Ginger (Zingiber officinale) extract mediated green synthesis of silver nanoparticles and evaluation of their antioxidant activity and potential catalytic reduction activities with Direct Blue 15 or Direct Orange 26.

The green synthesis of silver nanoparticles (AgNPs) using a water extract of Ginger (Zingiber officinale) root by microwave irradiation and its antibacterial activities have been reported. However, AgNPs prepared from different parts of ginger root water or ethanol extract by ultrasound synthesis and their antioxidant activity and whether the biogenic could be used to catalyze the reduction of hazardous dye are unknown. This study concentrated on the facile green synthesis of AgNPs prepared from different parts (unpeeled ginger, peeled ginger, and ginger peel) of ginger root water or ethanol extract by the ultrasound-assisted method. We studied their antioxidant activity and catalytic degradation of hazardous dye Direct Orange 26 (DO26) and Direct Blue 15 (DB15). The surface plasmon resonance (SPR) peak of AgNPs was at 428-443 nm. The biogenic AgNPs were approximately 2 nm in size with a regular spherical shape identified from TEM analysis. The ethanol extracts of dried unpeeled ginger and peeled ginger, fresh peeled ginger and ginger peel. The Z. officinale AgNPs synthesized by dried unpeeled ginger ethanol extract showed the best antioxidant activity. Their scavenging activities were significantly better than BHT (p <0.05). The different parts of ginger extracts showed no catalytic degradation activities of DB15 and DO26. Still, the synthesized Z. officinale AgNPs exhibited good catalytic degradation activities, while their ability to catalytic degradation to DB15 was better than DO26. In the additive ratio of 3 mL DB15, 0.1 mL NaBH4 and 0.1 mL AgNPs, the degradation rates of DB15 (or DO26) at 15 min, 30 min and 60 min were only 1.8% (0.9%), 2.8% (1.4%) and 3.5% (1.6%) in the absence of AgNPs. When adding Z. officinale AgNPs prepared from dried ginger peel ethanol extract or fresh ginger peel water extract, the degradation rates of DB15 sharply increased to 97% and 93% after 30 min, respectively. In conclusion, ginger extract has good antioxidant properties. Z. officinale AgNPs biosynthesis from ginger extract exhibit excellent catalytic degradation activities, especially for the ginger peel extract. They have application value in the treatment of textile effluents and provide a new idea and method for the comprehensive development and utilization of ginger resources.

Resveratrol inhibits lipid and protein co-oxidation in sodium caseinate-walnut oil emulsions by reinforcing oil-water interface.

Lipid-protein co-oxidation often causes nutrition loss, texture changes, and shortened shelf-life of emulsions. In this study, resveratrol significantly prevented lipid-protein co-oxidation in sodium caseinate (NaCas)-walnut oil emulsions, and the underlying mechanisms were explored in physical and chemical aspects. NaCas-walnut oil emulsions stabilized by resveratrol exhibited excellent physical stability at 55 °C for 12 days or at room temperature for 10 months due to forming a stable interfacial layer composed of resveratrol-modified NaCas. Furthermore, resveratrol binding caused NaCas structure's partial unfolding and a âˆ¼ 8% increase in hydrophobicity, in turn enhancing NaCas' emulsification properties and electrostatic repulsion. Besides, more than 90% of resveratrol was loaded at the interface and enhanced NaCas' Fe2+ chelating, DPPH scavenging abilities, and O2 quenching by âˆ¼ 22.6%, 5.26 times, and 31.84%, respectively. Simultaneously, resveratrol significantly improved NaCas' oxidative stability, as reflected by the decrease in adsorbed NaCas' intrinsic fluorescence loss and protein carbonyls gain by âˆ¼ 30% and 37%, respectively. Simultaneously, lipid hydroperoxides and TBARS were reduced by âˆ¼ 30% and 20% in the NaCas-walnut oil emulsions containing 6 mM resveratrol than the control. Our findings contribute to further understanding of the possible interaction among lipid, protein, polyphenols, and their oxidative products at the oil-water interface, minimizing lipid-protein co-oxidation and extending functional oils' shelf life. Finally, walnut oil emulsions with high physical and oxidative stabilities using resveratrol were prepared, further broadening resveratrol's application in the food industry.

Cyanidin-3-glucoside from Black Rice Ameliorates Diabetic Nephropathy via Reducing Blood Glucose, Suppressing Oxidative Stress and Inflammation, and Regulating Transforming Growth Factor ß1/Smad Expression.

Diabetic nephropathy (DN) is one of the serious complications in diabetes. Cyanidin-3-glucoside (C3G) from black rice was reported to have hypoglycemic effects and an anti-osteoporosis effect in diabetic rats. Whether it has preventive effects on DN has not been reported. In this study, we established a rat model of DN, and C3G at two doses (10 and 20 mg kg-1 day-1) were administered to see its anti-DN effect. A total of 8 weeks of C3G supplementation decreased blood glucose and serum insulin, improved the renal function, and relieved renal glomerular sclerosis and interstitial fibrosis of DN rats. Also, the kidneys of DN rats had improved the oxidative defense system. Pro-inflammatory mediators were markedly reduced in serum and kidneys of the C3G-treated groups. Transforming growth factor ß1 (TGF-ß1), phosphor-Smad2, and phosphor-Smad3 protein expression levels were significantly decreased in the kidney of the C3G-treated group, whereas the Smad7 expression level was upregulated by C3G. Our results indicate that C3G can ameliorate DN via antioxidative stress and anti-inflammation and regulate the TGF-ß1/Smad2/3 pathway. Our results suggest that C3G from black rice might be used as a renal-protective nutrient in DN.

Anthocyanin-rich extract from black rice (Oryza sativa L. Japonica) ameliorates diabetic osteoporosis in rats.

Diabetic osteoporosis (DOP) is a systemic endocrine-metabolic osteopathy which has the characteristics of bone mineral density (BMD) reduction and bone microstructural destruction. Although anthocyanin-rich extract from black rice (AEBR) was reported to have a beneficial effect on diabetic rats, no studies have been performed on whether black rice anthocyanins are beneficial for diabetic osteoporosis. Therefore, in this study, a streptozotocin-induced diabetic rat model was established to investigate the protective effect of AEBR on diabetes-induced osteoporosis and its possible mechanism. AEBR at three doses (0.5, 1.0, and 2.0 g kg-1 d-1) were administered by oral gavage to diabetic rats for 8 weeks. The blood glucose, BMD, bone histomorphometry parameters, serum bone turnover biomarkers, bone marrow adipocyte numbers, as well as osteoprotegerin (OPG), runt-related transcription factor 2 (RUNX 2), and receptor activator of nuclear factor-κ B ligand (RANKL) protein expression in bone and serum were detected. The results indicated that AEBR dose-dependently decreased the blood glucose, increased the BMD, and decreased the serum bone turnover markers. The bone microstructure and osteoclast numbers in bone tissues returned to normal in the high AEBR dosage group; at the same time, the AEBR dose-dependently suppressed bone marrow adipogenesis. The RUNX 2 as well as the OPG/RANKL ratio in diabetic rats' bone tissues increased significantly in the AEBR treatment group. Our results indicate that AEBR administration can ameliorate bone loss caused by diabetes; this is mainly attributed to its inhibition of bone turnover, suppression of bone marrow adipogenesis, and up-regulation of RUNX 2 and the OPG/RANKL expression ratio.

Elevated ß-Carotene Synthesis by the Engineered Rhodobacter sphaeroides with Enhanced CrtY Expression.

ß-Carotene is a precursor of vitamin A and a dietary supplement for its antioxidant property. Producing ß-carotene by microbial fermentation has attracted much attention owing to consumers' preference for the natural product. In this study, an engineered photosynthetic Rhodobacter sphaeroides producing ß-carotene was constructed by the following strategies: (1) five promoters of different strengths were used to investigate the effect of the expression level of crtY on ß-carotene content. It was found that PrrnB increased the ß-carotene content by 109%. (2) blocking of the branched pentose phosphate pathway by zwf deletion, and (3) overexpressing dxs could restore the transcriptional levels of crtE and crtB. Finally, the engineered RS-C3 has the highest ß-carotene content of 14.93 mg/g dry cell weight (DCW) among all of the reported photosynthetic bacteria and the ß-carotene content reached 3.34 mg/g DCW under light conditions. Our results will be available for industrial use to supply a large quantity of natural ß-carotene.

Anti-inflammatory effect of spilanthol from Spilanthes acmella on murine macrophage by down-regulating LPS-induced inflammatory mediators.

Spilanthes acmella (Paracress), a common spice, has been administered as a traditional folk medicine for years to cure toothaches, stammering, and stomatitis. Previous studies have demonstrated its diuretic, antibacterial, and anti-inflammatory activities. However, the active compounds contributing to the anti-inflammatory effect have seldom been addressed. This study isolates the active compound, spilanthol, by a bioactivity-guided approach and indicates significant anti-inflammatory activity on lipopolysaccharide-activated murine macrophage model, RAW 264.7. The anti-inflammatory mechanism of paracress is also investigated. Extracts of S. acmella are obtained by extraction with 85% ethanol, followed by liquid partition against hexane, chloroform, ethyl acetate, and butanol. The ethyl acetate extract exhibits a stronger free radical scavenging capacity than other fractions do, as determined by DPPH and ABTS radical scavenging assays. The chloroform extract significantly inhibits nitric oxide production ( p < 0.01) and is selected for further fractionation to yield the active compound, spilanthol. The diminished levels of LPS-induced inducible nitric oxide synthase (iNOS) and cyclooxygenase (COX-2) mRNA and protein expression support the postulation that spilanthol inhibits proinflammatory mediator production at the transcriptional and translational levels. Additionally, the LPS-stimulated IL-1beta, IL-6, and TNF-alpha productions are dose-dependently reduced by spilanthol. The LPS-induced phosphorylation of cytoplasmic inhibitor-kappaB and the nuclear NF-kappaB DNA binding activity are both restrained by spilanthol. Results of this study suggest that spilanthol, isolated from S. acmella, attenuates the LPS-induced inflammatory responses in murine RAW 264.7 macrophages partly due to the inactivation of NF-kappaB, which negatively regulates the production of proinflammatory mediators.