جستجوی مقالات مرتبط با کلیدواژه « کاروتنوئیدها » در نشریات گروه « زیست شناسی »

The purpose of this research is to investigate the effect of carotenoids according to the reference of the biology textbook to the antioxidant properties and improving the immune system function in the conditions of the COVID-19 epidemic in order to learn about plant physiology and biotechnology in the field. It is practical. Due to the fact that carotenoids are presented in the textbook under the title of colors in plants in the 10 th grade plant seasons, and usually, due to the nature of plant seasons, students have less connection with these topics than other fields of biology. And considering that the biology teacher should make an effort in the field of active and up-to-date education, especially in communicating the subjects with the environment and the daily life of the learners, in this research, it has been tried to connect one of the subjects in the plant field with another. One of the main topics of the day is to examine the epidemic of COVID-19 . The research method in this article is descriptive and analytical, and according to this issue, in this research, the relationship of carotenoids with strengthening the immune system and examples of the antiviral roles of carotenoids have been investigated by referencing 40 articles in Latin in the spring of 2022. Is. The results of this research showed that carotenoids can target the inflammation caused by viral infections, and diets rich in carotenoids may be factors that prevent the progression of the disease.

In order to study the effects of irrigation and abscisic acid regime on physiological factors and gas exchanges of Lavandula angustifolia CV. Organic Munestead, a pot experiment was conducted as factorial based on randomized complete block design with three replications at Plant Production faculty of Gorgan University of Agricultural Sciences and Natural Resources, during growing season of 2016- 17. The treatments were four levels of irrigation regimes (30-40, 50-60, 70-80 and 90-100 percent field capacity) and Abscisic acid including three levels (0, 15 and 30 Mm/L). The results showed that irrigation regimes increase chlorophyll a, chlorophyll b, chlorophyll a+b, gas exchange and RWC. Abscisic acid had significant effect on all traits except of carotenoid content that except to efficiency of water consumption was Abscisic acid 15 Mm/L, the others were the highest in Abscisic acid 30 Mm/L. Also interaction effect of irrigation regimes and Abscisic acid was significant for all traits except of chlorophyll a+b. Abscisic acid 15 Mm/L spray and irrigation regimes 30-40 percent field capacity increase 25.04 and 38,75 in efficiency of leaf water consumption and efficiency of water consumption, respectively. Generally, Abscisic acid 15 Mm/L application and irrigation regimes 30-40 percent field capacity Introduces the best treatment, due to the lower consumption of water and the use of Abscisic acid in stress conditions, higher levels of Abscisic acid can be achieved in inducing drought tolerance.

The pathway for the synthesis of carotenoids is now well known, but the findings about the regulation of this path are almost limited. Along with the role of pigmentary and essential carotenoids in plants, these compounds also play an important role in human health. Given that the human body does not synthesize carotenoids, it is dependent on carotenoids derived from the diet to produce retinoids such as retinal (important eye pigmentation), retinol (vitamin A), and retinoic acid (the main controller of morphogenesis The main source of retinoids is B-carotene, which is also called vitamin A, and the lack of that night causes blindness and blindness. Recent research has focused on manipulating the content of carotenoids and plant product compounds to increase their nutritional value. Although all known genes in the biosynthesis of carotenoids are encoded by the nucleus of the nucleus, all of the carotenoid pigments and their associated enzymes are in the plastids. Among the encoding genes of carotenoid biosynthesis enzymes, PSY, the catalyst for the first phase of the biosynthetic pathway of carotenoids, is of particular importance. Given the global scarcity of vitamin A deficiency and its harmful effects on human health, and in particular children, scientists have focused on increasing the levels of carotenoids in ornamental plants.

Salt stress is one of the factors limiting plant growth and a major obnstacles for nutrient uptake in plants. A factorial experiment with pots in the open air was implemented based on a completely randomized design with three replications to evaluate the effect of foliar application of iron (Fe: Sequestrene 138 at a concentration of 5 per thousand), boron (B: Boric acid at a concentration of 5 per thousand), and selenium (Se: Sodium selenite at a concentration of 2 per thousand) under NaCl salinity on root growth characteristics and the photosynthetic pigmentscontent of Stevia plant. The experiment factors included different levels of sodium chloride (0, 3, 6, and 9 dS m-1) and spraying composition at eight levels (no spraying, Fe, B, Se, Fe Se, Fe B, Se B, and Fe Se B). Results showed that salinity caused significant reduction in root dry weight, volume, length, diameter and density of root, percentage of dry weight to soil volume ratio, and chlorophyll a, b, and total. Among the various combinations of spraying, combined application of Fe, B, and Se had the highest mean dry weight, volume, length, area, and density of the root. The highest significant mean chlorophyll b and total chlorophyll contents were observed in spraying solution containing Fe at the non-stress level, and the combination of Fe and Se at 3 dS m-1 level of salinity. In general, decrease in root growth and leaf chlorophyll content (especially chlorophyll a) occurred under salt stress and generally, these factors led to the loss of plant growth at higher salinity levels (6 and 9 dS m-1). In order to reduce the negative effects of salinity stress, especially at lower levels (3 and 6 dS m-1), using Fe and Se elements are recommended to increase the chlorophyll content of the plant and improve root growth.

Microorganisms produce carotenoids as a part of their response to environmental stresses. Carotenoids have many applications in human health, such as antioxidant, anti-cancer, light protection activity and as a precursor for hormones.
In this study, the effect of different carbon and nitrogen sources was evaluated on carotenoids production by native Aurantiochytrium strain. The effects of different carbon and nitrogen sources were studied on biomass and carotenoid production. Then, carotenoids were extracted and analyzed by TLC, spectrophotometry and HPLC methods.
Results showed that glycerol is the best carbon source for production of high carotenoids content. Selected medium contained: glycerol (1.5% v/v), peptone (1g/l), yeast extract (1g/l) and 50% of sea water. Total carotenoids content was 134.8 µg/g CDW in this medium. TLC analysis showed that the extracted carotenoid is included: beta-carotene, astaxanthin monoester, astaxanthin diester and free astaxanthin. The results of HPLC analysis showed presence of astaxanthin, canthaxanthin, echinenone and β-carotene in the carotenoid extract.
Discussion and In this research, production of carotenoids was investigated in native strain of Aurantiochytrium and carotenoids profile was included astaxanthin, canthaxanthin, β-carotene and echinenone.

Nitrogen and and phosphorus are important components of plant nutrition. However inappropriate use of these nutrients can affect physiological aspects of plant. Therefore, in order to evaluate the response of some physiological parameters in purslane sucuulent plant to plant nutrition, an experiment was conducted as a RCBD with a split plot in time arrangement, which that nine levels of plant nutrition (T0: control (no fertilizer) T1: N-based broiler litter T2: P-based broiler litter T3: N-based cattle manure T4: P-based cattle manure urea T5: chemical fertilizer equivalent T1 T6: chemical fertilizer equivalent T2 T7: chemical fertilizer equivalent T3 and T8: chemical fertilizer equivalent T4 as a main factor and two levels of harvest date (27 July and 16 August) as sub factor. The results indicated that fertilizer treatments significantly increased chlorophyll a and chlorophyll b content compared to the control (no fertilizer). In the first harvest, the T8 treatment (0.33 mg g-1) showed the lowest carotenoids content, In the second harvest, the lowest carotenoids content was obtained in T2 and T7 treatments (0.43 and 0.45 mg g-1, respectively) which that there were no significant difference among T1 and T3 treatments. Dry matter partitioning of leaf: stem in broiler litter treatments (60.3:39.7) was more balanced than cattle manure treatments (63.6:36.4). Nitrate amount of BL and CM treatments was significant lower than the chemical fertilizer treatments. In general, it can be concluded that purslane photosynthesis and production is more affected by broiler litter application than the chemical fertilizer and cattle manure, which that it causes a considerable increase in crop production and health.

In this experiment، we studied the effects of drought stress under field conditions on chlorophyll a، chlorophyll b، carotenoids، rubisco large subunit (rbsl) and the activities of antioxidant enzymes in barley at early anthesis، watery ripe، late milk and soft dough stages of two genotypes with different yield (Q13:1390 Kg/ha and Q20:1582 Kg/ha). The results showed that under oxidative stress chlorophyll b is more sensitive than chlorophyll a. The amount of cartenoids increased at initial time of stress period، but declined with the progress of stress. The amount of rbsl declined during senescence and drought stress. The activity of SOD declined with plant age in both water treatments. However it was more in plants under drought stress of Q13. APX activity declined with age in both water treatments of Q13. There were no significant difference with age in Q20 APX activity. Drought stress triggered increases in antioxidant enzymes activities. We concluded that Q20 has more ability to maintain SOD activity during water deficit stress and APX activity during senescence; therefore it seems that this ability is a key role for increasing the yield of Q20 in compare to Q13.