الفهرس 
INTRODUCTIONOnly 14 pages are availabe for public view
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Abstract
Medicinal plants are important for pharmacological research and drug development, not only when plant constituents are used directly as therapeutic agents, but also as starting materials for the synthesis of drugs or as models for pharmacologically active compounds. A.visnaga is one of the traditional medicinal plants used for many medicinal
purposes. Searching for suitable bioregulators such as some aromatic amino acids (tyrosine and phenylalanine) and phenolic substances (salicylic acid, trans-cinnamic acid &
benzoic acid) which might enhance the growth and the productivity of A.visnaga plants during vegetative,
flowering and fruiting stages is the objective of this investigation. Moreover, determination of the proper
concentration of bioregulators and the suitable time for harvesting high yield and more active substances in the
leaves and fruits of A.visnaga is another objective of this study.
Thus, the main experimental results can be summarized in the following:
1- Foliar application of A.visnaga plants with different concentrations of either amino acids or phenolic compounds resulted in an increase in vegetative growth parameters in terms of plant height, number of branches,
number of umbels, fresh and dry shoot weights. Such increments in the vegetative growth parameters was
more pronounced with 20 mg L-1 benzoic acid treatment at the vegetative, flowering, early fruiting and fruiting
stages, respectively.
2- Application of either aromatic amino acids or phenolic compounds increased the photosynthetic pigments content (chlorophyll a and b) concomitant with
increases in soluble, insoluble carbohydrates, total carbohydrates, soluble, insoluble and total proteins
contents particularly in A.visnaga plants exposed to 20 mg L-1 benzoic acid.
3- GC–MS analysis revealed that the relative levels of amino acids were increased, decreased or disappeared in
A.visnaga leaves of plants exposed to either amino acids or phenolic compounds compared with the untreated
control plants. Seventeen free amino acids can be seen in the A.visnaga shoots exposed to the various treatments of phenolic compounds and amino acids (Threonine, Serine, Glutamic acid, Glycine, Alanine, Cystine, Valine, Methionine, Isoleucine, Leucine Tyrosine, Phenylalanine, Histidine, Lysine, Arginine and Proline). The main amino acids detected in the A.visnaga shoots exposed to the various investigated
treatments are aspartic acid, proline, glutamic acid, tyrosine, phenylalanine and alanine.
4- Foliar application of phenols and amino acids at all investigated concentrations resulted in greater increases in the levels of growth promoters including auxins, GA3
and cytokinins in A.visnaga plants compared to control untreated one. The maximum levels of growth promoters was attained in A.visnaga plants exposed to
foliar application of phenols particularly benzoic acid compared to those related with amino acids.
5- The levels of ABA accumulation were relatively reduced in A.visnaga shoots treated with either amino acids or
phenolic compounds. The untreated of Ammi visnaga plants exhibited the highest level of ABA.
6-The exposure of A.visnaga plants to various concentrations of either amino acids or phenolic compounds increased the levels of some elements such
as Fe, Mg and Cu particularly in A.visnaga shoots treated with 20 mg L-1 benzoic acid.
7- The activities of CAT, SOD, POX and PAL enzymes were markedly increased after foliar application of either amino acids or phenolic compounds. The greatest values of CAT, SOD and POX were assayed in A.visnaga shoots exposed to 20 mg L-1 benzoic acid.
However, the highest values of PAL were measured at 20 mg L-1salicylic acid.
8- Both amino acids and phenolic compounds treatments increased DNA and RNA content in A.visnaga shoots
throughout the experimental period. Such increases in the nucleic acids were more pronounced in 20 mg L-1
benzoic acid treated plants.
9- Treatments of either amino acids or phenolic compounds increased the accumulation of the total free phenols and flavonoids especially at 20 mg L-1 salicylic acid.
10- The main phenolic acids detected by the HPLC analysis in the A.visnaga shoots exposed to the various investigated treatments were coumaric acid, P- hydroxy benzoic acid, trans- cinnamic acid, cinnamic acid, ferulic acid, protocaticuic, gallic acid, syringic acid and caffic acid. Generally, the foliar applications of phenolic acids stimulate the accumulation of ferulic, cinnamic, Phydroxy benzoic and syringic acids compared with those of the control and the amino acid treated plants.
The content of coumaric acid, the most common phenolic acid in A.visnaga plants was markedly increased after the application of various concentrations
of either amino acids or phenolic acids. The greatest increment in the content of coumaric acid has been
assayed at 200 mg L-1 phenylalanine.
11- Both amino acids and phenolic compounds treatments significantly increased the total chromones in A.visnaga leaves and fruits. Foliar application of 20 mg L- 1 benzoic acid attained the highest levels of chromones.
12- Application of either amino acids or phenolic compounds markedly increased the oil percentage and oil yield in A.visnaga fruits. The greatest increase in the oil content was determined in A.visnaga fruits treated
with 20 mg L-1benzoic acid.
13- It is obvious that foliar application of different concentrations of phenols and amino acids achieved
significant reductions in the total antioxidant activity of A.visnaga fruits as compared with the untreated control plants. The lowest percentage of the total antioxidant capacity was assayed in A.visnaga fruits yielded from
Plants treated with 20 mg L-1 benzoic acid.
14- The major constituents of A.visnaga fruits detected by GC-MS analysis are 2, 2-Dimethylbutanoic acid, isobutyl isobutyrate, linalool, thymol and croweacin of essential oils.
15- Moreover, the major class of A.visnaga oil was monoterpene compounds. The highest value of
monoterpene were determined in the A. visnaga fruits of untreated control and the treatments with 50 mg L-1 tyrosine, 200 mg L-1 phenylalanine, 10 mg L-1 benzoic acid, 5 and 20 mg L-1 salicylic acid. However, the highest level of sesquiterpene compounds achieved in
20 mg L-1 treated fruits (5.4%).