Seasonal variation of abscisic acid in the dormant shoots of Douglas-fir

The occurrence of abscisic acid (ABA) in the dormant shoots of Douglas-fir (Pseudotsuga menziesii (Mirb.) Franco) was confirmed by bioassay, thin-layer chromatography, gas–liquid chromatography, and gas–liquid chromatography – mass spectrometry. Seasonal variation of ABA in the buds, leaves, and stems was then determined using 2-trans-ABA as an internal standard. Concentrations of ABA were highest in the autumn for buds (2.1 μg/g) and needles (0.79 μg/g) and highest in January for stems (0.34 μg/g). The lowest concentrations for all tissues were in February and March, before bud burst. Close correlation of levels of ABA with previously measured physiological evidence of growth and metabolic activity suggests a possible role in the dormancy cycle of Douglas-fir.

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THE IDENTIFICATION OF C19-16-UNSATURATED STEROIDS AND ESTIMATION OF 17-OXOSTEROIDS IN BOAR SPERMATIC VEIN PLASMA AND URINE

Journal of Endocrinology ◽

10.1677/joe.0.0470357 ◽

1970 ◽

Vol 47 (3) ◽

pp. 357-368 ◽

Cited By ~ 25

Author(s):

D. B. GOWER ◽

F. A. HARRISON ◽

R. B. HEAP

Keyword(s):

Mass Spectrometry ◽

Liquid Chromatography ◽

Thin Layer ◽

Spermatic Vein ◽

Gas Liquid Chromatography ◽

Liquid Chromatography Mass Spectrometry ◽

Layer Chromatography ◽

Hydrolysis Of ◽

Free Steroid ◽

Steroid Conjugates

SUMMARY C19-16-unsaturated steroids have been extracted from the urine and spermatic vein plasma of a mature boar and identified by thin-layer chromatography, gas—liquid chromatography and combined gas—liquid chromatography—mass spectrometry. 5α-Androst-16-en-3β-ol (approximately 250 μg./1.) was identified in the urinary glucuronide fraction. This compound and the 3α-epimer occurred in the spermatic vein plasma predominantly as sulphates but a small quantity of the 3α-isomer was extractable with ether prior to hydrolysis of steroid conjugates. Traces of 5,16-androstadien-3β-ol have been tentatively identified in the plasma sulphate fraction; 5α-androst-16-en-3-one occurred as free steroid. No 16-unsaturated steroids were found in the plasma glucuronide nor in urinary sulphate fractions. The latter contained an unidentified compound of similar polarity to the C19-16-unsaturated steroids. Neutral 17-oxosteroids were measured in extracts obtained from both the urine and spermatic vein plasma. Of the dehydroepiandrosterone (DHA) in the urine 60% occurred as sulphate and 40% as glucuronide with only traces as free steroid. Androsterone and aetiocholanolone occurred only as glucuronides. In the spermatic vein plasma, DHA occurred predominantly as sulphate with small amounts as glucuronide and free steroid.

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Concentrations of non-glucose polyols in serum and cerebrospinal fluid from apparently healthy adults and children.

Clinical Chemistry ◽

10.1093/clinchem/30.2.188 ◽

1984 ◽

Vol 30 (2) ◽

pp. 188-191 ◽

Cited By ~ 6

Author(s):

S Yoshioka ◽

S Saitoh ◽

S Seki ◽

K Seki

Keyword(s):

Mass Spectrometry ◽

Cerebrospinal Fluid ◽

Liquid Chromatography ◽

Healthy Subjects ◽

Metabolic Diseases ◽

Gas Liquid Chromatography ◽

Liquid Chromatography Mass Spectrometry ◽

Adults And Children ◽

Healthy Persons ◽

Apparently Healthy

Abstract Six non-glucose polyols--mannose, fructose, 1-deoxyglucose, mannitol, glucitol, and inositol--were identified and evaluated in human serum and cerebrospinal fluid by gas-liquid chromatography and by gas-liquid chromatography/mass spectrometry. Concentrations of fructose, mannose, and inositol in the serum of healthy persons or children without metabolic diseases varied with age, as already reported for 1-deoxyglucose. Fructose, inositol, and glucitol concentrations in cerebrospinal fluid significantly exceeded those in serum. The method described here for determining polyols and for evaluating polyol patterns in serum, as well as the resulting data on children and healthy subjects, should be useful in investigations of the clinical and physiological significance of polyols.

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