Stress compounds

To test if some stress compounds had beneficial effects on aphids proline, choline and glycine-betaine were incorporated into artificial diets. Proline and choline appeared to decrease survival of aphids, while glycine-betaine did not (Table V). Moreover, glycine-betaine caused a drastic increase in aphid reproduction. Thus, the increased susceptibility to aphids of water stressed plants may be partially due to the higher content of glycine-betaine. 

This chapter follows the pattern of previous Reports with the various sesquiterpenoids considered in structural groups based on their postulated or established biosynthesis. Interest in sesquiterpenoid structure, synthesis, and biosynthesis has continued at a high level during the period covered by the present Report. Two excellent reviews have been published one provides an up-to-date account of sesquiterpenoid biosynthesis while the other provides an authoritative description of studies on sesquiterpenoid stress compounds. Stress metabolites are produced by plants after infection with fungi, bacteria, and viruses or after mechanical wounding, irradiation with u.v. light, dehydration, cold, or treatment with phytotoxic agents. 

All dihalides of Eu, Sm, and Yb are known, but less is known of the dihalides of Nd and Tm. Of the structures of the Yb dihalides only that of Ybl2(Cdl2 structure) appears to be known. The structures of Eu and Sm dihalides are summarized in Table 9.15 (p. 353) and the accompanying text, where the similarity to the alkaline-earth compounds is stressed. Compounds MIj formed from the metal and MI3 by La, Ce, Pr, and Gd are not compounds of M(ii), but have metallic properties and may be formulated (e). 

Carrete, R., Vidal, M.T., Bordons, A., and Constanti, M. 2002. Inhibitory effect of sulfur dioxide and other stress compounds in wine on the ATPase activity of Oenococcus oeni. FEMS Microbiol. Lett. 211, 155-159. 

The terpenoid stress compound phytuberin has been found in leaves of Nicotiana species. It has been produced in response to tobacco mosaic virus (TMV), tobacco necrosis virus (TNV) or the bacterium Pseudomanas lachrymans. Potato tubers inoculated29 with microorganisms accumulates the stress metabolite phytuberin, which is liquid antifugal sesquiterpene. It has been represented30 by the following structure ... 

Phytuberin has also been found32 in tobacco leaves infiltrated with Pseudomonas Solanacearum. In addition phytuberin was isolated from Pseudomonas Solanacearum U-7. The methylene chloride extract from the callus contained phytuberin (55) and phytuberol (56). Both (55) and (56) were absent from healthy tissues. They were identified33 as stress compounds in leaves ofNocotianatabacum CV SamsunNN. sylvestris. 

Fujimori, T., R. Uegaki, S. Kubo, and K. Kato Sesquiterpenoids, stress compounds from tobacco leaves 34th Tobacco Chemists Research Conference, Program Booklet and Abstracts, Vol. 34, Paper No. 24, 1980, p. 13. 

Uegaki, R., T. Fujimori, S. Kubo, and T. Kato Sesquiterpenoid stress compounds from Nicotiana rus-tica inoculated with TMV Phytochemistry 22 (1983) 1193-1195. 

The structure of aubergenone was revised to that of (24) by Mural and coworkers (Ref. 37). The revised structure, 11-hydroxy-4a,5a-eudesm-l-en-3-one (24) is the only stress compound with a 5a-eudesmane skeleton among the Solanaceae metabolites and hence stands on unique blogenetlc grounds (Ref. 37). 

Tomato - Lycopersicon esculentum. The tomato has not been Investigated as thoroughly as potatoes, and the only sesqulterpenold stress compound so far Identified Is rlshltln (1), the main potato phytoalexin (Ref. 38). The tomato derived extracts from which rlshltln can be Isolated are complex. It Is likely that other sesqulterpenolds will be Isolated from these complex mixtures in time (Ref. 8). 

A Stoessl, E. W. B. Ward and J. B. Stothers, "Biosynthetic Relationships of Sesqulterpenoidal Stress Compounds from the Solanaceae", in P. A. Hedln, ed.. Host Plant Resistance to Pests, Amer. Chem. Soc., Washington, DC, 1977, pp. 61-77. 

R. Uegaki, T. Fujimori, S. Kubo and K. Kato, "Sesquiterpenoid Stress Compounds from Nicotlana Species", Phytochemistry, 20, 1567-1568 (1981). 

In a continuing investigation of sesquiterpenoid stress compounds from Nicotiana species it has been shown that phytuberin (566) and phytuberol (567) are produced on treatment of N. tabacum with the ethylene-releasing substance ethrel (2-chloroethylphosphonic acid). Phytuberol is also generated on inoculation of N. rustica with tobacco mosaic virus (TMV), and solavetivone (568)... 

An adhesively bonded joint is typically more structurally efficient than a mechanically fastened joint. Fasteners introduce discrete, or at least concentrated, points at which load is transferred from one component to another. Therefore the peak stress at each fastener is much higher than overall joint stress and the joint must be suitably designed to withstand these peak stresses. Compounding this is the fact that aerospace components are typically quite thin with proportionately low fastener bearing strength. The most efficient way to mechanically fasten thin members is with numerous small fasteners which add weight and cost. 

Although most phytoalexins in the Fabaceae are of isofla-vonoid origin, a-hydroxydihydrochalcone (75), odoratol (76), and methylodoratol (77) are formed de novo as stress compounds in the pods and cotyledons of Lathyrus odoratus (Fuchs et al., 1984). 

Stoessl, a., Stress compound formation in the interaction of potato tubers with A/rernam solani and A. solani metabolites. Physiol. Plant Path., 20, 263-273 (1982). 

Product brochures, Ultra Low Stress Compound EME 6710 (Sept. 1989) and Super Low Stress Epoxy Molding Compound Sumikon EME-630019300 Series For VLSI Sumitomo-Bakelite Co., Ltd., Tokyo, Japan. 

Fig. 12.6 pXRD profiles of wet and dry granulated MBP stored under various levels of stress (Compound Z)... 

Steele CL, Katoh S, Bohlmann J, Croteau R (1998) Regulation of oleoresinosis in grand fir (Abies grandis) differential transcriptional control of monoterpene, sesquiterpene, and diterpene synthase genes in response to wounding. Plant Physiol 116 1497 Stoessl A, Stothers JB, Ward EB (1976) Sesquiterpenoid stress compounds of the solanaceae. Phytochemistry 15 855-872... 

Stoessl A, Stothers JB, Ward EWB (1976) Sesquiterpenoid stress compounds of the... 

Uegaki R, Fujimori T, Kubo S, Kato K (1983) Sesquiterpenoid stress compounds from Nicotiana rustica inoculated with TMV. Phytochemistry 22 1193-1195 Uegaki R, Fujimori T, Kubo S, Kato K (1985) Stress compounds from Nicotiana rustica inoculated with TMV. Phytochemistry 24 2445-2447... 

Uegaki R, Kubo S, Fujimori T (1988) Stress compounds in the leaves of Nicotiana undulata induced by TMV inoculation. Phytochemistry 27 365-368 Usubillaga AN, Meccia G (1987) Steroidal sapogenins from Solanum scorpioideum. J Nat Prod 50 636-641... 

A chemist, chemical or corrosion engineer involved in the oil industry, will certainly appreciate the fact that rubber is an engineering material as molded rubber seals or O rings are used under conditions of strain and stress. Compounding for either of these conditions needs considerably different approaches. The following three basic factors need to be considered ... 

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