Avocado mesocarp

A long-chain dihydroxy compound, isolated from Avocado mesocarp, inhibited soybean callus growth and induced elongation of wheat coleoptiles. This compound was identified as 1-acetoxy-2,4-dihydroxy-n-heptadeca-16-ene, otherwise known as avocado inhibitor (14). 

Avocado inhibitor (l-Acetoxy-2,4-dihydroxy-n-heptadeca-16-ene) Avocado mesocarp... 

All plant extracts that synthesize fatty acids from acetyl-CoA and mal-onyl-CoA are completely dependent upon the presence of ACP (Stumpf, 1977 Ohlrogge et al., 1979). In addition, its role as the thioester component of the primary elongation substrate, namely, palmityl-ACP, and the first desaturation substrate, stearyl-ACP, is well documented (Jaworski and Stumpf, 1974 Jaworski et al., 1974). Two plant ACPs have been isolated and characterized, one from avocado mesocarp and one from spinach leaves (Simon et al., 1967). The characteristics of these ACPs, as compared to prokaryotic ACPs, are given in Table I. 

Thus, it is apparent that the de novo system, palmitoyl-ACP synthetase, occurs in a wide variety of plants (potato tuber, avocado mesocarp, developing safflower and soybean seeds, and spinach chloroplast) which synthesize the primary product, palmitoyl-ACP, by the utilization of acetyl-ACP and malonyl-ACP. 

CCC, Phosphon D and AMO-1618 did not affect the biosynthesis of mevalonic acid in the avocado mesocarp [20]. Alar inhibited GA synthesis but did not affect ABA synthesis [22]. The difference in results obtained may be due to the concentration of plant growth retardant applied. 

Idioblasts separated from avocado mesocarp by enzymatic digestion overnight and further centrifugation were also responsive to stimulation by ethylene. The cells responded to ethylene as a function of temperature maximal increase in the diene content was observed at 35°C. At this temperature, a time course study showed that a minimum of 1 h of treatment is required for the cells to respond to the stimulus by increasing their diene content. This behaviour continued for at least 3h. 

The lack of response by pericarp alone suggests that avocado mesocarp may be responsible for the changes in the diene levels in the pericarp. Idioblast oil cells from avocado mesocarp are also susceptible to stimulation the effect of ethylene on their antifungal diene induction is time and temperature dependent. 

Several tissues have been used to study the mechanism of fatty acid synthesis, particularly the avocado mesocarp, spinach and lettuce chloroplasts, and etiolated barley seedlings, but some major advances have been made from studies of maturing oil-bearing seeds, e.g. castor bean (in which 90% of the fatty acid content is ricinoleic acid) and safflower, Carthamus tine tor ius (76% linoleic and 1% oleic). Oleic acid plays a central role in plant fatty acid anabolism as the precursor of the major unsaturated fatty acids, e.g. it is the first detectable fatty acid formed when acetate is fed to the developing castor bean and is itself a precursor of ricinoleic acid. 

In a variety of oil rich tissues, including avocado mesocarp, castor bean endosperm, and cotyledons of linseed and safflower, plastids have been shown to have high rates of FAS activity. The assumption of exclusivity of fatty acid synthesis to the plastid seems reasonable, though not proven to the high degree of exactness for leaf tissue. ... 

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