Duction of nitroblue tetrazolium (NBT) [35]. The reaction mixture consisted of 0.3 mL of phosphate buffer (0.05 M, pH = 7.8), 0.3 mL of methionine (130 mM), 0.3 mL of NBT (0.75 mM), 0.3 mL of edetate disodium (0.1 mM),0.three mL of riboflavin (0.02 mM), and 1.5 mL of enzymatic extract. The reaction mixture was incubated under visible light circumstances for 20 min at space temperature. The absorbance was measured at 560 nm making use of a UV is 5-BDBD Antagonist spectrophotometer. One unit of SOD activity (U) was defined as the quantity of enzyme essential to inhibit the photochemical reduction of NBT by 50 . 2.7. Statistical Analysis All statistical analyses had been carried out using SPSS 17.0 (SPSS Inc., Chicago, IL, USA). The information are expressed because the imply values with typical deviation values (mean SD) of triplicate treatment options. Information have been analyzed utilizing one-way evaluation of variance (ANOVA) and variations have been thought of statistically important at p 0.05. three. Outcomes and Discussion three.1. Growth Characteristics and Lipid Accumulation of Microalgae beneath Distinctive Nanoparticle Concentrations The biomass of Chlorella sp. UJ-3 CCP peptide Protocol increased together with the addition of Fe3 O4 NPs within a certain concentration range, but additional increases in the concentration of Fe3 O4 NPs resulted within a reduce in biomass (Figure 2). P rovet al. also discovered comparable trends in experiments on many microalgae with zero-valent iron nanoparticles [4]. Higher concentrations of nanoparticles have already been shown to inhibit algal biomass development, in all probability because the addition of nanoparticles creates a shadowing impact that blocks photosynthetic electron transport and impacts photosynthesis, eventually affecting the growrth of algal cells [36,37]. The total lipid content of Chlorella sp. UJ-3 did not modify significantly at low concentrations of Fe3 O4 NPs, although at high concentrations of Fe3 O4 NPs the total lipid content elevated drastically (Figure 2). Though the biomass of algal cultures decreased at higher concentrations of Fe3 O4 NPs, the total lipid production elevated as a consequence of the raise in total lipid content. Nonetheless, the total lipid production was lower at 200 mg/L of Fe3 O4 NPs due to the sharp reduce in algal biomass. The composition and content material of fatty acids are shown in Table S2. It was discovered that Chlorella sp. UJ-3 has a selection of fatty acids, in which the saturated (C16:0 and C18:0), monounsaturated (C16:1 and C18:1), and polyunsaturated (C18:2, C18:3, C20:5) fatty acids will be the important fatty acids in Chlorella sp. UJ-3. The results showed that the composition and content material of fatty acids have been pretty much unchanged when algal cells were exposed to low concentrations of Fe3 O4 NPs. Nevertheless, the polyunsaturated fatty acids (PUFA) content of Chlorella sp. UJ-3 increased when greater concentrations of Fe3 O4 NPs have been applied (Figure three).Nanomaterials 2021, 11, 2802 Nanomaterials 2021, 11, x FOR PEER REVIEW6 of 16 6 ofFigure 2. Biomass, total lipid contents, and lipid production of Chlorella sp. UJ-3 exp Figure 2. Biomass, Figure two. Biomass, totallipid 4contents, and lipid production of Chlorella days; Different numerous concentrationstotalFe3Ocontents, and lipid production of Chlorella sp. UJ-3 exposed to different on th of lipid nanoparticles (Culture time: 21 sp. UJ-3 exposed to letters concentrations of Fe3O4 nanoparticles (Culture time: 21 days; Distinct letters on the leading of column concentrations of Fe3 O4 variations involving 21 days; a, b, c, letters on the best of column indicate significantnanopartic.