• Title/Summary/Keyword: Pigment reduction

Search Result 100, Processing Time 0.021 seconds

Pigment Reduction to Improve Photosynthetic Productivity of Rhodobacter sphaeroides

  • Kim, Nag-Jong;Lee, Jeong-Kug;Lee, Choul-Gyun
    • Journal of Microbiology and Biotechnology
    • /
    • v.14 no.3
    • /
    • pp.442-449
    • /
    • 2004
  • Improving the light utilization efficiency of photosynthetic cells in photobioreactors (PBRs) is a major topic in algal biotechnology. Accordingly, in the current study we investigated the effect and suitability of photosynthetic pigment reduction for improving light utilization efficiency. The light-harvesting complex II (LH-II) genes of Rhodobacter sphaeroides were removed to construct a mutant strain with less pigment content. The mutant strain exhibited a slower growth rate than the wild-type under a low light intensity, while the mutant grew faster under a high light intensity. In addition, the specific absorption coefficient was lower in the mutant due to its reduced pigment content, thus it seemed that light penetrated deeper into its culture broth. However, the distance (light penetration depth) from the surface of the PBR to the compensation point did not increase, due to an increase in the compensation irradiance of the mutant strain. Experimental data showed that a reduced photosynthetic pigment content, which lessened the photoinhibition under high-intensity light, helped the volumetric productivity of photosynthetic microorganisms.

Nitrate Reduction and Pigment Formation of Chinese-Style Sausage Mixes Caused by Micrococcaceae

  • Guo, H.L.;Chen, M.T.;Liu, D.C.
    • Asian-Australasian Journal of Animal Sciences
    • /
    • v.13 no.8
    • /
    • pp.1173-1177
    • /
    • 2000
  • This study investigated the nitrate reduction ability of Micrococcaceae on pigment formation in Chinese- style sausage. One hundred ppm sodium nitrite and 150 ppm sodium nitrate was added asepticly to ground pork which was then inoculated with $10^7CFU/g$ of either Micrococcus varians, Staphylococcus carnosus or Staphylococcus xylosus. All samples were cured at $20{^{\circ}C}$ or $30{^{\circ}C}$ for 3 days and then color, residue nitrite, nitrosyl pigment and residue nitrate were determined. The results indicated that samples inoculated with S. xylosus had higher a- and b- values due to nitrate reduction and pigment production after 3 days curing and these values were higher at the higher curing temperature. The nitrosyl pigment of the samples with S. xylosus had highest values after 3 days curing at both $20{^{\circ}C}$ and $30{^{\circ}C}$. However, sample inoculated with S. carnosus and S. xylosus had lower nitrate contents than the sample inoculated with M. varians. At $30{^{\circ}C}$ as well as S. carnosus and M. varians had a stronger decreasing in nitrate concentration during curing at $20{^{\circ}C}$. Moreover, samples inoculated with S. xylosus and S. carnosus had a higher residual nitrite content during curing at $20{^{\circ}C}$ or $30{^{\circ}C}$. In conclusion, two Staphylococci strains tested were most optimum starter cultures for improving pigment formation during Chinese-style sausage curing.

Effect of the Amount of Pigment on the Color of Silk Dyed with Fermented Indigo Powder Dye (발효쪽 분말염료로 염색한 견직물의 색소 함량이 직물의 색상에 미치는 영향)

  • Yoo, Wansong;Ahn, Cheunsoon
    • Journal of the Korean Society of Clothing and Textiles
    • /
    • v.42 no.2
    • /
    • pp.342-359
    • /
    • 2018
  • This research investigated the relationship between the amount of fixed pigment and the color of silk dyed with three types of fermented indigo powder dye under different temperatures and pH, by reduction or nonreduction method. Amount of fixed pigment was analyzed using the Ultimate 3000 HPLC-DAD instrument and the color of dyed silk was measured using the X-rite spectrocolorimeter. All silk samples dyed by reduction method showed PB color. The amount of indigotin fixation was dependent on the dyeing temperature and pH regardless of the indigotin composition in the dye. Indirubin was less dependent upon the dyeing condition in the reduction dyeing and its fixation was minimum level. Dyeing conditions which can maximize the indigotin fixation were $50^{\circ}C/pH$ 11 and $70^{\circ}C/pH$ 7 conditions in reduction dyeing. Color of silk showed more redness ($a^*$) thus higher PB color when the indigotin fixation was low and indirubin fixation was relatively high. Indirubin fixation was very low with slightly better fixation by nonreduction method. More reddish color was obtained by nonreduction dyeing, and by more alkaline dyebath.

Determination of Optimal Mixing Ratio of Phosphorescent Pigment to Develop Phosphorescent Paint for Road Line Marking (도로의 축광차선 도료 개발을 위한 축광안료 최적 배합비 산정에 관한 연구)

  • Lee, Yong Mun;Kim, Sang Tae;Kim, Heung Rae
    • International Journal of Highway Engineering
    • /
    • v.17 no.5
    • /
    • pp.67-73
    • /
    • 2015
  • PURPOSES : This study was conducted to derive the optimum mixing ratio of phosphorescent pigment for the development of phosphorescent line marking. METHODS: In this study, we utilized a literature review and case study methodology, to describe the domestic and foreign state of practice for the production and mixing of phosphorescent pigment for use in line marking. The optimal mixing ratio was derived by comparing the reduction in luminance over time for the various phosphorescent pigment mixing ratios identified in the literature. In addition, performance and construction characteristics were analyzed using field testing techniques. RESULTS : The results were as follows: 1) the results of the luminance performance standards tests showed that all of the phosphorescence test specimens satisfied the phosphorescent fire protection standard. As the phosphorescent pigment mixing ratio increased, the luminance value increased, 2) the luminance reduction rate was minimum at the mixing ratio of 50%. However, when compared to a mixing ratio 40%, a small difference was recorded, the luminance reduction rate from the mixing ratio of 40% is judged as being converged. Therefore, in view of the economic efficiency, it was determined that the optimal mixing ratio was 40%, 3) as a result of construction on the field, a mixing ratio of 40% was found to have a higher luminance value than the general line marking for up to three hours after sunset, 4) it was found that the phosphorescent line markings without glass beads spraying had a higher luminance value than the phosphorescent line markings with glass beads spraying. CONCLUSIONS : Through the results of the basic experiments of the line markings obtained by blending a phosphorescent pigment, the results could be applied to play an important role in the development of phosphorescent line marking paint technology and in establishing application planning for on-site construction characteristics.

Stability of Monascin Pigment Isolated from Monascus purpureus (홍국의 황색색소 Monascin에 대한 안정성 연구)

  • 박영현;채지민
    • Journal of Food Hygiene and Safety
    • /
    • v.12 no.1
    • /
    • pp.15-19
    • /
    • 1997
  • The stability of monascin yellow pigment isolated from Monascus purpureus was determined over a period of storage for the wide range of pH, various metal ions and antioxidants. The absorption maximum of monascin pigment was 385 nm. Monascin pigment was more stable in acid solutions than in alkaline (pH 9 and pH 11) during storage period. It was also observed the reduction of absorption was occur after 3 days storage. The stability of monascin pigment was not changed by adding the various metal ions of the concentration of 10-4 M, however, it was unstable by adding the Zn2+, Al3+ and Fe3+ of 103- M concentration. The antioxidants. BHA, BHT, cysteine and L-ascorbic acid, have no effects on the stability of monascin yellow pigment. Thus, it may be concluded that the monascin pigment is stable and useful food additives as the natural colorant except for the alkaline food and food containing the Zn2+, Al3+ and Fe3+.

  • PDF

Particle Size, Morphology and Color Characteristics of C.I. Pigment Red 57:1 : 2. Effect of Salt Milling Process

  • Seo, Hee Sung;Lee, Hyun Kyung;Yoo, Eui Sang
    • Textile Coloration and Finishing
    • /
    • v.27 no.4
    • /
    • pp.245-260
    • /
    • 2015
  • The effect of salt milling process on the crystal size, morphology, and color characteristics of C.I. Pigment Red 57:1 was studied. The primitive morphology and color properties of the pigment after synthesis were studied in the former series work. The size and morphology of primary particles and the second aggregation features should be considered because they are very important to determine pigment quality. We compared the primary morphology of pigment particles before drying with the secondary aggregated morphology of pigment particles after drying and salt milling process. Morphological properties were investigated by particle size analysis, X-ray diffraction, and scanning electron microscopy and color measurement was carried out. Significant reduction in particle size as well as enhanced crystallite size after salt milling process was observed. This result might give a difference in color of the pigment, turning into brighter and more blue-toned red color. It was revealed that synthesis condition affect the morphology and color of the pigment even after milling. Increase in HCl concentration in the synthesis process enhanced crystal size and quality forming bluer-red pigments but an increase in $CaCl_2$ concentration resulted in more amorphous crystals forming darker-red pigments after salt milling.

Activity of $V_2O_5/TiO_2$Catalyst Using Domestic Pigment Titania as Support for Nitric Oxide Reducton (국내 안료용 타이타니아를 담체로 이용한 $V_2O_5/TiO_2$ 촉매상에서 질소산화물 제거활성)

  • 이정빈;이인영;김동화;엄희문;지평삼;추수태;남인식
    • Journal of Korean Society for Atmospheric Environment
    • /
    • v.15 no.6
    • /
    • pp.791-797
    • /
    • 1999
  • The activity of domestic pigment titania$(TiO_2)$ impregnated with vanadia$(V_2O_5)$ was investigated in the laboratory microreactor. The meta-titanic acid$(TiO(OH)_2)$ which was produced at Hankook Titanium was selected as the precursor for support. The domestic pigment $TiO_2$ showed higher activity in the reduction of NO with $NH_3$ than the foreign commercial $TiO_2$. $WO_3$ were added to domestic $V_2O_5/TiO_2$ catalytic system to improve the catalytic activity at higher reaction temperature between 400~50$0^{\circ}C$ Also, the deactivation of domestic $V_2O_5/TiO_2$ and $WO_3-V_2O_5/TiO_2$ catalyst by $SO_2$ and $H_2O$ was investigated.

  • PDF

Effect of Gamma-ray Treatment on Toxicity of Textile and Pigment Wastewaters (감마선 처리가 섬유와 안료폐수의 생물독성에 미치는 영향)

  • Kim, Eun-Ae;Jo, Hun-Je;Park, Eun-Joo;Kim, Hyo-Jin;Kim, Jeong-Gyu;Jung, Jinho
    • Journal of Korean Society on Water Environment
    • /
    • v.22 no.1
    • /
    • pp.145-149
    • /
    • 2006
  • Textile and pigment wastewater samples collected from an industrial complex showed toxic effect on Daphnia magna. For textile wastewater, 48 h acute toxicity of effluent was not detected while toxic unit (TU) of influent was 1.79. The toxicity of influent was completely disappeared by gamma-ray treatment at 10 kGy or by suspended solids (SS) removal. In case of pigment wastewater, both influent and effluent were toxic to D. magna though the effluent satisfied current water quality standards. Gamma-ray treatment had little effect on the toxicity reduction of pigment wastewater since the toxicity was mainly caused by metal ions, in particular, Cr(VI). This work suggests the bioassay technique for monitoring adverse effects of wastewater should be introduced, and also shows the usefulness of gamma-rays as an advanced treatment technique for textile wastewater.

Synthesis and Mechanism of Ni-Doped Hibonite Blue Pigments (Ni-Doped Hibonite 파란색 안료의 합성과 발색기구)

  • Kim, Gumsun;Lee, Byung-Ha
    • Korean Journal of Materials Research
    • /
    • v.24 no.1
    • /
    • pp.43-47
    • /
    • 2014
  • NiO-doped hibonite pigments were synthesized by the solid state method to get stabilized blue color pigment in both oxidation and reduction atmospheres. Optimum substitution condition with NiO for hibonite blue pigment was investigated. Experimental results were comparable to those of previous cobalt-minimization studies performed with other phosphate- or oxide-based cobalt-containing ceramic pigments (having olivine ($Co_2SiO_4$), spinel ($CoAl_2O_4$), or with co-doped willemite ($(Co,Zn)_2SiO_4$) structures). Composition was designed varying the NiO molar ratio increasing with $SnO_2$. The optimum substitution content is 0.93 mole NiO with 0.75mole $SnO_2$. The characteristics of the synthesized pigment were analyzed by XRD, Raman spectroscopy, SEM, and UV-vis. Synthesized pigment was applied to a lime-barium glaze with 10 wt% each and fired at an oxidation atmosphere of $1250^{\circ}C/1h$ and a reducing atmosphere $1240^{\circ}C/1h$. Blue color was obtained with $L^*a^*b^*$ values at 43.39, -6.78, -18.20 under a reducing atmosphere and 41.66, -6.36, -14.7 under and oxidation atmosphere, respectively.

A Pilot Study of Skin Resurfacing Using the 2,790-nm Erbium:YSGG Laser System

  • Rhie, Jong Won;Shim, Jeong Su;Choi, Won Seok
    • Archives of Plastic Surgery
    • /
    • v.42 no.1
    • /
    • pp.52-58
    • /
    • 2015
  • Background The erbium:yttrium scandium gallium garnet (Er:YSGG) laser differs from other laser techniques by having a faster and higher cure rate. Since the Er:YSGG laser causes an appropriate proportion of ablation and coagulation, it has advantages over the conventional carbon dioxide ($CO_2$) laser and the erbium-doped yttrium aluminum garnet (Er:YAG) laser, including heating tendencies and explosive vaporization. This research was conducted to explore the effects and safety of the Er:YSGG laser. Methods Twenty patients participated in the pilot study of a resurfacing system using a 2,790-nm Er:YSGG laser. All patients received facial treatment by the 2,790-nm Er:YSGG laser system (Cutera) twice with a 4-week interval. Wrinkle reduction, reduction in pigment inhomogeneity, and improvement in tone and texture were measured. Results Study subjects included 15 women and five men. Re-epithelization occurred in all subjects 3 to 4 days after treatment, and wrinkle reduction, reduction in pigment inhomogeneity, and improvement in tone and texture within 6 months of treatment. Conclusions The 2,790-nm YSGG laser technique had fewer complications and was effective in the improvement of scars, pores, wrinkles, and skin tone and color with one or two treatments. We expect this method to be effective for people with acne scars, pore scars, deep wrinkles, and uneven skin texture and color.