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Cardiovascular Disease and Oxidative Stress
Published in Peter Grunwald, Pharmaceutical Biocatalysis, 2019
Marco Fernandes, Alisha Patel, Holger Husi
Arachidonic acid (AA) is a poly-unsaturated fatty acid that is important for metabolism, specifically for the synthesis of prostaglandins, thromboxanes and leukotrienes (Elinder and Liin, 2017). It is specific to the body’s muscles, liver and brain. AA has the ability control the permeability of cell membranes which then influences different proteins involved with cellular signaling (Piomelli, 1993). AA helps in maintaining cell integrity and vascular permeability, making it important for development and growth upon cell damage occurrence. As a major constituent of membrane phospholipids, it becomes detached from membranes through enzymatic cleavage by phospholipase A2 (PLA2) (O’Donnell et al., 2009), and then can be used as substrate by LOX and P450 hydroxylases to generate superoxide and hydroxyeicosatetraenoic acid (HETE) (Chawengsub et al., 2009).
Nanomedicines for Ocular NSAIDs: State-of-the-Art Update of the Safety on Drug Delivery
Published in Lajos P. Balogh, Nano-Enabled Medical Applications, 2020
Joana R. Campos, Joana Araújo, Elisabet Gonzalez-Mira, Maria A. Egea, Elena Sanchez-Lopez, Marta Espina, Selma B. Souto, Maria L. Garcia, Eliana B. Souto
Being the most sensory organs of the body, diseases affecting eye makes the coloured world into blurred or dark in nature [23]. Ocular discomforts involve anterior/posterior-segment diseases, symptomatic distress, associated inflammation and severe retinal disorders [24]. The inflammation refers to a typical reaction of cells/tissue in response to injury or any other disease condition. It is the kind of reciprocal attempt of the body’s immune system to eradicate foreign bodies or microbes to retard further injury and can be resulted into swelling, redness, heat, and pain. Inflammation is the outcome of imbalance of biochemical homeostasis of the eyes [25]. Inflammatory diseases of the eye such as iritis, uveitis and eye inflammation caused due to an eye injury, allergens, chemical exposure like acids, pesticides or any other harmful chemicals from manufacturing processes in industries. These may further lead to complications like clouding in the retina, the formation of cataracts, an increase of intraocular pressure such as glaucoma and swelling or detachment of the retina [24]. Uveitis is an inflammatory ailment of the eye, which is caused by autoimmunity, infectious organisms, toxic material, or tumours. It could lead to severe pain and increased light sensitivity in the affected patients. Although inflammation is a natural defensive phenomenon, it results in discomfort in the eye and also makes the eye vulnerable to other diseases [26]. Ocular inflammation is also a common result of cataract surgery, producing pain and photophobia in many patients and potentially leading to serious complications including increased intraocular pressure (IOP), posterior capsule opacification, cystoids macular oedema (CME) and decreased visual acuity [27]. This mechanism leads to the stimulation of some membrane protein such as phospholipase A2, following tissue injury/damage, breaks down cell membrane phospholipids to arachidonic acid, which forms the substrate for further reactions mainly by the cyclo-oxygenase and the lipoxygenase pathways. The resulting arachidonic acid metabolites, along with other chemical mediators, interact to cause inflammation.
Biomolecules from Microalgae for Commercial Applications
Published in Kalyan Gayen, Tridib Kumar Bhowmick, Sunil K. Maity, Sustainable Downstream Processing of Microalgae for Industrial Application, 2019
Meghna Rajvanshi, Uma Shankar Sagaram, G. Venkata Subhash, G. Raja Krishna Kumar, Chitranshu Kumar, Sridharan Govindachary, Santanu Dasgupta
Microalgal lipids consist of phospholipids, glycolipids (glycosyl glycerides) and non-polar glycerolipids (neutral lipids). Chain length and degree of unsaturation in microalgal lipids are significantly higher than lipids from plants. Phospholipids (PL) represent 10% to 20% of total lipids in algae (Dembitsky and Rozentsvet 1990; Dembitsky 1996) and are located in extra-chloroplast membranes in significant amounts and maintain the structural integrity of the photosynthetic apparatus. Glycolipids contain 1,2-diacyl-sn—glycerol moiety with mono- or oligosaccharide groups at the sn-3 position of the glycerol backbone. Monogalactosyldiacylglycerol (MGDG), digalactosyldiacylglycerol (DGDG), sulfolipids and sulfoquinovosyldiacylglycerol (SQDG) are the typical glycolipids. Glycolipids are strictly restricted to the thylakoid membranes of the chloroplast. Glycerolipids consists of a glycerol backbone to which acyl groups (hydrophobic) are esterified to either one, two or all three positions. Acyl groups may be saturated or unsaturated, forming mono-, di- and TAG. TAG is the neutral lipids that accumulate in algae as a storage and energy reservoir (Fan et al. 2007; Kulikova and Khotimchenko 2000). Apart from TAGs, many oleaginous algae exhibit the potential to accumulate long-chain PUFAs, namely arachidonic acid, eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA). Parietochloris incisa accumulates arachidonic acid; Phaeodactylum tricornutum, Porphyridium cruentum, Nitzschia laevis and Nannochloropsis sp. accumulate EPA; Pavlova lutheri accumulates both arachidonic acid and EPA; and Schizochytrium mangrovei and Isochrysis galbana accumulate DHA (Chen, Jiang, and Chen 2007; Khozin-Goldberg and Boussiba 2011; Patil et al. 2007). Long-chain PUFAs offer several health benefits; for instance, they contribute in reducing chances of cardiovascular diseases, diabetes, hypertension and autoimmune diseases. DHA plays a positive role in visual and neural health. Arachidonic acid and EPA are precursors of bioregulators, such as prostaglandins, thromboxane and other eicosanoids, which influence inflammatory processes and immune reactions (Calder and Grimble 2002). Lang et al. (2011) screened about 2,071 strains, and their study revealed that taxonomic groups belonging to glaucophytes, rhohophytes, eustigmatophytes and phaeophytes are rich sources of arachidonic acid and EPA. Similarly, other taxonomic groups belonging to haptophytes and dinophytes are rich in EPA and DHA, euglenoids in arachidonic acid and DHA, xanthophytes in arachidonic acid and cryptophytes in EPA (Lang et al. 2011).
Effects of hesperidin on anti-inflammatory and antioxidant response in healthy people: a meta-analysis and meta-regression
Published in International Journal of Environmental Health Research, 2022
Yusuf Buzdağlı, Cemre Didem Eyipınar, Fatma Necmiye Kacı, Aslıhan Tekin
Arachidonic acid is produced by the enzyme phospholipase A2 (PLA2), a phospholipid located in plasma membranes, and is processed by cyclooxygenase (COX) and lipoxygenase (LOX) as part of the inflammatory response. Flavonoids may impede arachidonic acid metabolism enzymes, decreasing the release of inflammatory mediators generated by this pathway. Inhibition of enzymes that cause the release of arachidonic acid, which is released at the beginning of inflammation, indirectly prevents inflammation (Hanáková et al. 2017; Kumar et al. 2017; González Mosquera et al. 2018).
Effects of natural antioxidants on the oxidative stability of waste cooking oil biodiesel
Published in Biofuels, 2021
Nagarajan J., Bose Narayanasamy
Investigation of Capsicum annuum L. was investigated for its antioxidant activity and free radical scavenging ability employing the DPPH method. In spite of the carcinogenic activity of synthetic antioxidants, natural antioxidants are preferred. The presence of antioxidants in C. annuum L. prevent oxidative damage induced by free radicals and reactive oxygen and protect the food or body from oxidative damage [15]. Watermelon known as Citrulluslanatus belongs to the family of Cucurbitaceae possesses antioxidant activity. The DPPH radical scavenging activity of A- Hexane, chloroform and ethanol extracts of Citrulluslanatus were investigated and compared with ascorbic acid. The reducing power increase with the increase in the concentration of extracts among which A- Hexane extract possesses the highest antioxidant activity in vitro [16]. The proximate analysis of watermelon seed shows moisture content in the range of 7.40–8.50%, fat 26.50–27.83%, protein, 16.33–17.55%, fiber, 39.09–43.28%, ash, 2.00–3.00%, carbohydrate, 9.55–15.32% and energy content of 11 kcal/100g. The constituents present in watermelon seeds include saponin, tannins, triterpenoids, glycosides, and alkoids. The findings show the presence of phenolic and antioxidant activity [17]. The production cost of biodiesel is 1.5 times higher than that of diesel fuel in spite of the high cost of vegetable oil that leads to 75% of manufacturing cost. Also, the total manufacturing cost of biodiesel is significantly reduced since Waste Cooking Oil (WCO) is 2 to 3 times cheaper than vegetable oils. The conversion of waste cooking oil into biodiesel cut down the environmental effect of its harmful disposal [18]. Groundnut oil also known as arachis oil is an organic material obtained from groundnuts that possess aroma and taste of its present legume. Groundnut has a high smoke point when compared to other cooking oils. The major constituents of groundnut oil include oleic acid (46.8% as olein), linoleic acid (33.4% as linolein) and palmitic acid (10% as palmilin). It also contains stearic acid, arachidic acid, arachidonic acid, behenic acid, lignoceric acid, and other fatty acids. The production of biodiesel involves the combination of alcohol, oil, and catalyst in an agitated reactor with a reaction temperature of 60 °C for about 1 h [19]. Biodiesel obtained from sunflower seed contributes to 80% of Europe's biofuel production. Waste cooking oil from restaurants contains a large amount of Free Fatty Acids. Hence a two-step catalyzed process was followed to extract biodiesel from Waste cooking oil with high acid value. The Free Fatty Acids of Waste Cooking Oil were esterified with methanol catalyzed by ferric sulfate followed by transesterification with potassium hydroxide and methanol in the second step [20].