The objective of this study was to prepare acceptable carbopol gels and to evaluate
the factors influencing the spreadability and release properties of a model hydrophilic
compound (caffeine). Results were analyzed statistically using student t-tes
t. The gels
were transparent at 1 and at 2% caffeine (with alcohol). Spreadability was decreased when
carbopol was increased and when caffeine quantity was changed (except at 2% carbopol).
Spreadability was affected statistically with change of cosolvent. Released caffeine
quantity (%) was increased with decreasing of carbopol quantity and increasing of caffeine
quantity introduced in the formula. Total caffeine quantity (%) was decreased with alcohol
presence. Caffeine release followed Higuchi pattern, e.g. diffusion was the principal
mechanism of caffeine release from these formulas.
Nineteen locally selected potato lines were screened for water stress
tolerance by measuring the growth parameters in vitro. The stress was achieved
by adding 4% of sorbitol to the growth medium. Plant height and diameter,
leaf area, number, lengt
h and diameter of roots and plant fresh and dry weight
were measured. The results showed a difference in the response of the studied
lines to water stress, cluster analysis, based on the sum of all growth
parameters relative values of the lines showed that the lines were divided into
three groups according to water stress tolerance: The tolerant group, the
moderate tolerant group and the sensitive group. The results indicated the
possibility to use the in vitro method to screen the potato lines for water stress
tolerance.
This research was conducated on Ceratonia siliqua L. in vitro to study the effect of
some growth regulators in both multiplication and rooting stage. And determine the best
concentrations wich lead the highest rate of multiplication (interms of number of shoots
and length), and the best rooting (interms of percentage of rooting, number of roots and
length).
