10-hydroxy-2-decenoic acid of royal jelly exhibits bactericide and anti-inflammatory activity in human colon cancer cells.

BACKGROUND: Royal jelly (RJ), the exclusive food for the larva of queen honeybee, is regarded as the novel supplement to promote human health. The function of RJ may be attributed to its major and unique fatty acid, 10-hydroxy-2-decenoic acid (10-HDA). The current study investigated the anti-inflammory function of 10-HDA on human colon cancer cells, WiDr, as well as its effect on the growth of pathogenic bacterium. METHODS: The pro-inflammatory cytokines, receptor antagonist cytokine (IL-1ra) and nuclear factor-kappa B (NF-κB) in WiDr cells was analyzed by Enzyme-linked immunosorbent assay (ELISA) or western blot. The growth inhibition of 10-HDA on bacterium was evaluated by determination of minimal inhibitory concentrations (MIC) and minimal bactericide concentrations (MBC). RESULTS: The production of pro-inflammatory cytokines, Interleukin (IL)-8, IL-1ß and tumor necrosis factor-alpha (TNF-α) in WiDr cells was modulated by 10-HDA. IL-8 were dramatically declined by 10-HDA at 3 mM, while IL-1ß and TNF-α were significantly decreased. 10-HDA increased IL-1ra in a dose manner. NF-κB pathway is primarily in response to prototypical pro-inflammatory cytokines, and NF-κB was reduced after 10-HDA treatment. 10-HDA acted as potent bactericide against animal- or human-specific pathogens, including Staphylococcus aureus, Streptococcus alactolyticus, Staphylococcus intermedius B, Staphylococcus xylosus, Salmonella cholearasuis, Vibro parahaemolyticus and Escherichia coli (hemolytic). CONCLUSIONS: The current study showed that in vitro 10-HDA from RJ exhibited anti-inflammatory activity in WiDr cells, as well as anti-bacterial activity against animal pathogens. 10-HDA showed its potential as anti-imflammtory agent and bactericide to benefit human gastrointestinal tract.

The functional property of royal jelly 10-hydroxy-2-decenoic acid as a melanogenesis inhibitor.

BACKGROUND: It has been reported that royal jelly would reduce melanin synthesis and inhibit the expression of melanogensis related proteins and genes. In this study, we evaluate the anti-melanogenic and depigmenting activity of 10-hydroxy-2-decenoic acid (10-HDA) from royal jelly of Apis mellifera. METHODS: In this study, we assesses the 10-HDA whitening activity in comparison with the changes in the intracellular tyrosinase activity, melanin content and melanin production related protein levles in B16F1 melanoma cells after treating with 10-HDA. Furthermore, the skin whitening effect was evaluated by applying a cream product containing with 0.5%, 1% and 2% of 10-HDA onto the skin of mice (C57BL/6 J) for 3 week to observe the effect of DL*-values. RESULTS: The results showed that 10-HDA inhibited the MITF protein expression (IC50 0.86 mM) in B16F1 melanoma cells. Western blot analysis revealed that 10-HDA inhibited the activity of tyrosinase and the expression of tyrosinase-related protein 1 (TRP-1), TRP-2, and microphthalmia-associated transcription factor (MITF) in B16F1 melanoma cells. In addition, the 10-HDA was applied on the skin of mice show significantly increased the average skin-whitening index (L value). CONCLUSIONS: The validation data indicated the potential of 10-HDA for use in suppressing skin pigmentation. The 10-HDA is proposed as a candidate to inhibit melanogenesis, thus it could be developed as cosmetics skin care products.

A unique caleosin serving as the major integral protein in oil bodies isolated from Chlorella sp. cells cultured with limited nitrogen.

Accumulation of oil bodies was successfully induced in a microalga, Chlorella sp., cultured in a nitrogen-limited medium. The oil bodies were initially assembled as many small entities (mostly 0.1-1 µm), and lately found as a major irregular compartment (>3 µm) occupying more than half of the cell space. Approximately, two thirds of oil bodies isolated from Chlorella cells were broken and formed a transparent oil layer on top of the milky compact layer of the remaining stable oil bodies after being washed with 0.1% triton X-100. The stable oil bodies mainly comprised triacylglycerols as examined by thin layer chromatography analysis and confirmed by both Nile red and BODIPY stainings. Integrity of these stable oil bodies was maintained via electronegative repulsion and steric hindrance possibly provided by their surface proteins. Immunological cross-recognition revealed that a major protein of 29 kDa, tentatively identified as caleosin, was exclusively present in Chlorella oil bodies. Mass spectrometric analysis showed that the putative caleosin possessed a trypic fragment of 13 residues matching to that of a hypothetical caleosin in Picea sitchensis. With the aid of a degenerate primer designed according to the tryptic peptide, a complete cDNA fragment encoding this putative caleosin was obtained by PCR. Phylogenetic tree analysis supports that Chlorella caleosin is the most primitive caleosin found in oil bodies to date.

Size and stability of reconstituted sesame oil bodies.

Oil bodies of sesame seeds comprise a triacylglycerol matrix, which is surrounded by a monolayer of phospholipids embedded with unique proteins, mainly structural proteins termed oleosins. Artificial oil bodies were successfully reconstituted with various compositions of triacylglycerols, phospholipids, and oil-body proteins. The sizes of reconstituted oil bodies displayed a normal distribution with an average size proportional to the ratio of triacylglycerols to oil-body proteins. Both thermostability and structural stability of reconstituted oil bodies decreased as their sizes increased, and vice versa. Proteinase K digestion indicated that oleosins anchored both native and reconstituted oil bodies via their central hydrophobic domains. The stability of reconstituted oil bodies, as well as the purified ones from sesame seeds, could be substantially enhanced after their surface proteins were cross-linked by glutaraldehyde or genipin.