h. kiani

Using renewable energy is an efficient method for addressing the drawbacks of utilizing fossil fuels. The study focuses on a multigeneration system that integrates PTC solar collector and geothermal energy, along with two ORC cycles, a single-effect absorption refrigeration cycle, a PEM electrolyzer, and a dryer. A TEG unit is utilized in the ORC cycles to increase power production. The system is analyzed from energy, exergy, and exergoeconomic perspectives using EES software. Parametric analysis is conducted to assess the impact of crucial parameters on the system's performance. The examination of overall results reveals that the energetic and exergetic efficiencies of the multigeneration system are 41.58 and 25.61%, respectively. The power generated by ORC1 turbine and ORC2 turbine are 461.9kW and 227.6kW, respectively. Introducing TEG units in place of condensers in the ORC cycles results in increased power production to 138.2kW and 328.2kW for ORC1 and ORC2 cycles. The energetic and exergetic COPs of the system are 0.8103 and 0.3484, respectively. Additionally, the multigeneration system is capable of producing 493.1 kg/day of hydrogen. Lastly, six different working fluids in the ORC cycle were investigated. It is demonstrated that among the 6 working fluids, n-pentane exhibited the best performance.

Microbial fermentation using solid substrates offers a safe, cost-effective straightforward approach for generating valuable organic acids, constituting the third-tier product category in addition to enzymes and secondary metabolites. This study investigated potentials of soybean meal paste as a substrate without the need of additional supplements, with the specific aim of propagating probiotic cultures and assessing performance of Bifidobacterium lactis in fatty acid production.

A homogenized soybean meal paste was prepared with an initial moisture content of 65% to begin solid-bed fermentation. This paste was inoculated with 4% of microbial culture and then incubated at 37 °C.

After 24 h of fermentation, strain showed significant acidification and increases in cell numbers. Moreover, the microorganism demonstrated significant capacity to modulate levels of saturated and unsaturated fatty acids within the media, in contrast to the control media. The fatty acid composition shifted to a higher proportion of saturated fatty acids as well as further decreases in omega-3 acid than omega-6 fatty acid. Inoculation of the bacteria at 4% with substrate fermentation led to significant increases in the microbial population to 9.98 log CFU/g and decreases in pH levels to 5.1 at the optimal temperature of 37 °C.

The soybean paste demonstrates potentials as a carrier for this probiotic microorganisms, facilitating fatty acid production. This microorganism enhanced nutritional and functional characteristics of the substrate, rendering soybean meal an appealing option for the production of innovative products for market consumers. The findings suggest promising solutions for the cost-effective and sustainable production of organic acids and fatty acids using solid substrates and probiotic microorganisms.

 It was shown that contamination of agricultural pasturage with fertilizers, application of sewage and effluents in irrigation, use of pesticides and air pollution have led to the entrance of chemical contaminants, including metals, into plants. On the other hand, food processing is (handling, processing, transportation) considered as an important way of food contamination. Vegetable oils are essential in human dietary which is introduced as crucial sources of energy, fat soluble vitamins, and essential fatty acids. Sesamum indicum L., known as sesame seed, has been cultivated in Asian countries from ancient times as vegetable oil for cooking and seasoning ingredients. In recent years, the sesame oil has been considered due to its high antioxidant activities and nutritional properties. Due to the use of sesame seeds extracted oil in two form of ardeh oil and sesame oil, the amounts of mineral elements (phosphorus, potassium, iron, nickel, cobalt, manganese, calcium and magnesium) in sesame seeds and its extracted oils (ardeh oil and refined sesame oil) were investigated.

 In order to determine the mineral concentration, refined sesame oil and ardeh oils were prepared from an imported sesame seed. In order to prepare the sesame oil, sesame seeds were put into a cold presser and the oil was extracted under low pressure. The Ardeh oil was prepared by adding water to sesame paste in the ratio of 2.2:10 and oil was separated by centrifugation. The sesame seeds and oil samples (refined sesame oil and ardeh oils) were digested by microwave digestion method in presence of 5 ml 65% nitric acid and 2 ml of hydrogen peroxide (H2O2). The digested samples were then filtered through 0.45 µm filter membrane. Then, the concentrations of phosphorus, potassium, iron, nickel, cobalt, manganese, calcium and magnesium in sesame seeds, ardeh oil and refined sesame oil were examined using Inductively Coupled Plasma - Optical Emission Spectroscopy (ICP – OES).

 In the present study, the limit of detection (LOD) for each studied mineral elements were determined as nickel: 4 mg/kg, magnesium: 0.00066 mg/kg, manganese: 0.000134 mg/kg, phosphorus: 0.384 mg/kg, cobalt: 0.594 μg / kg, iron: 0.000797 mg/kg, potassium: 0.00394 mg/kg, calcium 0.005 mg/kg. According to the results, the highest amounts of mineral elements were detected in sesame seeds. The achieved results showed that the method of sesame oil extraction can reduce the mineral elements in the final sesame oils. The amounts of mineral elements in sesame seeds were estimated as P > Ca > K > Mg > Fe > Mn > Co > Ni. The pattern of mineral elements in Ardeh oil was reported as P > Fe > K > Co > Mg > Ni > Mn > Ca. The reduction pattern was reported as P > K > Fe > Ni > Co > Mn > Ca > Mg in refined sesame oil. As can be seen the order of mineral elements was changed in two oil samples and sesame seed. It was shown that except for K and Ca, all mineral elements in ardeh oil were higher than refined sesame oil. As can be seen, the refining process was effectively reduced the metals in oil samples. On the other hand, high amount of mineral elements in sesame seed in comparison to extracted oils could be attributed to lack of processing methods which are present in oil production in both methods. 

 It should be considered that presence of different metals in vegetable oils could facilitate the oil deterioration and oxidization as well as oil shelf life reduction. Since the most of the sesame lots in Iran are imported, it is necessary to monitor the amount of mineral elements.

Nigella sativa L. is a valuable medicinal plant that is widely used in different industries. Accumulation of compatible osmolytes is one of the common responses of plants under drought stress. To investigate the effects of irrigation regimes and biochar (resulting from the heating of cattle manure) on N. sativa, a factorial experiment was conducted in a completely randomized design with three replications in the greenhouse of the Faculty of Agriculture at the University of Kurdistan in 2018. The experimental factors consisted of three drought stress levels (40, 70, and 100% of FC) and two biochar use levels (0 and 15 tons.ha-1). The ANOVA results showed that the interaction effects of drought stress and biochar were significant on hydrogen peroxide, malondialdehyde, superoxide dismutase, peroxidase, proline, soluble carbohydrates (water and ethanol soluble), and osmotic potential. Increasing the intensity of drought stress enhanced the amount of hydrogen peroxide, malondialdehyde, superoxide dismutase, peroxidase, proline, and soluble carbohydrates (water and ethanol soluble) and caused the osmotic potential to become more negative. Biochar application decreased the negative effects of drought stress so that hydrogen peroxide, malondialdehyde, superoxide dismutase, peroxidase, proline, and soluble carbohydrates (water and ethanol soluble) amounts were lower than the treatments without biochar. Overall, the present research results proved the useful and effective role of biochar in improving the physiological traits and protective osmolytes of N. sativa under drought stress.

Sesame cake extract is the by-product left behind after sesame oil extraction including almost 30% of protein and phytochemicals, which possess free radical scavenging activity. In this study, antioxidant activity of sesame cake extract on the quality of refined sesame oil has been evaluated under 60 ◦C during storage time.

After extraction of ethanolic extract, sesame oil was treated with concentrations of 0, 20, 50, and 100 ppm of sesame cake extract and stored at 60 °C for 30 days. The sesame cake and refined sesame oil were taken from Yazd province and extracted with ethanol. Total Phenolic Content (TPC) (at the beginning of the study) and 2,2-Diphenyl-1-Picrylhydrazyl (DPPH) radical scavenging capacity (30 days after inoculation) were evaluated. The antioxidant activity of various dilution of the Sesame Cake Ethanol Extract (SCEE) was assessed by measuring, rancimat analysis, Peroxide Value (PV), and Thiobarbituric Acid (TBA) assay, and also evaluation of the TPC. Butylated Hydroxyanisole (BHA) as a synthetic antioxidant was used. Experiments were carried out in triplicates and data were processed with ANOVA test by SPSS Software.

Radical-scavenging capabilities of SCEE were significantly larger than the group without SCEE but it was detected to be lower than the BHA group. The induction period (IP) of sesame oil raised as the concentration of SCEE increased. All concentrations of SCEE were able to decline the PV and TBA value. Also, the group containing BHA and 100 μg/ml of SCEE significantly showed the same antioxidant activity (p≤0.05).

The SCEE as a natural substance can prevent lipid oxidation of the refined sesame oil like synthetic antioxidants.

In fact, drought is stress that restricts the plant photosynthesis and also it causes of chlorophyll content changes and damage to photosynthetic structures. One of the important reasons that environmental stresses such as drought reduce the growth and photosynthesis ability of the plant is a disturbance in the balance between production and removal of free oxygen radicals. Transpiration is a necessary process for photosynthesis and growth of plants but depending on the conditions that may be harmful in some cases. Therefore, the use of anti-transpirant can be one of the most effective methods for reducing the amount of water lost through transpiration and adjustment the reduction of the yield due to water deficiency in arid and semi-arid regions. Climate change happened on earth and the intensification of stresses caused by it, especially drought stress in arid and semi-arid regions such as Iran. Therefore, finding strategies that can reduce the effects of water shortages on plant growth and yield can be very important. The aim of the present study was to investigate the effect of irrigation regimes and application of different concentrations of tragacanth (naturally dried exudate from some Astragalus species) on black cumin plant.   

This research was carried out in a factorial experiment based on completely randomized design with three replications in a greenhouse of the Agriculture College of Kurdistan University in 2018. The experimental factors were including irrigation at three levels of 100% (full irrigation), 70% (mild drought stress), and 40% (severe drought stress) of field capacity of soil and spraying with tragacanth extract at six concentrations of 0, 1.25, 2.5, 5, 7.5, and 10 g/L. Spraying of this material was done using a back sprayer (Shark model) with a constant pressure of 2.4 bar and a volume of 250 liters of water per hectare., The normality test was performed using the Mini Tab software, before the data were analyzed. After ensuring the normality of data, analysis of variance was performed using SAS ver. 9.3. LSD (Least significant difference) was used to compare the mean of treatments. The graphs are drawn using Excel software.   

The results showed that increased drought stress intensity (irrigation reduction) led to the reduced leaf relative water content, Total chlorophyll content, efficiency of photosystem II, plant height, number of capsules per plant, mean number of seeds per plant, biological yield and grain yield. The positive effects of tragacanth consumption on reducing and modifying the effects of drought stress on different levels of irrigation and different concentrations of tragacanth were different. In the present study, under full irrigation conditions, lower concentrations of tragacanth were useful, while in drought stress conditions, higher concentrations of tragacanth (except 10 g/L) were useful. In full irrigation, the concentration of 1.25 g/L was positive for all studied traits. In mild drought stress, the use of higher concentrations of tragacanth up to 5 g/L had the best effect and more concentrations resulted in a reverse effect on studied traits. In severe drought stress, the use of more concentrations of tragacanth extract was beneficial and improved the studied traits up to 7.5 g/L, but 10 g/L had a negative effect on these traits.

The results of this study indicated that the different effects of various concentrations of tragacanth material in different levels of irrigation on studied traits of black cumin. Therefore, it can be concluded that the application of different concentrations of tragacanth gum was completely dependent on the plant's water status. Therefore, using higher concentrations of tragacanth gum in drought stress conditions had a more positive effect on the plant, and vice versa, using a lower concentration of this material was useful in full irrigation. The effect of tragacanth gum on reducing and modifying the effects of drought stress in different plants requires further studies and extensive research. Tragacanth gum can be introduced as a new anti-transpirant agent with natural origin and its application can be useful and recommended in areas exposed to drought stress.

Aflatoxin M1 is one the most important mycotoxin contaminants of milks. Various methods have been described to detect aflatoxins in milks, including chromatography, enzyme-linked immunosorbent assay and colorimetry. Regarding high sensitivity of electrochemical sensor based methods, the aim of the present study was to fabricate an accurate sensitive voltametric biosensor for the rapid detection of aflatoxin M1.

In the present study, a biosensor based on magnetic and gold nanoparticles modified with pencil graphite electrodes was combined with high-performance liquid chromatography to identify aflatoxin M1. Electrochemical behaviors of the biosensor were investigated at various stages of fabrication, including immobilization of magnetic nanoparticles, gold nanoparticles, aptamers and analytics using cyclic voltammetry and electrochemical impedance spectroscopy techniques.

Results showed that the current peak and charge transfer resistance respectively increased and decreased as the nanoparticles were immobilized, while the current peak and charge transfer resistance increased, compared to the unmodified electrode with the aptamer and analytics immobilization. Assessment of the functional characteristics revealed that the biosensor desirable repeatability (4.6%), reproducibility (8.8%) and acceptable stability (14 days). The biosensor limit of detection was 40 ng/l and the recovery proportion range was reported 93.5–89.6 and 102–105 for biosensor and high-performance liquid chromatography, respectively.

The suggested biosensor presented a limit of detection lower than that of Iranian national standard for milk (100 ng/l). Analysis of aflatoxin M1 contaminated milk samples using the biosensor showed a recovery proportion range close to that of high-performance liquid chromatography.

Wheat germ is the most nutritious part of wheat grains, which has a short shelf-life due to its high lipid contents and presence of lipase and lipoxygenase enzymes. Thus, wheat germs are separated from the whole wheat grains during the flouring process, mostly used as animal foods. The objective of this study was to investigate effects of fermentation by Lactobacillus acidophilus and Lactobacillus plantarum on lipase, lipoxygenase activity and antioxidant characteristics of wheat germs.

Various concentrations of wheat germs were inoculated individually with a certain number of the bacteria (109 Log CFU / mL). After incubation at 37 °C for 24 h, pH changes and antioxidant, lipase and lipoxygenase activities were compared to those of unfermented samples and effects of various starters on the highlighted characteristics of wheat germs at various concentrations were investigated.

Fermentation by the two bacteria significantly decreased activities of the lipase and lipoxygenase enzymes. Furthermore, 20% concentration of fermented wheat germs by Lactobacillus plantarum showed the highest decreases in activities of the two enzymes (71/43 for lipase and 65% for lipoxygenase). Raw wheat germs included good antioxidant activities that significantly increased after fermentation by the bacteria. Investigation of the starter type and substrate concentration showed that the highest (29.97%) and the lowest (21.55%) increases in antioxidant activities after fermentation were linked to fermented samples by Lactobacillus plantarum at 20% and Lactobacillus acidophilus at 10% concentrations of wheat germs, respectively.

Fermentation by Lactobacillus acidophilus and Lactobacillus plantarum significantly improves antioxidant activities of the wheat germs and increases its shelf-life by significantly decreasing lipase and lipoxygenase activities.

As a native fermented dairy drink, doogh is an important industrial product in Iran. However, its characteristics have not been completely evaluated. This study evaluated the flow behavior, particle size distribution and stability of non-fat doogh as affected by the row material employed (fresh skim milk or skim milk powder) and the total solids (TS) content of the final drink. The viscosity of samples produced using fresh skim milk was 1.73 ± 0.24cPs. Those produced using skim milk powder exhibited higher viscosity resulting from bigger particle size. Increasing the TS content caused the viscosity of the doogh to increase, but the volume of the separated serum was reduced. Flow behavior became non-Newtonian at higher TS contents. Evaluations indicated that the colloidal particles existing in doogh were distributed among a wide range of sizes. Different particle shapes with complex structures were observed.