DPPH Radical Inhibition Research Articles

Effects of gamma radiation on cork wastewater: Antioxidant activity and toxicity

A comprehensive assessment of the toxicity and antioxidant activity of cork boiling wastewater and the effects of gamma radiation on these parameters was performed. Antioxidant activity was evaluated using different methodologies as DPPH radical scavenging activity, reducing power and inhibition of β-carotene bleaching. The results have shown that gamma radiation can induce an increase on the antioxidant activity of cork boiling wastewater. Toxicity tests were performed to access the potential added value of the irradiated wastewaters and/or minimization of the impact for discharge in the environment. Two different methods for toxicity evaluation were followed, bacterial growth inhibition test and cytotoxicity assay, in order to predict the behavior of different cells (prokaryotic and eukaryotic) in the presence of cork wastewater. Non-treated cork boiling wastewater seemed to be non-toxic for prokaryotic cells (Pseudomonas fluorescens and Bacillus subtilis) but toxic for eukaryotic cells (A549 human cells and RAW264.7 mouse cells). The gamma radiation treatment at doses of 100 kGy appeared to increase the toxicity of cork compounds for all tested cells, which could be related to a toxic effect of radiolytic products of cork compounds in the wastewaters.

Antioxidant activity improvement of identified pine nut peptides by pulsed electric field (PEF) and the mechanism exploration

This study was aimed to explore the mechanism of peptides antioxidant activity improvement treated by pulsed electric field (PEF). The pine nut (Pinus koraiensis Sieb. et Zucc) peptides were used as the experimental materials. DPPH radical inhibition and cellular antioxidant activity (CAA) were applied to evaluate the peptides antioxidant activity. Structures of PEF-treated peptides were analyzed by mid-infrared (MIR) and circular dichroism (CD) spectroscopy. Peptides were indentified including Gln-Cys-His-Lys-Pro, Gln-Cys-His-Gln-Pro, Lys-Cys-His-Gln-Pro(KCHQP), and Lys-Cys-His-Lys-Pro. KCHQP was with the strongest DPPH radical scavenging of 89.10% ± 0.20%, and CAA units of 78.40 ± 1.71. Moreover, the DPPH radical scavenging of KCHQP was significantly increased from 89.10% ± 0.20% to 93.22% ± 0.09% under the PEF treatment conditions (pulse frequency 1800 Hz, and electric field intensity 15 kV/cm). The MIR and CD spectroscopy indicated that the structure of KCHQP was not changed by PEF. However, the zeta potential was reduced from 11.6 ± 0.28 mV to 0.4 ± 0.06 mV. This study enriched the resource of antioxidant peptides with indentified amino acid sequence. It provided a way to investigate mechanism of peptides antioxidant activity improvement treated by PEF.

Synthesis of maltodextrin-grafted-cinnamic acid and evaluation on its ability to stabilize anthocyanins via microencapsulation

In this work, maltodextrin-grafted-cinnamic acid (MD-g-CA) was synthesised and used as wall material to improve the stability of purple sweet potato anthocyanins (PSPa) via microencapsualtion. MD-g-CA was prepared through esterification in a two-step convenient synthesis procedure and characterised using infra-red (IR) spectroscopy. The IR data indicated the typical ester carbonyl stretching at around 1721 cm−1. Moreover, MD-g-CA could give about 40% inhibition of DPPH radical and present excellent UV-absorption, which were notably better than that of native MD. Maltodextrin (MD) and MD-g-CA were used to prepare PSPa microcapsules by spray drying. The stability of PSPa was evaluated by UV-Vis analysis. The microcapsules produced by MD-g-CA showed a spheres-like appearance with some cracks. Storage tests revealed that the degradation rate of PSPa embedded by MD-g-CA was much lower than that of free PSPa under the same condition. Thus, MD-g-CA could be used as an effective wall material to improve stability of anthocyanins.

Effect of pulsed electric field (PEF) on structures and antioxidant activity of soybean source peptides-SHCMN

Recently, high-intensity pulsed electric field (PEF) has successfully used in improvement of antioxidant activity. Ser-His-Cys-Met-Asn (SHCMN) obtained from soybean protein was chosen to investigate the phenomenon of antioxidant activity improvement. Effects of PEF treatment on antioxidant activity of SHCMN were evaluated by DPPH radical inhibition. Nuclear magnetic resonance (NMR), mid-infrared (MIR), circular dichroism (CD) were used to analyze structures of SHCMN. Two-factor-at-a-time results show that DPPH radical inhibition of SHCMN is significantly (P<0.05) increased to 94.35±0.03% at conditions of electric field intensity of 5kV/cm, pulse frequency of 2400Hz, and retention time of 2h. In addition, MIR and NMR spectra show that the basic structure of peptides SHCMN is stable by PEF treatment. But the secondary structures (α-helix, β-turn, and random coil) can be affected and zeta potential of PEF-treated SHCNM was reduced to 0.59±0.03mV. The antioxidant activity improvement of SHCMN might result from the changes of secondary structures and zeta potential.

Characterization of Microwave Extracted Essential Oil from Taxus cuspidata Stem and Determination of Its Phenolic Content, Antioxidant and Free Radical Scavenging Activities

This study was outlined to probe chemical composition, antioxidant and free radical scavenging activities of Taxus cuspidata stem essential oil (TCEO) using different antioxidant models followed by determination of its total phenolic content. The TCEO was obtained by hydrodistillation of stem material using a microwave-assisted extraction technique. Gas chromatography-Mass spectrometry analysis of the TCEO resulted in the determination of 87 different compounds, representing 92.3% of total oil. The oil contained monoand sesquiterpene hydrocarbons, oxygenated monoand sesquiterpenes, diterpenes, phenolics, hydroxy derivatives, steroids, indole derivatives, and fatty acids as its major constituents. The TCEO showed antioxidant capacity as the inhibition of DPPH radical by 92.8%. Also the TCEO had potent inhibitory effect on nitric oxide, superoxide, and hydroxyl radicals by 80.0%, 71.7%, and 73.7%, respectively. Moreover, the TCEO displayed concentration-dependent reducing power ability and remarkable ferric ion-induced lipid peroxidation inhibitory effect in bovine brain extract. In addition, the TCEO yielded 6.5 ± 0.5 mg GAE/g sample equivalent phenolic content. These findings confirm the biological efficacy of T. cuspidata stem as a potential source of natural antioxidant.

Antioxidant Effects and Storage Stability of Yanggaeng Supplemented with Lycii Fructus Extract

The purpose of this study was to investigate the antioxidant effects and storage stability of Yanggaeng prepared with Lycii fructus extract (LY). Lycii fructus extract was added at 0 (C), 1.5 (LY1), 3.0 (LY2), 4.5 (LY3), and 6% (LY4) (w/w), and then total phenol contents, DPPH radical inhibition, ABTS radical inhibition, and physiology of microorganisms were measured. The total phenol content of LY1-LY4 was higher than that of control Yanggaeng. LY4 showed the strongest DPPH radical inhibition of 52.51%, whereas the DPPH radical inhibition of the control was the lowest. Additionally, ABTS radical inhibition increased in accordance with an increase in the concentration of Lycii fructus extract. Microbiological analysis revealed that LY1-LY4 showed lower variation in total cell count, mold, and yeast content compared to control Yanggaeng during the storage period.

Evaluation of Artichoke Bracts as a Potential Source of Bioactive Compounds, Bio-ethanol Production and Livestock Feeding

Recycling of lignocellulosic agro-industrial residues waste is the key of the environmental sustainability. So, the goal of the present study was to utilize artichoke (Cynara cardunculus L.) bracts as a potential source of bio-active compounds or as a carbon source during bio-production of ethanol and to evaluate its nutritive value for livestock feeding by using in vitro gas production technique. The chemical composition, phenolic compounds, and radicals scavenging property of extracts were determined. Silage production and acid hydrolysis on conversion of lignocellulosicartichoke was studied. Also, the acid hydrolysate of lignocellulosic components as a carbon source was investigatedduring bio-production of ethanol using Saccharomyces cerevisiae and simultaneous saccharification fermentationprocess. The obtained results revealed variation in proximate composition and mineral content among treatments of artichoke bracts used here. The blanching processing of artichoke bracts had higher total phenolic content (935.43 mg GAE /100 g DW) and 89.64% inhibition of DPPH radical with an IC50 value of 6.23 mg/ml. The highest reducing sugar content was obtained by using sulphuric acid (3%) for 20 min at 120°C. Fermentation of the hydrolysates gave the highest ethanol yield of (10.02 g/L), which corresponds to volumetric productivity of ethanol being 1.52 g /L/h with fermentation efficiency of 97.39% and biomass of 4.64 g/L after 48 hr. The results of the present study suggest that adding sugar beet molasses to the fermentation medium enhanced production of bio-ethanol (14.01g/L). The resultsalso showed that the nutritional value of the artichoke bracts is similar to that of good roughage as hay in terms of metabolizable energy (8.42 MJ/kg DM), net energy (3.15MJ/kg DM), short chain fatty acids (99.48 mM), microbial protein synthesis (76.49 g/kg) and organic matter digestibility (63.41 %).

유자 첨가 양파발효음료의 제조 및 생리활성

Onion vinegar has an undesirable flavor and taste that results from alcohol and acetic acid production from fermentation. In this study, we have used onion vinegar to develop an onion vinegar beverage with better sensory quality. The objective of this study was to determine the optimum blending ratio by using response surface methods to produce an onion vinegar beverage containing Yuza (Citrus junos Sieb ex Tanaka). The optimal formula for a fermented onion beverage was determined using a central composite design by the response surface methodology. The independent variables were obtained by regression analysis of the reaction surface of brown sugar, apple extracts and Yuza extracts. The optimum mixing ratio for onion vinegar:water:brown sugar:apple extracts:Yuza extracts was 6.0:77.6:4.9:9.2:2.3 (w/w). The actual overall acceptance was 7.08 under optimum conditions, which was close to the maximum predicted value of 6.96. The concentration of phenolic compounds, total flavonoids, and quercetin present in the onion vinegar beverage was 14.8 mg/100 g, 2.6 mg/100 g and 1.4 mg/100 g, respectively. The onion vinegar beverage showed antimicrobial activity against Staphylococcus aureus, Escherichia coli, Salmonella typhimurium and Enterobacter aerogenes. It also showed antioxidant effects, with a DPPH radical inhibition rate of 18.2% and superoxide dismutase (SOD)-like activity of 11.5%. In conclusion, the onion vinegar beverage described here seems to have nutritional value and potential biological activity.

Best practice programme in the standardisation of traditional medicines: Evaluation of an immune booster formulated by traditional healers of the Vaal Triangle, South Africa

Background: Regulation and standardization of African traditional medicines (ATM) prescribed by traditional healers in South Africa is still far from being implemented. This is despite the fact that more people are using ATM products than ever. In an effort to demonstrate that collaboration with traditional health practitioners (THPs) can yield standardized TM products, this study aimed to evaluate the immunomodulatory effects of an herbal immune booster formulated by traditional healers from the Vaal Region, South Africa. Materials and Methods: Using normal and lipopolysaccharide (LPS) stimulated human peripheral blood mononuclear cells (PBMCs) models, doses of the immune booster ranging from 1000 to 10 μg/mL were evaluated for their cytotoxicity, inflammatory cytokines and chemokines secretion, nitric oxide (NO) secretion, malondialdehyde (MDA) assay, and 1,1-diphenyl-2-picrylhydrazyl (DPPH) assay. Results: The immune booster induced a dose dependent cytotoxic effect on both normal and LPS stimulated PBMCs with higher doses showing cytotoxicity while lower dose from 100μg/mL did not show any cytotoxicity. When re-dissolved in aqueous PBS immune booster doses up to 100 μg/mL showed better DPPH radical inhibition (41%) than ascorbic acid at 40μg/mL (33%). The immune booster also decreased lipid peroxides significantly (p< 0.05) and this was comparable to ascorbic acid. There was also a significant (p< 0.05) increase in nitrite (NO) after treatment of LPS stimulated PBMCs with immune booster doses when compared to untreated samples. The immune booster stimulated inflammatory cytokines secretion in normal PBMCs (IL 1α, IL 1β, IL 6, IL 10 and TNFα while showing a decrease in IFNγ at the higher dose) while in LPS stimulated PBMCs some cytokines were decreased (IL 1α, IL 17α and at lower doses IL 10 and TNFα) and others were increased (IFNγ, TNFα and GM-CSF) depending on the dose used. In both normal and LPS stimulated PBMCs the immune booster significantly (p< 0.05) increased (MIP 1α) while causing significant (p< 0.05) decreases in IP 10 (high dose), I-TAC and MIG secretion. Conclusions: This immune booster showed potential immunostimulatory effects by increasing nitric oxide, inflammatory cytokines and chemokines secretion in both normal and LPS stimulated PBMCs. This TM also showed promising antioxidant potential in the MDA and DPPH assays. Further in vitro and animal studies are warranted.

BEST PRACTICE PROGRAMME IN THE STANDARDISATION OF TRADITIONAL MEDICINES: EVALUATION OF AN IMMUNE BOOSTER FORMULATED BY TRADITIONAL HEALERS OF THE VAAL TRIANGLE, SOUTH AFRICA

Background: Regulation and standardization of African traditional medicines (ATM) prescribed by traditional healers in South&#x0D; Africa is still far from being implemented. This is despite the fact that more people are using ATM products than ever. In an effort to&#x0D; demonstrate that collaboration with traditional health practitioners (THPs) can yield standardized TM products, this study aimed to&#x0D; evaluate the immunomodulatory effects of an herbal immune booster formulated by traditional healers from the Vaal Region, South&#x0D; Africa.&#x0D; Materials and Methods: Using normal and lipopolysaccharide (LPS) stimulated human peripheral blood mononuclear cells&#x0D; (PBMCs) models, doses of the immune booster ranging from 1000 to 10 μg/mL were evaluated for their cytotoxicity, inflammatory&#x0D; cytokines and chemokines secretion, nitric oxide (NO) secretion, malondialdehyde (MDA) assay, and 1,1-diphenyl-2-picrylhydrazyl&#x0D; (DPPH) assay.&#x0D; Results: The immune booster induced a dose dependent cytotoxic effect on both normal and LPS stimulated PBMCs with higher&#x0D; doses showing cytotoxicity while lower dose from 100μg/mL did not show any cytotoxicity. When re-dissolved in aqueous PBS&#x0D; immune booster doses up to 100 μg/mL showed better DPPH radical inhibition (41%) than ascorbic acid at 40μg/mL (33%). The&#x0D; immune booster also decreased lipid peroxides significantly (p&lt; 0.05) and this was comparable to ascorbic acid. There was also a&#x0D; significant (p&lt; 0.05) increase in nitrite (NO) after treatment of LPS stimulated PBMCs with immune booster doses when compared&#x0D; to untreated samples. The immune booster stimulated inflammatory cytokines secretion in normal PBMCs (IL 1α, IL 1β, IL 6, IL 10&#x0D; and TNFα while showing a decrease in IFNγ at the higher dose) while in LPS stimulated PBMCs some cytokines were decreased (IL&#x0D; 1α, IL 17α and at lower doses IL 10 and TNFα) and others were increased (IFNγ, TNFα and GM-CSF) depending on the dose used.&#x0D; In both normal and LPS stimulated PBMCs the immune booster significantly (p&lt; 0.05) increased (MIP 1α) while causing significant&#x0D; (p&lt; 0.05) decreases in IP 10 (high dose), I-TAC and MIG secretion.&#x0D; Conclusions: This immune booster showed potential immunostimulatory effects by increasing nitric oxide, inflammatory cytokines&#x0D; and chemokines secretion in both normal and LPS stimulated PBMCs. This TM also showed promising antioxidant potential in the&#x0D; MDA and DPPH assays. Further in vitro and animal studies are warranted.

Chemical Composition, Antioxidant and Antimicrobial Activity of Essential Oils from Organic Fennel, Parsley, and Lavender from Spain.

The aim of this work was to (i) determine the chemical composition of the essential oils of three spices widely cultivated in Spain from organic growth: Foeniculum vulgare, Petroselium crispum, and Lavandula officinalis; (ii) determine the total phenolic content; (iii) determine the antioxidant activity of the essentials oils by means of three different antioxidant tests and (iv) determine the effectiveness of these essentials oils on the inhibition of Listeria innocua CECT 910 and Pseudomonas fluorescens CECT 844. There is a great variability in the chemical composition of the essential oils. Parsley had the highest phenolic content. Overall, parsley presented the best antioxidant profile, given its highest % of inhibition of DPPH radical (64.28%) and FRAP (0.93 mmol/L Trolox), but had a pro-oxidative behavior by TBARS. Lavender essential oil showed the highest antibacterial activity against L. innocua (>13 mm of inhibition at 20–40 μL oil in the discs), followed by parsley with an inhibition zone of 10 mm (when more than 5 μL oil in the discs), and fennel 10 mm (when more than 40 μL oil in the discs). P. fluorescens was not inhibited by the tested essential oils.

Antioxidant activity, acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum extracts.

In this study several investigations and tests were performed to determine the antioxidant activity and the acetylcholinesterase and tyrosinase inhibitory potential of Pulmonaria officinalis and Centarium umbellatum aqueous extracts (10% mass) and ethanolic extracts (10% mass and 70% ethanol), respectively. Moreover, for each type of the prepared extracts of P. officinalis and of C. umbellatum the content in the biologically active compounds – polyphenols, flavones and proanthocyanidins was determined. The antioxidant activity was assessed using two methods, namely the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay and reducing power assay. The analyzed plant extracts showed a high acetylcholinesterase and tyrosinase inhibitory activity in the range of 72.24–94.24% (at the highest used dose – 3 mg/mL), 66.96% and 94.03% (at 3 mg/mL), respectively correlated with a high DPPH radical inhibition – 70.29–84.9% (at 3 mg/mL). These medicinal plants could provide a potential natural source of bioactive compounds and could be beneficial to the human health, especially in the neurodegenerative disorders and as sources of natural antioxidants in food industry.

Antiangiogenic and antioxidant properties of Calamansi Citrus microcarpa peel ethanolic extract

&lt;p&gt;Angiogenesis or the development of blood vessels and oxidation or the radical transformation of cellular substances are two key processes that contribute to cancer progression. This study evaluated the antiangiogenic and antioxidant properties of different concentrations of calamansi (Citrusmicrocarpa)ethanolic peel extract. Preliminary quantification of active compound phenolic acid in 1 ml of 0.1% extract solution revealed 0.005% phenolic acid content. By chorioallantoic membrane (CAM) assay of 11-day duck embryo, 0.10 g/ ml to 0.30 g/ml extract revealed significantly lower numbers of blood vessels compared to the untreated control (p&amp;lt;0.05), in a concentration-dependent fashion, demonstrating antiangiogenic property of the extract. On the other hand, by 1, 1-Diphenyl-2-picrylhydrazyl (DPPH) assay, 0.10% to 0.50% extract concentrations were tested against DPPH radical using ascorbic acid as positive control. Spectrophotometric analysis revealed significantly stronger inhibition of DPPH radical by the extract than by ascorbic acid (p &amp;lt; .05), demonstrating more powerful antioxidant property of the extract than ascorbic acid. Hence, the study proved that C. microcarpa peel extract exhibits both antiangiogenic and antioxidant properties. Development of anti-cancer therapy envisaged, antiangiogenic and antioxidant bioassays of the extract using tumor-positive animal models are recommended.&lt;/p&gt;&lt;p&gt;&lt;strong&gt;Keywords:&lt;/strong&gt; Pharmacology, antiangiogenic, antioxidant, CAM Assay, DPPH Assay, Citrus microcarpa, Philippines&lt;/p&gt;

Antioxidants and Antimicrobial- Activities of Methanol Leaf Extract of Senna occidentalis

Background: Oxidative stress and infectious disease have always been considered as a leading cause of morbidity and mortality in humans. Free radicals damage other molecules by extracting electrons from them in order to attain stability. The side effects associated with commonly used conventional antioxidants drugs have necessitated the search for natural antioxidants from plants extracts. Original Research Article Tsado et al.; JAMPS, 8(2): 1-7, 2016; Article no.JAMPS.25655 2 Objective: The antioxidants and antimicrobial activities of methanol leaf extract of S. occidentalis obtained from North Central, Nigeria were evaluated against some pathogenic microorganism. Methods: The antioxidants activities were conducted using DPPH radical scavenging assay. The antibacterial activities were screened against Escherichia coli, Klebsiella pneumoniae and Candida albicans, Staphylococcus aureus, Pseudimonas aeruginosa and Salmonella typhi using agar well diffusion method at various concentrations (80-360 mg/ml). The minimum inhibitory concentration (MIC) was determined using serial dilution method while minimum bacterialcidal concentration (MBC) by plating various dilution of extract. Results: The extract show significant antibacterial activities with MIC in the range of 160 mg/ml280 mg/ml and MBC in range of 160 mg/ml – 320 mg/ml. The most sensitive organisms were S. aureus and P. aeruginosa while K. pneumonia show some degree of resistances compared to other organisms tested. However, the organisms were not sensitive to the extract at the dose of 80 and 120 mg/ml. The extracts and the standard antioxidant (Vitamin E) promoted an inhibition of DPPH radical with IC50 value of the extract (263.53±3.24 mg/mL) significantly (p < 0.05) higher than 83.63±2.78 mg/mL obtained for standard drug. Conclusion: Methanol leaf extract of S. occidentalis contains some useful potential antimicrobial and antioxidant compounds that could serve as candidate for the development of drug for therapeutic purposes.

Antioxidant Activity of the Fruit and Stem Bark of Tetrapleura tetraptera Taub (Mimosaceae)

The present investigation was carried out to evaluate the antioxidant activity of ethanol extracts of Tetrapleura tetraptera stem bark and fruit. 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging assay and ferric reducing antioxidant property (FRAP) assay were carried out to determine the antioxidant activity of the extracts. The antioxidant activity of the extracts which was determined by DPPH increases with a corresponding increase in concentration. The percentage DPPH radical inhibition ability of the stem bark ranged from 28.74% to 85.26% while that of fruit ranged from -10.56% to 66.01%. The percentage antioxidant activity of the stem bark extract is almost at par with that of ascorbic acid while that of fruit extract is about 75%. But at 25 mg/ml, the fruit extract showed a pro-oxidant activity. The reductive ability of the stem bark extract ranged from 0.393 to 1.641 mg ascorbic acid equivalent per mL of extract (about two-fifth of the reference drug) while that of fruit extract ranged from 0.342 to 1.325 mg ascorbic acid equivalent/mL of extract (one-third that of reference drug). The efficacy of the fruit and stem bark extracts of T. tetraptera in some of its bioactivities may be attributed to its favourable antioxidant potential.

Antioxidant Activity of Selected Medicinal Plants of Pakistan

In the current study an effort was carried out to investigate the fruits of some selected plants with highest antioxidant potential. For this purpose ethanolic crude extracts of selected plants fruits, frequently used for various medicinal purposes in Pakistan were subjected to 2,2-diphenyl-1-picrylhydrazyl radical scavenging assay at different concentrations ranging from 100 to 500μg/ml. The results obtained revealed that the ethanolic crude extract of Juglans regia have DPPH scavenging activity of 95.42% at 500 μg/ml. This plant showed the highest DPPH scavenging capacity of all the tested plants. Elaeagnus angustifolia showed 43.90% inhibition of DPPH radical at 500 μg/ml. The ethanolic crude extract of Cydonia oblonga showed DPPH scavenging 27.18% at 500 μg/ml. The ethanolic crude extract of Morus alba showed the lowest DPPH scavenging activity (18.01%) at 500 μg/ml. The DPPH scavenging activity of ethanolic crude extract of Psidium guajava was 12.28% at 500 μg/ml, while Zizyphus jujube exhibited 19.52% inhibition of DPPH radical at the concentration level of 500 μg/ml. The DPPH scavenging activity of Phoenix dactylifera was noted as 37.98% at highest concentration. From the results obtained it is clear that the Juglans regia possess high DPPH scavenging properties. All the extracts showed maximum activities at highest concentrations. These plants needed further exploration to isolate the highly potential antioxidant compounds.

Antioxidant efficacy of carotenoid extract from bacterial strain Kocuria marina DAGII

Free radicals generation and cellular oxidation during metabolic activities often results serious cellular damage as well as life threatening diseases in human. Over the years scientific exploration has been extensively carried out to find suitable biomolecules to overcome these issues and carotenoids has that potential to confer such significant antioxidant property by means of radical scavenging and auto-oxidation inhibiting activity. The present study focuses on determination antioxidant potentiality of carotenoid from a bacterial strain, designated and identified as Kocuria marina DAGII. The antioxidant characteristics of the carotenoid was studied by measuring DPPH (2, 2-diphenyl-1-picrylhydrazyl) radical scavenging activity and inhibition of Linoleic Acid peroxidation capability. The activity of carotenoid has been studied comparatively with ß carotene and ascorbic acid as standard antioxidant and the IC 50 value has been determined. It has been found that the extracted carotenoid exhibit 76.88% radical scavenging activity with IC 50 value of 53.76μg/mL against ß carotene (146.56μg/mL) and ascorbic acid (40.43 μg/mL). Inhibition of linoleic acid per oxidation of the carotenoid has been (89.65%) with IC 50 value of 43.81μg/mL while ß carotene and ascorbic acid has shown 58.47%, 90.12% inhibition and IC 50 value of 121.40μg/mL and 38.36μg/mL respectively. Thus it can be concluded that the extracted carotenoid exhibit higher antioxidant activity in terms of DPPH radical scavenging and Linoleic acid auto oxidation inhibition capability than ß carotene that can encourage to use this carotenoid as a potential nutraceutical, food additives as well as in other industrial aspects, although it requires further studies.

Essential oils from leaves of various species: antioxidant and antibacterial properties on growth in pathogenic species

Essential oils can be employed in the food, drinks, toiletry and cosmetics industries to prevent or reduce lipid deterioration and contamination by microorganisms. The aim of this work was to evaluate the functional antimicrobial and antioxidant properties of essential oils of fresh leaves from Coniza bonariensis, Parthenium hysterophorus, Tithonia diversifolia, Ambrosia polystachya, Hedychium coronarium and Baccharis dracunculifolia, extracted by hydrodistillation. The methodologies used for assessing antioxidant potential were consumption of the DPPH radical and oxidation inhibition of the β-carotene/linoleic acid system. Sensitivity of the bacteria Salmonella cholerasuis, Listeria monocytogenes, Staphylococcus aureus and Escherichia coli to the essential oils was determined using the agar-well diffusion method. The essential oils were noteworthy for their high terpenoid content. None of the essential oils assessed by DPPH radical sequestration presented significant IC50. Using β-carotene/linoleic acid methodology, the essential oils of T. diversifolia and H. coronarium showed no significant activity, and C. bonariensis, P. hysterophorus, A. polystachya and B. dracunculifolia showed IC50 greater than the highest concentration evaluated. The essential oils of C. bonariensis, T. diversifolia, H. coronarium and B. dracunculifolia displayed antibacterial activity for gram-negative and grampositive bacteria, with the exception of the volatile oil of P. hysterophorus, which did not inhibit growth in any of the bacterial strains tested. The essential oil of A. polystachya displayed antibacterial activity only for strains of S. aureus.

Chemical composition, antibacterial and antioxidant activities of essential oil of Eucalyptus globulus from Algeria

Essential oils are known for their use in various fields such as cosmetic, pharmaceutical and food industries. The aim of this work is to investigate the chemical composition of essential oils from Eucalyptus globulus leaves (E. globulus) by gas-chromatography coupled with mass spectrometry (GC/MS) method, and to evaluate their antioxidant capacity (DPPH radical scavenging effect, reducing power, and inhibition of lipid peroxidation activity) as well as their antibacterial activity, against periodontopathogenic and cariogenic bacterial species, using microdilution method in 96-well microplates. In total, 26 compounds were identified with the predominance of oxygenated monoterpenes (78.58%); 1,8-Cineole (55.29%), Spathulenol (7.44%) and α-Terpineol (5.46%) being the main components. The analyzed oils exhibited a weak antioxidant capacity, but a marked antibacterial activity against Gram negative bacteria, mainly for F. nucleatum ATCC 25586 (MIC=1.14mg/mL) and P. gingivalis ATCC33277 (MIC=0.28mg/mL). Therefore, E. globulus essential oils may have a potential therapeutic application for the treatment of periodontal diseases.

Antibacterial action against food-borne microorganisms and antioxidant activity of carvacrol-rich oil from Lippia origanoides Kunth.

BackgroundLippia origanoides Kunth from Northeast Brazil is a plant of pleasant odor used by local people as a food seasoning in substitution the oregano where its carvacrol-rich oil has showed significant antimicrobial activity against human pathogens.MethodsGC and GC-MS analyzed the plant oil composition and its antibacterial activity was evaluated by disk diffusion and microdilution broth methods. The determination of oil antioxidant activity was made by DPPH radical scavenging assay. Oil toxicity was performed on mice.ResultsThe main constituents of the oil were carvacrol (47.2 %), thymol (12.8 %), p-cymene (9.7 %), and p-methoxythymol (7.4 %). The oil was active against the bacteria of Bacillus cereus, B. subtilis, and Salmonella typhimurium, except for Pseudomonas aeruginosa. The antioxidant activity has displayed a high dose–response (r2 = 0.92), with the inhibition of DPPH radical from 15 to 82 %, at concentrations from 5 to 50 μg/mL, and also by the β-carotene bleaching assay, which showed a high inhibition of 85.2 ± 6.8 %, corresponding to about 80 % of the inhibition of Trolox (93.4 ± 0.7 %), used as a standard. The lethal dose (LD50) of the oil was determined in 1673.84 mg mL−1.ConclusionThe results confirmed that the oil of L. origanoides could be utilized for the prevention of food bacterial growth, and as an antioxidative agent for retardation of food oxidation process. The oil has low toxicity, allowing its application in the food industry.Graphical Aerial parts of Lippia origanoides Kunth