bluuebunny/crossref_metadata_2025 huggingface dataset:
Nutritional and biochemical characterization of Methanospirillum hungatii
Authors: Ferry J G , Wolfe R S
Published: January 2020

To ascertain its physiological similarity to other methanogenic bacteria, Methanospirillum hungatii, the type species of the genus, was characterized nutritionally and biochemically. Good growth occurred in a medium consisting of mineral salts, cysteine sulfide reducing buffer, and an H2-CO2 (80:20) atmosphere. Addition of amino acids and B vitamins stimulated growth. Cell-free extracts contained methylcobalamin-coenzyme M methyltransferase, methylreductase, and formate hydrogenlyase. Cells contained coenzyme M and coenzyme F420. Coenzyme F420 was required for formate hydrogenlyase activity. Coenzyme F420 purified from M. hungatii had identical properties to that purified from species of Methanobacterium. The physiological basis of the family Methanobacteriaceae is strengthened by these findings.
Recovery of spores of Clostridium botulinum in yeast extract agar and pork infusion agar after heat treatment
Authors: Odlaug T E , Pflug I J
Published: January 2020

Yeast extract agar, pork infusion agar, and modifications of these media were used to recover heated Clostridium botulinum spores. The D- and z-values were determined. Two type A strains and one type B strain of C. botulinum were studied. In all cases the D-values were largest when the spores were recovered in yeast extract agar, compared to the D-values for spores recovered in pork infusion agar. The z-values for strains 62A and A16037 were largest when the spores were recovered in pork infusion agar. The addition of sodium bicarbonate and sodium thioglycolate to pork infusion agar resulted in D-values for C. botulinum 62A spores similar to those for the same spores recovered in yeast extract agar. The results suggest that sodium bicarbonate and sodium thioglycolate should be added to recovery media for heated C. botulinum spores to obtain maximum plate counts.
Animal fecal carriership and biotypes of Staphylococcus aureus
Authors: Dimitracopoulos G , Kalkani-Boussiakou H , Papavassiliou J
Published: January 2020

Staphylococcus aureus was found in 44% of the rectal swabs from 377 pigs and in 12% of the swabs from 147 cows. Seventy-one percent of the isolates from pigs showed fibrinolytic activity and grew in colonies of the negative violet type on crystal violet agar. In this group, 47% of the isolates coagulated both human and bovine plasmas and were characterized as intermediate type, whereas 24% coagulated human plasma and were classified as human biotype A. Among the fibrinolysin-negative isolates, 15, 12, and 2% were identifiable as animal biotypes B, C, and E, respectively. The cow isolates were classified as intermediate type (51%), human biotype A (40%), and animal biotype C (9%).
Degradation of the plant flavonoid phellamurin by Aspergillus niger
Authors: Sakai S
Published: January 2020

We have previously described the structure of phellamurin, a plant flavonoid, as 3,4',5,7-tetrahydroxy-8-isoprenylflavanone-7-O-glucoside (17). Degradation of phellamurin by Aspergillus niger using modified Czapek-Dox medium as well as phellamurin or one of its degradation products as a sole carbon source, is reported here. Eleven compounds are identified from phellamurin degradation products. A. niger apparently decomposes phellamurin by first removing glucose with beta-glucosidase; neophellamuretin is the first degradation product. Fission of the heterocyclic ring of (5''-hydroxyisopropyl-4'',5''-dihydrofurano)[2'',3''-h]3,4',5-trihydroxyflavanone, which is obtained from neophellamuretin through a few alterations of the side chain, is followed by cleavage of a C--C bond between C=O and carbon at alpha-position and conversion of (5''-hydroxyisopropyl-4'',5''-dihydrofurano)[2'',3''-d]-2',4,6',alpha-tetrahydroxychalcone to rho-hydroxymandelic acid (B-ring) and 2,4,6-trihydroxy-5-carboxyphenylacetic acid (A-ring). It is suggested that rho-hydroxymandelic acid is oxidized to rho-hydroxybenzoic acid. 2,4,6-Trihydroxy-5-carboxyphenylacetic acid is metabolized to phloroglucinol carboxylic acid, which subsequently is decarboxylated to phloroglucinol. These results provided new information on the isoprene unit metabolism of the side chain of phellamurin and firmly established the degradation pathway of phellamurin by A. niger.
Determination of pools of tricarboxylic acid cycle and related acids in bacteria
Authors: Siegel W H , Donohue T , Bernlohr R W
Published: January 2020

Methods for sampling, extracting, and quantitating the metabolic pools of organic acids from bacteria have been developed. The concentration of these metabolites was determined by a new gas chromatographic method that can quantitatively determine the levels of lactate, pyruvate, fumarate, succinate, malate, alpha-ketoglutarate, and citrate. Values obtained were confirmed by fluorimetric analyses of five of the individual acids. In Escherichia coli, pools range from about 1 to 5 mumol/g of dry weight, with a variation in replicate samples of 5 to 15%. Under similar conditions, these pools in Bacillus licheniformis are in the same range, although the pyruvic acid pool is significantly larger.
Salmonellae in health foods
Authors: Thomason B M , Cherry W B , Dodd D J
Published: January 2020

Various health food products of different brands were purchased from stores in the metropolitan Atlanta area. These foods were examined for the presence of salmonellae by fluorescent-antibody and cultural methods. Included in the study were tablets of alfalfa, parsley, kelp, wheat bran, enzyme, bone meal, and vitamins. Beef liver powder and tablets and granola cereal were also studied. Salmonella minnesota, Salmonella anatum, and Salmonella derby were isolated from two of three lots of beef liver powder from one manufacturer. All other products were negative.
Dialysis Continuous Process for Ammonium-Lactate Fermentation of Whey: Mathematical Model and Computer Simulation
Authors: Coulman G. A. , Stieber R. W. , Gerhardt Philipp
Published: January 2020

A mathematical model was developed to describe a dialysis process for the continuous fermentation of whey lactose to lactic acid, with neutralization to a constant pH by ammonia. In the process, whey of a relatively high concentration is fed into the fermentor circuit at a relatively low rate so that the residual concentration of lactose is low. The fermentor effluent contains ammonium lactate, bacterial cells, and residual whey solids and could be used as a nitrogen-enriched feedstuff for ruminant animals. Only water is fed into the dialysate circuit at a relatively high rate. The dialysate effluent contains purified ammonium lactate and could be converted to lactic acid and ammonium sulfate for industry. The fermentation was specifically modeled as a set of equations representing material balances and rate relationships in the two circuits. Dialysis continuous fermentations, in general, were modeled by combining these equations and by using dimensionless parameters. The generalized model was then solved for the steady state and used to simulate the specific fermentation on a digital computer. The results showed the effects of various material and operational and kinetic parameters on the process and predicted that it could be operated efficiently.
Isolation of Yersinia enterocolitica from well water and growth in distilled water
Authors: Highsmith A K , Feeley J C , Skaliy P , Wells J G , Wood B T
Published: January 2020

Yersinia enterocolitica was recovered from well water during a large water-borne outbreak of gastrointestinal illness. Isolates were predominantly Nilehn biotype 1, of which 57% were serologically nontypable. Isolation and enumeration of these Y. enterocolitica strains were made on M-Endo broth. Laboratory studies were conducted on selected isolates to establish the growth of Y. enterocolitica in distilled water and the competitive growth of this organism in various enteric media. Growth was obtained in sterile distilled water without added nutrients at 4, 25, and 37 degrees C. M-Endo medium gave equal or better recovery of Y. enterocolitica in competitive growth studies than did other commonly used enteric media using the membrane filter technique and incubating at 35 degrees C. All well water isolates were confirmed biochemically at 25 and 35 degrees C and serotyped, and antibiotic susceptibility tests were performed.
Occurrence of Aspergillus fumigatus during composting of sewage sludge
Authors: Millner P D , Marsh P B , Snowden R B , Parr J F
Published: January 2020

Aspergillus fumigatus, a medically important fungal opportunist and respiratory allergen, was isolated from woodchips and sewage sludge used in the production of compost at the U.S. Department of Agriculture's composting research facility in Beltsville, Md. It was also regularly isolated as a dominant fungus during forced aeration composting and after 30 days in an unaerated stationary curing pile; in both cases, the fungus was found in pile zones with temperatures less than 60 degrees C. Compost stored outdoors in stationary unaerated piles from 1 to 4 months after screening out of woodchips contained easily detectable amounts of A. fumigatus in the exterior pile zones (0- to 25-cm depths). Semiquantitative studies of the airspora at the composting site revealed that A. fumigatus constituted 75% of the total viable mycoflora captured. At locations 320 m to 8 km from the compost site, the fungus constituted only 2% of the total viable mycoflora in the air. Of 21 samples of commercially available potting soil, one had levels of A. fumigatus nearly equivalent to those of 1-month-old storage compost; 15 others had lower but detectable levels.
Double-stranded ribonucleic acid in viruses of Penicillium citrinum
Authors: Benigni R , Ignazzitto G , Volterra L
Published: January 2020

The nucleic acid content of two viral populations in a strain of Penicillium citrinum is shown to be double-stranded ribonucleic acid, resolved through polyacrylamide gel electrophoresis into 10 size groups ranging from 1.17 to 3.98 megadaltons.
Comparison of miniaturized multitest systems with conventional methodology for identification of Enterobacteriaceae from foods
Authors: Guthertz L S , Okoluk R L
Published: January 2020

Four miniaturized multiple test systems were compared with tube methodology used to identify Enterobacteriaceae encountered in foods. Identification aids supplied with each system were used to assign names to isolates at the species level. For the 129 strains tested, the Minitek system demonstrated a 96.9 percent agreement with reactions in tubed media. The Inolex, Analytab, and PathoTec test systems exhibited 94.3, 93.8, and 92.7 percent agreement, respectively. Analytab identified 96.1 percent of the isolates to the species level, whereas the Minitek, PathoTec, and Inolex systems were able to identify 78.3, 32.6, and 27.1 percent, respectively. The results indicate that the Analytab and Minitek systems are acceptable substitutes for the tube methodology routinely employed in identifying enterics from foods. Although the PathoTec system might be used to screen isolates for their identity, neither the presently available PathoTec nor the Inolex systems should be substituted for current methodology when definitive identification of foodborne organisms is required.
Microbial transformations of styrene and [14C] styrene in soil and enrichment cultures
Authors: Sielicki M , Focht D D , Martin J P
Published: January 2020

Two different mechanisms were responsible for the disappearance of styrene in enrichment cultures: (i) a mixed population of microorganisms, capable of utilizing styrene as a sole carbon source, oxidized this substrate to phenylethanol and phenylacetic acid; (ii) the culture also mediated polymerization of the monomer to low-molecular-weight styrene oligomers. This chemical reaction probably occurred as the result of microbial degradation of butylcatechol, an antioxidant polymerization inhibitor present in commercial styrene. The resultant polymer material was subsequently metabolized. In soil incubation studies, 14CO2 evolution from applied [8-14C] styrene was used to estimate microbial degradation. Approximately 90 percent of the labeled carbon was evolved from a 0.2 percent addition, and about 75 percent was lost from the 0.5 percent application over a 16-week period.
Large-scale production and concentration of infectious Epstein-Barr virus
Authors: Klein F , Rosensteel J F , Hummer R M , Hillman E A , Riggs C W , Charmella L J
Published: January 2020

Infectious Epstein-Barr virus (EBV) was produced from suspension cultures of P3HR-1 cells. A protocol for the scaled-up production and concentration of the virus was developed. Virus from the culture fluid was concentrated by continuous-flow pelletization or continuous flow with banding in sucrose. EBV prepared by pelletization yielded 1.7 X 10(4) infectious units/ml (100 X concentration) and less than 3.4 X 10(7) EVB particles/ml (1,000 X concentration), whereas EBV prepared by banding yielded 4.6 X 10(3) infectious units/ml (100 X concentration) aand 1.3 X 10(8) EBV particles 1 ml (1,000 X concentration). The majority of the virus particles observed were "empty" membrane-associated particles. A statistical test of the correlation between infectivity and virus particle count was made.
Dulcitol-malonate-phenylalanine agar for the identification of Salmonella and other Enterobacteriaceae
Authors: Eskenazi S , Littell A M
Published: January 2020

An agar medium combining dulcitol fermentation, malonate utilization, and phenylalanine deamination was evaluated with 229 isolates representing 19 genera. All reactions agreed with those obtained on conventional media.
Role of heterotrophic nutrition in growth of the alga Scenedesmus obliquus in high-rate oxidation ponds
Authors: Abeliovich A , Weisman D
Published: January 2020

The green alga Scenedesmus obliquus readily adapted to heterotrophic growth in the dark, utilizing glucose as the sole carbon source. Heterotrophic cells differed significantly from photoautotrophic cells with respect to several physiological properties such as the rate of photoassimilation of CO2, rate of incorporation of glucose, and chlorophyll a concentration. Oxidation pond cells shared features common to both photoautotrophic and heterotrophic cells. Approximately 15 percent of oxidation pond algal carbon was derived from glucose assimilated directly without first being oxidized by bacteria. Bacteria seem to play a minor role in biological oxygen demand reduction in high-rate oxidation ponds, and their role is probably confined to degradation of biopolymers, thus producing substrates for algal consumption.
Enhancing nitrite inhibition of Clostridium botulinum with isoascorbate in perishable canned cured meat
Authors: Tompkin R B , Christiansen L N , Shaparis A B
Published: January 2020

Addition of sodium isoascorbate to the formulation for perishable canned comminuted cured meat markedly enhanced the efficacy of nitrite against Clostridium botulinum. This effect was reproducible through a series of three tests. In one test it was found that the initial addition of 50 microgram of sodium nitrite per g plus isoascorbate was as effective as 156 microgram of sodium nitrite per g alone.
Compact liquid nitrogen storage system yielding high recoveries of gram-negative anaerobes
Authors: Gilmour M N , Turner G , Berman R G , Krenzer A K
Published: January 2020

A simple and compact system suitable for the preservation of fragile gram negative anaerobes and other bacteria in liquid N2 has been developed. Polypropylene straws used as specimen containers can be used easily within glove bags of anaerobic chambers, and their small size greatly increases the number of cultures which can be stored. Ancillary equipment and methods developed are described. The overall system was tested, using Streptococcus mutans, Fusobacterium nucleatum, and Selenomonas sputigena. Various basal suspending fluids and cryoprotective supplements were studied. With fast rates of freezing and thawing, survival recoveries of the test microorganisms ranged from 80 to 100 percent of the input colony-forming units in a complex medium broth base without cryoprotective agent addition, and they consistently were 100 percent when 0.4 mM polyvinylpyrrolidine was used. Overall, cryoprotection by polyvinyl pyrrolidine was superior to that from glycerol or dimethyl sulfoxide, the latter yielding recoveries similar to or less than those obtained with no cryoprotectant additive. All microorganisms were recoverable after storage for 1 year.
Studies on the differential inhibition by azide on the nitrite/nitrous oxide level of denitrification
Authors: Sidransky E , Walter B , Hollocher T C
Published: January 2020

A gas chromatographic method was used to demonstrate that nitrite can counteract the inhibition by azide of nitrous oxide reductase activity in denitrifiers. This effect explains why azide (and cyanide) can inhibit nitrogen production from nitrous oxide in these organisms but have little effect on nitrogen production from nitrite. Although the physiological basis by which nitrite opposes the action of azide remains unknown, extensive destruction of azide by nitrite can be ruled out as an explanation.
Isolation and properties of fecal proteins and fecal alkaline phosphatase from germfree and conventional rats
Authors: Nakano M , Sumi Y , Miyakawa M
Published: January 2020

Fecal proteins from germfree and conventional rats were isolated. The proteins from the two kinds of feces differed in molecular weight, judging from Sephadex gel filtration and sodium dodecyl sulfate-polyacrylamide gel electrophoresis. The conventional feces contained a greater amount of high-molecular-weight and a lesser amount of low-molecular-weight proteins than did the germfree feces. The fecal proteins of both kinds contained carbohydrates. Both feces contained considerable enzyme activity. The germfree feces contained extremely high activity in alkaline phosphatase and leucine aminopeptidase. Both feces showed the same level of trehalase activity. The conventional feces contained higher levels of activity of protease and acid phosphatase than did the germfree feces. Lactase activity was observed only in the conventional feces. The fecal alkaline phosphatase resembled the intestinal enzyme in response to L-phenylalanine inhibition and urea denaturation. From these results it was inferred that the germfree feces contained some of the intestinal proteins and that the conventional feces contained bacterial proteins in addition to intestinal proteins.
Airborne enteric bacteria and viruses from spray irrigation with wastewater
Authors: Teltsch B , Katzenelson E
Published: January 2020

The relationship between bacterial concentrations in wastewater used for spray irrigation and in the air was examined. Aerosolized coliforms were detected when their concentration was 10(3)/ml or more in the wastewater. Relative humidity and solar irradiation appeared to affect viable bacteria in the air; a positive correlation was found between relative humidity and the number of aerosolized bacteria. The correlation between solar irradiation and bacterial level, on the other hand, was negative. During night irrigation, up to 10 times more aerosolized bacteria were detected than with day irrigation. Wind velocity did not play an important role in the survival of aerosolized bacteria. Echovirus 7 was isolated in 4 out of 12 air samples collected 40 m downwind from the sprinkler.
Growth of Heterotrophic Bacteria and Algal Extracellular Products in Oligotrophic Waters
Authors: McFeters Gordon A. , Stuart Sidney A. , Olson Susan B.
Published: January 2020

The unexpected observation of 200 to 400 coliform bacteria per 100 ml in an unpolluted pristine stream was studied within Grand Teton National Park, Wyo. The high numbers of waterborne bacteria occurred in mid- to late summer at a location where there was a coincidental bloom of an algal mat community. Periphyton samplers were used to measure the algal growth that coincided with the increase in number of bacteria. Laboratory studies followed the growth of various coliform bacteria in the supernatant obtained from a
Chlorella
culture isolated from the mat community. Mixed natural bacterial populations from the stream and pure cultures of water-isolated fecal and nonfecal coliforms increased by two to three orders of magnitude at 13�C when grown in the algal supernatant. Radioactive algal products were obtained by feeding an axenic
Chlorella
culture
14
C-labeled bicarbonate under laboratory cultivation at 13�C with illumination. Radioactive organic material from the algae became incorporated into the particulate fraction of pure cultures of coliform bacteria as they reproduced and was later released as they died.
Comparison of Light and Electron Microscopic Determinations of the Number of Bacteria and Algae in Lake Water
Authors: Larsson Kerstin , Weibull Claes , Cronberg Gertrud
Published: January 2020

Determinations of the number of microorganisms in lake water samples with the bright-field light microscope were performed using conventional counting chambers. Determinations with the fluorescence microscope were carried out after staining the organisms with acridine orange and filtering them onto Nuclepore filters. For transmission electron microscopy, a water sample was concentrated by centrifugation. The pellet was solidifed in agar, fixed, dehydrated, embedded in Epon, and cut into thin sections. The number and area of organism profiles per unit area of the sections were determined. The number of organisms per unit volume of the pellet was then calculated using stereological formulae. The corresponding number in the lake water was obtained from the ratio of volume of solidified pellet/volume of water sample. Control experiments with pure cultures of bacteria and algae showed good agreement between light and electron microscopic counts. This was also true for most lake water samples, but the electron microscopic preparations from some samples contained small vibrio-like bodies and ill-defined structures that made a precise comparison more difficult. Bacteria and small blue-green and green algae could not always be differentiated with the light microscope, but this was easily done by electron microscopy. Our results show that transmission electron microscopy can be used for checking light microscopic counts of microorganisms in lake water.
Clear, defined medium for the sporulation of Clostridium perfringens
Authors: Sacks L E , Thompson P A
Published: January 2020

A new, defined medium for the sporulation of Clostridium perfringens is presented. Sporulation levels exceeding 10(6) to 10(7) heat-resistant spores per ml were obtained for seven strains: PS49, PS52, FD-1, T-65, NCTC strains 8798, 8238, and 10240. In the presence of theophylline, a methylxanthine, higher levels of heat-resistant spores were attained for strains PS49, PS52, FD-1, ant T-65; photomicrographs demonstrated a higher fraction of sporulating cells when these strains were grown in the presence of methylxanthines. Use of washed, highly diluted (less than 100 cells) inocula resulted in no reduction in spore yield. Strain KA3 grew well but sporulated poorly on this medium. The medium was clear and free of precipitate when small amounts (100 microgram/ml) of methylxanthine were incorporated.
Restriction endonuclease analysis for the identification of baculovirus pesticides
Authors: Miller L K , Dawes K P
Published: January 2020

Gel electrophoresis of deoxyribonucleic acid (DNA) fragments generated by digesting the DNA genomes of nuclear polyhedrosis viruses (NPV) with restriction endonucleases provides DNA fragment patterns that may be used to identify different viruses of this group. Characteristic fragment patterns were obtained for three NPVs, which are important as biological pesticides (Autographa californica NPV, Orgyia pseudotsugata NPV, and Heliothis zea NPV). The DNA fragment patterns of the A. californica NPV genoms did not change with passage through the alternate insect host, Trichoplusia ni. Heterogeneity in one preparation of O. pseudotsugata NPV was observed. The identification procedure is direct and precise. Applications of this procedure include quality control of commercial preparations of viral pesticides and screening for genetic alterations in the viruses.
Rapid test for the serological separation of staphylococci from micrococci
Authors: Seidl P H , Schleifer K H
Published: January 2020

A simple test for the serological separation of staphylococci from micrococci is described, which is based on the quite different cell wall peptidoglycan structures of these two genera. Antisera to (pentaglycyl-epsilon-amino-n-hexanoic acid)20-albumin agglutinated without exception all staphylococci and gave no positive reaction with micrococci or other bacterial cells. To obtain a good reaction, it was necessary to extract the cells with hot trichloroacetic acid for 30 min. Antisera to (tri-L-alanyl-epsilon-amino-n-hexanoic acid)22-albumin reacted strongly with micrococci containing oligo-L-alanine bridges in their peptidoglycan, but did not agglutinate staphylococci or other bacteria lacking alanine interpeptide bridges.
Improved microbiological assay procedures for dihydrostreptomycin residues in milk and dairy products
Authors: Inglis J M , Katz S E
Published: January 2020

Because dihydrostreptomycin can remain as a slowly removed antibiotic residue in dairy animals and because of the need for more sensitive procedures with which to provide information concerning antibiotic residues in food products, procedures were developed in more sensitive assays of dihydrostreptomycin in milk and some representative dairy products. The cleanup procedures that aided these improvements were (i) precipitation of milk proteins by acidification and (ii) centrifugation to extract cheeses and to remove physical barriers to diffusion in the cylinder plate assay. In addition, a thin, single seeded assay layer was used to maximize diffusion. Levels of dihydrostreptomycin as low as 0.06 microgram/ml in milk and 0.2 to 0.4 microgram/g in cheeses were measurable; these levels were some fourfold more sensitive than those presently recommended by the Food and Drug Administration.
Concentration of enteroviruses from large volumes of tap water, treated sewage, and seawater
Authors: Gerba C P , Farrah S R , Goyal S M , Wallis C , Melnick J L
Published: January 2020

Methods are described for the efficient concentration of an enterovirus from large volumes of tap water, sewage, and seawater. Virus in acidified water (pH 3.5) in the presence of aluminum chloride was adsorbed to a 10-inch (ca. 25.4 cm) fiberglass depth cartridge and a 10-inch pleated epoxy-fiberglass filter in a series at flow rates of up to 37.8 liters (10 gallons) per min. Adsorbed viruses were eluted from the filters with glycine buffer (pH 10.5 to 11.5), and the eluate was reconcentrated by using a combination of aluminum flocculation followed by hydroextraction. With this procedure, poliovirus in large volumes of tap water, seawater, and sewage could be concentrated with an average efficiency of 52, 53, and 50%, respectively. It was demonstrated that this method is capable of detecting surface solid-associated viruses originating from sewage treatment plants. No difference in virus recovery between laboratory batch studies and a set-up with acid-salt injection was found. This unified scheme for the concentration of viruses has many advantages over previously described systems. These include: high operating flow rates, low weight and small size, effectiveness with a variety of waters with widely varying qualities, and filters with a high resistance to clogging.
Pilot-scale semisolid fermentation of straw
Authors: Grant G A , Han Y W , Anderson A W
Published: January 2020

Semisolid fermentation of ryegrass straw to increase its animal feed value was successfully performed on a pilot scale. The pilot plant, which could handle 100 kg of straw per batch, was designed so that all major operations could take place in one vessel. The straw was hydrolyzed at 121 degrees C for 30 min with 0.5 N H2SO4 (7:3 liquid:solid), treated with ammonia to raise the pH to 5.0, inoculated with Candida utilis, and fermented in a semisolid state (70% moisture). During fermentation the straw was held stationary with air blown up through it. Batch fermentation times were 12 to 29 h. Semisolid fermentation did not require agitation and supported abundant growth at 20 to 40 degrees C even at near zero oxygen tensions. Fermentation increased the protein content, crude fat content, and in vitro rumen digestibility of the straw.
Microbial transformations of natural antitumor agents: oxidation of lapachol by Penicillium notatum
Authors: Otten S , Rosazza J P
Published: January 2020

The naphthoquinone lapachol (1) is readily metabolized by several fungi and streptomycetes. Preparative-scale fermentations with Penicillium notatum (UI 1602) provided a major polar metabolite (4), which was isolated and identified as an intermediate of the Hooker oxidation. The metabolite was synthesized by reacting lapachol with hydrogen peroxide under alkaline conditions.
Improved lysis of group N streptococci for isolation and rapid characterization of plasmid deoxyribonucleic acid
Authors: Klaenhammer T R , McKay L L , Baldwin K A
Published: January 2020

Procedures for effective cellular lysis and plasmid deoxyribonucleic acid (DNA) isolation from group N streptococci were developed. Cells were grown at 32 degrees C for 4 h in a modified Elliker broth containing 20 mM DL-threonine. After cellular digestion with 2 mg of lysozyme per ml for 7 min at 37 degrees C, 1% sodium dodecyl sulfate exposure resulted in complete and immediate lysis. Lactose (Lac) plasmid species in Streptococcus lactis C2 and S. cremoris B1 (30 and 37 megadaltons, respectively) were demonstrated upon examination of DNA from the cleared lysates by agarose gel electrophoresis. Increasing the lysozyme treatment to 20 min or more resulted in loss of the Lac plasmid, whereas other resident plasmids were unaffected and demonstrable in agarose gels. Diethylpyrocarbonate added before lysis prevented Lac plasmid loss in 20-min lysozyme-treated cells, but was not effective after 40 min of lysozyme treatment. The results suggested that endogenous nuclease activity during the lysozyme treatment period initiated Lac plasmid DNA loss. The development of an efficient lysis procedure for the group N streptococci allowed rapid identification and characterization of plasmid DNA by agarose gel electrophoresis. The plasmid composition of S. lactis C2 and S. cremoris B1, as determined by agarose gel electrophoresis, compared favorably to previous electron microscopic observations.
Evaluation of thermal disinfection procedures for hydrophilic contact lenses
Authors: Busschaert S C , Good R C , Szabocsik J
Published: January 2020

The kinetics and efficacy of moist heat disinfection for hydrophilic contact lenses were investigated by using representative microorganisms of ophthalmic concern and several heat-resistant species. In replicate challenges, 80 degrees C for 10 min and 75 degrees C for 5 min were proven efficacious for moist-heat disinfection.
Acute toxicity of 12,13-epoxytrichothecenes in one-day-old broiler chicks
Authors: Chi M S , Robison T S , Mirocha C J , Reddy K R
Published: January 2020

Acute toxic effects of several 12,13-epoxytrichothecenes were investigated in 1-day-old broiler chicks by single oral doses. The 7-day median lethal dose values of purified 8-acetylneosolaniol, diacetoxyscirpenol, T-2 toxin, HT-2 toxin, neosolaniol, deacetyl-HT-2 toxin, and T-2 tetraol were 3.22 +/- 0.26, 3.82 +/- 0.40, 4.97 +/- 0.44, 7.22 +/- 0.39, 24.87 +/- 2.64, 30.18 +/- 7.53 (incomplete value), and 33.79 +/- 5.39 mg/kg of body weight, respectively. Deaths occurred during the 8- to 60-h period after dosing with the tested trichothecenes. Within 4 to 10 h after dosing, inappetence, asthenia, diarrhea, and coma generally developed. Sublethal doses of each toxin decreased feed consumption and weight gain proportionally with the amounts of toxins administered. These results demonstrate that the toxic potency of 12,13-epoxytrichothecenes varies depending on the modification of side chains in the molecule.
Role of lime treatment in the removal of bacteria, enteric viruses, and coliphages in a wastewater reclamation plant
Authors: Grabow W O , Middendorff I G , Basson N C
Published: January 2020

Lime flocculation/sedimentation in the first process unit of a 4,500-m3/day wastewater reclamation plant reduced numbers of microorganisms extensively when operated at pH 11.2. The efficiency was much less at lower pH values, and some bacteria even multiplied at pH 9.6. Data on reduction in the number of microorganisms in the lime treatment and subsequent units indicate that inactivation by hydroxide alkalinity plays an important role in the efficiency of lime treatment. Reductions in the numbers of enteric viruses were higher than those of coliphages, enterococci, and total plate and coliform bacteria, which indicate that lime treatment can be monitored by means of coliphage and conventional bacteriological tests. This paper illustrates the valuable role of high-pH lime treatment in reducing the load of pathogenic microorganisms on subsequent units, including ultimate disinfection processes, which is important in the multiple safety barrier concept of wastewater reclamation processes.
Nonsporing, anaerobic, gram-positive rods in saliva and the gingival crevice of humans
Authors: Sanyal B , Russell C
Published: January 2020

Quantitative and qualitative examination of anaerobically isolated flora of the gingival crevice and saliva was carried out. It was found that half the organisms were anaerobes and that there were twice as many gram-positive organisms as there were gram-negative ones. Rods were predominant in the gingival crevice (60.5%) and cocci in saliva (69.1%). Of the total organisms, nonsporing, gram-positive anaerobic rods accounted for 24% in the gingival crevice and 9.7% in saliva. These organisms were characterized on the basis of the type of fatty acids produced from glucose and various biochemical reactions. They belonged to the following genera: Actinomyces, Propionibacterium, Arachnia, Lactobacillus, Eubacterium, and Bifidobacterium. Bifidobacteria were present only in saliva. Although members of the other genera were present both in the gingival crevice and saliva, there were considerable differences in the proportion of any particular organism (in relation to the total anaerobic viable count) between the two sites. The result of this study also indicates a greater than previously appreciated level of Propionibacterium and Arachnia in the human mouth.
Role of sediment in the persistence of enteroviruses in the estuarine environment
Authors: Smith E M , Gerba C P , Melnick J L
Published: January 2020

The survival of four enteroviruses commonly found in sewage effluents was examined when the viruses were adsorped to marine sediments in estuarine water and compared with virus survival in estuarine water alone. Echovirus 1, coxsackieviruses B3 and A9, and poliovirus 1 survived longer when associated with marine sediment. When the estuarine water was polluted with secondarily treated sewage effluent, virus survived for prolonged periods in sediments, but not in the overlaying estuarine water.
Quantification of two viruses in technical preparations of Orgyia pseudotsugata baculovirus by means of buoyant density centrifugation of viral deoxyribonucleic acid
Authors: Rohrmann G F , Martignoni M E , Beaudreau G S
Published: January 2020

A reliable method was developed for the quantitative determination of two nuclear polyhcdrosis viruses present in commercially prepared viral insecticides used against Orgyia pseudotsugata. Deoxyribonucleic acids, from nuclear polyhedrosis bundle virus and nuclear polyhedrosis single-rod virus, were separated on CsCl gradients according to their respective buoyant densities, 1.715 and 1.704 g/ml. The proportions of the two viruses were quantified by measuring the relative absorbance at 254 nm of their deoxyribonucleic acid peaks.
Effects of low concentrations of bisulfite-sulfite and nitrite on microorganisms
Authors: Wodzinski R S , Labeda D P , Alexander M
Published: January 2020

A wide range of microorganisms was tested to determine their sensitivity to low concentrations of bisulfite-sulfite and nitrite, solubility products of SO2 and NO2, respectively. Photosynthesis by blue-green algae (cyanobacteria) was more strongly inhibited by 0.1 mM bisulfite-sulfite and 1 mM nitrite at pH 6.0 than photosynthesis by eucaryotic algae and respiration of bacteria, fungi, and protozoa. At pH 7.7, blue-green algae were still more sensitive to bisulfite-sulfite and nitrite than eucaryotic algae, but the toxicity of bisulfite-sulfite and nitrite decreased as the pH increased. Photosynthesis by Anabaena flos-aquae at pH 6.0 was inhibited 25% by a bisulfite-sulfite concentration of 10 micrometer and 15% by a nitrite concentration of 50 micrometer. Photosynthesis by the blue-green alga, Lyngbya sp., was not exceptionally sensitive to chlorate and thiosulfate. Acetylene-reducing activity of Beijerinckia indica was completely inhibited by 0.1 mM bisulfite-sulfite at pH 4.0, the suppression being decreased with increasing pH.
Effect of the
Spartina alterniflora
Root-Rhizome System on Salt Marsh Soil Denitrifying Bacteria
Authors: Sherr B. F. , Payne W. J.
Published: January 2020

Nitrous oxide (N
2
O) reductase activity was used as an index of the denitrification potential in salt marsh soils. In a short
Spartina alterniflora
marsh, the seasonal distribution of N
2
O reductase activity indicated a causal relationship between
S. alterniflora
root-rhizome production and the denitrification potential of the soil system. The relationship was not discerned in samples from a tall
S. alterniflora
marsh. To further examine the in situ plant-denitrifier interaction in the short
S. alterniflora
marsh, plots with and without living
S. alterniflora
were established and analyzed for N
2
O reductase activity 5 and 18 months later. In the plots without living
Spartina
there was a significant reduction in the soil denitrification potential after 18 months, indicating that in the SS marsh the denitrifiers are tightly coupled to the seasonal production of below-ground
Spartina
macroorganic matter. In plots with intact
Spartina
, the soil denitrification potential was not altered by NH
4
NO
3
or glucose enrichment. However, in plots without living
Spartina
, there were significant changes in soil N
2
O reductase activity, thus indicating that the plants can serve as a “buffer” against this form of pulse perturbation.
Evaluation of the Accuracy and Precision of Enumerating Aerobic Heterotrophs in Water Samples by the Spread Plate Method
Authors: Kaper James B. , Mills Aaron L. , Colwell Rita R.
Published: January 2020

Factors associated with accuracy and precision in the enumeration of aquatic aerobic heterotrophs by the spread plate method were evaluated by using a nested analysis of variance experimental design. Variances associated with individual components of the spread plate procedure were isolated, and optimal replications of each step were allocated. A practical scheme for optimal allocation of resources is proposed, consisting of four subsamples and two plates per subsample and yielding a total variance decrease of 70% from a single-subsample, 10-plate series. Data transformation was, in general, unnecessary for intraexperiment or intrasample statistical analysis, whereas interexperiment or intersample comparisons may require transformation of data. Rapid changes in the numbers of organisms in stored water samples were observed that were not reproducible and did not follow detectable trends, with increases or decreases in counts occurring in samples regardless of whether they were stored at room temperature or refrigerated, or stored in plastic or glass containers. Rapid sample handling is strongly recommended to minimize variations in the microbial populations of samples for aquatic environments.
Use of ethanol for selective isolation of sporeforming microorganisms
Authors: Koransky J R , Allen S D , Dowell V R
Published: January 2020

When mixed cultures containing sporeforming bacteria were treated with heat or with ethanol, the latter consistently resulted in better recovery of Clostridium and Bacillus species. Both techniques were effective in eliminating vegetative cells. An ethanol concentration greater than 25% and exposure for 45 min or longer were necessary to kill all vegetative cells in mixed-culture samples. Ethanol treatment (50% ethanol for 1 h) was effective for isolating sporeforming bacteria from intestinal specimens. Seven different species of Clostridium were the only bacteria isolated from the ethanol-treated specimen of intestinal contents from the large bowel of a patient. It was concluded that treatment with ethanol for 1 h is an effective technique for selective isolation of sporeforming bacteria from mixed cultures and certain types of clinical specimens.
Catabolism of 2,4,5-trimethyoxybenzoic acid and 3-methoxycrotonic acid
Authors: Lee Y L , Sparnins V L , Dagley S
Published: January 2020

4-Methoxygentisic acid was an intermediate formed when Arthrobacter degraded, 2,4,5-trimethoxybenzoic acid. Isolates of Pseudomonas and Arthrobacter from soil grew at the expense of 3-methoxycrotonic acid. Evidence is presented that enzymatic hydration, with elimination of methanol, accounted for replacement of the methoxyl group of 3-methoxycrotonic acid and also of one methoxyl group of 2,4,5-trimethoxybenzoic acid.
Bacteria from the Gut of Australian Termites
Authors: Eutick M. L. , O'Brien R. W. , Slaytor M.
Published: January 2020

The major gut bacteria of the worker caste of nine species of Australian termites, belonging to four families, were isolated and identified to generic level. All species were either facultative anaerobes or strict aerobes. A correlation appears to exist between the major gut bacterium and the family to which the termite belongs. The major bacterium from the two lowest termites,
Mastotermes darwiniensis
(family
Mastotermitidae
) and
Cryptotermes primus
(family
Kalotermitidae
), was
Streptococcus
; from four species belonging to the
Rhinotermitidae (Heterotermes ferox, Coptotermes acinaciformis, C. lacteus, Schedorhinotermes intermedius intermedius)
it was
Enterobacter
; and from three species of the
Termitidae (Nasutitermes exitiosus, N. graveolus, N. walkeri)
it was
Staphylococcus. Enterobacter
was a minor symbiont of
M. darwiniensis, C. primus
, and
N. graveolus; Streptococcus
was a minor symbiont of
H. ferox, C. lacteus, S. intermedius intermedius
, and
N. exitiosus
; and
Bacillus
was a minor symbiont of
C. acinaciformis
and
S. intermedius intermedius. M. darwiniensis
possessed another minor symbiont tentatively identified as
Flavobacterium. C. acinaciformis
from three widely separated locations possessed a similar microbiota, indicating some form of control on the composition of the gut bacteria. Bacteria, capable of growth on N-free medium in the presence of nitrogen gas, were isolated from all termites, except
N. exitiosus
and
N. walkeri
, and were identified as
Enterobacter.
No cellulose-degrading bacteria were isolated.
"Bactericidal" property of seawater: death or debilitation?
Authors: Dawe L L , Penrose W R
Published: January 2020

Coliform colony-forming units in sewage-contaminated seawater were observed to decrease rapidly with time in water that was collected from St. John's Harbour, Newfoundland, and isolated in dialysis bags; this confirms observations made in warmer climates. Adenosine 5'-triphosphate biomass, however, did not decline, nor did the particle size distribution of radioactively labeled coliforms change. It was observed that the coliforms were not killed by seawater but were debilitated to the extent that they would not form colonies on selective media. However, they recovered and grew on nutrient agar made with seawater. The adenosine 5'-triphosphate content per cell apparently did not decline during debilitation.
Enumeration and isolation of anaerobic microbiota of piggery wastes
Authors: Spoelstra S F
Published: January 2020

Media for enumeration of the microbiota of anaerobically stored piggery wastes were tested. Highest colony counts were obtained with 80 to 100% farm slurry supernatant included in the anaerobic roll tube media. Colony counts with these media numbered 2 X 10(9) to 12 X 10(9)/g (wet weight), which represents about 20% of the microscopic counts. Lower percentages of slurry supernatant in the media gave lower colony counts. Addition of glucose, cellobiose, and starch or of Trypticase to media with 20% slurry supernatant did not increase colony counts. Higher values were obtained when hemicellulose preparations were added to these media. Incubation at 25 degrees C gave the highest numbers. Incubation at 15 to 37 degrees C gave counts of about 70 and 10%, respectively, of those at 25 degrees C. Of the colonies picked for isolation, about 20% were obtained in pure culture. The isolates apparently belonged to the genera Peptococcus, Ruminococcus, Peptococcus, Ruminococcus, Pepostreptococcus, and Bacteroides.
Three-year investigation of the natural airborne bacterial flora at four localities in sweden
Authors: Bovallius A , Bucht B , Roffey R , Anäs P
Published: January 2020

The concentration of airborne bacteria was recorded during a period of 3 years at four localities: (i) in an agricultural district with an average of 99 (range, 2 to 3,400) bacteria per m3; (ii) in a coastal area with an average of 63 (range, 0 to 560) bacteria per m3; (iii) in a city park with an average of 763 (range, 100 to 2,500) bacteria per m3; and (iv) in a city street with an average of 850 (range, 100 to 4,000) bacteria per m3. At all four localities the bacterial concentrations varied within broad limits, but an annual periodicity with high average counts found during summer and autumn could be seen. The influence of certain meteorological factors on the number of airborne bacteria is also reported. Rain or high relative humidity caused a decrease in the bacterial counts, while high temperature or high wind velocities increased the counts. The particle size distribution for the four localities showed that about 50% of the particles carrying bacteria were larger than 8 micrometer.
Bacterial dehalogenation of halogenated alkanes and fatty acids
Authors: Omori T , Alexander M
Published: January 2020

Sewage samples dehalogenated 1,9-dichloronane, 1-chloroheptane, and 6-bromohexanoate, but an organism able to use 1,9-dichlorononane as the sole carbon source could not be isolated from these samples. Resting cells of Pseudomonas sp. grown on n-undecane, but not cells grown on glycerol, dehalogenated 1,9-dichlorononane in the presence of chloramphenicol. Resting cells of five other n-undecane-utilizing bacteria cleaved the halogen from dichlorononane and 6-bromohexanoate, and four dehalogenated 1-chloroheptane; however, none of these organisms used 1,9-dichlorononane for growth. By contrast, four benzoate-utilizing bacteria removed bromine from 6-bromohexanoate but had little or no activity on the chlorinated hydrocarbons. Incubation of sewage with 1,9-dichlorononane increased its subsequent capacity to dehalogenate 1,9-dichlorononane and 6-bromohexanoate but not 1-chloroheptane. A soil isolate could dehalogenate several dichloralkanes, three halogenated heptanes, and halogen-containing fatty acids. An enzyme preparation from this bacterium released chloride from 1,9-dichlorononane.
Bacterial sampling techniques on beef, pork, and lamb adipose tissue
Authors: Berry B W , Joseph A L , Chen A A
Published: January 2020

Two methods were used to evaluate bacterial recovery from beef, pork, and lamb adipose tissue. Higher counts were obtained with a tissue removal and fluid agitation technique (shaking) than with surface swabbing, but only when bacterial levels were low. Bacterial recovery by both methods was unaffected by specie origin of adipose tissue and differences in surface texture, sample storage time (12 versus 6 days), and duration fluid agitation (5 versus 10 min).