Evaluating the hypolipidemic effect of garlic essential oil encapsulated in a novel double-layer delivery system.

The limited application of garlic essential oil (GEO) is attributed to its pungent taste, poor water solubility and low bioavailability. Liposomes are nontoxic, biodegradable and biocompatible, and ß-cyclodextrin can inhibit undesirable odors and improve the stability and bioavailability. Thus a promising dual-layer GEO ß-cyclodextrin inclusion compound liposome (GEO-DCL) delivery system with both advantages was designed and prepared in this study. Experimental results indicated that the encapsulation efficiency of GEO-DCLs was 5% higher than that of GEO liposomes (GEO-CLs), reaching more than 88%. In vitro release experiment showed that the release rate of GEO in GEO-DCLs was 40% lower than that of GEO-CLs after incubation in gastric juice for 6-h, indicating that the stability of GEO-DCLs was better than GEO-CLs. Evaluation of the effects of GEO-DCLs on lowering blood lipid levels in hypercholesterolemia mice. GEO-DCLs could reduce the weight and fat deposition in hypercholesterolemia mice. Inhibiting the increase of TC, LDL-C, and decrease of HDL-C in mice. The degree of liver injury was decreased, the number of round lipid droplets in liver cytoplasm was reduced, and the growth of fat cells was inhibited. The lipid-lowering effects of GEO-DCLs were dose-dependent. GEO-DCL can improve the bioavailability of GEO and improve dyslipidemia. Based on GEO's efficacy in lowering blood lipids, this study developed a kind of GEO-DCL compound pomegranate juice beverage with good taste, miscibility and double effect of reducing blood lipids. This study lays a foundation for the application of GEO in the field of functional food.

Improving the bioavailability and bioactivity of garlic bioactive compounds via nanotechnology.

This review highlights main bioactive compounds and important biological functions especially anticancer effects of the garlic. In addition, we review current literature on the stability and bioavailability of garlic components. Finally, this review aims to provide a potential strategy for using nanotechnology to increase the stability and solubility of garlic components, providing guidelines for the qualities of garlic products to improve their absorption and prevent their early degradation, and extend their circulation time in the body. The application of nanotechnology to improve the bioavailability and targeting of garlic compounds are expected to provide a theoretical basis for the functional components of garlic to treat human health. We review the improvement of bioavailability and bioactivity of garlic bioactive compounds via nanotechnology, which could promisingly overcome the limitations of conventional garlic products, and would be used to prevent and treat cancer and other diseases in the near future.

Enhancing stability and anti-inflammatory properties of curcumin in ulcerative colitis therapy using liposomes mediated colon-specific drug delivery system.

Curcumin liposomes (CUR-LPs) was identified by evaluating morphology, appearance, zeta potential, particle diameter, and drug encapsulation efficiency. The results indicated that particle diameter, surface charge and polydispersity index (PDI) of curcumin (CUR)-loaded anionic liposomes were 167 nm, -34 mV and 0.09, respectively. CUR-LPs is high stable pseudo-pH-sensitive nanoparticles system which has a favorable stability in simulated gastric fluid and slower degradation rate allowing CUR sustained release for prolonged times in simulated intestinal fluid. Within 1 h, the CUR consumption was 21.82% in simulated gastric fluid (SGF) and 27.32% in simulated intestinal fluid (SIF), respectively. CUR-LPs could attenuate clinical symptoms including weight loss, diarrhea and fecal bleeding. Especially, it could also prevent dextran sulfate sodium salt (DSS)-inducedcolon tissue damage and colon shortening, and reduce the production of malondialdehyde (MDA), colonic myeloperoxidase (MPO), Interleukin-6 (IL-6) and tumor necrosis factor-α (TNF-α) in animal model. Our study illustrated that liposomes (LPs) was a potential carrier to develop the colon-specific drug delivery system incorporating CUR for treating ulcerative colitis.

Effects and mechanism of free amino acids on browning in the processing of black garlic.

BACKGROUND: Black garlic is produced by heating raw garlic at a high temperature for a long time without any additives. The thermal processing induces many chemical reactions, such as the Maillard reaction, which causes the color change from white to dark brown. Garlic contains a variety of amino acids, and the effect of each amino acid on browning is not fully understood. This work investigated the effect and mechanism of free amino acids on the browning of black garlic using model solutions containing garlic neutral polysaccharide, hydrolyzed garlic neutral polysaccharide, fructose, and free amino acids. RESULTS: A significant increase in reducing sugar was detected when garlic neutral polysaccharide was heated with glycine. The browning intensity of garlic neutral polysaccharide-glycine model solution was obviously higher after heating at 80 °C compared with that of garlic neutral polysaccharide solution. The model solution containing histidine had the greatest browning degree. The histidine model has a stable pH value, and almost no 5-hydroxymethylfurfural (5-HMF) was detected. CONCLUSION: Amino acid can promote the breaking of the garlic neutral polysaccharide chain and can react with the fructose generated to form browning. Histidine has the greatest effect on the browning, because histidine could eliminate the inhibiting effect of organic acid on Maillard reaction due to the buffer ability, and histidine had high reactivity in the late stage of Maillard reaction. © 2019 Society of Chemical Industry.

In vitro antioxidant and anti-inflammatory activities of 1-dehydro-[6]-gingerdione, 6-shogaol, 6-dehydroshogaol and hexahydrocurcumin.

Hexahydrocurcumin, 1-dehydro-[6]-gingerdione, 6-dehydroshogaol and 6-shogaol were evaluated for their antioxidant and anti-inflammatory activities in the present study. The relative antioxidant potencies of ginger compounds decreased in similar order of 1-dehydro-[6]-gingerdione, hexahydrocurcumin>6-shogaol>6-dehydroshogaol in both 1,1-diphenyl-2-picyrlhydrazyl (DPPH) radical-scavenging and trolox equivalent antioxidant capacity (TEAC) assays. All tested compounds could attenuate lipopolysaccharide (LPS)-elicited increase of prostaglandin E2 (PGE(2)) in murine macrophages (RAW 264.7) in a concentration-dependent manner but hexahydrocurcumin of 7µM and 6-shogaol of 7µM. The strongest inhibitory effect was observed for 6-dehydroshogaol and 6-shogaol at 14µM with the inhibition of 53.3% and 48.9%, respectively. Furthermore, both 6-dehydroshogaol and 1-dehydro-[6]-gingerdione significantly suppressed the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2) proteins in a concentration-dependent fashion. These results contribute to our theoretical understanding of the potential beneficial effects of consuming ginger as a food and/or dietary supplement.

A new pyrrolidine derivative and steroids from an algicolous Gibberella zeae strain.

A new pyrrolidine derivative, 3-hydroxy-5-(hydroxymethyl)-4-(4'-hydroxyphenoxy)pyrrolidin-2-one (1), and eight known steroids, (22E,24R)-7beta,8beta-epoxy-3beta,5alpha,9alpha-trihydroxyergosta-22-en-6-one (2, a reassigned structure of (22E,24R)-5alpha,6alpha-epoxy-3beta,8beta,14alpha-trihydroxyergosta-22-en-7-one), (22E,24R)-3beta,5alpha,9alpha-trihydroxyergosta-7,22-dien-6-one (3), (22E,24R)-3beta,5alpha-dihydroxyergosta-7,22-dien-6-one (4), (22E,24R)-ergosta-7,22-dien-3beta/,5alpha,6beta-triol (5), (22E,24R)-ergosta-5,22-dien-3beta-ol (6), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,22-dien-3beta-ol (7), (22E,24R)-5alpha,8alpha-epidioxyergosta-6,9(11),22-trien-3beta-ol (8), and (22E,24R)-1(10 --> 6)-abeo-ergosta-5,7,9,22-tetraen-3alpha-ol (9), were isolated from the cultures of Gibberella zeae, an endophytic fungus isolated from the marine green alga Codium fragile. Their structures and relative stereochemistry were elucidated by 1D, 2D NMR and mass spectroscopic techniques. Compound 1 showed cytotoxicity against A-549 and BEL-7402 cell lines.