca) concentration, catalase activity, total phenolic content and radical scavenging activities (DPPH) of papaya slices, but decreased peroxidase, PG and PME activities compared to the control. In addition, these treatments reduced microbial growth compared to the control. Limitations: No limitations were encountered. Originality/Value: Both HWT with CaL showed potential for increasing markeabitity on fresh cut papaya with their generally recognized as safe status for consumers.

BackgroundBee products are gaining interest in the field of research due to their biochemical and nutritive properties. Honey bee products have been researched extensively but little has been done in regards to stingless bees. There are many species of stingless bees including Plebeina armata, which are found in the Afrotropics. They are underground nesting and produce honey, propolis, wax, pollen and bee bread. These products are known to be rich in polyphenols that comprise of flavonoids and phenolic. In our study, we analysed colorimetrically the total flavonoid, phenolic content and radical scavenging activity of honey (n = 22) and propolis (n = 25) from Bomet, Kisii and Maralal in Kenya.ResultsHoney and propolis had total flavonoid content of 12.00–22.67 mg QE/100 g and 288.15–944.76 mg QE/100 g while total phenolic content was 87.01–239.93 mg GAE/100 g and 524.14–1225.01 mg GAE/100 g, respectively. In considerations to the regions, Maralal had the highest phenolic and flavanoid content followed by Bomet and Kisii was the least. The same trend was observed in the radical scavenging activity. Except for the total flavonoid content in honey, the difference was significant (p < 0.05).ConclusionThe polyphenol content of both honey and propolis of P. armata are equally affected by geographical location as a result of different vegetation. They are good source of antioxidants, which can be utilized in diet due to their radical scavenging properties.

Linden tea from Serbia – an insight into the phenolic profile, radical scavenging and antimicrobial activities

Effect of processing on phenolic acids composition and radical scavenging capacity of barley pasta