Turnover of dhurrin in green sorghum seedlings. [Sorghum bicolor]

Journal Article · Thu Nov 01 00:00:00 EST 1990 · Plant Physiology; (USA)

DOI:https://doi.org/10.1104/pp.94.3.1219· OSTI ID:5726078

Adewusi, S R.A. ^[1]

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1. Obafemi Awolowo Univ., Ile-Ife (Nigeria)

The turnover of dhurrin in green seedlings of Sorghum bicolor (Linn) Moench var Redland x Greenleaf, Sudan 70 has been investigated using glyphosate and pulse-labeling studies with {sup 14}C-tyrosine and ({sup 14}C)shikimic acid. The rate of dhurrin breakdown was 4.8 nanomoles per hour in the shoot and 1.4 nanomoles per hour in the root. The rate of dhurrin accumulation in the shoot of 4- to 5-day-old seedlings was high but decreased with age until at the peak period of dhurrin accumulation, the rates of dhurrin synthesis and breakdown were equal. Using a first order equation (an approximation) the rate of dhurrin synthesis (which equals accumulation plus breakdown rates) was 17.4 nanomoles per hour in the shoot and 4.1 nanomoles per hour in the root. In both tissues, the breakdown rate was between 27 and 34% of their synthetic capacity within the experimental period. Dhurrin synthesis in green sorghum seedlings occurred in both the light and dark photoperiods but was faster in the dark period. The result is discussed in relation to the possible metabolic roles of the turnover.

• OSTI ID: 5726078
• Journal Information: Plant Physiology; (USA), Vol. 94:3; ISSN 0032-0889
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
GLYCOSIDES
BIOCHEMICAL REACTION KINETICS
SORGHUM
PHYSIOLOGY
CARBON 14 COMPOUNDS
CYANATES
SEEDLINGS
SHIKIMIC ACID
TRACER TECHNIQUES
TYROSINE
AMINO ACIDS
CARBOHYDRATES
CARBONIC ACID DERIVATIVES
CARBOXYLIC ACIDS
CEREALS
GRAMINEAE
HYDROXY ACIDS
ISOTOPE APPLICATIONS
KINETICS
LABELLED COMPOUNDS
LILIOPSIDA
MAGNOLIOPHYTA
NITROGEN COMPOUNDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
PLANTS
REACTION KINETICS
550201* - Biochemistry- Tracer Techniques