Inhibitory effect of Aucubin isolated from Eucommia ulmoides against UVB-induced matrix metalloproteinase-1 production in human skin fibroblasts.

Of 30 herbal plants tested, the methanol extracts of Eucommia ulmoides (52%), Evodia officinalis (45%), and Pleuropterus multiflorus (41%) each showed a potent inhibitory effect on the matrix metalloproteinase-1 (MMP-1) production in ultraviolet B (UVB)-irradiated human fibroblasts. Aucubin was isolated as the MMP-1 inhibitor from E. ulmoides, and significantly suppressed the production of MMP-1 by nearly 57% compared to the control. It also reduced MMP-1 mRNA expression. These results suggest that aucubin is a photoprotective phytochemical, and could be used as a potential agent in preventing photoaging.

Protective effects of aucubin isolated from Eucommia ulmoides against UVB-induced oxidative stress in human skin fibroblasts.

Ultraviolet-B (UVB) irradiation has been demonstrated to produce reactive oxygen species (ROS) in the cells and skin, which induces the synthesis of matrix metalloproteinases (MMPs), causing skin photoaging. Using the human skin fibroblast HS68 cell line in the present study, we investigated the photoprotective effects of aucubin from Eucommia ulmoides. Pretreatment with aucubin significantly inhibited the production of MMP-1 by 57% when compared to the UVB-irradiated cells. Additionally, the senescence-associated beta-galactosidase (SA beta-gal) activity was markedly decreased in the presence of aucubin, which indicates it as an antiphoto-induced aging compound. As the effect of aucubin was determined against ROS, the inhibited ROS formation and malondialdehyde (MDA) levels, and the increased cell viability and glutathione (GSH) level were observed with aucubin under UVB irradiation. Based upon these results, it was suggested that aucubin might play an important role in the cellular defense mechanism against UV radiation-induced photoaging. An understanding of the antioxidant properties of aucubin could, in part, act to elucidate its protective mechanism on the human skin photoaging.

Effect of culture conditions on production of 5-aminolevulinic acid by recombinant Escherichia coli.

Aminolevulinic acid (ALA) is formed by the enzyme ALA synthase (hemA gene). Then ALA is converted to Porphobilinogen (PBG) by the ALA dehydratase (hemB gene). For the overproduction of ALA, we used an Escherichia coli BL21(DE3) containing a hemA gene from Bradyrhzobium japonicum, which was created in our previous work. The effects of pH on the ALA synthase and ALA dehydratase were investigated. The ALA synthase and ALA dehydratase activities were dependent on the pH of the medium, with maximal activities occurring at pH 6.5 and 8.0 respectively. At pH 6.5, extracellular ALA reached 23 mM in a jar-fermenter. In addition, the effects of some nutritional factors, such as nitrogen source and the ratio of carbon to nitrogen (C/N) on the fermentative production of ALA were investigated. The highest ALA production was found with 8:1 of C/N ratio. Among various nitrogen sources, the tryptone might be a useful one for ALA production.

Biochemical properties of polysaccharides from black pepper.

The purified polysaccharides from Piper nigrum were prepared as follows: a hot water extract of pepper seeds was fractionated by ultrafiltration with a 5-kDa-membrane cartridge. A fraction with 5 kDa or bigger molecules was successively purified by open column chromatography on DEAE-Toyopearl 650C and Bio-gel P-60 with each active fraction, resulting in PN-Ib and PN-IIa, purified anti-complementary polysaccharides. None of the anti-complementary activity of any polysaccharide was changed by pronase digestion or polymyxin B treatment, but they were decreased by periodate oxidation. Analysis of component sugar and molecular mass determination of the anti-complementary polysaccharides indicated that PN-Ib with an average molecular mass of 21 kDa contained 88.5% glucose and other negligible minor monosaccharides, while PN-IIa showed a different monosaccharide composition, which contained a significant proportion of galactose, arabinose, galacturonic acid and rhamnose. The molar ratio of galactose and arabinose of PN-IIa (48 kDa) was 1.93:1. PN-1 did not react with beta-glucosyl Yariv reagent, however, PN-IIa did react, which indicated that PN-IIa might be an arabinogalactan. Based upon these results, the usefulness of purified anti-complementary polysaccharides from Piper nigrum is suggested as a supplement for immune enhancement.

Gene cloning and biochemical analysis of thermostable chitosanase (TCH-2) from Bacillus coagulans CK108.

The DNA sequence of the thermostable chitosanase TCH-2 gene from Bacillus coagulans CK108 showed a 843-bp open reading frame that encodes a protein of 280 amino acids with a signal peptide corresponding to 32 kDa in size. The deduced amino acid sequence of the chitosanase from Bacillus coagulans CK108 has 61.6%, 48.0%, and 12.6% identities to those from Bacillus ehemensis, Bacillus circulans, and Bacillus subtilis, respectively. C-Terminal homology analysis shows that the enzyme belongs to the Cluster I group. The size of the gene was similar to those from mesophiles of the Cluster I group with regard to higher preference for codons ending in G or C. The recombinant chitosanase was electrophoretically purified to homogeneity by only two steps with column chromatography. The half-life of the enzyme was 40 min at 90 degrees C. The purified protein was also highly stable, retaining above 50% residual activities during treatment with denaturants such as urea (8 M) and guanidine x HCl (4 M) at 37 degrees C for 30 min. The enzyme had a useful reactivity and a high specific activity for producing functional oligosaccharides as well, producing the tetramer as a major product.

In vitro and in vivo effects of macrophage-stimulatory polysaccharide from leaves of Perilla frutescens var. crispa.

The crude polysaccharide (PFB-1) was isolated from the leaves of Perilla frutescens var. crispa by the sequential procedures with hot-water extraction, methanol reflux, and ethanol precipitation. It was further purified by anion column chromatography in order to obtain the partially purified polysaccharide (PFB-1-0). In the presence of PFB-1-0, strong cellular lysosomal enzyme activity of murine peritoneal macrophages was observed in vitro. Compared to bacterial lipopolysaccharide (LPS), its activity was relatively high. The in vitro phagocytic activity was enhanced by PFB-1-0 as the similar pattern in both gram-negative bacteria, E. coli, and gram-positive bacteria, S. aureus with a time-dependent manner. We also investigated the production of several mediators by murine peritoneal macrophages upon stimulation with PFB-1 (in vivo) or PFB-1-0 (in vitro). The levels of nitric oxide (NO) and tumor necrosis factor (TNF)-alpha were increased in the presence of PFB-1-0 in vitro. The PFB-1 stimulated the production of interleukin (IL)-6 and granulocyte-macrophage colony-stimulating factor (GM-CSF) in vivo. Results suggest that the polysaccharide from P. frutescens var. crispa represents an immunopotentiator and biological response modifiers in vitro and in vivo levels.