Physiological and biochemical responses of basil (Ocimum basilicum) seedlings to different concentrations of zinc

Zinc (Zn 2+ ) is one of the essential micronutrient elements for plant growth. In the present study, effect of different concentrations of zinc on some physiological and biochemical properties of basil (Ocimum basilicum) was investigated. Basil seedlings were exposed to six zinc (ZnSO 4 ) levels (0, 50, 100, 200, 400, and 800 mg/L) in 3 days’ intervals for a period of 30 days. The root and shoot growth, leaf number and area, photosynthetic pigments content, total soluble sugars and proteins, phenolic compounds, antioxidant power and mineral elements contents including zinc and potassium were significantly increased in effect of zinc levels up to 200 mg/L. Inversely, ferrous and calcium contents was drastically decreased concomitant with increasing zinc concentration but magnesium content remained unchanged. Our results indicated a dual role of zinc with optimum concentration of 200 mg/L, and a decrease in the root and shoot growth, pigment and phenolic contents under and over optimum concentration, whereas sugars and protein accumulation were occurred concomitantly with increasing zinc in the medium. However, the decrease of these parameters at the highest zinc concentration did not reach the level of control plants, which means that this species has a high resistance against zinc metal stress and because of the relative accumulation of zinc in polluted areas may has an important role for human nutrition. In general, the results point to important role of zinc in maintaining and protecting of basil seedlings against radical oxygen species

robial and Antioxidant Activities and Determining Phenolic and Flavonoid Contents of the Extracts of Five Species from Different Families of the Medicinal Plants Grown in Sistan and Baluchestan Province

Background & Objectives: Traditionally use of the medicinal plants for treating of diseases. This present study is carried out to evaluate the antimicrobial and antioxidant activities and determination of total phenolic and flavonoid contents of three extracts (Methanolic, Ethanolic and Aqueous) of five different species of medicinal plants such as Withania somnifera L. Dunal., Salvia rhytidea Bent, Levisticum officinale L, Seidlitzia rosmarinus L., and Achillea wilhelmsii L. Material & Methods: After preparing the extracts with maceration method, antioxidant activities were determined by two methods (DPPH and FRAP) and antimicrobial activities were estimated by Disk-Diffusion method against bacteria (Staphylococcus aureus, Bacillus cereus, Escherichia coli and fungi (Aspergillus niger and Candida albicans) and phenolic and flavonoid contents were determined by Folin-Ciocaltiu, Aluminum Chloride colorimetric. Results: The results showed that, the methanolic extract of W. somnifera had maximum total phenolic (41.45±4.64 mgGAE/gExtract) and flavonoid contents (35.21±2.54 mgQUE/gExtract) and antioxidant activity, (IC50=8.12±1.36µg/ml, 58.19±1.68 mM Fe2+/mgExtract) and antimicrobial activity against Staphylococcus aureus and Candida albicans with the diameter of inhibition zone (29±1.06 and (27±1.00 mm) respectively. In contrast, the aqueous extract of L. officinale had minimum value of total phenolic (17.12±1.93 mgGAE/gExtract) and flavonoid contents (12.61±2.06 mgQUE/gExtract) and antioxidant activity (IC50=121.43±3.36µg/ml, 13.74±2.52 mM Fe2+/mgExtract) and antimicrobial activity against Bacillus cereus and Aspergillus niger with the diameter of inhibition zone (4±0.57 and 5±1.00 mm) respectively. Conclusion: Overall, based on the results, the studied plants can be a good candidate for the treatment of diseases caused by oxidative stress, and diseases are caused by pathogenic microbes

Investigation of antioxidant and antimicrobial activities and phytochemical Compounds of essential oil and different extracts of Cymbopogon olivieri (Boiss.) Bor. from Sistan and Baluchestan province

Background: In this study antimicrobial activities, antioxidant activities and phytochemical compounds in the essential oil and extracts of Cumbopogon olivieri were studied.Material & Methods: For investigation of phytochemical compounds such as total phenolic and total flavonoid contents in three extracts (Methanolic, ethanolic and aqueous) and essential oil by Folin-Ciocaltiu, Aluminum Chloride colorimetric and GC-MS methods and antioxidant activities of extracts by two methods (DPPH and FRAP) and antimicrobial activities of essential oil and extracts of Cumbopogon olivieri against three bacteria such as Staphylococcus aureus, Bacillus cereus, Escherichia coli and two fungi such as Candida albicans and Aspergillus niger by two methods (well diffusion and Minimal Inhibitory Concentration (MIC)) respectively.Results: The results showed that, the methanolic extract had maximum total phenolic and flavonoid contents and antioxidant activity and aqueous extract had minimum value of this compounds and activity. In investigation of essential oil, three compounds such as piperitone (82.95), carene (2.493) and limonene were the major constituents. The results of antimicrobial activity showed that, the essential oil and extracts had good inhibition effect on all of bacteria and fungi and this inhibition depends to concentration.Conclusion: Overall, based on the results obtained, the plant can be a good candidate for the treatment of diseases caused by oxidative stress, and diseases caused by pathogenic microbes. Also due to power up the plant in the elimination of pathogens, could be a viable alternative to antibiotics

Optimization, Characterization, and Investigation of Antibacterial Activity of Gold Nanoparticles Biosynthesized by Aqueous Extract of Seidlitzia rosmarinus

Background and Objectives: The advantages of biological methods are Low cost, non-toxicity, production of high purity nanoparticles, low time-consuming, and completeness reation time. In the present study, biosynthesis of gold nanoparticles using aqueous extract of Seidlitzia rosmarinus and thier antimicrobial activity, were investigated. Methods: In this study, after preparing the extract, 2 ml of it was added to 4 ml of HAuCl4.3H2O with concentration of 1mM, and the color of solution immediately changed to purple. The parameters affecting the synthesis of nanoparticles [such as pH of reaction medium, extract volume, concentration of gold (III) salt, temperature, and reaction time], were assessed and optimized using UV-vis spectrophotometry. A transmission electron microscope (TEM) was used to characterize the nanoparticles. The antibacterial activity of nanoparticles against four species of pathogenic bacteria (Staphylococcus aureus, Enterococcus faecalis, Escherichia coli, and Salmonella typhimurium), were assessed by agar well diffusion method. Results: Gold nanoparticles showed the maximum absorbance at 544 nm. It was found that the nanoparticles have spherical shape and their average size was 10-18 nm. Also, the results of antibacterial activities showed that the synthesizied nanoparticles had relatively high antibacterial activity. Conclusion: In the current study, the aqueous extract of Seidlitzia rosmarinus due to its seccondary components and antioxidant activity, has high potential in reduction of gold metal ions as well as synthesis and stabilization of gold nanoparticles, and these synthesized gold nanoparticles were also relatively high antibactrial activity