The detailed macro- and micromorphological characters of the leaf, stem and root of Juglans nigra Linn. (Black Walnut) cultivated in Egypt have been studied in order to find out the diagnostic features which can help in the identuification of the plant in both entire and powdered forms.

From the methanolic extract of the leaves of Juglans nigra L. (Black Walnut) Family Juglandaceae (Walnut family), kaempferol-3-O-ß-glucoside quercetin-3-O-ß-glucoside and quercetin-3-O- ß-glucoside-6``-ethyl ester were isolated for the first time from the family Juglandaceae, in addition to stigmasterol-3-O-ß-glucoside. The structures were established on the basis of UV, MS and NMR (1H, 13C and DEPT) spectroscopic data. Moreover, the hypotensive and toxicological studies were done.

From the methanolic extract of the leaves of Juglans nigra L. (Black Walnut) Family Juglandaceae (Walnut family), kaempferol-3-O-ß-glucoside quercetin-3-O-ß-glucoside and quercetin-3-O- ß-glucoside-6``-ethyl ester were isolated for the first time from the family Juglandaceae, in addition to stigmasterol-3-O-ß-glucoside. The structures were established on the basis of UV, MS and NMR (1H, 13C and DEPT) spectroscopic data. Moreover, the hypotensive and toxicological studies were done.

From the methanolic extract of the leaves of Juglans nigra L. (Black Walnut) Family Juglandaceae (Walnut family), kaempferol-3-O-ß-glucoside quercetin-3-O-ß-glucoside and quercetin-3-O- ß-glucoside-6``-ethyl ester were isolated for the first time from the family Juglandaceae, in addition to stigmasterol-3-O-ß-glucoside. The structures were established on the basis of UV, MS and NMR (1H, 13C and DEPT) spectroscopic data. Moreover, the hypotensive and toxicological studies were done.

Destruxin B and sirodesmin PL are phytotoxins produced by the phytopathogenic fungi Alternaria brassicae (Berk.) Sacc. and Leptosphaeria maculans (asexual stage Phoma lingam), respectively. The molecular interaction of destruxin B and sirodesmin PL with cruciferous and cereal species was investigated using HPLC-ESI-MS(n). It was determined that crucifers transformed destruxin B to hydroxydestruxin B, but sirodesmin PL was not transformed. Overall, the results suggest that the five cruciferous species Arabidopsis thaliana, Thellungiella salsuginea, Erucastrum gallicum, Brassica rapa and Brassica napus are likely to produce a destruxin B detoxifying enzyme (destruxin B hydroxylase), similar to other cruciferous species reported previously. In addition, HPLC analyses and quantification of the phytoalexins elicited in each cruciferous species by these phytotoxins indicates that sirodesmin PL elicits a larger number of phytoalexins than destruxin B. Interestingly, transformation of destruxin B appears to occur also in the cereals Avena sativa and Triticum aestivum; however, the various destruxin metabolites detected in these cereals suggest that these reactions are non-specific enzymatic transformations, contrary to those observed in crucifers, where only a main transformation pathway is detectable. None of the toxins appear to elicit production of metabolites in either A. sativa or T. aestivum.

The colon is being viewed as a promising site of drug delivery owing to its long transit time (up to 78 hrs), which is likely to increase the time available for drug absorption. Progesterone (PG) has a short elimination half-life (~19-95 min) and undergoes extensive first-pass hepatic metabolism which results in very low oral bioavailability (~25%). The aim of this work was to study the feasibility of preparing PG-loaded colon-targeted microparticles (MP's) to overcome the shortcomings associated with the oral administration of PG. MP's were prepared by the modified ionotropic gelation technique using sodium carboxymethylcellulose (NaCMC)/pectin mixture as a biodegradable matrix, zinc acetate and aluminum sulfate as cross-linkers. A 24 full factorial design was carried out to optimize the experimental conditions with the investigated factors being: polymer concentration (X¬1), drug concentration (X2), Zn(CH3COO)2 concentration (X3) and Al2(SO4)3 concentration (X4). The prepared MP's were investigated under conditions mimicking mouth-to-colon transit and the effect of the afore-mentioned factors on the release and surface characteristics of MP's has been studied. The results obtained implied that, regardless of the concentration of cross-linking agents, the polymer and drug concentrations exhibited the greatest influence on the drug entrapment efficiency (EE), which decreased as the drug concentration decreased from 1 to 0.5% w/v (95.13% and 83.88% respectively) and as the polymer concentration increased from 1.25 to 1.5% w/v (107.35% and 95.13% respectively). On the other hand, MP's prepared with 1% drug showed a significantly slower release rate than those prepared with 0.5% drug as indicated by the values of Mean Dissolution Time (MDT) & the release rate constant(k). This study confirms the viability of the prepared microparticles as a colon-targeted drug delivery system.

The colon is being viewed as a promising site of drug delivery owing to its long transit time (up to 78 hrs), which is likely to increase the time available for drug absorption. Progesterone (PG) has a short elimination half-life (~19-95 min) and undergoes extensive first-pass hepatic metabolism which results in very low oral bioavailability (~25%). The aim of this work was to study the feasibility of preparing PG-loaded colon-targeted microparticles (MP's) to overcome the shortcomings associated with the oral administration of PG. MP's were prepared by the modified ionotropic gelation technique using sodium carboxymethylcellulose (NaCMC)/pectin mixture as a biodegradable matrix, zinc acetate and aluminum sulfate as cross-linkers. A 24 full factorial design was carried out to optimize the experimental conditions with the investigated factors being: polymer concentration (X¬1), drug concentration (X2), Zn(CH3COO)2 concentration (X3) and Al2(SO4)3 concentration (X4). The prepared MP's were investigated under conditions mimicking mouth-to-colon transit and the effect of the afore-mentioned factors on the release and surface characteristics of MP's has been studied. The results obtained implied that, regardless of the concentration of cross-linking agents, the polymer and drug concentrations exhibited the greatest influence on the drug entrapment efficiency (EE), which decreased as the drug concentration decreased from 1 to 0.5% w/v (95.13% and 83.88% respectively) and as the polymer concentration increased from 1.25 to 1.5% w/v (107.35% and 95.13% respectively). On the other hand, MP's prepared with 1% drug showed a significantly slower release rate than those prepared with 0.5% drug as indicated by the values of Mean Dissolution Time (MDT) & the release rate constant(k). This study confirms the viability of the prepared microparticles as a colon-targeted drug delivery system.

The colon is being viewed as a promising site of drug delivery owing to its long transit time (up to 78 hrs), which is likely to increase the time available for drug absorption. Progesterone (PG) has a short elimination half-life (~19-95 min) and undergoes extensive first-pass hepatic metabolism which results in very low oral bioavailability (~25%). The aim of this work was to study the feasibility of preparing PG-loaded colon-targeted microparticles (MP's) to overcome the shortcomings associated with the oral administration of PG. MP's were prepared by the modified ionotropic gelation technique using sodium carboxymethylcellulose (NaCMC)/pectin mixture as a biodegradable matrix, zinc acetate and aluminum sulfate as cross-linkers. A 24 full factorial design was carried out to optimize the experimental conditions with the investigated factors being: polymer concentration (X¬1), drug concentration (X2), Zn(CH3COO)2 concentration (X3) and Al2(SO4)3 concentration (X4). The prepared MP's were investigated under conditions mimicking mouth-to-colon transit and the effect of the afore-mentioned factors on the release and surface characteristics of MP's has been studied. The results obtained implied that, regardless of the concentration of cross-linking agents, the polymer and drug concentrations exhibited the greatest influence on the drug entrapment efficiency (EE), which decreased as the drug concentration decreased from 1 to 0.5% w/v (95.13% and 83.88% respectively) and as the polymer concentration increased from 1.25 to 1.5% w/v (107.35% and 95.13% respectively). On the other hand, MP's prepared with 1% drug showed a significantly slower release rate than those prepared with 0.5% drug as indicated by the values of Mean Dissolution Time (MDT) & the release rate constant(k). This study confirms the viability of the prepared microparticles as a colon-targeted drug delivery system.

The colon is being viewed as a promising site of drug delivery owing to its long transit time (up to 78 hrs), which is likely to increase the time available for drug absorption. Progesterone (PG) has a short elimination half-life (~19-95 min) and undergoes extensive first-pass hepatic metabolism which results in very low oral bioavailability (~25%). The aim of this work was to study the feasibility of preparing PG-loaded colon-targeted microparticles (MP's) to overcome the shortcomings associated with the oral administration of PG. MP's were prepared by the modified ionotropic gelation technique using sodium carboxymethylcellulose (NaCMC)/pectin mixture as a biodegradable matrix, zinc acetate and aluminum sulfate as cross-linkers. A 24 full factorial design was carried out to optimize the experimental conditions with the investigated factors being: polymer concentration (X¬1), drug concentration (X2), Zn(CH3COO)2 concentration (X3) and Al2(SO4)3 concentration (X4). The prepared MP's were investigated under conditions mimicking mouth-to-colon transit and the effect of the afore-mentioned factors on the release and surface characteristics of MP's has been studied. The results obtained implied that, regardless of the concentration of cross-linking agents, the polymer and drug concentrations exhibited the greatest influence on the drug entrapment efficiency (EE), which decreased as the drug concentration decreased from 1 to 0.5% w/v (95.13% and 83.88% respectively) and as the polymer concentration increased from 1.25 to 1.5% w/v (107.35% and 95.13% respectively). On the other hand, MP's prepared with 1% drug showed a significantly slower release rate than those prepared with 0.5% drug as indicated by the values of Mean Dissolution Time (MDT) & the release rate constant(k). This study confirms the viability of the prepared microparticles as a colon-targeted drug delivery system.

The colon is being viewed as a promising site of drug delivery owing to its long transit time (up to 78 hrs), which is likely to increase the time available for drug absorption. Progesterone (PG) has a short elimination half-life (~19-95 min) and undergoes extensive first-pass hepatic metabolism which results in very low oral bioavailability (~25%). The aim of this work was to study the feasibility of preparing PG-loaded colon-targeted microparticles (MP's) to overcome the shortcomings associated with the oral administration of PG. MP's were prepared by the modified ionotropic gelation technique using sodium carboxymethylcellulose (NaCMC)/pectin mixture as a biodegradable matrix, zinc acetate and aluminum sulfate as cross-linkers. A 24 full factorial design was carried out to optimize the experimental conditions with the investigated factors being: polymer concentration (X¬1), drug concentration (X2), Zn(CH3COO)2 concentration (X3) and Al2(SO4)3 concentration (X4). The prepared MP's were investigated under conditions mimicking mouth-to-colon transit and the effect of the afore-mentioned factors on the release and surface characteristics of MP's has been studied. The results obtained implied that, regardless of the concentration of cross-linking agents, the polymer and drug concentrations exhibited the greatest influence on the drug entrapment efficiency (EE), which decreased as the drug concentration decreased from 1 to 0.5% w/v (95.13% and 83.88% respectively) and as the polymer concentration increased from 1.25 to 1.5% w/v (107.35% and 95.13% respectively). On the other hand, MP's prepared with 1% drug showed a significantly slower release rate than those prepared with 0.5% drug as indicated by the values of Mean Dissolution Time (MDT) & the release rate constant(k). This study confirms the viability of the prepared microparticles as a colon-targeted drug delivery system.