Elaboration and characterization of curcumin-loaded soy soluble polysaccharide (SSPS)-based nanocarriers mediated by antimicrobial peptide nisin.

Curcumin was recently attracted great interest owing to its multiple bioactivities; however, the use of curcumin was hindered by its poor solubility and stability. In this study, curcumin-nisin-soy soluble polysaccharide nanoparticles (Cur-Nisin-SSPS-NPs, size = 118.76 nm) have been successfully elaborated to improve the application of curcumin. The formation of Cur-Nisin-SSPS-NPs was mediated by amphiphilic and positively charged nisin: SSPS encapsulated nisin, which was mainly driven by electrostatic attraction. And nisin-SSPS complex encapsulated curcumin mainly through hydrophobic interactions between nisin and curcumin. The encapsulation efficiency of curcumin (91.66%) in this novel nanocarriers was significantly higher than that in nanoparticles prepared by a single SSPS (31.82%) or nisin (41.69%), most likely because more hydrophobic regions of nisin were exposed after interacting with SSPS through electrostatic interaction. Consequently, this facile and green nanocarriers improved the solubility/dispersibility and stability of curcumin and nisin, as well as endowed SSPS-based nanoparticles with antioxidant and antimicrobial activities.

Effect of antioxidant compounds from seaweeds on storage stability of C20-22 polyunsaturated fatty acid concentrate prepared from dogfish liver oil.

Ethyl acetate extracts of seaweeds were chromatographically fractionated to yield 14-methyl pentyl tetrahydro-8-hydroxy-10-methylnaphthalene-8-carboxylate (1) and tetrahydro-4-isopropyl-9-(9, 14-dimethyldec-9-enyl)-pyran-1-one (2) from Sargassum ilicifolium, whereas Padina gymnospora afforded dihydro-2-(10-(hydroxymethyl)-7,15-dimethyl-9-oxoundec-11-enyl)-2-methyl-2H-pyran-1(4H)-one (3) and 1-(decahydro-1-hydroxy-7-methyl-8-vinylnaphthalen-2-yl)ethanone (4) as major constituents. Compound 1 displayed significantly higher antioxidant activity (IC50 < 1 mg/mL, p < 0.05) comparable to other analogues (IC50 > 1 mg/mL). The C20-22 polyunsaturated fatty acid (C20-22 PUFA) concentrate (CFA) prepared from the deep-sea dogfish liver oil was added with the studied compounds and physiochemical properties and fatty acid composition during an accelerated storage were evaluated. No significant reduction in C20-22 PUFAs (∼6%) in the CFA treated with 1 as compared to that with the control (∼35%) was recorded. A greater induction time was observed for the CFA supplemented with 1 (6.8 h) than other compounds (≤6 h) and control (∼1.6 h), maintaining the oxidation indices of the CFA within desirable limits.

Spectroscopic studies on the antioxidant activity of p-coumaric acid.

p-coumaric acid (4-hydroxycinnamic acid), a phenolic acid, is a hydroxyl derivative of cinnamic acid. It decreases low density lipoprotein (LDL) peroxidation and reduces the risk of stomach cancer. In vitro radical scavenging and antioxidant capacity of p-coumaric acid were clarified using different analytical methodologies such as total antioxidant activity determination by ferric thiocyanate, hydrogen peroxide scavenging, 1,1-diphenyl-2-picryl-hydrazyl free radical (DPPH) scavenging, 2,2'-azino-bis(3-ethylbenzthiazoline-6-sulphonic acid) (ABTS) radical scavenging activity and superoxide anion radical scavenging, ferrous ions (Fe(2+)) chelating activity and ferric ions (Fe(3+)) reducing ability. p-Coumaric acid inhibited 71.2% lipid peroxidation of a linoleic acid emulsion at 45µg/mL concentration. On the other hand, butylated hydroxyanisole (BHA), butylated hydroxytoluene (BHT), α-tocopherol and ascorbic acid displayed 66.8%, 69.8%, 64.5% and 59.7% inhibition on the peroxidation of linoleic acid emulsion at the same concentration, respectively. In addition, p-coumaric acid had an effective DPPH scavenging, ABTS(+) scavenging, superoxide anion radical scavenging, hydrogen peroxide scavenging, ferric ions (Fe(3+)) reducing power and ferrous ions (Fe(2+)) chelating activities. Also, those various antioxidant activities were compared to BHA, BHT, α-tocopherol and ascorbic acid as references antioxidant compounds. These results suggested that p-coumaric acid can be used in the pharmacological and food industry because of these properties.