The Influence of Different Light Wavelengths on Growth, Enzymes Activity and Photosynthesis of the Marine Microalga Dunaliella parva W.Lerche 1937

يعتبر الضوء عاملاً هامًا يؤثر على نمو الطحالب الدقيقة وكفاءة التمثيل الضوئي لها ؛ ومع ذلك ، لا يُعرف الكثير عن كيفية تأثير شدة الضوء مع الطول الموجي على قدرة التمثيل الضوئي ونمو الطحالب البحرية الدقيقة. في هذه الدراسة ، تمت دراسة نمو الطحالب البحرية الخضراء الدقيقة ديوناليلا بارفا  واقلمته تحت شدة الضوء المختلفة (25 ~ 70 μmol m-2 s-1) ونوعية الضوء (الأزرق والأخضر والأحمر) مقارنة بالضوء الأبيض عند 40 μmol m-2 s-1  كتجربة ضابطة (كنترول). تمت مراقبة النمو عن طريق حساب عدد الخلايا ومحتوى الصبغة وتراكيز Chl a و Chl b والكاروتينات. تم تسجيل النمو الأمثل وأعلى كفاءة التمثيل الضوئي (Fv / Fm) بكثافة ضوء 40 μmol m-2 s-1 ، ضوء أبيض ، و 1.25 مولار كلوريد الصوديوم (. 1.47 and 0.678×106 cell mL-1، على التوالي). أظهر نشاط إنزيمات مضادات الأكسدة ، بما في ذلك الكاتلاز والبيروكسيديز وكذلك محتوى الأسكوربات ، أعلى قيم بلغت 0.190 µM/min.mg Chl, 0.434 and 13.3 mg/g f.wt.  على التوالي ، تحت تأثير  الضوء الأخضر ، الذي أكد وجود ضغوط بيئية.Light is an important factor that influences the growth and photosynthetic efficiency of microalgae; however, little is known about how light intensity together with the wavelength affect the photosynthetic capacity and growth of marine microalgae. In the present study, the growth of the marine green microalga Dunaliella parva was studied and optimized under different light intensities (25 ~ 70 μmol m-2 s-1) and qualities (blue, green, and red) in comparison with white light at 40 μmol m-2 s-1 as a control. The growth was monitored by counting the cell number, pigment content, Chl a, Chl b, and carotenoids concentrations. The optimal growth and highest photosynthetic efficiency (Fv/Fm) were recorded at a light intensity of 40 μ mol m-2 s-1, white light, and 1.25 M NaCl (1.47 and 0.678×106 cell mL-1, respectively). The activity of antioxidant enzymes, including catalase and peroxidase, as well as ascorbate content, showed the highest values of 0.190 µM/min.mg Chl, 0.434 and 13.3 mg/g f.wt. respectively, under the green light, which confirmed the presence of environmental stresses

Evaluation of Polycladia myrica mediated selenium nanoparticles (PoSeNPS) cytotoxicity against PC-3 cells and antiviral activity against HAV HM175 (Hepatitis A), HSV-2 (Herpes simplex II), and Adenovirus strain 2

IntroductionThe trace element selenium is an essential micronutrient for the health of humans, animals, and microbesMany researchers have recently become interested in selenium nanoparticles (SeNPs) because of their biocompatibility, bioavailability, and low toxicity. Consequently, selenium nanoparticles are widely used in various biomedical applications and wastewater bioremediation due to their greater bioactivity. Green biosynthesis of nanoparticles is common and preferable nowadays.MethodsIn this work, the selenium nanoparticles were synthesized using the brown seaweed Polycladia myrica aqueous extract and characterized using seven parameters, SEM, TEM, UV spectra, Zeta potential, EDX, X-ray differaction and FTIR, then examined for their cytotoxicity using PC-3 cells and normal mammalian cells from the African green monkey kidney (Vero) were used to test the effectiveness of the produced Polycladia myrica mediated selenium nanoparticles as an anticancer agent and antiviral activity against HAV HM175 (Hepatitis A), HSV-2 (Herpes simplex II), and Adenovirus strain 2.ResultsThe phycosynthesized nanoparticles exhibit antiviral activity (40.25 ± 2.61, 8.64 ± 0.82, and 17.39 ± 1.45%) against HAV-10, Adenovirus, and HSV-2, respectively. The IC50 values of the two cell types human prostate PC-3 and Vero were 123.51 ± 4.07 g/mL and 220.53 ± 6.89 g/ mL, respectively. The maximum inhibitory percent was 86.15 ± 2.31 against PC-3 cells. At the same time, at a concentration of 125 g/mL.DisscusionThis work showed that PoSeNPS have good antiviral activity against HAV-10 virus with an antiviral percent of 40.25%, despite weak antiviral activity against Adenovirus and HSV-2 with antiviral percent (8.64% and 17.39%), respectively. The cytotoxicity effect of these nanoparticles was determined against PC-3 with a maximum inhibitory percent of 80.53%. These nanoparticles have no hazardous effect against normal Vero cells as the viability percent was (78.39% and 49.23%) for Vero cells and PC-3 cells, respectively, at 125 μg/mL

Protective effects of Spirulina on the liver function and hyperlipidemia of rats and human

In the present study, the effects of Spirulina on subchronic treatments (two weeks) of hyperlipidemia and liver function of the rats and humans were investigated. The hyperlipidemia was induced in the rats using 25% of soya bean oil and 25% butter. The butter induced more hyperlipidemia than soya bean oil. Spirulina was used at the concentrations of 0, 2.5, 5.0 and 10 % of diet weight of the rats. The decrease in hyperlipidemia by Spirulina was dependent on its concentration in the diet. In case of human studies, about four g/day of Spirulina was taken via oral administration by Egyptian volunteers patients with hyperlipidemia. Spirulina decreased the levels of hyperlipidemia in these patients. The effects were dependent on the amount and number of administered dose of Sprirulina. The results suggested that the Spirulina treatment could induce marked reduction of aminotransferase through correcting lipid profile and increasing high density lipoprotein

Biosynthesis of cellulose from Ulva lactuca, manufacture of nanocellulose and its application as antimicrobial polymer

Abstract Green nanotechnology has recently been recognized as a more proper and safer tool for medical applications thanks to its natural reductions with low toxicity and avoidance of injurious chemicals. The macroalgal biomass was used for nanocellulose biosynthesis. Algae are abundant in the environment and have a high content of cellulose. In our study, we extracted parent cellulose from Ulva lactuca where consecutive treatments extracted cellulose to obtain an insoluble fraction rich in cellulose. The extracted cellulose has the same results obtained by matching it with reference cellulose, especially the same Fourier transform infrared (FTIR) and X-Ray diffraction (XRD) analysis peaks. Nanocellulose was synthesized from extracted cellulose with hydrolysis by sulfuric acid. Nanocellulose was examined by Scanning electron microscope (SEM) shown by a slab-like region as Fig. 4a and Energy dispersive X-ray (EDX) to examine the chemical composition. The size of nanocellulose in the range of 50 nm is calculated by XRD analysis. Antibacterial examination of nanocellulose was tested against Gram+ bacteria like Staphylococcus aureus (ATCC6538), Klebsiella pneumonia (ST627), and Gram-negative bacteria such as Escherichia coli (ATCC25922), and coagulase-negative Staphylococci (CoNS) to give 4.06, 4.66, 4.93 and 4.43 cm as respectively. Comparing the antibacterial effect of nanocellulose with some antibiotics and estimating minimal Inhibitory Concentration (MIC) of nanocellulose. We tested the influence of cellulose and nanocellulose on some fungi such as Aspergillus flavus, Candida albicans, and Candida tropicalis. These results demonstrate that nanocellulose could be developed as an excellent solution to these challenges, making nanocellulose extracted from natural algae a very important medical material that is compatible with sustainable development

Green technology for bioremediation of the eutrophication phenomenon in aquatic ecosystems: a review

Eutrophication is a serious phenomenon that leads to vigorous algal blooms that alters the structure of ecosystems.  It is caused by non-point sources of nutrients; as nitrogen and phosphorus, and point sources as wastewater effluent.  Distinctive algae groups are responsible for this phenomenon, such as diatoms, blue-green algae, green algae, and  dinoflagellates. Numerous solutions have been considered to control eutrophication and harmful algal blooms such  as the biological removal of nitrogen and phosphorus. Advanced treatments (i.e. green technology) depend upon  the remediation of wastewater before discharge, such as the removal of phosphorus using agricultural waste-based biosorbents (AWBs) from water and wastewater, and phosphorus sorption performance by both unmodified and modified AWBs. Phyto-remediation includes many procedures that encompass the cost-effective and environmentally friendly methods used to remove or reduce excess natural/inorganic contaminants in groundwater, surface water, and soil. Due to the rapid growth of duckweeds and their ability to rapidly remove minerals as phosphates and nitrogen from  the water, duckweed may be the most promising plant for controlling eutrophication and, therefore, harmful algal blooms

Efficacy of microencapsulated lactic acid bacteria in Helicobater pylori eradication therapy

Background: Probiotic delivery systems are widely used nutraceutical products for the supplementation of natural intestinal flora. These delivery systems vary greatly in the effectiveness to exert health benefits for a patient. This study focuses on providing probiotic living cells with a physical barrier against adverse environmental conditions. Materials and Methods: Microencapsulation of the selected lactic acid bacteria (LAB) using chitosan and alginate was performed. Physical examination of the formulated LAB microcapsules was observed using phase contrast inverted microscope and scanning electron microscope (SEM). Finally, the survival of microencapsulated and noncapsulated bacteria was cheeked in the simulated human gastric tract (GT). The potential antimicrobial activity of the most potent microencapsulated LAB strain was in vivo evaluated in rabbit models. Results: Microencapsulated L. plantarum, L. acidophilus, and L. bulgaricus DSMZ 20080 were loaded with 1.03 × 10 10 CFU viable bacteria/g, 1.9 × 10 10 CFU viable bacteria/g, and 5.5 × 10 9 CFU viable bacteria/g, respectively. The survival of microencapsulated cells was significantly higher than that of the free cells after exposure to simulated gastric juice (SGJ) at pH 2. Additionally, in simulated small intestine juice (SSJ), larger amounts of the selected LAB cells were found, whereas in simulated colon juice (SCJ), the released LAB reached the maximum counts. In vivo results pointed out that an 8-week supplementation with a triple therapy of a microencapsulated L. plantarum, L. acidophilus, and L. bulgaricus DSMZ 20080 might be able to reduce H. pylori. Conclusion: Microencapsulated probiotics could possibly compete with and downregulate H. pylori infection in humans

Bioremediation of malachite green dye using sodium alginate, Sargassum latifolium extract, and their silver nanoparticles

Abstract Introduction The textile, paper, rubber, plastic, leather, cosmetics, pharmaceutical, and food sectors extensively use malachite green (MG). In spite of this, it has mutagenic, carcinogenic, teratogenic, and, in some circumstances causes chronic respiratory disease. Objectives In this work, we used sodium alginate, Sargassum latifolium aqueous extract, and their silver nanoparticles to test their potential as inexpensive adsorbent agents to remove malachite green dye from aqueous solutions. Methods The removal rate of MG was determined using a series of bioadsorption experiments. Besides, the effect of different factors on bioadsorption, such as pH, adsorbent dose, contact time (min), and different concentrations of MG dye was investigated. Results The removal efficiency of MG dye by alginate nanoparticles, alginate, Sargassum latifolium aqueous extract, and S. latifolium aqueous extract nanoparticles was 91, 82, 84, and 68 respectively. The optimal conditions for bioadsorption of malachite green dye were pH 7, a contact time of 180 min, and an adsorbent dose of 0.02 g. The adsorption isotherm was fitted to Langmuir and Freundlich isotherm. Also, UV and FT–IR before and after the bioadsorption of MG were performed to confirm the bioadsorption process. Conclusion Our results indicated that alginate nanoparticles were the most effective bioadsorbent agent

Effect of Cyanobacteria Isolates on Rice Seeds Germination in Saline Soil

Cyanobacteria are prokaryotic photosynthetic communities which are used in biofertilization of many plants especially rice plant. Cyanobacteria play a vital role to increase the plant's ability for salinity tolerance. Salinity is a worldwide problem which affects the growth and productivity of crops. In this work three cyanobacteria strains (Nostoc calcicola, Anabaena variabilis, and Nostoc linkia) were isolated from saline soil at Kafr El-Sheikh Governorate; North Egypt. The propagated cyanobacteria strains were used to withstand salinity of the soil and increase rice plant growth (Giza 178). The length of roots and shoot seedlings was measured for seven and forty days of cultivation, respectively. The results of this investigation showed that the inoculation with Nostoc calcicola, Anabaena variabilis, and Nostoc linkia increased root length by 27.0, 4.0, 3.0 % and 39, 20, 19 % in EC5 and 10 (ds/m), respectively. Similarly, they increased shoot length by 121, 70, 55 %, 116, 88, 82 % in EC5 and 10 (ds/m), respectively. In EC15and more concentrations, control rice plants could not grow while those to which cyanobacteria were inoculated could withstand only EC15 but not other elevated concentrations. These results encourage using Nostoc calcicola,Anabaena variabilis, and Nostoc linkia as biofertilizer for rice plant in the saline soil for increasing growth and decrease soil electrical conductivity