scholarly journals Enhanced Removal of a Pesticides Mixture by Single Cultures and Consortia of Free and ImmobilizedStreptomycesStrains

2013 ◽  
Vol 2013 ◽  
pp. 1-9 ◽  
Author(s):  
María S. Fuentes ◽  
Gabriela E. Briceño ◽  
Juliana M. Saez ◽  
Claudia S. Benimeli ◽  
María C. Diez ◽  
...  
Keyword(s):  
Mixed Culture ◽  
Pure Culture ◽  
Immobilized Cells ◽  
Mixed Cultures ◽  
Ex Situ ◽  
Antagonistic Effects ◽  
Pure Cultures

Pesticides are normally used to control specific pests and to increase the productivity in crops; as a result, soils are contaminated with mixtures of pesticides. In this work, the ability ofStreptomycesstrains (either as pure or mixed cultures) to remove pentachlorophenol and chlorpyrifos was studied. The antagonism among the strains and their tolerance to the toxic mixture was evaluated. Results revealed that the strains did not have any antagonistic effects and showed tolerance against the pesticides mixture. In fact, the growth of mixed cultures was significantly higher than in pure cultures. Moreover, a pure culture (Streptomycessp. A5) and a quadruple culture had the highest pentachlorophenol removal percentages (10.6% and 10.1%, resp.), whileStreptomycessp. M7 presented the best chlorpyrifos removal (99.2%). Mixed culture of allStreptomycesspp. when assayed either as free or immobilized cells showed chlorpyrifos removal percentages of 40.17% and 71.05%, respectively, and for pentachlorophenol 5.24% and 14.72%, respectively, suggesting better removal of both pesticides by using immobilized cells. These results reveal that environments contaminated with mixtures of xenobiotics could be successfully cleaned up by using either free or immobilized cultures ofStreptomyces, throughin situorex situremediation techniques.

Impact of Transfaunation of Rumen Ciliate Cultures on Physical Examination, Selected Serum Parameters and Milk Profile in Defaunated Lactating Dairy Goats

2020 ◽  
Keyword(s):  
Physical Examination ◽  
Mixed Culture ◽  
Pure Culture ◽  
Milk Fat ◽  
Mixed Cultures ◽  
Dairy Goats ◽  
Serum Parameters ◽  
Native Breed ◽  
Culture Duration ◽  
Inorganic Phosphorous

Rumen ciliates still have mysterious secrets and influences in ruminants. This study investigated the effect of transfaunation of pure and mixed cultures of rumen ciliates on physical clinical examination, selected serum parameters and milk profile in defaunated lactating dairy goats. A number of 8 Baladi native breed goats were randomly classified into two groups each one containing 4 goats. Pure culture group was transfaunated with 6 ml of pure culture of Holotricha spp., while mixed culture group was transfaunated with 6 ml of mixed culture of 81.85% Holotricha and 18.15% Ophryoscolex spp. once weekly for three consecutive weeks, after defaunation of both groups using 30 ml of 8% SLS for two consecutive days. Serum and milk samples were collected weekly for three successive weeks to study effect of type of ciliate culture, duration of transfaunation and their interaction. Results revealed that transfaunation of pure and mixed cultures of rumen ciliates had no effect on physical examination with minimal non-significant improvement of calcium, inorganic phosphorous, total protein and globulin in serum of defaunated goats. Transfaunation of pure or mixed cultures of rumen ciliates within three weeks could not improve significantly decreased milk fat % of defaunated goats without any effect on other measured milk profile parameters. It is concluded that further investigations on transfaunation without prior defaunation should be performed using different pure and mixed cultures of rumen ciliates for therapeutic and productive purposes.

Studies in intermicrobial symbiosis. Saccharomyces cerevisiae and Lactobacillus casei

1972 ◽  
Vol 18 (11) ◽  
pp. 1733-1742 ◽  
Author(s):  
R. D. Megee III ◽  
J. F. Drake ◽  
A. G. Fredrickson ◽  
H. M. Tsuchiya
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Continuous Culture ◽  
Mixed Culture ◽  
Growth Medium ◽  
Lactobacillus Casei ◽  
Mixed Cultures ◽  
Genetic Characteristics ◽  
Culture Techniques ◽  
Pure Cultures

Saccharomyces cerevisiae and a riboflavin assay strain of Lactobacillus casei have been propagated anaerobically in mixed culture. Both batch and continuous culture techniques were used. By varying the concentrations of glucose and riboflavin in the growth medium, it was possible to produce symbioses of commensalism + competition, competition, and mutualism + competition. In short, the interaction prevailing is determined by the medium as well as by the genetic characteristics of the organisms. The behavior of the mixed cultures in these situations was predicted from data taken on pure cultures of the organisms.

Interaction profile of a mixed-culture fermentation of Issatchenkia orientalis and Saccharomyces cerevisiae by transcriptome sequencing

2020 ◽  
Vol ahead-of-print (ahead-of-print) ◽  
Author(s):  
Wenwen Zhang ◽  
Peifang Weng ◽  
Zufang Wu
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Mixed Culture ◽  
Mixed Cultures ◽  
Expression Level ◽  
Adaptive Responses ◽  
Mixed Fermentation ◽  
Mixed Culture Fermentation ◽  
Content Type ◽  
Issatchenkia Orientalis ◽  
Pure Cultures

PurposeMixed fermentation with Saccharomyces cerevisiae and non-Saccharomyces yeasts has become an oenlogical tool to improve wines’ organoleptic properties. However, the maximum utilization of this method is dependent upon understanding the influence of mixed cultures on the physiology of S.cerevisiae and non-Saccharomyces yeasts.Design/methodology/approachIn this study, the supernatants from 48 h mixed-culture fermentation were added to the pure cultures of Issatchenkia orientalis and Saccharomyces, respectively. And the authors used RNA sequencing to determine the transcriptome change of I.orientalis and S.cerevisiae in a mixed culture.FindingsThe results showed that multiple genes associated with cell growth and death were differentially expressed. Genes related to biosynthesis of amino acids were enriched among those upregulated in the mixed-fermentation supernatant. Meanwhile, the differential expression level of genes encoding enzymes essential for formation of aroma compounds was found in the single and in the mixed fermentation. The high expression level of molecular chaperones Hsp70, Hsp90 and Hsp110 suggests that metabolites of mixed-culture fermentation may lead to aggregation of misfolded proteins. Moreover, upregulation of ethanol dehydrogenase I ADH1 in the mixed-culture fermentations was highlighted.Originality/valueThis is the first time that RNA-seq was used to analyze changes in the transcriptome of mixed cultures. According to the results the authors’ manuscript provided, an integrated view into the adaptive responses of S.cerevisiae and non-Saccharomyces yeasts to the mixed-culture fermentation is benefit for the potential application of S.cerevisiae and non-Saccharomyces yeasts in fruit wine brewing.

Increased in vitro sensitivity of Candida albicans to amphotericin B when grown in mixed culture with Escherichia coli

1978 ◽  
Vol 24 (12) ◽  
pp. 1482-1489 ◽  
Author(s):  
L. G. Mathieu ◽  
D. Dube ◽  
M. Lebrun
Keyword(s):  
Escherichia Coli ◽  
Candida Albicans ◽  
Amphotericin B ◽  
Mixed Culture ◽  
Mixed Cultures ◽  
Polyene Antibiotics ◽  
E Coli ◽  
Pure Cultures

The growth of Candida albicans was inhibited by some Escherichia coli strains both in conventional batch cultures and also in a chemostat under conditions of constant addition of fresh medium. Concentrations of 0.2 μg amphotericin B per millilitre and of 2 μg nystatin per millilitre, which caused a slight inhibition of C. albicans in pure culture, exerted a strong fungicidal effect when the yeast was placed in mixed cultures with certain strains of E. coli. Candida albicans cells, inhibited by either E. coli or in mixed culture with polyene antibiotics, appeared larger and less uniformly stained by acridine orange than control cells from pure cultures. Addition of chloramphenicol to the mixed cultures, in quantities sufficient to kill the E. coli cells, abolished the increased sensitivity of C. albicans to amphotericin B or nystatin. In preliminary in vivo tests, E. coli did not sensitize C. albicans to the polyene antibiotics.

scholarly journals Potential Role of Thiobacillus caldus in Arsenopyrite Bioleaching

1999 ◽  
Vol 65 (1) ◽  
pp. 36-40 ◽  
Author(s):  
Mark Dopson ◽  
E. Börje Lindström
Keyword(s):  
Mixed Culture ◽  
Pure Culture ◽  
Potential Role ◽  
Mixotrophic Growth ◽  
Moderately Thermophilic ◽  
Surface Active Agents ◽  
Pure Cultures ◽  
Surface Active ◽  
Leaching Efficiency

ABSTRACT We investigated the potential role of the three strains ofThiobacillus caldus (KU, BC13, and C-SH12) in arsenopyrite leaching in combination with a moderately thermophilic iron oxidizer,Sulfobacillus thermosulfidooxidans. Pure cultures ofT. caldus and S. thermosulfidooxidans were used as well as defined mixed cultures. By measuring released iron, tetrathionate, and sulfur concentrations, we found that the presence ofT. caldus KU and BC13 in the defined mixed culture lowered the concentration of sulfur, and levels of tetrathionate were comparable to or lower than those in the presence of S. thermosulfidooxidans. This suggests that T. caldusgrows on the sulfur compounds that build up during leaching, increasing the arsenopyrite-leaching efficiency. This result was similar to leaching arsenopyrite with a pure culture of S. thermosulfidooxidans in the presence of yeast extract. Therefore, three possible roles of T. caldus in the leaching environment can be hypothesized: to remove the buildup of solid sulfur that can cause an inhibitory layer on the surface of the mineral, to aid heterotrophic and mixotrophic growth by the release of organic chemicals, and to solubilize solid sulfur by the production of surface-active agents. The results showed that T. caldus KU was the most efficient at leaching arsenopyrite under the conditions tested, followed by BC13, and finally C-SH12.

scholarly journals Physiological and biochemical evaluation of pure cultures of problematic filamentous bacteria isolated from activated sludge

2004 ◽  
Author(s):  
◽  
Tshireletso R. Ramothokang
Keyword(s):  
Wastewater Treatment ◽  
Activated Sludge ◽  
Pure Culture ◽  
Morphological Traits ◽  
Filamentous Bacteria ◽  
Storage Compounds ◽  
Pure Cultures ◽  
Physiological And Biochemical

Since the development of the activated sludge process, bulking and foaming have been a major problem affecting treatment efficiency. Filamentous bacteria have long been known to be the primary cause of bulking and foaming problems in activated sludge wastewater treatment systems. Attempts to cure filamentous bulking and foaming have thus far not shown great success in effective long-term control measures due to a lack of understanding of these organisms. Chemical methods such as chlorination and the use of hydrogen peroxide are still used to cure bulking but are only effective as interim measures. This could be due to the main factors stimulating filamentous bacterial growth not being changed by these methods for curing bulking and also, a lack of in-depth understanding of filamentous bacteria by scientists. It is therefore important to gain a proper understanding of these bacteria on the basis of their physiological, biochemical and growth characteristics. For all this to be successfully attained, filamentous bacteria need to be studied in pure culture so as to facilitate a better understanding of bulking and foaming and the control thereof during wastewater treatment. The aim of this study was therefore, to isolate and cultivate problematic filamentous bacteria and determine the physiological, biochemical and morphological traits of these organisms in pure culture, with the purpose of being able to integrate these findings to in situ analysis. Using four different isolation techniques, a total of 14 isolates from 7 different wastewater systems were obtained and evaluated for a range of physical, chemical, redox and substrate conditions. Results of the study indicate that filamentous survival and proliferation in BNR systems is largely due to varied phosphate uptake capacities and widespread ability to denitrify both nitrate and nitrite. Lipid hydrolysis is also a major component of filamentous bacterial metabolism with hydrolysis of other large compounds, as revealed by Biolog, such as starch, dextrin, proteins/peptides, Tween 40, Tween 80 and nucleosides indicating an affinity for larger slowly biodegradable substrates. They also strive on a variety of amino acids and sugars. The results obtained in this study revealed that filamentous bacteria are more diverse and complex in their biochemistry and physiology hence the difficulty in achieving long- term optimal control of filamentous bulking in activated sludge. It was concluded that filamentous bacteria have the ability to survive during times of starvation where growth factors are limiting and, this may be attributed to their ability to store storage compounds such as PHB, glycogen and polyP. The filaments' ability to store storage compounds and denitrify, suggests that they may in fact play significant roles in denitrification and EBPR. It is also concluded from this study that the filamentous bacteria under study are sensitive to aromatic compounds and that they have an affinity for slowly biodegradable polymers such as lipids, nucleosides, proteins/ peptides, dextrin and starch. Also concluded is that, the use of Biolog for biochemical profiling! fingerprinting of filamentous bacteria is useful, however, due to the possibility that some organisms may in fact, not grow and! or may give negative results on some and! or all substrates, other strategies. for biochemical profiling be established and used in this regard. Identification and evaluation of filamentous bacteria based on morphological traits is limiting and requires development and optimization of in situ techniques, such as DNAIRNA based probes and micro autoradiography. Bulking and BNR are elaborate and still not fully understood. The filaments' ability to take up phosphates and denitrify means that an advanced understanding of the roles they play in BNR systems and AA- bulking (Anoxic- Aerobic) is still required. Physiological and biochemical fingerprinting of pure cultures of filamentous bacteria is an important basis to understanding these organisms, and establishing potential bulking and foaming criteria for in situ evaluation and verification. It is from a study such as this that the main goal of curing bulking and gaining an enhanced understanding of BNR may be achieved.

scholarly journals Technical sheet of influence of Freeze-Dried Yeast Starter Cultures on Volatile Compounds of Tchapalo, a Traditional Sorghum Beer from Côte d’Ivoire

2017 ◽  
Vol 6 (3) ◽  
pp. 913-918
Author(s):  
COULIBALY Wahauwouélé Hermann ◽  
BOUATENIN Koffi Maizan Jean-Paul ◽  
KOUAME Kohi Alfred ◽  
RIGOU Peggy
Keyword(s):  
Volatile Compounds ◽  
Mixed Culture ◽  
Pure Culture ◽  
Empirical Process ◽  
Starter Cultures ◽  
Higher Alcohols ◽  
Higher Alcohol ◽  
Freeze Dried ◽  
Pure Cultures ◽  
Microbiological Stability

The production of the Ivorian sorghum beer known as tchapalo remains more or less an empirical process. The use of starter cultures was therefore suggested as the appropriate approach to alleviate the problems of variations inorganoleptic quality and microbiological stability. In this study, we evaluated the capacity of S. cerevisiae and C. tropicalis to produce sorghum beer as freeze-dried starter in mixed or pure cultures. Beers produced with mixed freeze-dried cultures of S. cerevisiae F12-7 and C. tropicalis C0-7 showed residual sugars and ethanol contents similar to beers obtained with S. cerevisiae F12-7 pure culture, but the total sum of organic acids analyzed was the highest with the mixed culture (15.71 g/L). Higher alcohols were quantitatively the largest group of volatile compounds detected in beers. Among these compounds, 2-phenyl ethanol, a higher alcohol that plays an important role in beer flavor, was highly produced with the mixed culture (10174.8 µg/L) than with the pure culture (8749.9 µg/L).

Plaque Formation by Mixed Cultures of Nonprimary Plaque-Forming Microorganisms

1974 ◽  
Vol 53 (4) ◽  
pp. 825-831 ◽  
Author(s):  
John C. Parsons ◽  
Chris H. Miller
Keyword(s):  
Mixed Culture ◽  
Pure Culture ◽  
Plaque Formation ◽  
Mixed Cultures ◽  
Streptococcus Salivarius

Some oral organisms that do not form artificial plaque in pure culture interacted to form adherent plaque when combined in mixed culture. The presence of a nonprimary plaque-forming strain of Streptococcus salivarius in combinations with one of several other nonprimary plaque formers, resulted in depositions of large quantities of plaque containing significant amounts of a fructose-positive polysaccharide.

scholarly journals Alamethicin Suppresses Methanogenesis and Promotes Acetogenesis in Bioelectrochemical Systems

2015 ◽  
Vol 81 (11) ◽  
pp. 3863-3868 ◽  
Author(s):  
Xiuping Zhu ◽  
Michael Siegert ◽  
Matthew D. Yates ◽  
Bruce E. Logan
Keyword(s):  
Mixed Culture ◽  
Organic Compounds ◽  
Average Rate ◽  
Mixed Cultures ◽  
Reduction Product ◽  
Bioelectrochemical Systems ◽  
Content Type ◽  
Microbial Electrosynthesis ◽  
Pure Cultures ◽  
Sporomusa Ovata

ABSTRACTMicrobial electrosynthesis (MES) systems with mixed cultures often generate a variety of gaseous and soluble chemicals. Methane is the primary end product in mixed-culture MES because it is the thermodynamically most favorable reduction product of CO2. Here, we show that the peptaibol alamethicin selectively suppressed the growth of methanogens in mixed-culture MES systems, resulting in a shift of the solution and cathode communities to an acetate-producing system dominated bySporomusa, a known acetogenic genus in MES systems.Archaeain the methane-producing control were dominated byMethanobrevibacterspecies, but noArchaeawere detected in the alamethicin-treated reactors. No methane was detected in the mixed-culture reactors treated with alamethicin over 10 cycles (∼3 days each). Instead, acetate was produced at an average rate of 115 nmol ml−1day−1, similar to the rate reported previously for pure cultures ofSporomusa ovataon biocathodes. Mixed-culture control reactors without alamethicin generated methane at nearly 100% coulombic recovery, and no acetate was detected. These results show that alamethicin is effective for the suppression of methanogen growth in MES systems and that its use enables the production of industrially relevant organic compounds by the inhibition of methanogenesis.

scholarly journals PRODUCTION OF PHYTOHORMONES OF BRADYRHIZOBIUM JAPONICUM AND AZOSPIRILLUM BRASILENSE UNDER THEIR SIMULTANEOUS CULTIVATION

2018 ◽  
Vol 28 ◽  
pp. 33-40
Author(s):  
S.F. Kozar
Keyword(s):  
Abscisic Acid ◽  
Mixed Culture ◽  
Pure Culture ◽  
Bradyrhizobium Japonicum ◽  
Azospirillum Brasilense ◽  
Culture Fluid ◽  
Culture Liquid ◽  
Nitrogen Fixing ◽  
Nitrogen Fixing Bacteria ◽  
Pure Cultures

Objective. Investigate the activity of biosynthesis of phytohormonal substances with nitrogen-fixing bacteria Bradyrhizobium japonicum and Azospirillum brasilense in pure and mixed culture. Methods. Microbiological, chromatographic, and mathematical. Results It has been established that the simultaneous cultivation of B. japonicum M-8 and A. brasilense 410 increases the content of gibberellins and cytokinins in the culture fluid of the test microorganisms. The content of gibberellic acid and isopentenylidene has increased most intensively in mixed culture compared with the pure culture of rhizobia. In the course of co-cultivation, the studied diazotrophs more intensively produced auxins compared to soybean rhizobia in pure culture, but less compared to pure culture of azospirilla. The highest level of abscisic acid that can inhibit the formation of nodules was found in A. brasilense 410 culture fluid, and it was lower when cultivating B japonicum M-8. However, the smallest amount of this phytohormone was found in the culture liquid of diazotrophs under their co-cultivation. The lowest ratio of auxin/cytokinin was found in B. japonicum M-8 and A. brasilense 410 culture fluid under their co-cultivation, which should positively influence the formation of a symbiotic system when interacting with soybean plants. Conclusion. A combination of cultivating rhizobia and azospirilla showed an increase in the amount of cytokinins and gibberellins in the culture fluid of the microorganisms, a decrease in the amount of abscisic acid and improvement in the auxin/cytokinin ratio compared to the values of the pure cultures of the nitrogen-fixing bacteria studied. An analysis of the quantitative parameters of the content of phytohormones suggests the feasibility of combining B. japonicum and A. brasilense in a mixed culture for the effective introduction of rhizobia in soybean agrocenosis.

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