nitrate

Considering the variety of nutritional supplements, choosing a suitable and available supplement for improving sports performance is important. Spinach is one such dietary supplement that contains inorganic nitrate/nitrite that appears to enhance vascular function, cognition, and physical performance. Therefore, this study aimed to investigate the effect of short-term consumption of spinach powder on the aerobic and anaerobic performance of active young individuals.

After specifying the criteria for entering the research, 14 healthy and active men and women (age: 22.71±1.81 years, body mass index: 22.70±2.57 kg/m2) participated in this research. Once the subjects provided written consent, they were randomly assigned to two groups: supplement (50 g per day of spinach powder) and placebo (50 g per day of rice flour+green food powder). Both groups followed this regimen for 14 days. Before and 48 hours after the last dose of the supplement,  the aerobic and anaerobic performance of the individuals' upper and lower bodies was evaluated using the Astrand ergometer test, Bruce treadmill test, 30-second Wingate cycling test, and 30-second hand crank test. To analyze the data, a 2×2 ANOVA test and Bonferroni pairwise comparisons were used in SPSS software version 26.

The results of this study indicated that 14 days of spinach powder consumption had no significant effect on maximum oxygen consumption in maximal tests (P=0.59) and sub-maximal tests (P=0.08), as well as on peak (P=0.12), average (P=0.46), and minimum (P=0.63) anaerobic power, maximum pedal speed (P=0.55) and maximum speed retention time in the upper body (P=0.12) and lower body (P=0.97).

The results of this research showed that short-term consumption of spinach failed to improve the aerobic and anaerobic performance of active individuals. Therefore, the results do not support the use of spinach for enhancing athletic performance indicators.

Nitrates have long been considered indicative of drinking water quality and a critical concern for human health. The evolution of advanced models for water quality management has spurred decision-makers to incorporate artificial intelligence technologies into water quality planning. This study aims to employ the AdaBoost model, one of the cutting-edge models in water quality management, to predict nitrate concentrations in groundwater using pH and EC (Electrical Conductivity) as input variables.

Initially, the study analyzed the Pearson correlation matrix and subsequently determined the input variables for multiple AdaBoost models with varying hyperparameters. A sensitivity and dependence analysis of the model's input variables was conducted to assess their impact on nitrate prediction.

The results obtained from the AdaBoost model reveal R-squared (R2) values of 0.915 for the training dataset and 0.924 for the test dataset. Additionally, the Mean Squared Error (MSE), Root Mean Squared Error (RMSE), Mean Absolute Error (MAE), and Mean Absolute Percentage Error (MAPE) scores for the training dataset were recorded as 1.02, 1.01, 0.823, and 7.3%, respectively. For the test dataset, these metrics were observed in the order of 0.228, 0.477, 0.375, and 3.2%. The model's sensitivity analysis identified the pH variable as the most influential factor in nitrate prediction.

The model analysis demonstrates that the proposed method performs well in predicting nitrate concentrations. This approach holds significant potential for implementation as an intelligent system for forecasting water quality parameters.

Today, environmental pollution, including water pollution, has become a global issue, and human life is dependent on the safe drinking water. This study aimed at spatial analysis of minerals and heavy metals in drinking water distribution network in Kurdistan Province’s villages.

In this descriptive-analytical study we assessed the concentrations of nitrate, nitrite, total soluble solids, fluoride, arsenic, lead, and cadmium in drinking water of all villages connected to water distribution network (1524 villages) in Kurdistan Province from 2015 to 2017. To describe the concentrations of the studied chemicals, spatial distribution maps were plotted using Arc GIS V. 10.3 software. Other statistical analyses including the analysis of the mean difference of the concentrations of nitrate, nitrite, and total soluble solids in the studied cities were performed by one-way analysis of variance using SPSS V. 22 software.

According to the results of this study, tap water in 1485 villages of Kurdistan Province (97.44%) contained nitrate and the amount of this ion in the drinking water of 31 villages (2.03%) was above the national and WHO standards. The mean concentration of total soluble solids in Bijar City was significantly higher than that in other cities (P <0.001). The mean concentration of fluoride in the drinking water of rural areas of Kurdistan province was 0.19 ± 0.25 mg/l, which was lower than the value determined by national standard of Iran (0.5-1.5 mg/l). The concentrations of arsenic in the tap water of 47 villages of Bijar (23 villages), Qorveh (11 villages), Saqez (7 villages), Dehgolan (5 villages), and Kamyaran (1 village), respectively, were higher than the maximum permitted value.

Continuation of the current trend, especially in agricultural sector and uncontrolled use of groundwater resources in agriculture, will lead to decreased water quality. Therefore, it is necessary to monitor agricultural activities and use of fertilizers.

Nitrate is an essential nutrient for the growth of plants. The presence of it in vegetables, water and other foods, is a serious threat for human health. Human body receives about 80% of nitrate from fruits and vegetables. The purpose was to determine the amount of nitrates in some vegetables and cucurbits (basil, mint, radish and tomato) that are sold in fruit and vegetable market of Zahedan city in 2020 year.

Hundred and twenty samples were selected and their nitrate content were measured by HPLCmethod. The significance level was less than 5%.

Mean of nitrate in, tomato, mint, radish and basil were 20.55, 515.76, 585.73 and 591.7mg/kg respectively. The mean of nitrate in basil was slightly higher than the radish but difference wasn’t statistically significant. There was statistically significantdifference among mean of nitrate in investigated vegetables (p value < 0.05). Mean of nitrate in basil was higher than others (p value < 0.05). A statistically significant difference was observed among mean of nitrate in vegetables namely tomato, mint, radish and basil in the investigated stalls (p value < 0.05).

Amount of nitrate in samples were lower than the national standard limit that is not harmful for human health. It can be concluded that the vegetables sold in Zahedan city are good interms of nitrate content and they don’t cause health problems. As high consumption rate of different type of vegetables by human and variation of their nitrate concentration, additional investigation and permanent control of their nitrate concentration isnecessary.

Excessive intake of nitrite and nitrate threatens human health. The aim of this study was to determine the levels of nitrite and nitrate in some summer vegetables cultivated in Bastam region of Shahroud.

the study was conducted in the summer. The study area was divided and a total of 25 summer vegetables, 15 soil samples, and three water samples were measured to determine the levels of nitrate and nitrite according to the Standard instruction (No. 4106).

The total average of nitrate in cucumber, tomato, potato, eggplant and onion was 850.1 ± 65.2, 642.1± 25.4, 48.6 ± 2.5, 14.8 ± 4.5, 791.3±52.1 mg/kg fresh weight, respectively and this level for nitrite was equal to 9.23 ± 0.1, 7.2 ± 0.8, 0.52 ± 0.04, 0.9± 0.05, 5.3±0.32 mg/kg fresh weight that all values were less than the standard level.The level of nitrate and nitrite in the soil was 1250.68 ±562.2 and 98.1 ± 15.2 mg/kg soil weight, respectively. The level of nitrate and nitrite in the water was 5.68±2.2 and 0.23±0.2 mg/l, respectively.

Due to the high consumption of vegetables and summer vegetables in summer and spring, which are also the fertilizing seasons for plantsand shrubs,it is recommended that managers and farmers pay more attention to the process of cultivation and fertilization of agricultural products, as well as frequent monitoring of the level of nitrite and nitrate in the country's vegetables.

As a nitric oxide (NO) donor, nitrate administration improves renal function in male animals. This study aims to determine the effects of chronic administration of different doses of nitrate on kidney function in normal adult female rats by measuring serum urea and creatinine and assessing the estimated glomerular filtration rate (eGFR).

Two-month old female Wistar rats were divided into six groups (n=10/group): the control group received tap water, and five nitrate-treated groups received water containing 50, 100, 150, 250, and 500 mg/L sodium nitrate in their drinking water for six months. At the end of the study, body weight, serum urea, and serum creatinine were measured, and eGFR was calculated.

Serum urea levels decreased by 16.9% (P=0.037) at dose 100 mg/L and increased by 15% (P=0.064) and 24.7% (P=0.003) at doses 250 and 500 mg/L, respectively, after nitrate administration. Serum creatinine levels decreased only at dose 100 mg/L by 16.3% (P=0.002) after nitrate administration. Moreover, eGFR increased at dose 100 mg/L (11.5%, P=0.046), decreased at doses 250 (13.8%, P=0.018) and 500 (16.9%, P=0.004) mg/L, and remained constant at doses 50 and 150 mg/L after nitrate administration.

Chronic nitrate administration exerted multiphasic effects on renal function in female rats; i.e., the low dose had no effect, the intermediate dose had a protective effect, and the high dose had detrimental effects on renal function.

 studies show that antioxidants prevent conversion of NO3/NO2 to nitrosamines compounds. tha aim of this study was to determine the potential effect of interaction between dietary intakes of vitamin C and NO3/NO2 on urinary and serum levels of NO3/NO2.

This cross-sectional study included 251 adults aged >19 years was performed in the phase 6 of  the Tehran Lipid and Glucose Study in 2015. Food intake was assessed using a semi-quantitative food frequency questionnaire. The average daily intake of nitrate and nitrite and vitamin C was estimated. Serum and urine levels of nitrate and nitrite were measured using  the Grease method. In order to determine the effect of vitamin C on the interaction of nitrate and nitrite in urine and serum, linear regression test was used to modify the effects of confounders.

There was a significant correlation between intake of nitrate and its urine level, above the median level of vitamin C intake (B = 0/004, P-value = 0/004). Also, this correlation remained significant after adjusting for age, sex, body mass index, calorie intake (B = 0.03, P-value = 0/001). The effect of vitamin C interactions on nitrate intake and urine level in the adjusted model for nitrate and nitrite was also found to be significant (B = 0/003 P-value = 0/001).

Increased intake of vitamin C significantly increases urinary excretion of nitrate and it is effective in  the interaction between dietary intakes and urinary excretion of nitrate.

Despite the higher prevalence of kidney dysfunction in females, the effects of nitrate have mainly been studied in males. This study aimed to determine the effects of long-term sodium nitrate administration on kidney function in normal adult female rats by assessing estimated Glomerular Filtration Rate (eGFR), serum urea, and serum creatinine.

Female Wistar rats were divided into two groups (n = 10 per group). The control group received tap water, and the nitrate group received tap water containing 100 mg/L sodium nitrate for nine months. Bodyweight, serum urea, and serum creatinine were measured at the beginning and end of the study, and eGFR was calculated. The nitric oxide metabolites (NOx) levels were also measured at the end of the study in serum and kidney tissue.

The body weight, serum urea, and creatinine levels of rats in the control group were significantly higher, and eGFR was significantly lower at the end of the study compared to the beginning of the study. Nitrate administration for nine months prevented increases in body weight, serum urea, and creatinine and decreases in eGFR. Nitrate-treated female rats also had higher NOx levels in serum and kidney tissue.

Nitrate administration improved kidney function in female normal adult rats. These beneficial effects may be associated with increased serum and kidney levels of NOx.

Municipal wastewater effluents contain high amounts of nitrate and phosphate nutrients. Microalgae have been considered as a bioreactor to absorb nutrients in wastewater due to their environmental friendliness and ability to produce valuable products. In the present study, the effects of light-dark cycles and microalgae biomass concentrations on the nitrate and phosphate removal from municipal wastewater were investigated.

In this study, Chlorella vulgaris (green microalgae) was first cultured in a membrane photobioreactor with a light intensity of 300 μmol photons in three light cycles (12 h light-12 h dark, 16 h light-8 h dark, and 24 h light and 0-h dark). Afterward, the best light cycle in municipal wastewater effluent was investigated at constant concentrations of microalgae (0.5 g L-1, 1 g L-1, and 1.5 g L-1).

According to the results, the highest growth rate (2.3 g L-1) and the highest amount of nitrate and phosphate removal (87% and 86%) were obtained in the 24-0 light cycle. Following that, the concentration of 1 g L-1 of microalgae in the 24-0 light cycle was recorded as the highest amount of nitrate and phosphate removal from municipal wastewater (91% and 87%, respectively).

The results indicated that light-dark cycles and initial concentrations of microalgal inoculation could have an undeniable effect on the growth of microalgae. Moreover, it could have a significant impact on the removal of nitrate and phosphate from municipal wastewater through microalgae cultivation. This removal percentage increased with the optimization of light conditions and biomass concentration.