Effect of dietary oregano (Origanum vulgare L.) essential oil on growth performance, cecal microflora and serum antioxidant activity of broiler chickens

A feeding trial was conducted to investigate the effects of dietary oregano (Origanum vulgare L.) essential oil (OEO) on broiler performance, cecal microflora and serum antioxidant activity. One hundred and eighty (180) 1-day old broiler chicks were randomly divided into four groups. Group I was kept as normal control and received basal diet. Birds of groups II, III and IV were treated with basal diet supplemented with 300, 600 and 1200 mg/kg of OEO. Inclusion of 600 mg/kg of OEO in grower diet significantly increased body weight gain when compared with the control group (P < 0.05). Supplementation of 600 and 1200 mg/kg of OEO significantly improved feed conversion ratio compared with the control group in grower and overall experimental periods (P < 0.05). Although, populations of lactic acid bacteria remained unaffected (P > 0.05), populations of cecal Escherichia coli were significantly lower in 300 and 600 mg/kg OEO supplemented groups in comparison with the control and 1200 mg/kg OEO supplemented groups (P < 0.05). Although, serum antioxidant activity was not significantly affected by the treatments (P > 0.05), antioxidant activity of serum was higher in OEO supplemented groups. In conclusion, OEO exerted growth promoting effects and also displayed potent antibacterial effects against cecal E. coli.Key words: Oregano essential oil, performance, cecal microflora, antioxidant activity

Nitric oxide radical scavenging potential of some Elburz medicinal plants

Some plants scavenge nitric oxide (NO) with high affinity. For this purpose, forty extracts from 26 medicinal plants, growing extensively in Elburz mountains, were evaluated for their NO scavenging activity. Total phenolic and flavonoid contents of these extracts were also measured by Folin Ciocalteu and AlCl3 colorimetric assays, respectively. Sambucus ebulus fruit aqueous extract and Pterocarya fraxinifolia leaf methanol extract showed better activity than others with IC50 equal to 29 and 65 g ml-1, respectively. NO is also implicated in inflammation and other pathological conditions, therefore very powerful scavenging activity of S. ebulus fruit extract may explain its very good anti-inflammatory activity. Phenolic and flavonoids contents of the extracts varied between 10.2 - 200.4 and 2.1 - 90.9 mg g-1 of extract, respectively. Good correlations could be found between total phenolic contents and NO scavenging activity through linear regression analysis (R2 = 0.63). There was also a better correlation between total flavonoids and NO scavenging activity (R2 = 0.73). High NO scavenging activity in plants can candidate them for testing their anti-inflammatory property.Key words: Antiinflammatory, flavonoid contents, medicinal plants, nitric oxide scavenging activity, phenolic contents, Sambucus ebulus, Pterocarya fraxinifolia

Effect of Extract of Aerial Parts of Urtica dioica (Urticaceae) on the Stability of Soybean Oil

Purpose: To evaluate the effectiveness of Urtica dioica (Urticaceae) extract as a natural antioxidant and compare with the most commonly used synthetic antioxidants, butylated hydroxyanisole (BHA) and butylated hydroxytoluene (BHT).Methods: Three different U. dioica extracts, viz, chloroform, methanol (80 %) and water extracts, were prepared. The antioxidant activity of the extracts were evaluated by 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical scavenging and soybean oil models. Varying concentrations of the extracts (200, 500 and 800 ppm), BHA and BHT (100 and 200 ppm) were separately added to soybean oil and stored in the oven (60±1 °C) for 25 days. Peroxide and thiobarbituric acid (TBA) values were measured at various heating periods for the oil samples. Total phenolic and flavonoid contents of the extracts were determined using Folin–Ciocalteu and aluminium chloride methods, respectively, while the aerial parts of the plant were also phytochemically screened.Results: Analysis of the chemical composition of U. dioica aerial parts showed they contain crude proteins (21.78 %±0.11), crude lipids (1.66 %±0.03), total soluble carbohydrates (37.19 %±0.21), crude fibers (19.62 %±0.14) and ash (19.75 %±0.17). The aqueous extract contained the highest level of total phenolic contents (7.89 ±0.38, mg g-1 of powder) while the choroform extract contained the highest level of flavonoid contents (15.40 ±0.53 mg g-1 powder). The half-maximal concentration (IC50) values for chloroform, methanol (80 %) and aqueous extracts in respect of DPPH radical scavenging activity were 77.53±0.99, 199.71±1.02 and 159.88±1.57 μg ml-1, respectively. Mixing soybean oil with 200 - 800 ppm of extract decreased oil oxidation and formation rate of TBA reacting substances at a level that is almost equivalent to the synthetic antioxidant, BHT, at a concentration of 200 ppm.Conclusion: These findings demonstrate that mixing soybean oil with U. dioica extract can improve the quality of the oil during frying process.Keywords: Antioxidant activity; Soybean oil; DPPH; Peroxide value; Thiobarbituric acid value; Urtica dioic

Antioxidant Activity of the Bulb and Aerial Parts of Ornithogalum sintenisii L (Liliaceae) at Flowering Stage

Purpose: Ornithogalum sintenisii is an Iranian species with little known about its pharmacological effects. The purpose of the present study was to investigate some antioxidant properties of the plant.                    Methods: The antioxidant potency of the freeze-dried methanol extract of O. sintenisii bulbs and aerial parts were investigated by evaluating the following parameters: linoleic acid peroxidation, 1,1-diphenyl-2-picryl hydrazyl radical (DPPH), scavenging of nitric oxide and hydrogen peroxide as well as reducing power and Fe2+ chelating activity, using standard methods. Phenol and flavonoid contents were determined as gallic acid and quercetin equivalents, respectively.Results: The aerial parts contained higher phenol and flavonoid contents than the bulbs. IC50 for DPPH radical-scavenging activity was 368 ± 15 and 669 ± 25 μg ml-1 for aerial parts and bulbs, respectively. The reducing power of the extracts was less than that of vitamin C (p < 0.01) with the aerial parts showing stronger activity than the bulbs (p < 0.01). The extracts did not show any activity in the peroxidation test but displayed good H2O2 radical scavenging activity compared with quercetin (IC50= 52.0± 3.1 μg ml-1) which was used as positive control.Conclusion: The bulb and aerial parts of O. sintenisii aerial parts (at flowering stage) exhibited good but varying levels of antioxidant activities in nearly all the models studied.Keywords: Ornithogalum sintenisii ; Bulbs; Aerial parts; Antioxidant activity; Flavoniods; Phenol

Antidepressant and antioxidant activities of Artemisia absinthium L. at flowering stage

Artemisia absinthium (Asteraceae) is widely used in Iranian traditional medicine. Its effects may be correlated with the presence of antioxidant compounds. Methanolic extract of A. absinthium aerial part at flowering stage was screened for antioxidant activities by five complementary test systems. Also, its antidepressant activity was determined by forced swimming (FST) and tail suspension tests (TST). The extract showed good antioxidant activity. Also, the extract showed good reducing power activitybetween 50 and 800 ìgml-1. The extract exhibited a good activity in H2O2 scavenging (IC50 = 243 ± 12.15 ìg ml-1). IC50 for iron ion chelating activity was 419 ± 20.95 ìg ml-1. Quercetin, BHA, EDTA and ascorbicacid used as positive controls in parallel experiments. The extract showed high phenolic and flavonoid contents. Extract showed good antidepressant activity in FST. The extract shortened remarkably the immobility period during the FST and TST and exhibited a dose dependent activity. All test groups were significantly different form control group (P 0.05) in TST. LD50 was 3700 mg/kg. These results introduced A. absinthium aerial parts as an easily accessible and edible source of natural antioxidants and antidepressant

In vitro antioxidant and free radical scavenging activity of Leonurus cardiaca subsp. Persicus, Grammosciadium platycarpum and Onosma demawendicum

Antioxidant activity of the aerial parts of Leonurus cardiaca subsp. Persicus, Grammosciadium platycarpum and Onosma demawendicum were investigated employing six in vitro assay systems. IC50 for 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical-scavenging activity was in the order: O.demawendicum (221 ± 11.7) &gt; L. cardiaca (144 ± 12.1) &gt; G. platycarpum (45 ± 2.1) μgml-1, respectively. The extracts showed very good nitric oxide-scavenging and Fe2+ chelating ability activity. The L. cardiaca subsp. Persicus showed Fe2+ chelating ability activity as ethylenediaminetetraacetic acid (EDTA) (IC50 were 20 versus 18 μgml-1). None of the extracts exhibited good antioxidant activity in linoleic acid model. The extracts showed good reducing power that was better than vitamin C (p &lt; 0.05). G. platycarpum and L. cardiaca subsp. Persicus had higher total phenolic and flavonoid contents than O. demawendicum. The total phenolic compounds in the extracts were determined as gallic acidequivalents, and total flavonoid contents were calculated as quercetin equivalents from a calibration curve.Keywords: Antioxidant activity, Fe2+ chelating, 1,1-diphenyl-2-picryl hydrazyl (DPPH), phenol, Leonurus cardiaca, Grammosciadium platycarpum, Onosma demawendicu

Antioxidant and Antihaemolytic Activities of the Leaves of Kefe cumin (Laser trilobum L) Umbelliferae

Purpose: To investigate the antioxidant and antihaemolytic properties of the leaves of Laser trilubum grown in Gaduk, Iran. Methods: The antioxidant and antihaemolytic activities of the hydroalcohol extract of L. trilobum L. leaf were investigated by haemoglobin-induced linoleic acid peroxidation, scavenging of 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical, nitric oxide and hydrogen peroxide, as well as by assessment of reducing power and Fe2+ chelating activity, using standard methods. Phenol and flavonoid contents were determined as gallic acid and quercetin equivalents, respectively. Results: The extract showed antioxidant activity in some models, with 50 % inhibitory concentration (IC50) for DPPH radical-scavenging activity being 147.1 ± 7.5 μg ml-1. The extract showed good nitric oxide-scavenging activity of between 0.1 and 1.6 mg ml-1 (IC50 = 517.7 ± 23.1 vs. 20 ± 0.01 μg ml-1 for quercetin), weak Fe2+ chelating ability (IC50, 906.9 ± 37.8 μg ml-1), and low antioxidant activity in haemoglobin-induced linoleic acid system. However, it was capable of scavenging hydrogen peroxide in a concentration-dependent manner while also exhibiting potent antihaemolytic activity against H2O2 - induced haemolysis (IC50, 169.6 ± 6.9 μg ml-1). Total phenolic content was 75 ± 3 mg gallic acid equivalent/g and total flavonoid content 59.2 ± 2.1 mg quercetin equivalent/g. The amounts of gallic acid, quercetin and rutin were 0.99 ± 0.04, 0.63 ± 0.01 and < 0.10 μg/mg, respectively. Conclusion: L. trilobum exhibited good but varying levels of antioxidant and antihaemolytic activities in nearly all the models studied, when compared with controls.Keywords: Antioxidant activity, Laser trilobum, Antihaemolytic, Flavonoids, Kefe cumi

Biological and pharmacological effects of Delphinium elbursense

Antidepressant, antihypoxic and antioxidant activities of aerial parts of Delphinium elbursense were investigated employing nine various assay systems. Antidepessant activity was examined by using forced swimming test and tail suspension test in mice. The extracts at all tested doses show significant activity as compared to control group. Antihypoxic activity was investigated in two models, haemic and circulatory. The effects were pronounced and dose-dependent in both model of hypoxia. Extracts showed weak antioxidant activity in some models. IC50 for 1,1-diphenyl-2-picryl hydrazyl (DPPH) radical-scavenging activity was 116.2 ± 5.6 mg ml-1. Extracts showed nitric oxide-scavenging activity between 0.1 and 1.6 mg ml-1 (IC50 = 502.3 ± 18 mg ml-1) and a very weak Fe2+ chelating ability (IC50 = 1.01 ± 0.03 mg ml-1). It also exhibited low antioxidant activity in hemoglobin-induced peroxidation of linoleic acid but was capable of scavenging hydrogen peroxide in a concentration dependent manner. Extract show antihemolytic activity againts hydrogen peroxide (H2O2) induced hemolysis (558.7 ± 31 mg ml-1). The total phenolic compounds in extract were determined as gallic acid equivalents (52.24 ± 1.7) and total flavonoid contents were calculated as quercetin equivalents (17.26 ± 0.6) from a calibration curve.Keywords: Antidepressant, antihypoxic, Delphinium elbursense, flavonoid contents, forced swimming test, medicinal plants, phenolic contents, tail suspension testAfrican Journal of Biotechnology Vol. 9(34), pp. 5542-5549, 23 August, 201

In vitro antioxidant analysis of Achillea tenuifolia

Achillea tenuifolia (AT) is one of the most herbs are being used by people as a traditional medicinal remedy. Antioxidant activity of AT different extracts and total flavonoid and phenol levels in the extracts were investigated in this study. Plant extracts were prepared by maceration method using ethyl acetate, methanol and methanol-water (1:1). Folin Ciocalteu reagent in terms of gallic acid equivalent achieved the total phenol's content. AlCl3 was used as a reagent for flavonoid determination. Flavonoid content of the plant extracts obtained in terms of quercetin equivalent. DPPH radical scavenging effect of the extracts was determined by UV spectroscopy. Also in order to determine lipid peroxidation inhibition of the extracts of A. tenuifolia, ferric thiocyanate method with BHT, a synthetic reference standard, was carried out in this study. Phenol contents were 43.97 &#177; 0.034, 74.16 &#177; 0.55 and 106 &#177; 0.693 mg g-1 in theethyl acetate, methanol and methanol-water extracts, respectively. Flavonoid amount obtained in the ethyl acetate, methanol and methanol-water extracts were 10.6 &#177; 1.85, 23.1 &#177; 0.5 and 190 &#177; 1.3 mg g-1, respectively. The percentage of DPPH radical scavenged by the most active extract (methanol-water) of A. tenuifolia was 92% at a concentration of 1 mgml-1 greater than 94% of BHT at 2 mgml-1. IC50 of methanol-water extract and BHT were 0.015 and 0.053 mgml-1, respectively. Lipid peroxidation inhibition was observed by the most polar extract of AT about 91.84%. Phenol and flavonoids content confirm theexistence of more polar hydroxyl containing chemical structures in the plant. The potency of radical scavenging effect of methanol-water extract was about 3.5 times greater than synthetic antioxidant BHT. The inhibitory activity of the extracts on the lipid peroxidation of linoleic acid in ferric thiocyanate test was also significant (&gt; 90%). In this study we concluded that there is a direct relation between phenol and flavonoid content of plant extracts and the antioxidant activity. So that the greater amountof phenolic compounds leads to more potent radical scavenging and lipid peroxidation inhibition activities as it was observed in A. tenuifolia polar extract in the present study

A performance analysis of tidal turbine conversion system based on control strategies

Energy efficient generation from renewable energy sources is of major concern nowadays. A horizontal axis marine current turbine (HAMCT) of diameter 1.9 m is modelled using the blade element momentum (BEM) scheme and the turbine output parameters are given as an input to the electrical system for a tip speed ratio (TSR) of 5 and a power coefficient of 0.4. The design aspects of a buck-boost converter with proportional integral (PI) and sliding mode controller (SMC) is investigated for HAMCT system, with the highest power output of about 15.6 kW for a water velocity of 3 m/s. A comparison between PI controller and SMC are analyzed for the tidal turbine conversion system to obtain the desired output voltage with high efficiency is discussed here. The dynamic variation on load side to be controlled with dual loop controller to regulate the output voltage and to optimize the input current. In this paper performance and resemblance of control techniques which include sliding mode controller and PI controller are analysed with step and bode plot response. The system is designed for an output voltage range of 0.38 kV to 2.4 kV which is suitable for DC microgrids. The performance of HAMCT coupled with PMSG and the power converter with a controller is modelled and designed under MATLAB/SIMULINK environment