Nova Biologica Reperta

The effect of some chemical and natural compounds on polyphenol oxidase activity from apple fruits

Nader Chaparzadeh

Texture quality is an important factor in evaluating of fruits. The cut surfaces of the apple fruit turn brown because of the oxidation of phenolic compounds, triggered by polyphenol oxidase enzyme. Preventing the oxidation of phenolic substances and changing color of fruit are very important in the food industry. Due to the adverse effects of chemical additives on human health and increasing consumer preference for natural alternative compounds makes an interesting market for natural plant ingredients. This study was conducted to investigate the effect of some chemical and natural compounds including sodium metabisulfite, and citric acid, aromatic waters (sweats) of chicory, licorice and lemongrass on polyphenol oxidase enzyme activity of apple fruits. The activity of polyphenol oxidase was evaluated spectrophotometrically using pyrogallol as substrate. The optimum temperature and pH values were 32 °C and 7, respectively. It was found that the enzyme activity decreased due to use of natural compounds, sodium metabisulfite and citric acid. In conclusion, polyphenol oxidase activity can be reduced to prevent of fruits browning by using suitable natural compounds instead of chemicals.

Investigating the effect of salinity stress on photosynthesis and physiological traits of different lentil cultivars and its relationship with molecular markers

omid sofalian

Legumes are common crops in arid and semi-arid regions. This study was conducted to investigate three levels of salinity stress on 18 lentil cultivars in the greenhouse and laboratories of Mohaghegh Ardabili University in 2016-2016 in a factorial manner in the form of a randomized complete block design with three replications. The results of comparing average lentil genotypes were done with Duncan's method at the five percent probability level. Correlation was done in separate stress levels. The dendrogram of cluster analysis divided the genotypes into three groups in control and 60 mM conditions and two in 120 mM conditions. Genotypes 7 and 5 were in the top group in all groupings. The relationship between ISSR molecular markers and physiological traits was calculated among genotypes. All traits in three levels of salinity stress had a significant correlation with some ISSR markers. A total of 22 positive markers for physiological traits were identified at the control level, 9 positive markers at the moderate stress level, and 23 positive markers at the severe stress level. Among the 21 studied ISSR primers, the P8A11 marker had the largest number of gene loci related to the studied physiological traits.

Nanoemulsification of Syzygium aromaticum essential oil; Preparation, optimization, and study of its antibacterial activity against some gastrointestinal poisoning bacteria

Ali Mohammadi

The aim of the present work was to produce a stable nanoemulsion containing clove (Syzygium aromaticum) essential oil (PCLO) and evaluate its antimicrobial activity. The effect of the preparation technique, the type of surfactant and the ratio of surfactant to oil was evaluated to optimize the preparation formula of oil-in-water nanoemulsion. The optimized formula prepared by low energy production method containing 4% w/w PCLO and 12% w/w mixed surfactant (SDS + Tween 80) produced a clear and stable nanoemulsion for 90 days with an average particle diameter below 150 nm. The antibacterial activity of pure PCLO and its nanoemulsions (NCLO) was investigated by disk diffusion, agar well, and broth methods in 3 indicator bacteria of gastrointestinal infections, Escherichia coli, Staphylococcus aureus, and Salmonella typhimurium. Minimum inhibitory concentration (MIC) and bacteriocidal concentration (MBC) as well as dynamic killing time were determined in the tested bacteria. Strong antibacterial activity of PCLO and NCLO was revealed in the concentration range of 1000-2000 ppm. The killing kinetics study showed that during the first 15 minutes of exposure to NCLO at the MIC concentration, there was a rapid and extensive reduction in the amount of viable microorganisms. The presented data, considering the optimal performance of antimicrobial substances in food, cosmetics and chemical industries, can help in the rational design of nanoemulsion-based essential oil delivery systems.

The effect of inoculation with mycorrhizal fungus Glomus caledonium and zinc chelate spraying on the quantity and quality of Satureja bachtiarica Bunge essential oil at full flowering stage

Fatemeh Nejadhabibvash

The aim of this study was to evaluate the changes in the essential oil chemical composition of Satureja bachtiarica Bunge were inoculated by spores of the arbuscular mycorrhizal inoculation Glomus caledonium and foliar application of zinc chelate levels (0, 2, 4 and 8 g/L) in 2019, at Zarrin Giah greenhouse of Urmia city in West Azerbaijan Province, in a randomized complete block design with three replications. Plants were harvested at full flowering stage. Essential oils were obtained by Clevenger apparatus and were analyzed by GC and GC/MS. Comparison of means by Duncan's multiple range test showed that inoculation with Glomus caldonium had no significant effect on the essential oil yield of Satureja bachtiarica flowering shoots, but the foliar application of zinc chelate had statistically significant effect. However, there was no difference among different concentrations of zinc chelate in terms of effect on essential oil yield. The treatments also changed the essential oil composition compared to the essential oil of the control group. These changes included the reduction of beta-caryophyllene, sabinen hydrate, borneol and carvacryl acetate compounds and the increase of citral and octyl phthalate in the plant inoculated with mycorrhiza, as well as the increase of carvacrol in the essential oil of plants treated with zinc chelate. Also, inoculation with mycorrhizal fungi and zinc chelate foliar application increased the amount of sesquiterpene & diterpene and monoterpene compounds, respectively.

Comparative investigation of biological properties of extract and silver oxide nanoparticles synthesized from aqueous extract of calyx of eggplant

Jamileh SalarAmoli

Calyx of eggplant is recognized as agricultural byproducts containing significant levels of phenolic, flavonoid, and anthocyanin compounds that facilitate the reduction of silver ions, enabling the eco-friendly production of silver oxide nanoparticles through a green synthesis approach. The utilization of silver oxide nanoparticles has garnered considerable interest in various industries due to their versatile applications and environmentally sustainable nature. Various analytical techniques such as ultraviolet- visible spectrophotometry, X-ray diffraction, Fourier transform infrared spectroscopy, scanning electron microscopy, and dynamic light scattering were employed to confirm the formation of silver oxide nanoparticles and characterize their properties. The antioxidant, antibacterial, and antifungal activities of the silver oxide nanoparticles and the aqueous extract of calyx of eggplant were evaluated through assays including 1,1-diphenyl-2-picrylhydrazyl radical scavenging, 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radical inhibition, disc diffusion, minimum inhibitory concentration and minimum bactericidal concentration. The absorption peak at 422 nm confirmed the presence of silver oxide nanoparticles, with a particle size of approximately 140 nm determined by DLS analysis and a spherical shape observed through SEM imaging. The biological activities of the silver oxide nanoparticles, including their antioxidant properties and antimicrobial effects were found to be superior to those of the aqueous calyx of eggplant extract.

Ecological niche overlap from occurrence of two cyprinid sympatric species, Paracapoeta trutta and Capoeta damascina in the Sirvan River, Persian Gulf Basin

Soheil Eagderi

This study was conducted to investigate the ecological niche overlap of two sympatric species, Paracapoeta trutta and Capoeta damascina in the Iranian part of the Sirvan River, Persian Gulf basin. For this purpose, during the winter of 2021, sampling was done from eight stations (each with three repetitions). After identification, samples were released into the same sampling sites. Then some 10 environmental factors including depth, water velocity, river width, pH, temperature, electrical conductivity (EC), total dissolved solids (TDS), Altitude, slope, and dissolved oxygen were measured and recorded. Investigating the habitat suitability indices of P. trutta were recorded as pH 7.5-8, temperature about 10°C, TDS 150mg/liter, EC 400μS/cm, altitude 1150 m, depth 15cm, river width about 9m, velocity 1 m/s, slope 2% and dissolved oxygen 9mg/l and for C. damascina as pH 6-6.5, temperature about 10°C, TDS 180 to 200mg/l, EC 300μS/cm, altitude 1150m, depth 25cm, river width about 6m, velocity 0.5 m/s, the slope is 2% and the dissolved oxygen 8mg. The results of the ecological niche overlap showed that two species based on studied environmental factors had the highest overlap value for dissolved oxygen (0.646) and the value for temperature (0.293). The average ecological niche overlap was 0.432 for the two species.