Effect of culture conditions on the physicochemical properties and antioxidant activities of polysaccharides from Nostoc flagelliforme

Extraction Optimization, Structural Characterization, and Antioxidant Activities of Polysaccharides from Cassia Seed (Cassia obtusifolia)

“…The presence of electrophilic groups such as keto or aldehyde in acidic polysaccharides could improve the radical scavenging activities [30]. In this study, the higher antioxidant activities (ABTS, DPPH, NO, and OH radical scavenging activities, and reducing power) observed in CSP-M might be partially attributed to its lower M w and higher content of unmethylated galacturonic acids [4,23]. However, further purification, structural characterization, and in vitro and in vivo antioxidant activities of CSPs are required to reveal their relationships between structure and bioactivity.…”

“…It is well known that some of these ROSs play positive roles in vivo [2]. However, an excessive amount of ROSs can damage cellular components such as lipids, proteins, and DNA when the innate defense in the human body is not enough for severe oxidative stress, a variety of diseases will happen including cancer, aging, and other diseases [3,4,5]. Generally, antioxidants play important roles in the protection of living organisms [6].…”

Marine Bacteria versus Microalgae: Who Is the Best for Biotechnological Production of Bioactive Compounds with Antioxidant Properties and Other Biological Applications?

“…Furthermore, some non-carbohydrate compounds with antioxidant properties, which are extracted alongside polysaccharides, are occasionally believed to be obstructions for the source of the detected scavenging activities [271]. The isolated antioxidant polysaccharides from prokaryotic microalgae such as Spirulina platensis and Nostoc flagelliforme and eukaryotic microalgae such as Navicula sp., Rhodella reticulata, Porphyridium sp., Porphyridium cruentum, Dunaliella salina, Schizochytrium sp., and Isochrysis galbana have effective scavenging activities on hydroxyl radicals, hydroxyl peroxide, and superoxide radicals [24,[273][274][275][276][277][278]. The absence of appropriately defined structures is an obstacle on the way of polysaccharide application in the fields of food and health, even though in many studies the scavenging abilities of these polysaccharides have been verified.…”

“…Likewise, three polysaccharides that have been isolated from Nostoc flagelliforme, cultivated in normal, salt stress, and mixotrophic conditions, contain nine different monosaccharides with their uronic acid content, monosaccharide ratio, and molecular weights differing on the basis of the conditions of their culture. The polysaccharides isolated from mixotrophic culture conditions exhibit the highest antioxidant activity, even though all these polysaccharides demonstrate robust scavenging activity on hydroxyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) radicals (ABTS•) [273]. The thing that makes it challenging to accomplish an accepted structural adaptation of EPS to environmental conditions is the lack of complete characterization of polysaccharides to detect real structural differences.…”

Biological activity of methanol extract from Nostoc sp. N42 and Fischerella sp. S29 isolated from aquatic and terrestrial ecosystems

“…Они играют важную роль в ингибировании и удалении радикалов, обеспечивая защиту людей от инфекций и дегенеративных заболеваний (Wu et al, 2010). Перспективной стратегией замены антибактериальных и противогрибковых химикатов является продви-жение продуктов естественного биологического контроля, полученных из микроводорослей (Shen et al, 2018). Так, штаммы цианобактерий предотвращают окисление, удаляя свободные радикалы и активный кислород и косвенно уменьшая образование раковых клеток в организме человека (Kamble et al, 2013).…”