Authors:R. Gill, A. Gupta, G. Taggar and Monica Taggar
Crop productivity is greatly influenced by various environmental stresses, of which insect herbivory-induced biotic stress assumes much significance. As a consequence of insect herbivory, a number of plant biochemical processes involved in the tolerance mechanism are affected. Different studies have demonstrated a diverse functional role of various plant oxidative enzymes in protecting plants against biotic stress induced by insect herbivory. Comprehensive profiling of stress-associated plant oxidative enzymes is most relevant to successful molecular breeding of stress-tolerant crop plants. Thus, better understanding of the biochemical basis of plant defense mechanisms is imperative, not only from a basic science perspective, but also for biotechnology-based pest control practice. In this review, we emphasize the potential role of various oxidative enzymes in plant defense against insect herbivory.
Authors:R. Avtar, A. S. Rathi, D. S. Jatasra and U. N. Joshi
phenols and some oxidativeenzymes in cowpea leaves infected with yellow mosaic virus. Acta Phytopathol. Entomol. Hung. 31, 191–197.
Changes in total phenols and some oxidativeenzymes in cowpea leaves infected with yellow mosaic
Joshi, U. N. and Gupta, P. P. (2002): Oxidativeenzymes in cowpea (
L.) in relation to bacterial blight severity. In:Asian Congress of Mycology and Plant Pathology held at University of Mysore, Mysore, India. pp. 1
Authors:M Slavić, M Slavić, M Slavić, I Appiah, I Appiah, I Appiah, A Nikolić-Kokić, A Nikolić-Kokić, A Nikolić-Kokić, R Radojičić, R Radojičić, R Radojičić, DR Jones, DR Jones, DR Jones, MB Spasić, MB Spasić, MB Spasić, S Milovanović, S Milovanović, S Milovanović, D Blagojević, D Blagojević and D Blagojević
interactions between nitric oxide donors, reactive oxygen species and
anti-oxidative defence enzymes led us to determine the activities of
anti-oxidative defence enzymes in isolated uterine smooth muscle before and
after spontaneous rhythmic activity ex vivo. For our experiments we
used isolated uteri from female Wistar rats. Our results showed an increase
in total superoxide dismutase (SOD) and Mn SOD activities in uterine smooth
muscle after spontaneous contractions when compared with non-exercised
uterine smooth muscle. The activity of catalase (CAT) and glutathione
preoxidase (GSH-Px) were also increased. No statistically significant changes
in the activities of glutathione reductase (GR) and CuZn SOD were found. It
is known that an organism's anti-oxidative defence system (guarding against
excessive reactive oxygen species generation) requires balanced increments in
its individual anti-oxidative enzyme activities rather than increases in the
activity of only some enzymes without increases in others. Thus, we may
conclude that some adaptive responses are found in exercised uterine smooth
muscle but are not complete. Therefore, our results indicate that changes in
anti-oxidative enzyme activities may influence the results of the examination
of substances ex vivo.
Authors:Tamás Hofmann, Levente Albert, Tamás Rétfalvi, Eszter Visi-Rajczi and Gábor Brolly
The factors affecting the economically and sylviculturally disadvantageous formation of red heartwoord in beech are only partly understood. It has already been proved that at the color boundary of the red heart the total phenol concentration decreases sharply whereas the activity of oxidative enzymes (POD, PPO) increases substantially. The concentrations of (+)-catechin and (−)-epicatechin fall drastically and the five taxifolin and quercetin glycosides undergo hydrolysis. It is unclear, however, what role the flavonoids present at the boundary ((+)-catechin, (−)-epicatechin, taxifolin, and quercetin) have in the formation of the red chromophores of the heartwood. Understanding the transformation of the precursors and analysis of the products could result an enhanced utilization of redheartwood timber and better understanding of the physiology of red heartwood formation. In this work the role of catechins has been investigated by in-vitro transformation of (+)-catechin and (−)-epicatechin by extracts of beech wood enzymes. Thin-layer chromatography with scanning densitometry and acquisition of the products’ UV-visible reflection spectra proved suitable for monitoring the reactions and analyzing the products. Result have shown that rapid oxidation and oligomerization of the catechins is caused by beech enzyme extract. In-vitro products have also been compared with the chromophores of beech red heartwood. Conclusions have been drawn regarding the physiology of red heartwood formation.
The main criterion that determines the quality of durum wheat is the degree of suitability for pasta production (pasta-processing quality). In this regard, pigment content and the quantity of oxidative enzymes of durum wheat play important roles in the quality of pasta. It is now possible to examine these features and specify their effects using recently developed genetic markers and spectrophotometric measurement techniques. In the present study, LOX enzyme activity and pigment content are determined using molecular and biochemical scanning. According to the obtained results, Gediz-75, Gdem-12, Line-19, Zenit, Line-7 and Line-20 were determined as the most suitable lines or varieties for the production of quality pasta with regard to LOX enzyme activity. As for pigment content, Kyle, Zenit, Gdem-12, Gdem-2, TMB-1 and TMB-3 showed the highest potential for the production of yellow pasta. When pigment content and LOX enzyme activity were evaluated together, the potential of the Gediz-75, Gdem-12 and Zenit durum wheat varieties and lines to produce yellow pasta products was shown to be very high.