A MICROBIOLOGICAL ASSAY FOR BIOTIN IN SEAWATER

1963 ◽  
Vol 9 (3) ◽  
pp. 403-409 ◽  
Author(s):  
N. J. Antia
Keyword(s):  
Growth Response ◽  
Marine Bacterium ◽  
Microbiological Assay ◽  
Synthetic Seawater ◽  
Seawater Samples ◽  
Seawater Medium

A method is described for the direct bioassay of biotin in seawater samples. The assay organism is an unidentified marine bacterium that shows a growth response, in enriched seawater medium, proportional to dissolved biotin concentration in the range 3–12 μμg/ml. The growth was measured turbidimetrically with a spectrophotometer. The effective assay range was extended successfully to higher biotin levels by making appropriate dilutions in synthetic seawater.

Determination of Seawater Salinity by Ultraviolet Spectroscopic Measurements

1997 ◽  
Vol 51 (9) ◽  
pp. 1294-1302 ◽  
Author(s):  
Vito Di Noto ◽  
Mauro Mecozzi
Keyword(s):  
Organic Matter ◽  
Uv Spectroscopy ◽  
Sample Pretreatment ◽  
Uv Spectra ◽  
Linear Calibration ◽  
Synthetic Seawater ◽  
Seawater Salinity ◽  
Seawater Samples ◽  
Nitrate Species

A method for the determination of seawater salinity by ultraviolet (UV) spectroscopy is proposed. The effects of single salt concentrations and of salinity on UV absorption in the 190–250-nm range were investigated. These studies revealed that the absorption spectrum of a solution with a given salinity is due mainly, in order, to KBr >MgCl 2>NaCl. The influence of the temperature and salt concentration on UV spectra was studied by using synthetic seawater samples with the salinities ranging from 1 to 50 parts per thousand (%). Results showed that, in the absence of interferences, the most sensitive and reliable conditions for measuring the salinity are at 212 nm and at temperatures in the range of 25–30 °C. Under these conditions this method shows quite linear calibration curves and allows us to perform salinity determinations in seawater solutions at concentrations as low as 4%. Moreover, it requires no sample pretreatment and offers a precision of 0.20%. The proposed method is very simple and rapid for laboratory and on-board analysis. Finally, the interference of organic matter, nitrite, and nitrate species with the salinity determinations was investigated. These studies show that organic matter does not interfere at concentrations of carbon lower than 1 mg/L and at 210 nm. Interferences due to NO− x species can be ignored if these species are dissolved in solution at concentrations lower than ≈0.2 mg/L and the analyses are carried out at wavelengths lower than 212 nm.

The Vitamin B12 Content of Certain Fishery Materials

1953 ◽  
Vol 10 (2) ◽  
pp. 64-68 ◽  
Author(s):  
B. A. Southcott ◽  
H. L. A. Tarr
Keyword(s):  
Vitamin B12 ◽  
Chromatographic Separation ◽  
Growth Response ◽  
Microbiological Assay ◽  
Vitamin B ◽  
Hexane Extraction ◽  
Clupea Pallasi ◽  
Assay Procedure ◽  
Lactobacillus Leichmannii

Irregularities occurring in the microbiological assay of herring (Clupea pallasi) materials for vitamin B12 (cobalamin) are described and the probable reasons for the differences discussed. With the employment of a Lactobacillus leichmannii assay procedure and conditions under which vitamin B12 (cyano-cobalamin) and vitamin B13a (hydroxo-cobalamin) caused identical growth response, it was found that normal commercial flame-dried herring meals had about the same total cobalamin content as specially prepared meals dried at 38° to 43.5 °C. Chromatographic separation, elution and assay of the cobalamins in herring-meal samples indicated that substantially all of the activity found by direct assays of the meals was due to the vitamin itself. Hexane extraction had little effect on the cobalamin content, but heating the meals reduced it.

Some patterns of B vitamin requirements among neritic marine bacteria

1968 ◽  
Vol 14 (5) ◽  
pp. 537-543 ◽  
Author(s):  
Paul R. Burkholder ◽  
Seymour Lewis
Keyword(s):  
Marine Bacteria ◽  
Similarity Coefficient ◽  
Thiamine Pyrophosphate ◽  
Vitamin B ◽  
Synthetic Seawater ◽  
Vitamin Requirements ◽  
Casamino Acids ◽  
B Vitamin ◽  
Pyrimidine Moiety ◽  
Seawater Medium

Twenty-four different patterns of single and multiple requirements for various B vitamins were demonstrated for 665 cultures of marine bacteria grown in a basal synthetic seawater medium enriched with phosphate, vitamin-free casamino acids, dextrose, and succinate. Among 114 thiamine-requiring isolates, 55 were unable to make the pyrimidine moiety, 19 required thiazole, 13 needed both thiazole and the pyrimidine moiety, while 27 organisms required thiamine or thiamine pyrophosphate for growth. Among 142 biotin requirers, 22 had to be supplied with biotin, 60 could use either biotin or biocytin, 54 were able to respond to either biotin, biocytin, or desthiobiotin. Only six cultures could not use biocytin, and required either biotin or desthiobiotin. Various responses of vitamin B12 requiring cultures indicated special types of specificity for cyanocobalamin and analogues of this vitamin. Computer-sorting at the 0.66 similarity coefficient breaking point arranged a group of 104 isolates into eight clusters. The isolates having biotin or thiamine requirements, single or in combination with other vitamin needs, appeared to be randomly scattered through the eight clusters.

Effect of Sodium Chloride and Potassium Chloride on Growth Response of Yeasts Saccharomyces uvarum and Kloeckera brevis to Free Vitamin B6

1984 ◽  
Vol 67 (3) ◽  
pp. 617-620
Author(s):  
Tomas R Guilarte
Keyword(s):  
Sodium Chloride ◽  
Potassium Chloride ◽  
Acid Hydrolysis ◽  
Salt Concentration ◽  
Vitamin B6 ◽  
Growth Response ◽  
Extraction Procedure ◽  
Food Samples ◽  
Microbiological Assay ◽  
Saccharomyces Uvarum

Abstract Acid hydrolysis is the most commonly used extraction procedure for the microbiological assay of vitamin B6 in food samples. Because NaCl or KC1 is formed as a result of the extraction procedure, these 2 salts were tested as possible agents that may influence the growth response of the yeasts Saccharomyces uvarum and Kloeckera brevis. Results indicate that NaCl and KC1 do effect the growth response of these 2 yeasts, depending on the salt concentration and the B6 vitamer present.

Environmental control of gametogenesis in Laminaria saccharina. II. Correlation of nitrate and phosphate concentrations with gametogenesis and selected metabolites

1973 ◽  
Vol 51 (5) ◽  
pp. 829-839 ◽  
Author(s):  
Stephen I. C. Hsiao ◽  
Louis D. Druehl
Keyword(s):  
Female Gametophyte ◽  
Environmental Control ◽  
Male Gametophyte ◽  
Axenic Culture ◽  
Nutrient Concentrations ◽  
Growth Morphology ◽  
Laminaria Saccharina ◽  
Synthetic Seawater ◽  
Sexual Fusion ◽  
Seawater Medium

The gametophyte growth, morphology, gametogenesis, and metabolites of Laminaria saccharina (L.) Lamouroux were studied in different cyncentrations of nitrate and phosphate in axenic culture, using a synthetic seawater medium under optimal light and temperature conditions.Nitrate and phosphate were required for the various stages of gametophyte development and gametogenesis. Under nitrate and phosphate concentrations optimal for growth and gametogenesis, maximum quantities of DNA, RNA, protein, and carbohydrate, and low quantities of lipid were produced. Further, nutrient concentrations which gave rise to the greatest fertility also gave rise to the highest ratios of RNA/DNA and protein/RNA.Antheridial production occurred over a wider range of nitrate and phosphate concentrations than oogonial production. Further, percentage fertility was greater for the male gametophyte. This indicated that the female gametophyte was the limiting agent in sexual fusion.

Use of glycerol-cryoprotected Lactobacillus casei for microbiological assay of folic acid.

1982 ◽  
Vol 28 (5) ◽  
pp. 1198-1200 ◽  
Author(s):  
S D Wilson ◽  
D W Horne
Keyword(s):  
Growth Rate ◽  
Folic Acid ◽  
Lactobacillus Casei ◽  
Growth Response ◽  
Simple Procedure ◽  
Inoculum Size ◽  
Microbiological Assay ◽  
Rat Tissues ◽  
Overnight Incubation ◽  
Low Concentrations

Abstract A simple procedure for preparing glycerol-cryoprotected Lactobacillus casei cultures has been developed. L. casei grown in medium supplemented with low concentrations of folic acid (0.3 micrograms/L) is diluted with an equal volume of glycerol (800 mL/L) and stored at -20 degrees C. Growth response of the glycerol-cryoprotected L. casei to low concentrations of folic acid exceeded that of cultures maintained by monthly agar stab transfer. Also, growth for the zero-folate blanks was considerably less for the cryoprotected cultures. Assay of folate in several rat tissues correlated well (r = 0.999) with the standard microbiological assay. The growth rate of the culture depends on the inoculum size, and a heavy inoculum of cryoprotected L. casei may be used to complete the assay after only an overnight incubation.

scholarly journals Genome Sequence of Cobetia sp. Strain MM1IDA2H-1, a Hydrocarbon-Degrading and Biosurfactant-Producing Marine Bacterium

2017 ◽  
Vol 5 (15) ◽  
Author(s):  
Claudia Ibacache-Quiroga ◽  
Christian Canales ◽  
Mariam Charifeh ◽  
M. Alejandro Dinamarca
Keyword(s):  
Quorum Sensing ◽  
Carbon Source ◽  
Aromatic Hydrocarbon ◽  
Genome Sequence ◽  
Sole Carbon Source ◽  
Marine Bacterium ◽  
Bacterial Quorum Sensing ◽  
Bacterial Quorum ◽  
Seawater Samples

ABSTRACT Cobetia sp. strain MM1IDA2H-1 is a marine bacterium isolated from seawater samples that uses the heterocyclic aromatic hydrocarbon dibenzothiophene as the sole carbon source and produces a biosurfactant that inhibits bacterial quorum sensing. The Cobetia sp. MM1IDA2H-1 genome was sequenced, processed, assembled, and annotated for basic and applied studies.

Lactobacillus casei microbiological assay of folic acid derivatives in 96-well microtiter plates.

1988 ◽  
Vol 34 (11) ◽  
pp. 2357-2359 ◽  
Author(s):  
D W Horne ◽  
D Patterson
Keyword(s):  
Folic Acid ◽  
Rat Liver ◽  
Data Reduction ◽  
Biological Samples ◽  
Lactobacillus Casei ◽  
Growth Response ◽  
Microtiter Plate ◽  
Microbiological Assay ◽  
Microtiter Plates ◽  
Modern Computer

Abstract Microbiological assay is still widely used for estimating folic acid derivatives in serum and other biological samples. We describe here a modification of this procedure involving use of 96-well microtiter plates. This procedure, used with modern, computer-interfaced microtiter-plate readers and data-reduction software, greatly shortens the time and minimizes reagent costs for this assay. Under the conditions of our assay procedures, all folic acid derivatives tested gave equal growth response for Lactobacillus casei. Results for assays of rat liver extracts showed excellent agreement between the standard bioassay and the 96-well procedure.

Investigation of 3-amino-1,2,4-triazole azodye derivatives as reagents for determination of mercury(II)

2008 ◽  
Vol 62 (6) ◽  
Author(s):  
Abdalla Khedr
Keyword(s):  
Extinction Coefficient ◽  
Tap Water ◽  
Simple Procedure ◽  
Aqueous Media ◽  
High Sensitivity ◽  
Complexation Reaction ◽  
Synthetic Seawater ◽  
Sensitivity And Selectivity ◽  
Seawater Samples

AbstractThe reaction of mercury(II) with 3-(2,4-dihydroxyphen-1-ylazo)-1,2,4-triazole (HL1), 3-(2-hydroxy-5-methylphen-1-ylazo)-1,2,4-triazole (HL2), 3-(2-hydroxy-5-ethoxycarbonylphen-1-ylazo)-1,2,4-triazole (HL3), 3-(2-hydroxy-5-acetylphen-1-ylazo)-1,2,4-triazole (HL4), 3-(2-hydroxy-5-formylphen-1-ylazo)-1,2,4-triazole (HL5), and 3-(2-hydroxy-5-bromophen-1-ylazo)-1,2,4-triazole (HL6) was studied. A new, direct, and simple procedure was suggested for the spectrophotometric determination of mercury(II) based on its complexation reaction with HL1-HL6. The best reagent was found to be HL3 due to its high sensitivity and selectivity. In aqueous media of pH 9.0 containing 40 vol. % of methanol, Hg(II) reacts with HL3 to form a 1:2 (Hg(II) · HL3) complex having a sensitive absorption peak at 490 nm with the molar extinction coefficient of 3.31 × 104 L mol−1 cm−1 using 4 × 10−4 M of the reagent. Beer’s law is obeyed over the range from 0.00 µg mL−1 to 12.04 µg mL−1 of mercury(II). The proposed method was applied in the determination of mercury(II) in tap water, seawater and synthetic seawater samples, without the need of prior treatment, with satisfactory results.

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