Multiple-variant design for the enrichment of photosynthetic bacterial populations

A design for the simultaneous variation of acetate, sulfide, and sulfate concentrations in 11 related media is described. Selectivity of these media by a direct enumeration technique in solid culture was compared with that for enrichment in liquid culture. Variation of nutritional parameters resulted in the selection of Rhodospirillaceae at initial enrichment concentrations of 0.1 g or less of Na2S∙9 H2O per litre and Chromatiaceae at 0.1 to 1.0 g of Na2S∙9 H2O per litre. The survival of sulfate-reducing and coliform bacteria indicated interdependency of photosynthetic populations with the former and competition with the latter. Photosynthetic bacteria selectively cultivated in liquid enrichment were tentatively identified as Rhodopseudomonas capsulata, Rhodopseudomonas spheroides, Chromatium warmingii, Chromatium okenii, Thiospirillum, and Rhabdomonas.

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THE USE OF SPECTROPHOTOMETRY IN AN ECOLOGICAL INVESTIGATION OF THE FACULTATIVELY ANAEROBIC PURPLE PHOTOSYNTHETIC BACTERIA

Canadian Journal of Microbiology ◽

10.1139/m67-173 ◽

1967 ◽

Vol 13 (9) ◽

pp. 1283-1293 ◽

Cited By ~ 11

Author(s):

Edward F. Haskins ◽

Toru Kihara

Keyword(s):

Photosynthetic Bacteria ◽

Rhodospirillum Rubrum ◽

Rhodopseudomonas Palustris ◽

Rhodopseudomonas Capsulata ◽

Purple Photosynthetic Bacteria ◽

Ecological Investigation ◽

Facultatively Anaerobic ◽

Isolation Techniques ◽

Spectral Evidence ◽

Rhodopseudomonas Spheroides

Diverse habitats were surveyed for the presence of Athiorhodaceae, using isolation techniques that permitted the development of only the facultatively anaerobic species of this family: Rhodopseudomonas capsulata, Rhodopseudomonas gelatinosa, Rhodopseudomonas palustris, Rhodopseudomonas spheroides, and Rhodospirillum rubrum. Of the 150 samples of soil, mud, sand, and water inoculated into enrichment media, 125 initiated cultures of photosynthetic bacteria, as indicated by spectrophotometric examination of the cultures. Subsequently, eight of these cultures were intensively investigated and isolates of the four species of Rhodopseudomonas were identified. Attempts to isolate Rhodospirillum rubrum from the cultures were unsuccessful. Species identifications were based on spectral examinations of aqueous cell-free preparations of the photosynthetic bacterial pigments. The species determinations based on the spectral evidence agreed with those based on the morphological and physiological criteria currently used for the identification of the Athiorhodaceae.

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Efficacy of the fungi Hirsutella minnesotensis and H. rhossiliensis from liquid culture for control of the soybean cyst nematode Heterodera glycines

Nematology ◽

10.1163/1568541054192153 ◽

2005 ◽

Vol 7 (1) ◽

pp. 149-157 ◽

Cited By ~ 22

Author(s):

Shufen Liu ◽

Senyu Chen

Keyword(s):

Heat Treatment ◽

Population Density ◽

Soybean Cyst Nematode ◽

Liquid Culture ◽

Heterodera Glycines ◽

Nematode Population ◽

Solid Culture ◽

Nematode Population Density ◽

Biological Control Potential ◽

Shoot Weight

AbstractHirsutella minnesotensis and H. rhossiliensis are endoparasites of nematodes, and their biological control potential against Heterodera glycines when cultured and applied on corn grits has been reported. In this study, the potential of liquid cultures of the two fungi was evaluated in two glasshouse experiments. Both liquid culture at 0.2, 0.4 and 0.8 g of fresh mycelium/300 cm3 soil (per pot) and solid culture at 1% (corn grits: soil, w/w) reduced nematode egg population densities in both autoclaved and unheated soils as compared with soil-only control or corn-grits control. However, the liquid culture at 0.2–0.8 g of mycelium/pot appeared to be more effective in reducing the nematode population than the solid culture of 1%. Hirsutella rhossiliensis resulted in lower nematode population density than H. minnesotensis only in unheated soil in one experiment. The soil heat treatment generally increased the nematode population density but did not affect percentage reduction of the nematode population density as compared with respective controls, except that reduction by H. rhossiliensis was greater in unheated soil than heat-treated soil in one experiment. Percentage of second-stage juveniles (J2) parasitised by fungi at the end of the experiment (60 days after planting) was generally higher with H. minnesotensis than with H. rhossiliensis. The percentage parasitism was positively correlated with initial fungal inoculation level. The soil heat treatment increased fungal parasitism in one experiment but not in the other. Plant growth was unaffected by treatments except that the soil heat treatment increased plant shoot weight as compared with unheated soil in one experiment.

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Selection of Potential Probiotic Lactobacillus with Inhibitory Activity Against Salmonella and Fecal Coliform Bacteria

Probiotics and Antimicrobial Proteins ◽

10.1007/s12602-017-9304-8 ◽

2017 ◽

Vol 10 (2) ◽

pp. 218-227 ◽

Cited By ~ 11

Author(s):

Mattika Abhisingha ◽

Jureeporn Dumnil ◽

Chetsadaporn Pitaksutheepong

Keyword(s):

Inhibitory Activity ◽

Fecal Coliform ◽

Coliform Bacteria ◽

Fecal Coliform Bacteria ◽

Probiotic Lactobacillus ◽

Selection Of

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A Novel Approach in Crude Enzyme Laccase Production and Application in Emerging Contaminant Bioremediation

Processes ◽

10.3390/pr8060648 ◽

2020 ◽

Vol 8 (6) ◽

pp. 648

Author(s):

Luong N. Nguyen ◽

Minh T. Vu ◽

Md Abu Hasan Johir ◽

Nirenkumar Pathak ◽

Jakub Zdarta ◽

...

Keyword(s):

Steroid Hormones ◽

Liquid Culture ◽

Emerging Contaminants ◽

White Rot Fungi ◽

Enzyme Concentration ◽

Crude Enzyme ◽

White Rot ◽

Laccase Production ◽

Solid Culture ◽

Novel Approach

Laccase enzyme from white-rot fungi is a potential biocatalyst for the oxidation of emerging contaminants (ECs), such as pesticides, pharmaceuticals and steroid hormones. This study aims to develop a three-step platform to treat ECs: (i) enzyme production, (ii) enzyme concentration and (iii) enzyme application. In the first step, solid culture and liquid culture were compared. The solid culture produced significantly more laccase than the liquid culture (447 vs. 74 µM/min after eight days), demonstrating that white rot fungi thrived on a solid medium. In the second step, the enzyme was concentrated 6.6 times using an ultrafiltration (UF) process, resulting in laccase activity of 2980 µM/min. No enzymatic loss due to filtration and membrane adsorption was observed, suggesting the feasibility of the UF membrane for enzyme concentration. In the third step, concentrated crude enzyme was applied in an enzymatic membrane reactor (EMR) to remove a diverse set of ECs (31 compounds in six groups). The EMR effectively removed of steroid hormones, phytoestrogen, ultraviolet (UV) filters and industrial chemical (above 90%). However, it had low removal of pesticides and pharmaceuticals.

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Influence of the origin of the inoculum on the anaerobic biodegradability test

Water Science & Technology ◽

10.2166/wst.2004.0017 ◽

2004 ◽

Vol 49 (1) ◽

pp. 53-59 ◽

Cited By ~ 15

Author(s):

I. Moreno-Andrade ◽

G. Buitrón

Keyword(s):

Most Probable Number ◽

Microbial Composition ◽

Probable Number ◽

Methanogenic Activity ◽

Sulfate Reducing ◽

Anaerobic Biodegradability ◽

Specific Methanogenic Activity ◽

Solids Content ◽

Different Sources ◽

Selection Of

Five different sources of inocula were studied to determine its influence on biodegradability tests. Inocula were characterized determining granulometry, specific methanogenic activity, solids content, and volumetric sludge index. Also, the fermentative, aceticlastic, hydrogenophilic, OPHA, and sulfate-reducing groups were determined by the most probable number technique. Anaerobic biodegradability tests were conducted with two different substrates, one easy to degrade (glucose) and a toxic one (phenol). The best performance, in terms of percent of biodegradation and lag time, for both substrates, was obtained with the inoculum from a brewery industry UASB. The results can be explained in terms of the initial activity of the inoculum. The influence of the significant variations found in the specific methanogenic activity of the five inocula studied is discussed, in terms of the microbial composition of the samples. The results emphasized the importance of the selection of an appropriate source of inoculum in order to obtain reliable results.

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Energy transduction in photosynthetic bacteria VI. Respiratory sites of energy conservation in membranes from dark-grown cells of Rhodopseudomonas capsulata

Biochimica et Biophysica Acta (BBA) - Bioenergetics ◽

10.1016/0005-2728(73)90114-x ◽

1973 ◽

Vol 314 (3) ◽

pp. 298-311 ◽

Cited By ~ 50

Author(s):

A.Baccarini Melandri ◽

D. Zannoni ◽

B.A. Melandri

Keyword(s):

Energy Conservation ◽

Photosynthetic Bacteria ◽

Energy Transduction ◽

Rhodopseudomonas Capsulata

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Changes in the acyl lipid composition of photosynthetic bacteria grown under photosynthetic and non-photosynthetic conditions

Biochemical Journal ◽

10.1042/bj1810339 ◽

1979 ◽

Vol 181 (2) ◽

pp. 339-345 ◽

Cited By ~ 39

Author(s):

Nicholas J. Russell ◽

John L. Harwood

Keyword(s):

Fatty Acids ◽

Photosynthetic Bacteria ◽

Rhodospirillum Rubrum ◽

Relative Proportion ◽

Photosynthetic Apparatus ◽

Growth Conditions ◽

Rhodopseudomonas Capsulata ◽

Rhodopseudomonas Sphaeroides ◽

Acyl Lipids ◽

And Function

The acyl lipids and their constituent fatty acids were studied in the photosynthetic bacteria Rhodospirillum rubrum, Rhodopseudomonas capsulata and Rhodopseudomonas sphaeroides, which were grown under photosynthetic and non-photosynthetic conditions. The major lipids were found to be phosphatidylethanolamine, phosphatidylglycerol and cardiolipin in each bacterium. The two Rhodopseudomonas species also contained significant quantities of phosphatidylcholine. Other acyl lipids accounted for less than 10% of the total. On changing growth conditions from non-photosynthetic to photosynthetic a large increase in the relative proportion of phosphatidylglycerol was seen at the expense of phosphatidyl-ethanolamine. In Rhodospirillum rubrum the fatty acids of the major phospholipids showed an increase in the proportion of palmitate and stearate and a decrease in palmitoleate and vaccenate on changing growth conditions to photosynthetic. In contrast, the exceptionally high levels (>80%) of vaccenate in individual phospholipids of Rhodopseudomonas capsulata and Rhodopseudomonas sphaeroides were unaffected by changing growth conditions to photosynthetic. Analysis of the lipids of chromatophores, isolated from the three bacteria, showed that these preparations were enriched in phosphatidylglycerol. The large increase in this phospholipid, seen during growth under photosynthetic conditions, appeared, therefore, to be due to a proliferation of chromatophore membranes. Possible roles for acyl lipids in the formation and function of the photosynthetic apparatus of bacteria are discussed.

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