scholarly journals Characterization and Impact of Silver nanoparticles on cell growth, lipid, carbohydrate and fatty acids of Chlorella vulgaris and Dictyochloropsis splendida

2019 ◽  
Author(s):  
Sanaa Mahmoud Metwally Shanab ◽  
Abir M Partila ◽  
Hamdy Elsayed Ahmed Ali ◽  
Mohd A Abdullah

Background: Many efforts have been made to increase the productivity of microalgae for biodiesel productions. The use of silver nanoparticles is the novel way to elicit stress responses with enhanced lipid level. Results: In this study, the biosynthesis of extracellular silver nanoparticles (AgNPs) was reported and their impacts as elicitors on the cell growth and metabolite contents of Chlorella vulgaris and Dictyochloropsis splendida were evaluated. The production of AgNPs was achieved by the reduction of silver nitrate (AgNO3) solution, after incubation at 35°C overnight with Pseudomonas aeruginosa supernatant, and exposed to gamma irradiation at 100 Gy for 1.5 mins. The biosynthesis was confirmed by the maximum absorption peak at 455 nm with the UV–Vis Spectrophotometer. The Atomic Force Microscopy (AFM) recorded the spherical nanoparticles size of 10 nm, while the Dynamic Light Scattering (DLS) recorded the size range of 6.7 to 12.1 nm (84.2%) and the particles were monodispersed. The Gas Chromatography/Mass Spectroscopic analysis of the bacterial filtrate before reaction with AgNO3 suggested the presence of ethylene glycol derivatives which may act as a reducing agent of silver ions to silver nanoparticles. Lower AgNPs concentrations (1, 3 and 5 mg/L) enhanced the lipid production but at the expense of cell growth. All AgNPs concentrations however displayed a negative impact on carbohydrates content. The lipid profile of the AgNPs-treated algae showed the appearance or disappearance, and increase or decrease of certain fatty acids, as compared to the untreated control. The Saturated Fatty Acids represented the highest composition (61-67%) of the total fatty acids and Palmitic acids (16:0) were dominant (43.06-46.57%). Conclusion: Lipids of this composition could withstand autoxidation during storage and are perfect feedstock for biodiesel and other lipid based applications.

2019 ◽  
Vol 7 (4.14) ◽  
pp. 221
Author(s):  
S. N. Ibrahim ◽  
K. A. Radzun ◽  
K. Ismail

Chlorella vulgaris is one of the promising microalgae strains that can produce high yield of bio-oils. The C. vulgaris was pretreated with microwave irradiation prior to extraction using supercritical carbon dioxide (SCCO2). Fourier transform infrared spectroscopy (FTIR) analysis showed microwave irradiation pretreatment does not affect the material composition of C. vulgaris. Scanning electron microscopy (SEM) of the microwave irradiation pretreated microalgae showed an agglomeration of the cells with the cells shape became distorted due to rupturing of the cell walls. Optimization of the SCCO2 process parameters (pressure, temperature and CO2 flow rate) was performed by using response surface methodology (RSM) with central composite design (CCD). Two factors significantly affecting the extraction yield were temperature and pressure. The model equation also predicted the optimum condition for the SCCO2 (without microwave pretreatment) at 70 , 5676 psi and 7 sL/ min while optimum condition for SCCO2 (microwave irradiation pretreatment) at 63 , 5948 psi and 10 sL/ min. High amount of saturated fatty acids (SFA), monounsaturated fatty acids (MUFA), -linolenic acid and palmitoleic acid were found in the extracted oil with microwave irradiation pre-treatment sample.  In addition, the polyunsaturated fatty acids (PUFA) content in the microwave irradiation pretreated oil was considerably low and is desirable for biodiesel production. 


2005 ◽  
Vol 2005 ◽  
pp. 162-162
Author(s):  
B. Navidshad ◽  
M. Shivazad ◽  
A. Zare Shahneh ◽  
G. Rahimi

Fat saturation degree and the age of bird are two important factors for broilers’ ability to digest fats. It has been shown that hepatic fatty acid synthetase activity is decreased by diets with added sunflower oil (rich in PUFA of n-6 series) compared with those fed lard and this can result in abdominal fat pad reduction. (Sanz et al., 2000). It is well known that dietary intake of n-6 and n-3 PUFAs is effective in lowering blood lipid level, but they differ in their effect on serum lipid concentrations. It has been observed that n-6 fatty acids lower serum cholesterol level, but not triacylglycerol; n-3 fatty acids lower both serum cholesterol and serum triacylglycerol level in experimental animals (Berr et al., 1993). The objective of this study was to survey the effects of different dietary unsaturated to saturated fatty acids ratio on performance, abdominal fat pad and serum lipids in broiler chickens.


Marine Drugs ◽  
2019 ◽  
Vol 17 (8) ◽  
pp. 484 ◽  
Author(s):  
Thanapa Atikij ◽  
Yolani Syaputri ◽  
Hitoshi Iwahashi ◽  
Thanit Praneenararat ◽  
Sophon Sirisattha ◽  
...  

Microalgal lipids are a source of valuable nutritional ingredients in biotechnological industries, and are precursors to biodiesel production. Here, the effects of salt-induced stresses, including NaCl, KCl, and LiCl stresses, on the production of lipid in green microalga Chlamydomonas reinhardtii (137c) were investigated. NaCl stress dramatically increased saturated fatty acids (SFAs), which accounted for 70.2% of the fatty acid methyl ester (FAMEs) under stress. In contrary, KCl stress led to a slight increase in SFAs (47.05%) with the remaining being polyunsaturated fatty acids (PUFAs) (45.77%). RT-PCR analysis revealed that the genes involved in FA biosynthesis, such as PDH2, ACCase, MAT and KAS2, were up-regulated by NaCl-induced stress. Conversely, the genes responsible for the Kennedy pathway were suppressed. The alteration of FA homeostasis was further assessed by overexpressing MAT, the enzyme responsible for the production of malonyl-ACP, a key building block for FA biosynthesis, in the cyanobacterium Synechococcus elongatus PCC 7942. Intracellular FA composition was affected, with a predominant synthesis of SFAs in transformed cells. Owing to the diversity and relative abundance of SFAs, monounsaturated fatty acid (MUFAs) and PUFAs enable the feasibility of using microorganisms as a source of microalgal lipids or valuable nutritional ingredients; salt-induced stress and expression of MAT are useful in providing precursors for enhanced lipid production.


Life ◽  
2020 ◽  
Vol 10 (9) ◽  
pp. 204
Author(s):  
Leila Motlagh Scholle ◽  
Helena Schieffers ◽  
Samiya Al-Robaiy ◽  
Annemarie Thaele ◽  
Diana Lehmann Urban ◽  
...  

It is known that exposure to excess saturated fatty acids, especially palmitate, can trigger cellular stress responses interpreted as lipotoxicity. The effect of excessive free fatty acids on oxidative phosphorylation capacity in myoblasts of patients with the m.3243A>G mutation was evaluated with the mitochondrial (Mito) stress test using a Seahorse XF96 analyzer. ß-oxidation, measured with the Seahorse XF96 analyzer, was similar in patients and controls, and reduced in both patients and controls at 40 °C compared to 37 °C. Mito stress test in the absence of fatty acids showed lower values in patients compared to controls. The mitochondrial activity and ATP production rates were significantly reduced in presence of palmitate, but not of oleate in patients, showing a negative effect of excessive palmitate on mitochondrial function in patients. Diabetes mellitus is a frequent symptom in patients with m.3243A>G mutation. It can be speculated that the negative effect of palmitate on mitochondrial function might be related to diacylglycerols (DAG) and ceramides (CER) mediated insulin resistance. This might contribute to the elevated risk for diabetes mellitus in m.3243A>G patients.


2010 ◽  
Vol 29 (4) ◽  
pp. 492-500 ◽  
Author(s):  
Kevin A. Harvey ◽  
Candace L. Walker ◽  
Thomas M. Pavlina ◽  
Zhidong Xu ◽  
Gary P. Zaloga ◽  
...  

2020 ◽  
Vol 11 (2) ◽  
pp. 214-219
Author(s):  
L. L. Yuskiv ◽  
I. D. Yuskiv

The changes in total lipids, their fatty acid composition and the ratio of individual classes were established in tissues of the intestine, hepatopancreas and skeletal muscles of carp (Cyprinus carpio Linnaeus, 1758), with body weight 14.5–20.5 g, at different rates of invasion by Bothriocephalus acheilognathi (Yamaguti, 1934) helminth, which belongs to the family Bothriocephalidae, of the Pseudophyllidae order, of the Cestoda class. The examined carp was divided into three groups: first group of fish was free from intestinal helminths of B. acheilognathi (control); second group of fish was weakly infected with helminths (intensity of invasion is 1–3 helminths per fish); the third group of fish was highly infected (the invasion intensity is 4 worms and more per fish). Our results showed that fish infected with helminth B. acheilognathi compared to uninfected fish had reduced total lipid level in the gut due to phospholipids, triacylglycerols, and also lipids were characterized by lower content of linoleic, linolenic, arachidonic, penta- and hexanoic fatty acids; decrease in the level of unsaturated and increase in the content of saturated fatty acids, which leads to an increase of the saturation factor. During the infection of carp with B. acheilognathi in the hepatopancreas, the content of total lipids, structural lipids – phospholipids and reserve energy sources – triacylglycerols is probably reduced, and lipids are characterized by a high content of saturated fatty acids (С14:0, С16:0, С18:0) and lower content of unsaturated: arachidonic (С20:4), linolenic (С18:3) and linoleic acid (С18:2), which is associated with a decrease in the source for the synthesis of a number of polyunsaturated fatty acids, especially docosahexaenoic (С22:6). The total content of lipids, triacylglycerols, free fatty acids and phospholipids in skeletal muscle of carp during the Bothriocephalus invasion decreased and the content of free cholesterol, mono- and triacylglycerols increased. Helminth B. acheilognathi has the effect of reducing the total lipids of the skeletal muscle content of С18-, С20-, С22-polyunsaturated fatty acids and increasing the content of saturated (С14:0, С16:0, С18:0) and monounsaturated (С16:1, С18:1) fatty acids. The obtained results prove that the parasite B. acheilognathi in the intestine of the carp significantly affects the nutrition processes of the host depending on the intensity of the damage by helminths, which is accompanied by impaired lipid metabolism.


Reproduction ◽  
2010 ◽  
Vol 139 (6) ◽  
pp. 1047-1055 ◽  
Author(s):  
K Bender ◽  
S Walsh ◽  
A C O Evans ◽  
T Fair ◽  
L Brennan

There has been a marked decline in the fertility of dairy cows over the past decades, and metabolomic analysis offers a potential to investigate the underlying causes. Metabolite composition of the follicular fluid, which presents the intrafollicular environment, may be an important factor affecting oocyte maturation and subsequent early embryo development. The aim of the present study was to investigate the metabolic differences between follicular fluid from the dominant follicle of lactating cows and heifers using gas chromatography mass spectrometry (GC–MS)-based metabolomics. Follicular fluid and serum were collected from cows and heifers over three phases of follicle development: newly selected dominant follicles, preovulatory follicles prior to oestrus and post-LH surge follicles. Analysis of the fatty acids revealed that there were 24 fatty acids and 9 aqueous metabolites significantly different between cows and heifers. Of particular interest were the higher concentrations of saturated fatty acids (palmitic acid, P=0.001; stearic acid, P=0.005) in follicular fluid from cows and higher docosahexaenoic acid levels (P=0.022) in follicular fluid from heifers. Analysis of the metabolite composition of serum revealed that follicular fluid had a unique lipid composition. The higher concentrations of detrimental saturated fatty in cows will have a negative impact on oocyte maturation and early embryo development. Overall, the results suggest that the follicle microenvironment in cows potentially places their oocytes at a developmental disadvantage compared with heifers, and that this may contribute to well-characterised differences in fertility.


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