Identification of a black yeast isolated from oak bark as belonging to the genus Phaeococcomyces sp. Analysis of melanin produced by the yeast

1989 ◽  
Vol 35 (7) ◽  
pp. 728-734 ◽  
Author(s):  
M. J. Butler ◽  
G. Lazarovits ◽  
V. J. Higgins ◽  
M.-A. Lachance
Keyword(s):  
Culture Media ◽  
Average Diameter ◽  
Stationary Growth Phase ◽  
Oxidation Products ◽  
Black Yeast ◽  
Growth Media ◽  
Melanin Production ◽  
Melanin Pigmentation ◽  
Low Levels ◽  
Melanin Pathway

A black fungus isolated from oak bark was identified as a member of the yeast-like genus Phaeococcomyces. While no sexual reproduction was observed, the isolate showed characteristics associated with basidiomycetous yeasts: it was non-fermentative, produced extracellular urease, was positive with the diazonium blue B colony colour test, and had an enteroblastic form of budding. The isolate produced a black pigment constitutively which was shown to be a melanin. Production of the pigment was inhibited by the incorporation of low levels of the fungicide tricyclazole in growth media, inidicating that it was a pentaketide melanin. Pigmentation mutants were produced. Albino mutants did not produce melanin. Diffusion mutants accumulated the pentaketide melanin pathway oxidation products flaviolin and 2-hydroxyjuglone in culture media. Cross-feeder mutants accumulated scytalone, a pentaketide melanin pathway intermediate, in culture media, and caused albino mutants to melanize when grown in proximity to them on agar plates. A single mutant was isolated which excreted 1,8-dihydroxy naphthalene, the end product of the pathway. Broth cultures of Phaeococcomyces sp. in stationary growth phase released melanin in the form of granules, with an average diameter of 30 nm.Key words: black yeast, melanin production, Phaeococcomyces sp.

scholarly journals Characterization and Lipolytic Activity of Bacteria Isolates from Freshwater Clam (Mercenaria Mercenaria) in Bayelsa State, Nigeria

2020 ◽  
pp. 1-4
Author(s):  
Opara C N ◽  
◽  
Anumudu C K ◽  
Keyword(s):  
Protein Content ◽  
Culture Media ◽  
Lipolytic Activity ◽  
Cell Mass ◽  
Mercenaria Mercenaria ◽  
Total Protein Content ◽  
Growth Media ◽  
Pseudomonas Sp ◽  
Bacillus Sp ◽  
Freshwater Clam

Lipases form an important group of relevant enzymes which have applications in various fields including; food, pharmaceutical, detergent, textile and cosmetic industries. Lipases can be produced from diverse sources including microorganisms. This study evaluated the potential of bacteria isolates from fresh-water clam Mercenaria Mercenaria to produce lipolytic enzymes. Ten samples of Clam (Mercenaria Mercenaria) were screened for the presence of lipase producing bacteria using classical culture methods. Eleven bacteria species were obtained, of which six (Actinomyces sp., E. coli, Bacillus sp., Pseudomonas sp., Clostridium sp. and Klebsiella sp.) produced lipases that had lipolytic activity in breaking down olive oil used in media supplementation. The best culture media and conditions for optimal production of lipases was studied and it was shown that supplementation of growth media with 2% dextrose at neutral pH gave the greatest yield of lipases when lipase producing isolates were grown in shake flasks. Measurement of biomass by culture and turbidimetric methods indicates that the highest cell mass was recorded by Pseudomonas sp at 7.8 x 105 CFU/ml, closely followed by Actinomyces sp. and Bacillus sp., at 6.2 x 105 CFU/ml and 5.3 x 105 respectively. The produced lipases were partially purified by precipitating with ammonium sulphate followed by dialysis. The total protein content of produced lipases was evaluated by the Lowry’s method, showing that estimated protein content followed the same trend as cell biomass with the highest recorded by Pseudomonas sp. at 1.53mg/ml, followed by Actinomyces sp. and Bacillus sp. at 1.47mg/ml and 1.32mg/ml respectively. The results obtained in this study shows that isolates obtained from freshwater clam can produce potent lipases which can be employed for industrial, food and other diverse uses

scholarly journals BCG Substrains Change Their Outermost Surface as a Function of Growth Media

Vaccines ◽  
2021 ◽  
Vol 10 (1) ◽  
pp. 40
Author(s):  
Sandra Guallar-Garrido ◽  
Farners Almiñana-Rapún ◽  
Víctor Campo-Pérez ◽  
Eduard Torrents ◽  
Marina Luquin ◽  
...  
Keyword(s):  
Culture Media ◽  
Chemical Properties ◽  
Growth Conditions ◽  
Neutral Red ◽  
Culture Conditions ◽  
Host Cells ◽  
Growth Media ◽  
Phenotypic Characteristics ◽  
Outermost Surface ◽  
Red Dye

Mycobacterium bovis bacillus Calmette-Guérin (BCG) efficacy as an immunotherapy tool can be influenced by the genetic background or immune status of the treated population and by the BCG substrain used. BCG comprises several substrains with genetic differences that elicit diverse phenotypic characteristics. Moreover, modifications of phenotypic characteristics can be influenced by culture conditions. However, several culture media formulations are used worldwide to produce BCG. To elucidate the influence of growth conditions on BCG characteristics, five different substrains were grown on two culture media, and the lipidic profile and physico-chemical properties were evaluated. Our results show that each BCG substrain displays a variety of lipidic profiles on the outermost surface depending on the growth conditions. These modifications lead to a breadth of hydrophobicity patterns and a different ability to reduce neutral red dye within the same BCG substrain, suggesting the influence of BCG growth conditions on the interaction between BCG cells and host cells.

scholarly journals Effective medium for in vitro sprouting of the buds and multiplication of the plantlets, and identification of the fungal contaminant associated with the explants of Gnetum

2021 ◽  
Vol 16 (2) ◽  
pp. 001-013
Author(s):  
Abwe Mercy Ngone ◽  
Lawrence Monah Ndam ◽  
Rita Mungfu Njilar ◽  
Doungous Oumar ◽  
Thomas Eku Njock
Keyword(s):  
Culture Medium ◽  
Culture Media ◽  
Fungal Growth ◽  
Growth Media ◽  
Fungal Contamination ◽  
Surface Sterilization ◽  
Pure Cultures ◽  
Nodal Cuttings ◽  
Baseline Information

Plant tissue culture requires the optimization of growth media. Gnetum, known locally in Cameroon as “Eru” is an indigenous gymnospermous vegetable with diverse medicinal, nutritional, cultural and socio-economic values. This resource is over-exploited and expected to neighboring countries, resulting to increased scarcity in the forest. Preliminary work on the in vitro culture of nodal cuttings was faced by the problem of fungal contamination. It was therefore necessary to isolate and identify the fungal contaminant, optimize the surface sterilization of field material and compose an appropriate medium for sprouting. Pure cultures of the fungus were obtained and grown on Potato Dextrose Agar (PDA) and Sabouraud Dextrose Agar (SDA). The identification was based on the appearance of the fungal growth on plates and also on the microscopic view. This was affected by the use of keys. Gnetum explants were disinfected with the various concentrations of disinfectants, preceded in some instances by pre-treatments, as well as incorporating fungicides in the culture medium. Two different culture media were employed: the Woody Plant Medium (WPM) and the Murashige and Skoog (MS) based establishment medium (Y-1). Gnetum was found to live in association with a complex of Microsporum species. The level of contamination of cultures was reduced from 100% to 40% when pre-treated before disinfection and even lower to 10% by incorporating fungicides in the medium. Sprouting was observed in WPM. This study provides baseline information on the in vitro propagation of Gnetum and thus opens up avenues for more research to be carried out in this field.

Abstract 132: A Novel Hydrogen Sulfide (H 2 S) Prodrug, SG1002, Protects Against Myocardial Oxidative Damage and Hypertrophic Signaling via Induction of Cystathionine Β-Synthase (CBS) and Antioxidant Proteins

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Kazi N Islam ◽  
Erminia Donnarumma ◽  
Erinn Donnelly ◽  
David J Lefer
Keyword(s):  
Oxidative Stress ◽  
Clinical Utility ◽  
Culture Media ◽  
Therapeutic Strategies ◽  
Oxidation Products ◽  
Cellular Damage ◽  
Serum Starvation ◽  
Antioxidant Proteins ◽  
Hypertrophic Signaling ◽  
Cells Cultured

Background: Endogenously produced H 2 S is critical for cardiovascular homeostasis. Therapeutic strategies aimed at increasing H 2 S levels have proven cardioprotective in models of acute myocardial infarction and heart failure (HF). The present study was under taken to investigate the effects of a novel H 2 S prodrug, SG1002, on stress induced hypertrophic signaling in murine HL1 cardiomyocytes. Methods: HL1 cells were maintained either in serum starvation (1%) or serum containing (10%) media followed by treatment either with SG1002 or H 2 O 2 , or endothelin-1 (ET-1)/phenylephrine (Phe) or in combination. Treated cells were analyzed for specific experimental needs. Results: SG1002 significantly increased cellular levels of the H 2 S producing enzyme, CBS, as well as production of H 2 S and nitrosothiol in HL1 cells cultured both in serum starvation or serum containing media. SG1002 significantly inhibited H 2 O 2 and ET-1/Phe induced oxidative stress in both culture media as measured by advanced protein oxidation products and MDA levels. Expression of ANP and BNP were markedly attenuated by SG1002 treatment. Cells cultured in media supplemented with serum containing H 2 O 2 /(ET-1 or Phe) or in 1% serum exhibited decreased levels of CBS, SOD1, and catalase. When the HL1 cells were coincubated with SG1002 cellular damage from oxidative stress was significantly attenuated accompanied by an increase in CBS expression. Conclusion: Our data clearly demonstrate that SG1002 attenuates myocardial cellular damage via increasing antioxidant proteins. SG1002 directly increases H 2 S levels and upregulates CBS. Studies are currently underway to evaluate the clinical utility of SG1002 in HF.

In vitro culture and non-invasive metabolic profiling of single bovine embryos

2019 ◽  
Vol 31 (2) ◽  
pp. 306
Author(s):  
Monika Nõmm ◽  
Rando Porosk ◽  
Pille Pärn ◽  
Kalle Kilk ◽  
Ursel Soomets ◽  
...  
Keyword(s):  
Molecular Weight ◽  
Metabolic Profiling ◽  
Culture Medium ◽  
Culture Media ◽  
Blastocyst Stage ◽  
Growth Media ◽  
Low Molecular Weight ◽  
Bovine Embryos ◽  
Non Invasive

Selecting high-quality embryos for transfer has been a difficult task when producing bovine embryos invitro. The most used non-invasive method is based on visual observation. Molecular characterisation of embryo growth media has been proposed as a complementary method. In this study we demonstrate a culture medium sampling method for identifying potential embryonic viability markers to predict normal or abnormal embryonic development. During single embryo culture, 20µL culture media was removed at Days 2, 5 and 8 after fertilisation from the same droplet (60µL). In all, 58 samples were analysed using liquid chromatography–mass spectrometry. We demonstrate that it is possible to remove samples from the same culture medium droplets and not significantly affect blastocyst rate (25.2%). Changes in any single low molecular weight compound were not predictive enough. Combining multiple low molecular weight signals made it possible to predict Day 2 and 5 embryo development to the blastocyst stage with an accuracy of 64%. Elevated concentrations of lysophosphatidylethanolamines (m/z=453, 566, 588) in the culture media of Day 8 well-developing embryos were observed. Choline (104m/z) and citrate (215m/z) concentrations were increased in embryos in which development was retarded. Metabolic profiling provides possibilities to identify well-developing embryos before transfer, thus improving pregnancy rates and the number of calves born.

scholarly journals The Modification of Factor VIII Procoagulant Activity in Tissue Culture Media Supplemented with Fetal Calf Serum

1977 ◽  
Author(s):  
Nancy W. Stead ◽  
P. A. McKee
Keyword(s):  
Endothelial Cells ◽  
Factor Viii ◽  
Fetal Calf Serum ◽  
Culture Media ◽  
Umbilical Vein ◽  
Calf Serum ◽  
Procoagulant Activity ◽  
Growth Media ◽  
Tissue Culture Media ◽  
Plasma Factor

Cultured human umbilical vein endothelial cells produce a protein that reacts with rabbit antibody to purified plasma factor VIII (FVIII)/von Willebrand factor (vWF) and has vWF activity, but not FVIII procoagulant activity (PCA) (Jaffe et al. JCI 52: 2757, 1973) . In our laboratory endothelial cell cultures produce vWF activity that increases to 3 µg/culture by 72 hrs; partially purified protein from culture media forms an immunoprecipitin line of identity with human, but not bovine, plasma FVIII/vWF. Of the 3 functions of plasma FVIII/vWF protein, PCA, but not vWF activity or antigenicity, is modified by trace proteases. An assay that measures hydrolysis of p-nitroaniline from the tripeptide Bz-phe-val-arg-p-nitroanilide detects trace proteases in growth media; 0.001 NIH u thrombin releases measurable quantities of p-nitroaniline. Culture media without fetal calf serum (FCS) did not hydrolyze the tripeptide. Media 20% in: FCS, FCS heated to 56° for 30 min, FCS made 1.7×10-3M diisopropylfluorphosphate (DFP), FCS and 4.4x10-8 moles soybean trypsin inhibitor, or FCS and 4.4xl0-8 moles Trasylol releases 3.5x10-6, 3.6x10-7, 3.6xl0-7, 3.5xl0-6 and 2.8xl0-6 mmole of p-nitroaniline per ml of media per min. PCA of FVIII/vWF molecule is measured by one stage (PCA1) and two stage (PCA2) assays. Although >85% PCA1 or PCA2 of purified plasma FVIIl/vWF added to media without FCS remains at 6 hours, varying amounts of PCA1 and only 10% PCA2 of the FVIII/vWF added to media 20% in FCS remained in 6 hrs. Hence endothelial cells make a protein with vWF activity and FVIII/vWF antigenicity; but were the protein to have PCA at the time of release, trace proteases in the growth media could quickly destroy it.

scholarly journals Micropropagation and Production of Health Promoting Lignans in Linum usitatissimum

Plants ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 728
Author(s):  
Irfan Khan ◽  
Mubarak Ali Khan ◽  
Muhammad Amir Shehzad ◽  
Amir Ali ◽  
Sher Mohammad ◽  
...  
Keyword(s):  
Linum Usitatissimum ◽  
Culture Media ◽  
Radical Scavenging Activity ◽  
Radical Scavenging ◽  
Total Phenolic ◽  
Growth Media ◽  
Shoot Cultures ◽  
Market Demand ◽  
Pharmacologically Active

Linum usitatissimum commonly known as flax or linseed is an important medicinal plant, produces medicinally potent lignans, used in the treatment of several human diseases. Lignans limited production in the natural plants does not meet the increasing market demand. This study was conducted to establish an easy and rapid method for the in vitro micropropagation and production of potent lignans and antioxidant secondary metabolites in linseed. The results indicated that hypocotyl explants under the effects of thidiazuron (TDZ: 0.5 mg/L) + kinetin (Kn: 0.5 mg/L) in the basal growth media, resulted in the optimal shoot organogenesis parameters (shoot induction frequency: 86.87%, number of shoots: 6.3 ± 0.36 and shoots length: 6.5 ± 0.54 cm), in 4 weeks. Further, TDZ supplementation in the culture media efficiently activated the antioxidant system in the in vitro raised shoots, wherein maximum production of total phenolic content, TPC (34.33 ± 0.20 mg of GAE/g DW); total flavonoid content, TFC (8.99 ± 0.02 mg of QE/g DW); DPPH free radical scavenging activity (92.7 ± 1.32%); phenylalanine ammonia-lyase activity, PAL (8.99 ± 0.02 U/g FW); and superoxide dismutase expression, SOD (3.62 ± 0.01 nM/min/mg FW) were observed in the shoot cultures raised in presence of TDZ: 0.5 mg/L + Kn: 0.5 mg/L. Nonetheless, considerable levels of pharmacologically active lignans such as secoisolariciresinol (SECO: 23.13–37.10 mg/g DW), secoisolariciresinol diglucoside (SDG: 3.32–3.86 mg/g DW) and anhydrosecoisolariciresinol diglucoside (ANHSECO: 5.15–7.94 mg/g DW) were accumulated in the regenerated shoots. This protocol can be scaled up for the commercial production of linseed to meet the market demands for lignans.

scholarly journals Influence of Conditioned Media on the Re-Differentiation Capacity of Human Chondrocytes in 3D Spheroid Cultures

2020 ◽  
Vol 9 (9) ◽  
pp. 2798
Author(s):  
Annett Klinder ◽  
Sophie Kussauer ◽  
Bettina Hiemer ◽  
Andreas Wree ◽  
Rainer Bader ◽  
...  
Keyword(s):  
Conditioned Medium ◽  
Culture Media ◽  
Ex Vivo ◽  
Cartilage Matrix ◽  
Human Chondrocytes ◽  
Growth Media ◽  
Cell Cultivation ◽  
Cell Based Therapy ◽  
Tgf Β1

A major challenge of cell-based therapy for cartilage lesions is the preservation of the chondrogenic phenotype during ex vivo cell cultivation. In this in vitro study, the chondro-inductive capacity of two different hyaline cartilage-conditioned cell culture media on human chondrocytes in 3D spheroids was determined. Media were conditioned by incubation of 200 mg/mL vital or devitalized cartilage matrix in growth media over 35 days. The media were analyzed for the content of soluble procollagen type (Col) II and glycosaminoglycans (GAGs) as well as released TGF-β1, IGF-1 and IGFBP3. Unconditioned medium served as a negative control while the positive medium control was supplemented with TGF-β1 and IGF-1. Spheroid cultures prepared from human chondrocytes were cultivated at 37 °C, 5% CO2 and 21% O2 in the respective media and controls. After 14 and 35 days, the deposition of ECM components was evaluated by histological analysis. Vital cartilage-conditioned medium contained significantly higher levels of Col II and active TGF-β1 compared to medium conditioned with the devitalized cartilage matrix. Despite these differences, the incubation with vital as well as devitalized cartilage conditioned medium led to similar results in terms of deposition of proteoglycans and collagen type II, which was used as an indicator of re-differentiation of human chondrocytes in spheroid cultures. However, high density 3D cell cultivation showed a positive influence on re-differentiation.

The role of chitinases and glucanases in somatic embryogenesis of black pine and hybrid firs

2013 ◽  
Vol 8 (12) ◽  
pp. 1172-1182 ◽  
Author(s):  
Lenka Fráterová ◽  
Terézia Salaj ◽  
Ildikó Matušíková ◽  
Ján Salaj
Keyword(s):  
Somatic Embryogenesis ◽  
Culture Media ◽  
Extracellular Fluid ◽  
Abies Alba ◽  
Pinus Nigra ◽  
Callus Cultures ◽  
Growth Media ◽  
Large Variability ◽  
Embryogenic Cell ◽  
Embryogenic Potential

AbstractGlucanase and chitinase enzymes play an important role in different plant processes including defense against pathogens and morphogenesis. Moreover, their role in the processes of somatic embryogenesis has been demonstrated. It has been suggested, that the presence of this type of proteins might be a marker for embryogenic potential of callus cultures. In this work we screened for the presence of glucanases and chitinases in liquid growth media of a set of conifer embryogenic cell lines in order to find correlation with their embryogenic potential. We have found that none of the 12 chitinase isoforms detected in culture media of Pinus nigra Arn. or the nine chitinases detected in media with Abies alba × A. cephalonica and Abies alba × A. numidica embryogenic tissues could be linked to their embryogenic capacity. Similarly, none of the six glucanase isoforms detected in the extracellular fluid of Pinus nigra Arn. cultures can be assigned as a marker of embryogenic potential. Thus, our data indicate the large variability and doubtless importance of glucanases and chitinases for cell growth and development of somatic embryos, however, do not support the premise that they are markers of embryogenesis.

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