Effect of temperature and light spectrum on the Lutein and Beta-carotenoids production in Chlorella vulgaris algae

Algae contain carotenoids as granules that give them red, orange, or yellow hues. ?-carotene acts as an antioxidant, protecting the body from free radicals, enhancing the immune system, and contributing to cell growth and differentiation. Lutein is a carotenoid found in plants and phototrophic microorganisms. Lutein is widely used as a nutraceutical for human health. This study aimed to investigate the impact of temperature (20, 25, and 30°C) and the light spectrum (red, blue, and white) on the production of lutein and ?-carotene in Chlorella vulgaris. A special incubator cabin was designed for the study, containing three sections: the first part, corresponding to the red spectrum, had an illumination intensity of 152 µmol/m²/s; the blue spectrum had an illumination intensity of 1194 µmol/m²/s; and the white spectrum had an illumination intensity of 303 µmol/m²/s. Four replicates were prepared for each treatment, and two samples were drawn for lutein and ?-carotene pigments on the 9th and 18th days. The results showed that the lutein concentrations ranged between <0.001-5.27 µg/ml at 25°C in the white and blue spectrums, respectively, while the highest concentrations of lutein were at 25°C in the blue spectrum on the 9th day. The results also indicated that the highest concentration of ?-carotene at 20°C was 9.2 µg/ml in the blue spectrum on the 18th day. The study concluded that the best concentrations of lutein production were at 25°C in the blue spectrum on the 9th day, while the best concentrations of ?-carotene production were at 20°C in the blue spectrum on the 18th day of the experiment

Effects of environmental parameters on diatoms community of the Euphrates River system

A study was designed to (1) establish the taxonomy of diatom species in the Euphrates River, and (2) determine the effect of the main environmental factors on diatom community distribution in the Euphrates River. From 14 sites along part of the Euphrates River, samples of diatoms and water were taken during 2016. Diatom samples were collected from the water by phytoplankton nets at a randomly selected site. A total of 96 diatom species were recorded during the study period. Using correlation factor analysis, patterns of diatom species distributions in connection to environmental variables were discovered. Temperature, total suspended solids, total alkalinity, and phosphate (PO4) were all significantly and strongly linked with diatom species in both habitats (r = 0.85, 0.88, 0.92, and 0.83, respectively). Fragilaria crotonensis Kitton 1869 had a higher total number recorded (881.64 cells/l×103) during the study period, and site 2 had a higher total number compared with other sites (4845 cells/l×103). November had a higher total number recorded compared with other months (13722.64 cells/l×103). As a result, we concluded that in lotic systems, environmental conditions can affect the existence and distribution of diatoms

Can aquatic plant (Eichhornia crassipes) be used as a partial substitute for carp fish feed?

This study was conducted to evaluate the possibility of using Eichhornia crassipes as a partial substitute for vegetarian meals to reduce the cost of feeding fish. Eichhornia crassipes powder was included in fish feed at different levels (0%, 25%, 50%, 75% and 100%), and it was fed in Cyprinus carpio L. farms using plastic container for 45 days. The obtained results showed that the final weight gain and specific growth rate (SGR) was (15.83; 9.8) gm respectively in the first treatment during the 45th day, highest percentage compared to the control treatment. Non-Significant differences were observed between treatments and days in feeding fish at p˃0.05 compared with the control treatment. The average intestines length of fish shows the highest increase in the first treatment compare to control, and it may be the best criterion for growth with this concentration. We conclude that the E. crassipes (25%) can be replaced as a partial substitute for meals. Therefore, experiments at other concentrations of lower than 25% are recommended to reach the best growth standards

Compared cadmium adsorption from biochar and magnetite biochar in water

Water safety is a prerequisite for sustainable global quantitative and qualitative development. Heavy metal pollution has become a major problem in our environment, where traditional heavy metal processing techniques were unsuccessful and expensive. In this study, biochar and magnetite biochar have been used as an efficient, low-cost, safe, and environmentally friendly method for heavy metal removal such as cadmium. The biochar has been prepared from palm fronds and then activated by sodium hydroxide before treatment with two concentrations (5 ppm and 10 ppm) of cadmium in the water. The biochar (BC) had a positive effect on improving the efficiency of removing cadmium (II). The percentage to remove cadmium was 98% when we added 0.5 g of biochar to the solution. On the other hand, we have prepared composite materials by mixing biochar with magnetite at the mole ratio of (2:1) to prepare magnetite-biochar (MBC). A property was added to the biochar prepared by adding Fe3O4 to the biochar, which led to the activation of the effective aggregates with a significant improvement in the adsorption performance of heavy metals while increasing the removal efficiency up to 100%

HEAVY METAL BIOREMEDIATION BY ALGAE: A REVIEW OF REMOVAL METHODS, BY-PRODUCT RECOVERY, OBSTACLES, AND POTENTIAL FUTURE APPLICATIONS.

         Due to the constant discharge of many pollutants into the aquatic environment, water pollution is a major environmental concern on a global level. The treatment of heavy metals found in wastewater has attracted attention to novel technologies in recent years. The utilization of biological processes has been investigated because they are dependable, straightforward, and eco-friendly. Through this review, the researchers attempt to disseminate information regarding the environmental dangers posed by heavy metals, the function of bioremediators employed in heavy metal processing, the many microalgae strains utilized for heavy metal removal, and their modes of action for remediation. Different external and intracellular processes are used by diverse microalgae species to remove heavy metals. In-depth discussion is provided on the assessment of microalgae's processing potential and the usage of biochar generated from algae in the removal of heavy metals. It is obvious that bioremediation of heavy metals alone is not a viable business plan. As a result, additional work is being done to create integrated treatment plans to make this procedure more affordable and long-lasting. This review describes recent developments in the use of microalgae for heavy metal therapy. Additionally, the challenges that must be met in order to improve this process efficiency, economy, sustainability, and cleanliness are covered. From the comments in this review, it can be inferred that bioremediation can be crucial to the sustainable processing of heavy metals and the development of the bio-economy