جستجوی مقالات مرتبط با کلیدواژه "chlorophyll" در نشریات گروه "پزشکی"

Vibrio cholerae O1 or non O1/non O139 is found in water ecosystems where it colonizes phytoplankton and has different lifestyle. This study aimed to investigate the impact of some algae extracts on the survival/growth of both V. cholerae strains.

Algae extracts consisting of three fractions, F1 containing chlorophyll-a, F2 containing chlorophyll-b, and F3 containing carotenoids, and raw extract (RAE) were obtained from the algal bloom collected in the Kaliao stream (Maroua, Cameroon). The survival and growth of V. cholerae O1 and V. cholerae non O1/non O139, in microcosms consisting of sterile saline with these extracts and peptone (PEP) respectively added at concentrations of 0.01, 0.05 and 0.1 mg/L, and 50/50 mixtures F1+F2, F2+F3, and F2+PEP at a concentration 0.05 mg/L, were compared during a 24h experiment.

The microcosms F2 and RAE did not support the growth of O1 strain; V. cholerae non O1/non O139 count in all algae extract microcosms ranging from 3.97 log (CFU/mL) to 5.2 log (CFU/mL). In all PEP microcosms, the counts of both strains reached an uncountable value. Microcosms F1+F2 and F2+F3 supported the growth of V. cholerae O1 and V. cholerae non-O1/nonO139 strains.

The algae compounds showed strain-specific effect on the growth of V. cholerae.

The present research aimed to investigate the effects of altitude on some physiological characteristics of Artemisia aucheri Boiss. Plant samples were taken from 15 areas in the Lakh Kuhik mountains. After determining the maps of work units, samples were taken systematically in each unit. Data were analyzed using descriptive statistics in SPSS. The highest and the lowest chlorophyll content were recorded at an altitude below 1200 m and above 1256 m, respectively. Dry and fresh weights were measured with a precision balance. The results indicated a direct relationship between the increase in plant Ca2+, Mg2+, and K+ contents and altitude. However, there was no significant relationship between altitude and plant P3-. Extraction was performed using a rotary evaporator (rotovap). Physiological and antioxidant traits and chlorophyll content of the samples were determined using the standard method (i.e., by a spectrophotometer). Results indicated that altitude had significant effects on physiological traits as the highest antioxidant activity was observed in regions with mid-latitude regions (i.e., 1228 m). Overall, it can be concluded that antioxidant content was lower at higher altitudes, and the best quality could be obtained from higher altitude plants (i.e., 1256 m). Similarly, fresh and dry weights were higher at higher altitudes because cytokinin levels in plants increased with reductions in auxin levels. In the next step, chlorophyll a and chlorophyll b were assayed separately. The results revealed that the chlorophyll content declined at high altitudes due to the presence of shortwave radiation.

Dust is one of the phenomena affecting the environment’s quality. The change in the vital indices of plant species is one of its important effects. The present study was conducted to investigate the effect of dust on the rate of photosynthesis and air pollution tolerance index (APTI) of the leaves of Ziziphus spina-christi (L.) Willd. in the city of Ahvaz in 2020.

A number of 10 Z. spina-christi (L.) Willd. trees were selected in each municipal district of Ahvaz metropolis. From each tree, one leaf sample was selected in the 4 main geographical directions, i.e., 4 samples from each tree species; overall, 40 leaf samples were collected in the whole region and sent to the laboratory to investigate the level of dust particles deposited in the four seasons of the year. Photosynthesis was measured based on the amount of chlorophyll by a spectrophotometer, and the APTI was calculated using Agbaire et al.’s method.

The results of measuring the weight of dust deposited on the leaves of Z. spina-christi (L.) Willd. trees in the city of Ahvaz showed that the greatest amount of dust was deposited on the leaves in the geographical north direction. The highest rate of photosynthesis was in the fall (53.76), and the lowest was in the spring (35.97). The mean APTI score of Z. spina-christi (L.) Willd. species in Ahvaz was 4.77.

These results indicate that this species has a favorable APTI against environmental pollutants, including dust. In general, the results of the present study confirm the significant association of the dust deposited on the leaves of Z. spina-christi (L.) Willd. with the rate of photosynthesis and the APTI.

Ascorbic acid has been used to treat many diseases and has recently been considered seriously in the Covid 19 event. Recent studies concerned with ascorbic acid status indicated high prevalence of vitamin C deficiency in many countries which plays an essential role in nutrition and lack of it in the diet causes disease. It is also an antioxidant in vegetables that prevent chronic diseases. Similar results have been observed for chlorophyll and its derivatives in treating acute diseases. There are several medicinal products derived from chlorophyll or its derivatives to treat diseases and variation of health benefits in chlorophyll. According to studies chlorophyll is a potential cancer-preventing agent and has been shown to have antioxidant and anti-mutagenic activities. The properties of chlorophyll are determined to reduce food wastage during processing and storage. Considering the importance of ascorbic acid and chlorophyll in food and especially the important presence of these two substances in vegetables, chlorophyll (spectrophotometric method for chlorophyll) and ascorbic acid (Ascorbic acid reduces oxidation-reduction indicator dye, 2,6-dichloroindophenol, to colorless solution) were measured in two popular vegetables: parsley and dill in three consecutive months of spring 2020 and the data were statistically analyzed using the SPSS 24. The results indicated that the last three months of plant growing just before harvesting, the ascorbic acid contents of both vegetables increased considerably. The results of chlorophyll contents in both substrates indicated increasing in all the stages. The average ascorbic acid reached its highest level in the third month of the spring (1.3000±0.120 mg.kg-1 for parsley and 0.2233±0.120 mg.kg-1 for dill); the difference in the amount of chlorophyll in the first and second harvest was nearly two times. The highest amount of chlorophyll in both vegetables belonged to the samples harvested in the third month of spring (0.343±0.006 mg.kg-1 for parsley and 0.580±0.006 mg.kg-1  for dill).The results of this study can help researchers to stablish a healthy and nutritious diet.

The main components of pistachios undergo significant changes during the ripening and development stages, making various uses of pistachios possible as fully grown product or green kernels Temporal Variations in Pistachio Nutrients. This research evaluated the main compounds and chlorophyll pigments of Ahmad Aghaei and Ohadi pistachios' varieties during ripening.

Pistachios were harvested from the gardens of Rafsanjan city at four different times (August 10th and 25th and September 10th and 25th). After removing the soft skin, the pistachio and its kernel were weighed, and the moisture content was measured using incubating. Subsequently, they were dried at 70 degrees Celsius in the oven for 48 hours then the amount of protein, oil, carbohydrates, Fiber, chlorophyll, and ash were measured. The obtained data were statistically analyzed using Minitab version 17 software, and the averages were compared using Duncan's test at the 5% probability level.

 The amount of moisture in both cultivars decreased during ripening, and it was in the range of 46.5-28.8 and 49.5-31.8 percent in Ohadi and Ahmad Aghaei cultivars, respectively. Fat, protein, carbohydrates, and fiber increased during the ripening period. The amount of ash did not show a significant change, but the amount of chlorophyll decreased during the ripening period.

The composition of the pistachio kernel changes during ripening, and by considering these changes and according to the purpose of using pistachios, the appropriate harvesting time and pistachio quality can be determined.

Argan oil extracted from the fruit of Argania Spinosa L. has many nutritional and therapeutic properties. This study was conducted to investigate the effect of Argan kernel roasting on physicochemical properties of cold-pressed oil. In this study, Argan kernels were roasted at 110 ° C for 30 minutes, and Argan oil was extracted from unroasted and roasted kernels by cold pressing. The results showed that in the oils extracted from unroasted and roasted Argan kernels, the predominant fatty acid was oleic acid and then linoleic and palmitic acids, respectively. γ-Tocopherol made up more than 80% of the tocopherol compounds in the samples, and spinasterol (78.44% in unroasted and 47.35% in roasted samples) were the predominant sterol compound of Argan oil. The sterol compounds of schottenol (38.69%), chlorophyll (0.43 ppm) and carotenoid contents (15.2 mg/kg) in oil extracted from roasted Argan kernels were higher, and there was no statistically significant difference (p < 0.05). According to the results, the oil extracted from roasted Argan kernels could be considered as a product with more desirable organoleptic properties and higher oxidative stability than the oil extracted from unroasted kernels during storage.

Datura species produce a wide range of tropane alkaloids with medicinal values. D. innoxia is a species of the Datura genus which is poisonous and has an unpleasant odor due to the presence of tropane alkaloids.

The study aimed to induction of polyploidy by colchicine treatment on downy thorn-apple and the effect of it on appearance and hyoscyamine content.

In order to induce tetraploidy in downy thorn-apple, a factorial experiment was carried out with two factors: colchicine concentrations (0.05, 0.1, and 0.2 %) and exposure time (48 and 72 h) with 3 plants for each treatment with using a cotton ball included colchicine on shoot tip. Morphological changes were observed and the plants were analyzed by flow cytometry in near to the flowering time.

The results showed that the concentration and exposure time of colchicine, and their interaction affected the percentage of tetraploidy. The maximum percent of tetraploidy was observed in concentration of 0.2 % and 72 h. On the other hand, the application of different concentrations of colchicine and exposure time didn’t have a significant effect on plant survival. The number of stomatal guard cells were decreased but no significant differences were observed in the content of total chlorophyll and carotenoids. Also, the hyoscyamine content in tetraploid plants was decreased to half in comparison to diploid ones.

In general, induction of tetraploidy in this plant could change some phenotypic traits but has a negative effect on hyoscyamine content.

Recently, Spirulina platensis has scientifically become popular because of its importance as food, feed, and a natural producer of pigments with specific nutritional and functional characteristics. In this study, the effect of various environmental factors affecting growth conditions of Spirulina platensis, including primary inoculation, light-dark cycle, cultivation time, Light-Emitting Diode (LED) composition, nitrogen source, carbon source, and NaCl concentration, on biomass, C-phycocyanin (C-PC), Allophycocyanin (APC) and chlorophyll-a contents were assessed using Placket-Burman Design (PBD). Results showed that out of the seven screened factors, four factors of carbon source, LED composition, light-dark cycle and NaCl concentration significantly affected biomass production (p<0.01). Among the investigated factors, nitrogen source, light-dark cycle, and NaCl concentration had significant effects on phycocyanin production (p<0.05). Results showed that cultivation time, light-dark cycle, and NaCl concentration significantly affected the production of allophycocyanin (p<0.05). Furthermore, NaCl concentration, carbon source, LED composition, cultivation time, and initial inoculation included significant effects on chlorophyll-a production (p<0.05). The present study screened variables affecting biomass, phycocyanin, allophycocyanin, and chlorophyll-a production as the first step in optimizing Spirulina platensis growth condition. Briefly, NaCl concentration was one of the factors which had a significant impact on all responses. The dark cycle also had an effect on three dependent variables except for chlorophyll-a production.

The plant species Cyamopsis tetragonoloba L. (Fabaceae) is a source of guar gum that has a variety of applications in the pharmaceutical industry because of its therapeutic properties. Other parts of the plant are also used as food and fodder. This study was conducted to evaluate some physiological changes and gum production of guar in response to foliar spraying with synthesized zinc oxide nanoparticles (ZnO-NPs).

ZnO-NPs were synthesized using guar gum by the co-precipitation method. The properties of the ZnO-NPs were investigated using various analytical techniques, including ultraviolet-visible spectroscopy (UV-Vis), scanning electron microscopy (SEM), transmission electron microscope (TEM), energy dispersive X-ray (EDX), Fourier transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD). The nanoparticles were sprayed on the leaves of the Saravan landrace of guar to study their effects on the physiological properties of the plant. The experiments were performed in a completely randomized design with three replications.

Treatment of plants with ZnO-NPs resulted in an improvement of some physiological properties. After exposure to 500 mg/L of ZnO-NPs, the contents of chlorophyll a, chlorophyll b, total chlorophyll, carotenoids, gum, and soluble protein were increased by 47.88%, 78.43%, 54.37T, 29.41%, 55.08%, and 52.12%, respectively. Additionally, the amount of Zn and insoluble sugars showed the highest increase, by 3.96 and 4.31 times, respectively. In contrast, soluble sugars content as well as the activity of catalase (CAT), peroxidase (POX), and ascorbate peroxidase (APX) reduced 0.69-, 2.23-, 1.60-, and 3.91-fold, respectively.

ZnO-NPs improved the physiological properties of guar at different concentrations, with the best effects obtained at the maximum concentration of 500 mg/L. The results of this study suggest that the ZnO-NPs synthesized by the biocompatible process are appropriate candidates to prepare guar gum to be used in pharmaceutical and therapeutic-based approaches.

Lead is a toxic heavy-metal pollutant which is hazardous to human health and the environment. Sodium nitroprusside is commonly used as a nitric oxide donor in plants. Nitric oxide is a bioactive molecule playing an important role in response to stress in plants. Weight, chlorophyll content, and the activity of catalase (EC 1.11.1. 6) and peroxidase (EC 1.11.1. 7) antioxidant enzymes of canola (Brassica napus L.) Hyola 401 in lead stress were investigated. This study tested the hypothesis that sodium nitroprusside plays an ameliorating role under lead-toxicity in canola. For seven days, thirteen-day plants were exposed to two levels of sodium nitroprusside (0 and 100 µM) and three levels of lead (0, 100, and 200 µM). Dry and fresh weight and chlorophyll content were decreased in lead stress, while sodium nitroprusside treatment increased weight and chlorophyll b in the same conditions. Lead stress increased the activity of antioxidant enzymes, and sodium nitroprusside treatment reduced their activity. The results showed that the use of sodium nitroprusside reduces lead toxicity.

As a rapidly-evolving global technology, nanotechnology has presumably brought drastic changes to our lives in the past two decades using engineered nanoparticles, whose penetration into industrial and non-industrial wastewater requires examination of their probable effects in aquatic ecosystems. The main objective of this work is to study the toxicological and biological effects of nanomaterials. Experiments on exposure of Dunaliella salina to SiO2 nanoparticles were performed for 72 hours with 7 treatments, two controls and three replicates were in each treatment and daily counting of cells was done in each tube. After extraction, chlorophyll a and carotenoid were measured using spectrophotometry method. Imaging of nanoparticles encountering algae cells was performed using cell imaging method by scanning electron microscope (SEM). The population growth rate alterations were evaluated. Probit analysis and softwares such as Excel and SPSS21 were used for data analysis. After exposure to SiO2 NPs, a significant difference was observed between chlorophyll a and carotenoid compared with control (p<0.05) and also carotenoid content was decreased with increasing the concentration in treatments and a significant difference was observed (P <0.05). Also, SiO2 NPs caused to inhibit growth in Dunaliella species.

The presence of large heavy metal concentrations in soil polluted with chemical weapons causes serious operational restrictions against cultivation of agricultural crops like wheat. To solve this problem, the usage of zeolite has been proposed as one of the most efficient practical approaches. The main objective of this research is the investigation of the influence of natural Iranian zeolite on sorption of cadmium (Cd2) and nickel (Ni2) and the investigation of growth characteristics of wheat in soil polluted with chemical weapons. The experiments were carried out in factorial arrangement in a randomized complete design with three replications during 2015-2016 crop season. Treatments with four levels of zeolite included: a1) 0%; a2) 0.5%; a3) 1.5%; and a4) 2.5% of soil weight and two soil samples, one obtained from out of the war zone (without contamination) (b1) and other was from contaminated soil to weapons (b2). Results showed that the polluted soil led to a significant enhancement in amount of Cd2 and Ni2 in shoots and roots of wheat. In addition, the findings revealed that the application of zeolite caused a significant reduction in Cd2 and Ni2 concentrations in shoots and roots and significantly increased dry matter, chlorophyll index and magnesium (Mg2) concentration in wheat. In general, results showed that zeolite released nutrients and stabilized heavy metals in polluted soil and the negative effect of soil polluted by toxic heavy metals was reduced in the plant, which lead to decontamination of soil and increase in safety of environment.

Developing algal industries in saline-alkali areas is necessary. However, suitable strains and optimal production conditions must be studied before widespread commercial use.. The effects of light, temperature, KNO3, and CO(NH2)2 on beta-carotene and biomass accumulation were compared and evaluated in order to provide scientific guidance for commercial algal production in northeastern Thailand.. An orthogonal design was used for evaluating optimal conditions for the algal production of three candidate Dunaliella salina strains (KU XI, KU 10 and KU 31) which were isolated from saline soils and cultured in the column photobioreactor.. The optimal light and temperature for algae growth were 135.3 μmol m-2 s-1 and 22°C, while the conditions of 245.6 μmol m-2 s-1 and 22°C induced the highest level of beta-carotene production (117.99 mg L-1). The optimal concentrations of KNO3, CO(NH2)2, and NaHCO3 for algae growth were 0.5 g L-1, 0.36 g L-1, and 1.5 g L-1, respectively, while 0, 0.12 g L-1 and 1.5 g L-1 were best suited for beta-carotene accumulation. The highest beta-carotene rate per cell appeared with the highest light intensity (12.21 pg) and lowest temperature (12.47 pg), and the lowest total beta-carotene content appeared at the lowest temperature (15°C). There was not a significant difference in biomass accumulation among the three Dunaliella strains; however, the beta-carotene accumulation of KU XI was higher than that of the other two strains.. Light and temperature were both relevant factors that contributed to the growth and beta-carotene accumulation of the three D. salina strains, and NaHCO3 had significantly positive effects on growth. The degree of impact of the different factors on cell growth was temperature > NaHCO3 > light intensity > KNO3 > CO (NH2)2 > strains; the impact on beta-carotene accumulation was temperature > light intensity > KNO3 > CO (NH2)2 > strains > NaHCO3.

Eutrophication is one of the detrimental environmental problems in water reservoirs dye to the irregular introducing nutrients (phosphorus and nitrogen). This study aimed to explore the eutrophication state of Ekbatan Reservoir, Hamadan, western Iran. Monthly sampling was conducted during April 2010 to March 2011. Seven sampling stations were selected in the various locations of the reservoir and the samples were collected in the depth of 50 cm. The grab sampling of water for nitrogen, phosphorous and chlorophyll-a was carried out at all localities by Hatch sampler. The trophic state of the dam was determined by Carlson''s Trophic State Index (TSI) and Chapra''s classification. The highest concentrations of phosphorus and chlorophyll-a were measured in August and the lowest concentration for both of the parameters was determined in February. The TSI index according phosphorus concentration showed that the reservoir was in eutrophic status during May to November and was in mesotrophic status over November to May. It seems that the eutrophication process in the lake was resulted from the rural wastewaters and agricultural fertilizers. Therefore, using long term management methods including prevent of uncontrolled discharge of agricultural wastewaters is recommended in order to reduce the eutrophication in the reservoir. Decrease of phosphorus concentration in the dam by 50% can convert the eutrophic state to mesotrophic state.