Identification of an anthraquinone pigment and a hydroxystilbene antibiotic from Xenorhabdus luminescens

The entomopathogenic bacterium Xenorhabdus luminescens produces a red pigment and an antibiotic in insect carcasses in which it grows and in axenic cultures. The pigment was purified and identified as the anthraquinone derivative 1,6-dihydroxy-4-methoxy-9,10-anthraquinone, which exhibits a pH-sensitive color change, i.e., it is yellow below pH 9 and red above pH 9. The antibiotic was also purified and identified as the hydroxystilbene derivative 3,5-dihydroxy-4-isopropylstilbene.     

Isolation and identification of the urinary pigment uroerythrin.

The red pigment uroerythrin, a chromophore known to be adsorbed by the amorphous urate sediments (sedimentum lateritium), has been isolated from human urine and further purified as its trimethyl derivative. Urine was applied to a column of Amberlite XAD-2 resin on which uroerythrin and other pigments were adsorbed. The pigments were eluted with methanol and uroerythrin was further purified by extraction with ether at pH 4.0, repeated chromatography on lipophilic Sephadex LH-20 and thin-layer chromatography on silica gel. For optimal purification uroerythrin was converted into the trimethyl derivative and chromatographed on silical gel thin-layer plates. The structure of the pigment has been studied by chromate degradation followed by identification of the imide products by thin-layer chromatography. From these results and from infrared, mass spectral and nuclear magnetic resonance data a tripyrrole structure for uroerythrin is concluded. The proposed structure for the chromophore is related to that of the bile pigment biliverdin consisting, however, only of the rings A, B and C.     

HP17, a new pigment-like antibiotic produced by a new strain of Spirillospora

Spirillospora strain 719 produces several antibiotics. On solid and liquid media, a deep red pigment is formed and diffuses throughout the culture. It was extracted with methanol from the mycelium cake and from the fermentation broth after precipitation at pH 2 and purified using TLC and HPLC. Its u.v. absorption spectrum and its physicochemical characteristics place this antibiotic in the 3.3.2.2.8 of the Berdy et al. classification. In most respects, it resembles proteinaceous pigment from Spirillospora 1655 and 1309-b that was studied and named spirillomycin. However, HP17 differs from spirillomycin principally in molecular weight and chemical nature.     

Isolation and Identification of Canthaxanthin from Micrococcus roseus

Cooney, J. J. (University of Dayton, Dayton, Ohio), H. W. Marks, Jr., and Anne M. Smith. Isolation and identification of canthaxanthin from Micrococcus roseus. J. Bacteriol. 92:342-345. 1966.-The principal colored carotenoid of Micrococcus roseus was purified by solvent partitioning followed by column and thin-layer chromatography. Absorption spectra, partition coefficients, and infrared spectra suggested that the pigment was a diketo derivative of beta-carotene. The pigment was subjected to reduction, and the reduced pigment was subsequently dehydrated. Spectral data and partition coefficients of these derivatives indicated that the original pigment was canthaxanthin (4',4'-diketo-beta-carotene). The pigment was an all-trans isomer; it does not exist as an ester in M. roseus. Canthaxanthin has not previously been identified as a bacterial pigment.     

雪白白僵菌红色素的初步鉴定及其与环孢菌素A对底物缬氨酸的竞争

【目的】分离鉴定雪白白僵菌红色素,分析红色素与环孢菌素A对底物缬氨酸的竞争和相互影响。【方法】对红色素进行分离纯化,利用UV、IR和ESI-MS对红色素进行初步鉴定。采用缬氨酸分批补料培养,通过控制溶氧水平,以及添加红色素,分析红色素与环孢菌素A合成之间的竞争关联及相互影响。【结果】经鉴定,雪白白僵菌红色素分子式为C15H10O5,推测为含有芳环结构的蒽醌类化合物。在补加缬氨酸和高DO条件下,环孢菌素的产量高于低DO水平,相反红色素在低DO条件下合成量大于高DO水平。在不补加缬氨酸条件下,实验结果与补加缬氨酸培养一致,但是红色素和环孢菌素A的产量都显著降低。进一步添加外源纯化的红色素时,随着添加量的增加出现了环孢菌素A合成先减弱后增加的变化。【结论】发现并证实了雪白白僵菌红色素与环孢菌素A合成都以缬氨酸为共同底物,但两者的途径又相互独立。     

Propionibacterium jensenii produces the polyene pigment granadaene and has hemolytic properties similar to those of Streptococcus agalactiae

The red polyene pigment granadaene was purified and identified from Propionibacterium jensenii. Granadaene has previously been identified only in Streptococcus agalactiae, where the pigment correlates with the hemolytic activity of the bacterium. A connection between hemolytic activity and the production of the red pigment has also been observed in P. jensenii, as nonpigmented strains are nonhemolytic. The pigment and hemolytic activity from S. agalactiae can be extracted from the bacterium with a starch extraction solution, and this solution also extracts the pigment and hemolytic activity from P. jensenii. A partial purification of the hemolytic activity was achieved, but the requirement for starch to preserve its activity made the purification unsuccessful. Partially purified hemolytic fractions were pigmented, and the color intensity of the fractions coincided with the hemolytic titer. The pigment was produced in a soluble form when associated with starch, and the UV-visual spectrum of the extract gave absorption peaks of 463 nm, 492 nm, and 524 nm. The pigment could also be extracted from the cells by a low-salt buffer, but it was then aggregated. The purification of the pigment from P. jensenii was performed, and mass spectrometry and nuclear magnetic resonance analysis revealed that P. jensenii indeed produces granadaene as seen in S. agalactiae.     

产紫青霉突变菌株Li-3-9的发酵条件优化及红色素安全性评价

本实验对前期研究得到的具有高产红色素能力的产紫青霉突变菌株Penicillium purpurogenum Li-3-9的发酵条件进行优化的同时作出了对红色素的安全性评价。在单因素试验的基础上,采用Box-Behnken试验设计优化了蔗糖浓度、酵母膏浓度和装液量对红色素色价的影响;并且研究了P. purpurogenum Li-3-9产生的红色素对斑马鱼胚胎的毒性效应。结果表明,最佳发酵条件为：蔗糖40g/L、酵母膏4g/L、装液量为45mL、接种量4%、培养温度32℃、初始pH值6.9、培养时间168h、摇床转速150r/min,红色素色价最高达到了11.4U/mL。通过计算斑马鱼胚胎致死率、心率、畸形率及孵化率可知,该色素无致死毒性,并且对斑马鱼胚胎发育具有一定的促进作用。     

4-Hydroxyretinal, a new visual pigment chromophore found in the bioluminescent squid, Watasenia scintillans

The bioluminescent squid, Watasenia scintillans has three visual pigments. The major pigment, based on retinal (lambda max 484 nm), is distributed over the whole retina. Another pigment based on 3-dehydroretinal (lambda max approximately 500 nm) and the third pigment (lambda max approximately 470 nm) are localized in the specific area of the ventral retina just receiving the downwelling light. Visual pigment was extracted and purified from the dissected retina. The chromophores were then extracted and analyzed with HPLC, NMR, infrared and mass spectroscopy, being compared with the synthetic 4-hydroxyretinal. A new retinal derivative, 11-cis-4-hydroxyretinal, is identified as the chromophore of the third visual pigment of the squid.     

Wounding- and Elicitor-induced Formation of Coloured Chalcones and Flavans (as Phytoalexins) in Hippeastrum x hortorum*

Hippeastrum x hortorum bulbs produce red pigments upon wounding. Analysis by TLC, HPLC, MS and NMR revealed that this pigment, which is absent in unwounded tissue, is a mixture composed of an orange-coloured chalcone (3,2′4′-trihydroxy-4-methoxychalcone) and 3 flavans (7,4′-dihydroxy-8-methylflavan, 7,3′-dihydroxy-4′-methoxyflavan and 7-hydroxy-3′-4′-methylenedioxyflavan). The colourless flavans can be oxidised to red-coloured dimers or polymers. The induction of these “phytoalexins” is achieved by wounding and can be further amplified by biotic and abiotic elicitors; e.g. cell walls of yeast appeared to be a potent elicitor. Immediately after wounding or elicitation the apparent activities of phenylalanine ammonium lyase (PAL) and peroxidase, which are probably involved in the biosynthesis of the red pigments increase substantially (both enzymes are hardly measurable in unwounded tissue) and reach a transient maximum after 2 ? 3d whereas pigment formation becomes visible after 2d and reaches a maximum after 9 to 12 d. Since cycloheximide inhibits the formation of the phytoalexins, a de novo synthesis of the corresponding enzymes is likely. Total phytoalexin extracts showed an inhibition of bacterial growth (e.g. of Bacillus subtilis, B. megaterium) and of feeding by polyphagous larvae of the moth Syntomis mogadorensis. These data imply that the wounding- and elicitor-induced phytoalexins appear to function as defence compounds against microorganisms and herbivores.     

Formation of the blue pigment indigoidine by phytopathogenic erwinia

Most cultures belonging to the “Erwinia chrysanthemi group” of soft-rot bacteria form traces of a blue, extracellular, water-insoluble pigment. This pigment is generally not found in cultures of the other members of the genus Erwinia. The blue substance has been isolated and purified from three members of the E. chrysanthemi group; it has been identified as indigoidine, 5,5′-diamino-4,4′-dihydroxy-3,3′-diazadiphenoquinone-(2,2′).     

Production of red pigment by submerged culture of Paecilomyces sinclairii

AIMS: From a survey of submerged culture of edible mushrooms, a high pigment-producing fungus Paecilomyces sinclairii was selected and its optimal culture conditions investigated. METHODS AND RESULTS: The optimal culture conditions for pigment production were as follows: inoculum age, 3 d; temperature, 25 degrees C; initial pH, 6.0; carbon source, 1.5% (w/v) soluble starch; nitrogen source, 1.5% (w/v) meat peptone. Although addition of 10 mmol l(-1) CaCl2 to the culture medium slightly increased pigment production, most of the bio-elements examined had no notable or detrimental effect on pigment production. CONCLUSIONS: Under the optimal conditions obtained in the flask culture tested, a ninefold increase in pigment production (4.4 g l(-1)) was achieved using a 5(-l) batch fermenter. Paecilomyces sinclairii secreted water-soluble red pigment into the culture medium. The pigment colour was strongly dependent on the pH of the solution: red at pH 3-4, violet at pH 5-9 and pink at pH 10-12. SIGNIFICANCE AND IMPACT OF THE STUDY: The high concentration of pigment (4.4 g l(-1)) produced by P. sinclairii demonstrates the possibility of commercial production of pigment by this strain, considering its relatively high production yield and light stability.     

Propionibacterium jensenii Produces the Polyene Pigment Granadaene and Has Hemolytic Properties Similar to Those of Streptococcus agalactiae

The red polyene pigment granadaene was purified and identified from Propionibacterium jensenii. Granadaene has previously been identified only in Streptococcus agalactiae, where the pigment correlates with the hemolytic activity of the bacterium. A connection between hemolytic activity and the production of the red pigment has also been observed in P. jensenii, as nonpigmented strains are nonhemolytic. The pigment and hemolytic activity from S. agalactiae can be extracted from the bacterium with a starch extraction solution, and this solution also extracts the pigment and hemolytic activity from P. jensenii. A partial purification of the hemolytic activity was achieved, but the requirement for starch to preserve its activity made the purification unsuccessful. Partially purified hemolytic fractions were pigmented, and the color intensity of the fractions coincided with the hemolytic titer. The pigment was produced in a soluble form when associated with starch, and the UV-visual spectrum of the extract gave absorption peaks of 463 nm, 492 nm, and 524 nm. The pigment could also be extracted from the cells by a low-salt buffer, but it was then aggregated. The purification of the pigment from P. jensenii was performed, and mass spectrometry and nuclear magnetic resonance analysis revealed that P. jensenii indeed produces granadaene as seen in S. agalactiae.     

Induction of Red Color Formation in Cabbage Juice by Lactobacillus brevis and Its Relationship to Pink Sauerkraut

Membrane-filtered cabbage juice, when fermented by Lactobacillus brevis under conditions of controlled pH, frequently produced a water-soluble red pigment. The pigment, presumably responsible for imparting a highly objectionable discoloration to sauerkraut, was formed during the post logarithmic phase of growth. Color development is pH dependent (5.2 to 6.3) and can be suppressed by chemical reductants or anaerobic conditions of growth. The compound responsible for discoloration was purified and partially characterized.     

Hypoxylone,a naphthyl-naphthoquinone pigment from the fungus Hypoxylon sclerophaeum

Hypoxylone, the stromal pigment ofHypoxylon sclerophaeum was isolated and identified as 5-hydroxy-2- (1′,8′-dihydroxy-4′-naphthyl)-1,4-naphth     

Identification of the blue pigment formed in a D-glucose-glycine reaction system

D-Glucose (0.7 M), glycine (0.3 M), and sodium hydrogencarbonate (0.1 M) were dissolved in aqueous 30% ethanol at pH 8.0 and left at 50 °C for 4 d in a dark room under nitrogen displacement. The resulting blue pigment was isolated and purified from the blue solution by anionic exchange and gel filtration chromatography. This blue pigment, which is designated Blue-G1, was identified as 5-[1,4-bis-carboxymethyl-5-(2,3,4-trihydroxybutyl)-1,4-dihydropyrrolo[3,2-b]pyrrol-2-ylmethylene]-1,4-bis-carboxymethyl-2-(2,3,4-trihydroxybutyl)-4,5-dihydropyrrolo[3,2-b]pyrrol-1-ium. Blue-G1 had two symmetrical pyrrolopyrrole structures with a trihydroxybutyl group. Blue-G1 had a polymerizing activity, suggesting it to be an important Maillard reaction intermediate through the formation of melanoidins.     

Metabolism of prostaglandins D2 and F2 alpha in primary cultures of rat hepatocytes

3H-Labeled prostaglandins D2 and F2 alpha rapidly degraded to more-polar metabolites in primary cultured rat hepatocytes. The metabolites of prostaglandins D2 and F2 alpha accumulated in the culture medium. The metabolites extracted by ethyl acetate at pH 3 were purified by silicic acid column and thin-layer chromatography of silica gel, and were analysed by gas chromatography-mass spectrometry. The major metabolites from prostaglandin D2 were identified as dinor-prostaglandin D1 (7 alpha,13-dihydroxy-9-ketodinorprost-11-enoic acid) and tetranor-prostaglandin D1 (5 alpha,11- dihydroxy-7-ketotetranorprost-9-enoic acid). Those from prostaglandin F2 alpha were identified as dinor-prostaglandin F1 alpha (7 alpha,9 alpha,13-trihydroxydinorprost-11-enoic acid), tetranor-prostaglandin F1 alpha (5 alpha,7 alpha,11-trihydroxytetranorprost-9-enoic acid) and 9 alpha,11 alpha,15-trihydroxyprost-13-ene-1,20-dioic acid. These data indicate that prostaglandins D2 and F2 alpha mainly degraded by beta-oxidation, which is the same process as reported earlier for prostaglandins E1 and E2, and that prostaglandin F2 alpha was also subjected to omega-oxidation.     

A simple method for efficient extraction and purification of C-phycocyanin from Spirulina platensis Geitler

Phycocyanin is a major light harvesting accessory pigment of red algae and cyanobacteria. In the light of its many commercial applications in food and pharmaceutical industry, purity of the pigment plays a major role. Pharmaceutical industry demands a highly pure phycocyanin with A620/280 ratio of 4 and food industry a ratio of 2. In the present study phycocyanin was extracted in sodium phosphate buffer (pH 7) after macerating in liquid nitrogen. The crude phycocyanin thus extracted was precipitated with 50% ammonium sulphate, purified by dialysis and finally by gel filtration chromatography. Pure phycocyanin was finally obtained with an A620/A280 value of 4.98.     

On the preparation of indoxyl red from indican and some new characteristics

An indole compound with a strong purple–red color was produced by boiling a solution of indican under acidic conditions and purified by chromatographies on DEAE-650S Toyopearl TSK-gel and silica-gel columns. The purple-red compound purified was identified as indoxyl red, on the basis of FAB Mass, ¹³C NMR, ¹H NMR, UV–visible spectra, and IR spectra. Although indoxyl red was first synthesized by Seidel⁹ 70 years ago, very little information has been available on its characteristics. We repot here that the compound was purple-red colored at acidic pH and green at pH 13, and showed antiproliferative and cytotoxic activities to the mouse B cell lymphoma cell line NSF202.     

Arrangement of the disulphide bridges in human low-Mr kininogen.

Transposon mutant strains which were affected in bile acid catabolism were isolated from four Pseudomonas spp. Two of the mutant groups isolated were found to accumulate 12 alpha-hydroxyandrosta-1,4-diene-3,17-dione as the major product from deoxycholic acid. Strains in one of these two groups were able to grow on steroids such as chenodeoxycholic acid, which lacks a 12 alpha-hydroxy function, whereas the one member of the second group could not. With chenodeoxycholic acid, this latter strain accumulated a yellow muconic-like derivative, tentatively identified as 3,7-dihydroxy-5,9,17-trioxo-4(5),9(10)-disecoandrosta-1(10)2 -dien-4-oic acid. Members of two further mutant groups accumulated either 12 beta-hydroxyandrosta-1,4-diene-3,17-dione or 3,12 beta-dihydroxy-9(10)-secoandrosta-1,3,5(10)-triene-9,17-dione as the major product from deoxycholic acid. The relationship between the catabolism of m- and p-cresol, 3-ethylphenol and the bile acids was also examined.     

The effect of red pigment of Saccharomyces cerevisiae on insulin fibril formation in vitro

The effect of the yeast red pigment, the result of polymerization of AIR, and of its low molecular weight derivative (presumably devoid of phosphoribosyl moiety) on the formation of amyloid fibrils in vitro was studied. Both the red pigment and its derivative, the result of acid hydrolysis of the original pigment, were shown to diminish the intensity of amyloid bound Thioflavine T fluorescence. Correlation between the decrease of the intensity of Thioflavine T fluorescence and the concentration of both forms of the red pigment was demonstrated. Both forms were also able to compete with Thioflavine T for amyloid fibrils. Electron microscopy permitted to visualize a drop of fibril size in the case of red pigments presence during their formation.