海绵共附生菌Streptomyces olivaceus LHW2444的分离鉴定及其抗青枯菌活性代谢产物研究

目的 从海绵中分离培养放线菌,筛选具有抗青枯菌活性的菌株,分离鉴定活性代谢产物。方法 以来源于南海西沙永兴岛附近海域的海绵Leucetta chagosensis为实验材料,采用三种选择性分离培养基分离海绵的共附生放线菌,利用16S rRNA序列分析对各菌株进行种属鉴定。对各菌株的发酵提取物进行抗青枯菌活性筛选,采用硅胶柱层析、Sephadex LH-20凝胶柱层析和高效液相色谱法对筛选到的活性菌株的发酵产物进行分离、纯化,运用核磁共振(NMR)、质谱(MS)等手段,鉴定化合物的结构。采用微量稀释法测定化合物的最小抑菌浓度(MIC)。结果 分离培养海绵共附生放线菌16株,筛选得到一株具有较好抗青枯菌活性的菌株Streptomyces olivaceus LHW2444,并从该菌株的发酵产物中分离鉴定2个吡咯类化合物、1个苯并二恶茂类化合物、2个吡喃酮类化合物,分别为pyrrole-2-carboxamide(1)、pyrrole-2-carboxylic acid(2)、1,3-benzodioxole-2-one-4-carboxylamide(3)、germicidin B(4)、germicidin C(5),化合物1-5为首次从该种属放线菌分离得到。首次发现pyrrole-2-carboxylic acid对青枯菌具有较强抑制作用,MIC值为8 μg/mL。结论 海绵共附生菌Streptomyces olivaceus LHW2444是潜在的植物青枯病生防菌,pyrrole-2-carboxylic acid是抗青枯菌的活性代谢产物。     

不同鲨鱼皮胶原蛋白的分离及其特性研究

目的 探讨不同鲨鱼皮胶原蛋白的分离方法,并对分离胶原蛋白的部分生化特性进行研究.方法 用稀碱溶胀酶解法争缓冲液溶胀分离法分别从水鲨头皮和马鲛鲨皮中分离胶原蛋白,利用聚丙烯酰胺凝胶电泳法(SDS-PAGE)、差示扫描量热仪法(DSC)、园二色谱仪法(CD)对分离胶原蛋白进行纯度及分子大小、变性温度和二级结构的测定.结果 鲨鱼皮胶原蛋白回收率为鲜重的2.9%～4.1%;分离胶原蛋白在SDS-PAGE上呈现清晰的3条谱带,相对分子质量分别为205,134,118 KDa水鲨头皮和马鲛鲨皮胶原蛋白的热变性温度分别为69℃、47℃;两种分离胶原蛋白的二级结构均主要是β-折叠和无规卷曲,不存在α-螺旋.结论 采用稀碱溶胀酶解法和缓冲液溶胀分离法均能制备高纯度的胶原蛋白,从水鲨头皮和马鲛鲨皮分离的胶原蛋白相对分子质量争分子构成一致,但提取条件的不同能影响胶原蛋白的热变性温度和二级结构.     

L-amino acid oxidase from Vipera lebetina venom: isolation, characterization, effects on platelets and bacteria.

The L-amino acid oxidase from Vipera lebetina venom was purified to homogeneity using combination of size exclusion, ion exchange and hydrophobic chromatography. The monomeric molecular mass of the homodimeric enzyme is 60.9kDa. The N-terminal and the tryptic peptides share high homology with other snake venom L-amino acid oxidases. The enzyme displays high specificity towards hydrophobic L-amino acids, the best substrates are L-Met, L-Trp, L-Leu followed by L-His, L-Phe, L-Arg and L-Ile. Six substrates-Gly, L-Ser, L-Thr, L-Pro, L-Cys, L-Asp--were not oxidized. The enzyme has antimicrobial activity inhibiting the growth of both Gram-negative and Gram-positive bacteria. V. lebetina LAAO dose-dependently inhibited platelet aggregation induced by ADP or collagen. In case of ADP-induced aggregation the inhibitory effect was more pronounced on the second wave of aggregation.     

Extraction,optimization and characterization of collagen from sole fish skin

In this study, collagen was successfully extracted from marine waste i.e. Sole fish skin, which is available in the coastal area of Mangalore, India. The extraction process was optimized using One Variable at a Time (OVAT) and Response Surface Methodology (RSM) with Box-Behnken Design (BBD) was to achieve maximum yield and the extracted collagen was characterized. The optimal conditions to obtain highest collagen yield was determined to be, an acetic acid concentration of 0.54 M, NaCl concentration of 1.90 M, solvent/solid ratio of 8.97 ml/g and time of 32.32 h. The maximum collagen yield of 19.27 ± 0.05 mg/g of fish skin was achieved under the optimal conditions. The analysis of variance and contour plots exhibited a significant interaction of all the selected variables over collagen extraction process. The SDS-PAGE (Sodium dodecyl sulfate - polyacrylamide gel electrophoresis) analysis suggested that the extracted collagen contained three α-chains i.e. (α1)₂, α2 (M.W. 118, 116 kDa) and one β chain (M.W. 200 kDa) which was similar to commercially available calfskin Type I collagen. FT-IR (Fourier Transform Infrared Spectroscopy) analysis confirmed the existence of helical arrangements of collagen. SEM (Scanning electron microscopy) observation revealed that the extracted collagen was in the form of fibrils with irregular linkages.     

Calcium ethylenediaminetetraacetate toxicity in the rat: ultrastructural effects on skin collagen

The effect of calcium ethylenediaminetetraacetate (CaEDTA) i.v. infusion on skin ultrastructure was studied in the rat with the aid of transmission electron microscopy. High magnification electron micrographs of collagen fibrils were analysed with a computer aided image analyser, in terms of the Gaussian distribution of fibril diameter and the distance between cross striations of collagen fibrils (D-spacing). CaEDTA caused marked depletion of collagen fibrils in the skin. The collagen fibrils from CaEDTA treated rats exhibited significant increases in D-spacing (about 30%) and diameter (about 40%) compared to saline treated controls. These findings are consistent with earlier published biochemical data indicating that CaEDTA enhances collagen degradation in the rat.     

Demethylavermectins. Biosynthesis, isolation and characterization

Streptomyces avermitilis normally produces eight avermectins. Avermectin A components contain three methoxyl groups; two on the oleandrose disaccharide and one on the aglycone moiety at C5. Avermectin B components contain methoxyl groups only on the oleandrose disaccharide. Sinefungin inhibits methylation at all three sites. Addition of sinefungin to S. avermitilis Agly-1, a mutant which produces virtually only avermectin aglycone A components, alters the fermentation and causes an accumulation of avermectin aglycone B components. Addition of sinefungin to S. avermitilis 08, a high producing strain, results in accumulation of 8 new avermectins which lack methoxyl groups on the oleandrose moieties as well as the aglycone. These new avermectins were isolated and shown to possess anthelmintic and insecticidal activity.     

Microparticles derived from marine sponge collagen (SCMPs): preparation, characterization and suitability for dermal delivery of all-trans retinol.

Collagen microparticles were prepared using marine sponge collagen. For this purpose a previous method by R?ssler et al. (J. Microencapsul. 12 (1995) 49) of emulsification and cross-linking of native calf collagen was modified. The modified method for sponge collagen microparticles (SCMPs) achieved a yield of 10%. Scanning electromicroscopic photographs showed spherical particles with a diameter of 120-300 nm and photon correlation spectroscopic measurements indicated particle size range from 126 (+/-2.9) to 2179 (+/-342) nm. This broad size distribution was caused by some agglomerates that could not be destroyed by ultrasonication. The surface charge was measured as a function of pH. At pH 2.8 the particles were nearly uncharged, at pH 9.0 the particles showed a strong negative charge of about -60 mV. The preformed SCMPs were loaded by adsorption of all-trans retinol. A loading of up to 8% was obtained. Retinol-loaded SCMPs were incorporated into hydrogels and drug stability was investigated. The in vitro penetration of retinol into hairless mice skin in this formulation was compared to retinol formulations without microparticles. The SCMPs had no influence on the chemical stability of retinol in the hydrogel. The dermal penetration of retinol into the skin increased significantly by approximately two-fold.     

河豚鱼皮胶原寡肽的护肤美白功效研究

目的 探究河豚鱼皮胶原寡肽的护肤美白功效。方法 以3个月的雄性豚鼠为试验对象,在豚鼠的背部一侧脱毛处,每天涂抹1次受试物,连续30天。在试验后分别测定豚鼠血清的酪氨酸酶含量,受试皮肤的含水量和羟脯氨酸含量,观察受试皮肤组织形态及黑色素毛囊数,对河豚鱼皮胶原寡肽的护肤美白功效进行评价。 结果 在本试验条件下,受试豚鼠的皮肤无病变现象。河豚鱼皮胶原寡肽能够提高受试豚鼠皮肤的胶原蛋白含量,而且具有抑制皮肤黑色素表达的作用。结论 河豚鱼皮胶原寡肽具有一定的延缓皮肤衰老和美白的功效。     

Calendula extract: effects on mechanical parameters of human skin

The aim of this study was to evaluate the effects of newly formulated topical cream of Calendula officinalis extract on the mechanical parameters of the skin by using the cutometer. The Cutometer 580 MPA is a device that is designed to measure the mechanical properties of the skin in response to the application of negative pressure. This non-invasive method can be useful for objective and quantitative investigation of age related changes in skin, skin elasticity, skin fatigue, skin hydration, and evaluation of the effects of cosmetic and antiaging topical products. Two creams (base and formulation) were prepared for the study. Both the creams were applied to the cheeks of 21 healthy human volunteers for a period of eight weeks. Every individual was asked to come on week 1, 2, 3, 4, 5, 6, 7, and 8 and measurements were taken by using Cutometer MPA 580 every week. Different mechanical parameters of the skin measured by the cutometer were; R0, R1, R2, R5, R6, R7, and R8. These were then evaluated statistically to measure the effects produced by these creams. Using ANOVA, and t-test it was found that R0, and R6 were significant (p <0.05) whereas R1, R2, R5, R7, R8 were insignificant (p > 0.05). The instrumental measurements produced by formulation reflected significant improvements in hydration and firmness of skin.     

Antibiotic A-130, isolation and characterization.

An antibiotic, A-130, was isolated from a strain identified as Streptomyces hygroscopicus, strain A-130. The antibiotic belongs to the nigericin group and like dianemycin, has an alpha, beta-unsaturated ketone chromophore in its molecule. A-130 is active against gram-positive organisms.     

Disposition of cocaine in skin,interstitial fluid,sebum, and stratum corneum

The aim of this study was to determine whether or not the skin acts as a reservoir for cocaine. Cocaine-d5 (1 mg/kg) was administered to five nondependent, cocaine-experienced volunteers. Skin tissue, interstitial fluid, sebum, stratum corneum, and plasma were collected for 72 h after drug administration. Cocaine and benzoylecgonine (BE) levels were determined using GC-MS. Cocaine concentrations peaked in plasma at 1 h after administration, with pharmacokinetic parameters (t(1/2), CL, Vd) also in the expected ranges. In skin, cocaine levels peaked around 1.5 h after administration and became undetectable by 6 h. A correlation was found between the plasma and skin AUC for cocaine (R = 0.99, p = 0.006, N = 4). BE was not detected in skin. In interstitial fluid (N = 4), cocaine concentrations peaked around 5 h after drug administration and were undetectable by 24 h. BE peaks varied between 2 and 24 h and were not detectable at 48 h. In sebum, cocaine levels peaked between 3 and 24 h. BE was found in three samples between 12 and 24 h. In stratum corneum, cocaine was measurable in only one sample from one subject. These findings suggest that skin does not act as a reservoir for cocaine. Rather, cocaine appears to be distributed rapidly to the skin and eliminated, following a time course similar to that of plasma.     

Further isolation and characterization of grammistins from the skin secretion of the soapfish Grammistes sexlineatus.

Soapfishes contain peptide toxins (grammistins) in the skin secretion. Two grammistins (Gs 1 and Gs 2) and six grammistins (Pp 1, Pp 2a, Pp 2b, Pp 3, Pp 4a and Pp 4b) have already been isolated from Grammistes sexlineatus and Pogonoperca punctata, respectively. In this study, five grammistins (Gs A-E), together with grammistins Gs 1 and Gs 2, were further isolated from G. sexlineatus by gel filtration and reverse-phase HPLC. Sequence analyses revealed that grammistins Gs A (28 residues) and Gs C (26 residues) are analogous to grammistin Pp 3 and grammistin Gs B (12 residues) to grammistin Pp 1, while grammistins Gs D (13 residues) and Gs E (13 residues) are identical with grammistins Pp 1 and Pp 2b, respectively. Grammistins Gs A-C exhibited antibacterial activity with a broad spectrum against nine species of bacteria in common with the other grammistins but had no hemolytic activity differing from the other grammistins. Grammistins Gs A-E, Gs 1 and Gs 2 could release carboxyfluorescein entrapped within liposomes made of either phosphatidylcholine or phosphatidylglycerol/phosphatidylcholine (3:1), demonstrating their membrane-lytic activity. However, no clear relationship between the membrane-lytic activity and the biological activity of grammistins was recognized.     

根皮素醇质体的制备、表征及对体外透皮吸收的影响

目的:制备根皮素醇质体,考察醇质体作为根皮素经皮给药载体的可行性.方法:乙醇注入法制备根皮素醇质体.采用包封率和粒径为考察指标,正交试验优化大豆磷脂用量、胆固醇用量、乙醇体积及水浴温度.测定根皮素醇质体粒径分布、多分散指标和Zeta电位,采用Franz扩散池比较根皮素及其醇质体体外透皮特征.结果:根皮素醇质体最佳处方工...     

Arginomycin: production, isolation, characterization and structure

Arginomycin is a new nucleoside antibiotic produced by Streptomyces arginesis. Arginomycin, C18H28N8O5, which inhibits the growth of Gram-positive bacteria and fungi in vitro, is structurally related to blasticidin S and found to be relatively non-toxic.     

Bioactive proteins from marine sponges: Screening of sponge extracts for hemagglutinating, hemolytic, ichthyotoxic and lethal properties and isolation and characterization of hemagglutinins

D. Mebs, I. Weiler and H. F. Heinke. Bioactive proteins from marine sponges: screening of sponge extracts for hemagglutinating, hemolytic, ichthyotoxic and lethal properties and isolation and characterization of hemagglutinins. Toxicon23, 955–962, 1985. — Aqueous extracts of 48 sponge species from the Red Sea, the Australian Barrier Reef and the Florida Keys were screened for hemagglutinating, hemolytic, ichthyotoxic and lethal activities. Forty two per cent of the sponge species exhibited agglutinating properties to human erythrocytes of ABO groups. From four species (Haliclona sp., Cinachyra tenuifolia, Callyspongia viridis, Terpios zetekl) the hemagglutinating factors were isolated by gel filtration and affinity chromatography. A molecular weight of 24,000 was determined for the pure hemagglutinin from Haliclona sp. by SDS electrophoresis and of 22,000 for the semipure hemagglutinin from Cinachyrat tenuifolia by gel filtration. These hemagglutinins were inhibited by d-lactose, but not by d-melibiose or other oligosaccharides, indicating that they may react with terminal d-galactose β1 → 4 residues. The other semipure hemagglutinins were not inhibited by various sugars tested. Hemolytic activity to human erythrocytes was present in about 15% of the sponge extracts, showing a close relationship to ichthyotoxic activity. More than half of the sponge extracts caused toxic symptoms in mice when injected i.p. Using various concentrations death occurred within 12–48 hr. The lethal factors seem to be related to components of low molecular weight in the sponge extracts.     

Extraction,characterization and biocompatibility evaluation of silver carp (Hypophthalmichthys molitrix) skin collagen

Collagen as a biomaterial is commonly obtained from terrestrial animals. However, nowadays, the use of collagen with terrestrial animals' sources due to possible transmission of infectious diseases and religious beliefs is restricted. This study was conducted to evaluate the physicochemical characterization, morphology, and biocompatibility of extracted collagen from silver carp fish skin by-product. Type I collagen was extracted from the silver carp fish skin by-product using acetic acid and pepsin enzyme. The results showed that the extraction yield of ASC and PSC was 43% and 59% (on a dry weight basis), respectively. The presence of two different α-chains confirmed the type I collagen structure for both collagens. Moreover, FTIR spectra investigation demonstrated the triple helical in ASC and PSC collagens. The PSC showed higher imino acids content than ASC. Hence, the fractional viscosity and DSC curves revealed higher denaturation temperature (30 °C), shrinkage temperature (81 °C), and melting temperature (209 °C) for PSC than ASC (29 °C, 77 °C, and 187 °C, respectively). Finally, observations of the microscopic and the cell viability evaluation confirmed biocompatibility and suitable structure to cell growth. Accordingly, the obtained collagen from silver carp fish skin can be a proper alternative for terrestrial animals’ collagen and a safe biomaterial for biomedical use.     

Chaetiacandin, a novel papulacandin. I. Fermentation, isolation and characterization

Chaetiacandin, a new anti-yeast antibiotic structurally related to papulacandin, was isolated from a culture of Monochaetia dimorphospora. The fermentation, isolation, and physico-chemical and biological properties are reported. The molecular formula of this compound was determined as C43H60O16.     

Lavendomycin, a new antibiotic. I. Taxonomy, isolation and characterization

Lavendomycin, a new basic peptide antibiotic containing novel amino acids, has been isolated from the culture broth of a streptomyces designated as Streptomyces lavendulae subsp. brasilicus. The antibiotic obtained as colorless crystals (C29H50N10O8, MW 666) is active against Gram-positive bacteria in vitro and in vivo, however, inactive against Gram-negative bacteria and fungi. An acute toxicity of the antibiotic in mice was LD50 greater than 2 g/kg by subcutaneous injection.