Asghar Ramezanian

Bio: Asghar Ramezanian is an academic researcher from Shiraz University. The author has contributed to research in topics: Ascorbic acid & Cold storage. The author has an hindex of 16, co-authored 55 publications receiving 836 citations. Previous affiliations of Asghar Ramezanian include United States Department of Agriculture.

Zinc alleviates salt stress and increases antioxidant enzyme activity in the leaves of pistachio (Pistacia vera L. 'Badami') seedlings.

Abstract: The mechanism(s) by which Zn alleviates NaCl stress was investigated in Pistacia vera L. 'Badami'. Pistachio seedlings were treated with 0, 800, 1600, 2400, and 3200 mg of NaCl kg -1 of soil, along with Zn (0, 5, 10, and 20 mg kg -1

Role of zinc in plant nutrition- a review

Abstract: Zinc is plant micronutrient which is involved in many physiological functions its inadequate supply will reduce crop yields. Zinc deficiency is the most wide spread micronutrient deficiency problem, almost all crops and calcareous, sandy soils, peat soils, and soils with high phosphorus and silicon are expected to be deficient. Zinc deficiencies can affect plant by stunting its growth, decreasing number of tillers, chlorosis and smaller leaves, increasing crop maturity period, spikelet sterility and inferior quality of harvested products. Beside its role in crop production Zn plays a part in the basic roles of cellular functions in all living organisms and is involved in improving the human immune system, due to its insufficient intake, human body will suffer from hair and memory loss, skin problems and weakness in body muscles.

Postharvest Biology and Technology for Preserving Fruit Quality

Abstract: Introduction and Overview Fruit Ripening Introduction Fruit Growth Fruit Ripening and Related Parameters Changes in Fruit Quality Attributes During Handling, Processing, and Storage Introduction What is Quality? Weight Loss Appearance Texture Flavor, Taste, and Aroma Bioactive Compounds Decay Mechanical Damage versus Fruit Quality Cold Storage and Fruit Quality Introduction Effect of Low Temperature Storage on Fruit Metabolism Cooling Rates Precooling Techniques Chilling Injury Heat Treatments Introduction Means of Heat Application Heat Treatments and Fruit Quality Storability Limitations: Heat Damage Calcium Treatments Introduction Calcium Sources and Pre- and Postharvest Methods for Application Pre- and Postharvest Calcium Treatments and Calcium Fruit Content Effect of Preharvest Treatment on Fruit Size Calcium Treatments and Fruit Firmness Calcium Treatments and Color, Soluble Solids, and Total Acidity Calcium Treatment and Bioactive Compounds Calcium Treatment, Cell Membrane Stability, and CI Reduction Effects of Calcium Treatment on Postharvest Decay Calcium Treatment and Ethylene Production and Respiration Rate Undesirable Effects of Calcium Treatments Polyamine Treatments Introduction Polyamine Biosynthesis and Regulation in Plant Tissues Polyamine and Human Diet Polyamine and Fruit Development Preharvest Polyamine Application and Fruit Ripening Postharvest Polyamine Application and Fruit Quality Polyamines and Chilling Injury Polyamines and Mechanical Damage Future Trends 1-Methylcyclopropene Treatments Introduction 1-MCP as Blocking Ethylene Receptors Postharvest 1-MCP Application 1-MCP in Nonclimacteric Fruits Preharvest 1-MCP Application 1-MCP on Physiological and Pathological Disorders Storage in Modified Atmosphere Packaging Introduction Films used in MA Packaging Generation of the Steady-State or Equilibrium Atmosphere Optimal CO2 and O2 Concentration Importance of Temperature Stability MAP and Fruit Quality Maintenance MAP Benefits for Storage of Fresh-Cut Fruits and Vegetables Future Research Needs Active Packaging Introduction Active Packaging Technologies Ethylene Adsorbers Antimicrobial Fruit Packaging Edible Coatings Future Trends Emerging Technologies Introduction Atmospheres with High O2 Biological Control UV-Irradiation References

Total phenolic contents and antioxidant activities of pomegranate peel, seed, leaf and flower

Abstract: Pomegranate (Punica granatum L.) is a nutrient dense food rich in beneficial phytochemicals. The aim of this study is to investigate and to determine antioxidant contents from local and highly consumed pomegranate variety called ‘Gabsi’. Peels, seeds, leaves and flowers were used to quantify total polyphenols, flavonoids, anthocyanins and hydrolysable tannins. Antioxidants contents were as follows: peel > flower > leaf > seed.Total polyphenols contents from peels were 85.60 ± 4.87 mg gallic acid equivalents per g dry weight (mg GAE/g DW), flavonoids (51.52 ± 8.14 mg rutin equivalents per g DW (mg RE/g DW), anthocyanins (102.2 ± 16.4 mg cyanidin-3-glucoside equivalents per g DW (mg CGE/g DW) and hydrolysable tannins (139.63 ± 4.25 mg tannic acid equivalent per g of DW (mg TAE/g DW). High free radical scavenging activity is reported in peels and flowers. Effective concentration at 50% (EC50) was 3.88 ± 0.33 µg/ml (peels) and 4.55 ± 0.97 µg/ml (flowers). Antioxidant capacity value was respectively 7.50 ± 0.83 Trolox equivalent antioxidant capacity (TEAC) mg/g DW (peels) and 6.39 ± 0.83 TEAC mg/g DW (flowers). Less important values were obtained from leaves (4.16 ± 1.35 TEAC mg/g DW) and seeds (1.10 ± 0.23 TEAC mg/g DW). Peels and flowers extract exhibited higher activities than seeds and leaves. All of these findings implied that bioactive compounds from pomegranate peels, flowers, leaves and seeds might be potential resources for the development of antioxidant function dietary foods. Extraction process of whole fruits may provide a commercial pomegranate juice with high antioxidants and consequently high usefulness antioxidant activities. Key words: Pomegranate fruit and leaves extracts, polyphenols, flavonoids, anthocyanins, total tannins, antioxidant activity.

Antibacterial, antioxidant and tyrosinase-inhibition activities of pomegranate fruit peel methanolic extract

Abstract: This study evaluated, using in vitro assays, the antibacterial, antioxidant, and tyrosinase-inhibition activities of methanolic extracts from peels of seven commercially grown pomegranate cultivars. Antibacterial activity was tested on Gram-positive (Bacillus subtilis and Staphylococcus aureus) and Gram-negative bacteria (Escherichia coli and Klebsiella pneumonia) using a microdilution method. Several potential antioxidant activities, including radical-scavenging ability (RSA), ferrous ion chelating (FIC) and ferric ion reducing antioxidant power (FRAP), were evaluated. Tyrosinase enzyme inhibition was investigated against monophenolase (tyrosine) and diphenolase (DOPA), with arbutin and kojic acid as positive controls. Furthermore, phenolic contents including total flavonoid content (TFC), gallotannin content (GTC) and total anthocyanin content (TAC) were determined using colourimetric methods. HPLC-ESI/MSn analysis of phenolic composition of methanolic extracts was also performed. Methanolic peel extracts showed strong broad-spectrum activity against Gram-positive and Gram-negative bacteria, with the minimum inhibitory concentrations (MIC) ranging from 0.2 to 0.78 mg/ml. At the highest concentration tested (1000 μg/ml), radical scavenging activities were significantly higher in Arakta (83.54%), Ganesh (83.56%), and Ruby (83.34%) cultivars (P 50%) against monophenolase and diphenolase activities at the highest screening concentration. The most active peel extract was the Bhagwa cultivar against monophenolase and the Arakta cultivar against diphenolase with IC50 values of 3.66 μg/ml and 15.88 μg/ml, respectively. High amounts of phenolic compounds were found in peel extracts with the highest and lowest total phenolic contents of 295.5 (Ganesh) and 179.3 mg/g dry extract (Molla de Elche), respectively. Catechin, epicatechin, ellagic acid and gallic acid were found in all cultivars, of which ellagic acid was the most abundant comprising of more than 50% of total phenolic compounds detected in each cultivar. The present study showed that the tested pomegranate peels exhibited strong antibacterial, antioxidant and tyrosinase-inhibition activities. These results suggest that pomegranate fruit peel could be exploited as a potential source of natural antimicrobial and antioxidant agents as well as tyrosinase inhibitors.