الفهرس 
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Abstract
ABSTRACT
Mona Shaban Abd EL Aal: Effect of Irradiation on Internal
Structure and Active Ingredient of Echinacea purpurea. Unpublished
Ph.D. Thesis, Department of Agriculture Botany, Faculty of
Agriculture, Ain Shams University, 2016.
Series of experiments were carried out successively during the
years of 2013 to 2015. The effects of UV-C, UV-B and gamma radiation
on the anatomical structure of Echinacea seedling and biochemical
components of callus and cell suspension were investigated. The results
indicated that incubation periods and UV-C treatments were effective on
growth parameters and chemical components. It is obvious that growth
parameters & guaiacol peroxidase (G-POD) activity in callus and cell
suspension cultures in addition to caffeic acid derivatives &
phenylalanine ammonia lyase (PAL) in cell suspension and nonenzymatic
antioxidant activity in callus culture increased by increasing
incubation period and the reverse was true for caffeic acid in callus. On
the other hand, incubation period 48 hours was the most influence in total
phenols content and PAL activity of callus while, incubation period 72
hours achieved the highest increment in total phenols content and
antioxidant activity in cell suspension culture.
All UV-C treatments led to an increment in caffeic acid &
antioxidant activity of callus cells and growth parameters, total phenols
content & antioxidant activity of cell suspension and the reverse was true
for G-POD activity in callus and cell suspension cultures comparing to
the control. On the other side, the two exposure times 30 & 60 min led to
increasing callus growth and total phenols while exposure time 60 min
detected an increment in caffeic acid of cell suspension and PAL activity
in the two types of cultures as compared to the control.
UV-B led to an increment of all growth parameters and
antioxidant activity in callus and cell suspension and caffeic acid
derivatives in cell suspension by increasing incubation period and the
reverse was true for G-POD activity in cell suspension and PAL activity
in both types of cultures. While, incubation period 2 weeks was more
effective in caffeic acid, total phenols and G-POD activity in callus cells
and incubation period one week only for total phenols in cell suspension.
Apart from the effect of second exposure time (4 hours) on fresh
weight and growth index of cell suspension, UV-B led to an increment of
all growth parameters in the two types of cultures and G-POD activity in
callus cells and reverse was true for G-POD activity in cell suspension &
PAL activity in callus cells comparing to the control. On the other side,
the two exposure times 2 & 4 hours increased antioxidant activity in the
two types of cultures. Meanwhile, exposure time 2 hours led to increase
caffeic acid and total phenols in callus cells, while, the maximum increase
in caffeic acid, total phenols and PAL activity in cell suspension was
achieved by 4 hours exposure time. Likewise, using 2 UV-B lamps for 2
hours was the most effective in creating more biochemical components.
Significant increase in fresh weight and growth index of irradiated
callus was detected with the doses 40 and 50 Gy of gamma. On the
contrary, the dry weight decreased significantly in all gamma treatments
against the control, in addition to caffeic acid derivatives, total phenols
and antioxidant activity. The reverse was true for enzymes activity GPOD
& PAL and irradiated callus with 20 Gy recorded the highest
activity values of G-POD and PAL. Also, gamma caused changes in the
internal structure of seedling such as harmful of the shoot apex. Also, it
affected in the cotyledonary leaf whereas the leaf shape changed and
decreased in thickness. The hypocotyl showed decreasing in the cells
growth, alteration in the shape and damage or necrosis of its epidermal
cells and perception of large size nuclei. Changes in the size and density
of the chloroplasts in foliage leaf mesophyll. Decreasing in number of
xylem and phloem vessels in the secondary vascular tissues.
Key wards: Echinacea purpurea, UV-C, UV-B, gamma, in vitro, caffeic
acid derivatives, enzymes