Recovery of γ-Oryzanol from Rice Bran Acid Oil by an Acid-base Extraction Method with the Assistance of Response Surface Methodology.

A rapid and low energy consumption method for the recovery of γ-oryzanol from rice bran acid oil (RBAO), a byproduct of rice bran oil (RBO) refining, is presented. The RBAO was converted to the fatty acid ethyl ester (FAEE) and was used as the starting material. The dissolved γ-oryzanol was separated from the FAEE using an acid-base extraction method with alkaline aqueous ethanol and hexane as extraction media. A systematic investigation of the extraction yield was carried out by applying response surface methodology (RSM) based on central composite design (CCD) and Derringer's desirability function. The concentration of NaOH, the percentage of ethanol in water, the hexane content and their interactions showed significant effects on the yield of γ-oryzanol and FAEE. The optimal extraction conditions were as follows: extraction time of 1 min at room temperature (28-32°C); extraction medium: 1.855 M NaOH; 75.91% ethanol in water and 20.59% hexane in the total volume of the extractant; and FAEE to extractant ratio of 1:10 corresponding to a maximum γ-oryzanol yield of 75.82±3.44% and the desired FAEE yield of 54.42±7.80%. The γ-oryzanol-rich fraction was further purified by washing with a 2% Na2CO3 solution, obtaining 69.94% recovery yield with 89.90% purity of γ-oryzanol. The purified γ-oryzanol showed good scavenging activity on the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical and the ABTS radical and was comparable to the commercial product, clearly suggesting that the presented process was efficient and feasible.

Identification of ß-Sitosterol as in Vitro Anti-Inflammatory Constituent in Moringa oleifera.

ß-Sitosterol is a well known phytosterol in plants, but owing to its poor solubility in typical media, determining its cellular mechanisms has been proven to be difficult. In this study, we investigated the anti-inflammatory activity of ß-sitosterol (BSS) isolated from Moringa oleifera in two cell lines. Over a dose range of 7.5 to 30 µM, BSS dispersed well in the medium as nanoparticles with diameters of 50 ± 5 nm and suppressed the secretion of inflammatory factors from keratinocytes and macrophages induced by PGN, TNF-α, or LPS, such as TNF-α, IL-1ß, IL-6, IL-8, and ROS, separately. In addition, BSS significantly reduced the expression of NLRP3, a key component of NLRP3 inflammasomes, and inhibited the activation of caspase-1. There was partial inhibition of NF-κB in macrophages. This is the first study to report an increase in the solubility of nearly water-insoluble phytosterols via the formation of nanoparticles and to delineate the formulation's capacity to inhibit the signal transduction pathways of inflammation in macrophages.

Separation of Vitamin E on a 100-Å Phenogel Column.

The effect of π-electrons and hydroxyl group on the separations of vitamin E on a swelling-controlled polystyrene-divinylbenzene (Phenogel) column using toluene/isooctane as the mobile phase was investigated. The effect of the π-electrons was demonstrated in the baseline separation of α-tocopherol and α-tocotrienol on a 100-Å Phenogel column. In addition, baseline separation of α-, (ß- + Î³-)- and δ-tocopherol could be achieved on this column. The separation mechanism of these isomers are due to the difference in the interactions between the hydroxyl group on the chromanol ring of each tocopherol and the gel matrix caused by the steric hindrance of methyl group(s). It was concluded that solutes of the same molecular size but different in the polar groups could be separated on a high performance size-exclusion chromatography by controlling the swelling of the gel matrix via modification of the mobile phase.

Composition and antifungal activities of the leaf essential oil of Litsea coreana from Taiwan.

The hydrodistilled leaf essential oil of Litsea coreana was analyzed by GC/FID and GC/MS. Fifty-two compounds were identified, the main components being n-decanal (27.5%), 2E,6E-farnesol (25.8%), beta-eudesmol (10.3%), ethyl n-dodecanoate (8.0%) and tau-cadinol (6.6%). Oxygenated sesquiterpenes (56.8%) and non-terpenoids (37.0%) were the predominant groups of compounds. The leaf oil exhibited excellent antifungal and anti-wood-decay fungal activities.

Osthole regulates inflammatory mediator expression through modulating NF-κB, mitogen-activated protein kinases, protein kinase C, and reactive oxygen species.

Osthole, a coumarin compound, has been reported to exhibit various biological activities; however the cellular mechanism of its immune modulating activity has not yet been fully addressed. In this study we isolated osthole from the seeds of Cnidium monnieri and demonstrated that osthole inhibited TNF-α, NO and COX-2 expression in LPS-stimulated macrophages, without reducing the expression of IL-6. Furthermore, the phosphorylation of p38, JNK1/2, PKC-α and PKC-ε induced by LPS was inhibited by osthole; however, the phosphorylation of ERK1/2 and PKC-δ was not reduced by osthole. Osthole also inhibited NF-κB activation and ROS release in LPS-stimulated macrophages. Our current results indicated that osthole is the major anti-inflammatory ingredient of Cnidium monnieri seed ethanol extract.

Immunostimulatory bioactivity of algal polysaccharides from Chlorella pyrenoidosa activates macrophages via Toll-like receptor 4.

Much research suggests that a dietary supplement of Chlorella pyrenoidosa may be helpful to human health, but the molecular mechanism involved remains unclear. The aim of this research was to investigate the effects of certain hot-water-soluble polysaccharides from Chlorella pyrenoidosa (CWSP) on cytokine production, human leukocyte antigen (HLA) expression, and costimulatory molecule expression in macrophages. We demonstrated that CWSP induced IL-1beta secretion in macrophages via Toll-like receptor 4 (TLR4) mediated protein kinase signaling pathways. In addition, CWSP also stimulated the cell surface expression of HLA-DA, -DB, and -DC, and HLA-DR, -DP, and -DQ as well as the expression of costimulatory family molecules such as CD80 and CD86 in macrophages. Furthermore, we demonstrated that preinjection of C57BL/6J mice with CWSP increased lipopolysaccharide (LPS)-induced tumor necrosis factor-alpha and IL-1beta secretion into serum in vivo. This outcome was consistent with the corresponding outcome for cells treated with CWSP in vitro. Our current results provide support for the possible use of CWSP as a modulation agent of immune responses in humans and certain animal species. Finally, in using GC-MS to analyze the polysaccharides, we found that the major monosaccharides of CWSP were rhamnose (31.8%), glucose (20.42%), galactose (10.28%), mannose (5.23%), and xylose (1.27%). This study is the first to report the molecular mechanism of immune-modulated signal transduction in vitro from the polysaccharides of Chlorella pyrenoidosa.