Effect of some heterocyclic compounds on human semen composition and biology.

The effect of some heterocyclic compounds on some aspects of human semen metabolism was studied. Caffeine produced stimulation of motility and lactic acid production and an inhibition of fructose utilization and oxygen uptake. Nicotinamide and riboflavin produced stimulation of motility, fructose utilization and oxygen uptake and an inhibition of lactic acid production.     

Isolation of Trichoderma and Evaluation of their Antagonistic Potential against Alternaria porri

Nine isolates of Trichoderma were collected from Assiut Governorate, Egypt, as leaf surface and endophytic fungi associated with onion flora stalks. Four isolates were identified as Trichoderma harzianum, while five isolates were belonging to Trichoderma longibrachiatum. The antagonistic activity of these isolates against onion purple blotch pathogen Alternaria porri was studied in vitro using dual culture assay. All tested Trichoderma isolates showed mycoparasitic activity and competitive capability against the mycelial growth of A. porri. Mycoparastic activity of Trichoderma was manifested morphologically by the overgrowth upon the mycelial growth of the pathogen and microscopically by production of coiling hyphae around pathogen hyphae. Isolates of T. harzianum exhibited high ability to compete on potato dextrose agar (PDA) medium causing the maximum rate of pathogen inhibition (73.12%), while isolates of T. longibrachiatum showed inhibition rate equalling 70.3%. Chitinase activity of Trichoderma was assayed, and T. harzianum Th‐3013 showed the maximum value contributing 2.69 U/min. Application of T. harzianum Th‐3013 to control purple blotch disease in vivo under greenhouse conditions caused disease reduction up to 52.3 and 79.9% before and after 48 h of pathogen inoculation, respectively, while the fungicide Ridomil Gold Plus caused disease reduction comprising 56.5 and 71.7%, respectively. This study proved that T. harzianum Th‐3013 as a biocontrol agent showed significant reduction in onion purple blotch disease compared with the tested fungicide.     

The putative immunity protein of the Gram-positive bacteria Leuconostoc mesenteroides is preferentially located in the cytoplasm compartment

Abstract Immunity proteins are thought to protect bacteriocin-producing bacterial strains against the bactericidal effects of their own bacteriocin. The immunity protein which protects the lactic acid bacterium Leuconostoc mesenteroides against mesentericin Y105³⁷ bacteriocin was detected and localized by immunofluorescence and electron microscopy, using antibodies directed against the C-terminal end of the predicted immunity protein. The antibodies recognized the immunity proteins of various strains of Leuconostoc , including Leuconostoc mesenteroides and Leuconostoc gelidum . This study demonstrated that immunity proteins produced by Leuconostoc mesenteroides accumulated in the cytoplasmic compartment of the bacteria. This is in contrast with other known immunity proteins, such as the colicin immunity proteins, which are integral membrane proteins possessing three to four transmembrane domains.     

Studies on the freshwater algae of the Sudan III,vertical distribution of Melosira granulata (Ehren.) Ralfs. in the White Nile,with reference to certain environmental variables

The variations in the number of Melosira granulata in the vertical column of the White Nile was followed for 18 months during the years 1969–71, together with diurnal changes. The monthly as well as the diurnal fluctuations in the levels of certain physical and chemical parameters were simultaneously considered. The counts indicated noticeable progressive decreases from surface to the bottom of the river. Pronounced stratification of the alga was evident during certain months but without apparent correlation with any of the factors analysed.     

Biogeographical relations of a hyperarid desert flora in eastern Egypt

The floristic composition and geographical elements of the study area were analysed resulted in 328 species representing 206 genera in 55 families. This study confirmed the record of fourteen species, mostly weeds, which can be considered as new additions to the flora of the study area. Therophytes were the dominant life form, while mono‐ and bi‐regional Saharo‐Sindian geoelements were the most represented. Ten species showed dominancy with their Q‐values ranged between 0.802 and 0.2, where Zilla spinosa and Zygophyllum coccineum were of common occurrence. Application of cluster analysis and DCA ordination techniques produced four major floristic groups (A–D) comprising seven subgroups. The correlation coefficients (r) between the different subgroups revealed high significant correlations (P = 0.01) between floristic group (B) and subgroup (C₂) and between subgroups (D₁) and (D₂). Significant correlations (P = 0.05) occurred between subgroup (D₁) and both of (A₁) and (C₂). Comparing the floristic similarities between this investigation and other relevant studies were presented and discussed. On the other hand, the low similarity index between the study area and Sinai may be attributed to the geographical position of both deserts where Sinai desert is part of the Irano‐Turanian region, while the Eastern Desert is a part of the Saharo‐Sindian region.     

Antioxidant status and ultrastructural defects in the ovaries of red palm weevils (Rhynchophorus ferrugineus) intoxicated with spinosad

Red palm weevil, Rhynchophorus ferrugineus, destroys palms almost all over the world, especially in the Middle East, where dates are a strategic crop in arid places. In view of the urgent need to combat this destructive pest, effective pesticides with high environmental safety should be sought. Spinosad is a pesticide of bacterial origin that is presumed to have a high degree of environmental safety and is effective in combating a wide range of insect pests. In this study, the efficacy of spinosad was evaluated in females of R. ferrugineus. The lethal concentration for 50% of the treated females was calculated at 44.3 ppm. The effects of spinosad concentrations of 10, 50 and 200 ppm on the activity of catalase (CAT), glutathione S‐transferase (GST) and superoxide dismutase (SOD) in the ovaries were assessed. In addition, the pathological effects of these concentrations were documented on the ultrastructure of the follicle cells and ooplasm. The results showed a significant increase in CAT activity only in response to treatment with 200 ppm. Treating the females with different spinosad concentrations resulted in varying intensity changes in cell organelles, where the most pronounced sign of programmed cell death was at the concentration 200 ppm. This study demonstrates the possibility of using spinosad as an insecticide against females of R. ferrugineus.     

Inhibition of tyrosine protein kinases by halomethyl ketones

A chloromethyl ketone derivative of lactic acid was shown to inhibit protein phosphorylation in plasma membranes of Ehrlich ascites tumor cells [Johnson, H. J., Zimniak, A., & Racker, E. (1982) Biochemistry 21, 2984-2989]. We now show that this inhibitor as well as three halomethyl ketone derivatives of amino acids and peptides specifically inhibits tyrosine protein kinase activity in intact plasma membranes and Triton extracts of plasma membrane of A-431 tumor cells. The most effective inhibitor is a bromomethyl ketone derivative of leucine that inhibits the phosphorylation of a protein that migrates to the same position as the EGF receptor in sodium dodecyl sulfate-polyacrylamide gel electrophoresis. Inhibition of phosphorylation took place in the presence or absence of added EGF, and the inhibitor did not interfere with the binding of EGF to the receptor nor with the dephosphorylation of the EGF-stimulated phosphoprotein. EGF-dependent phosphorylation in a Triton extract of plasma membranes from normal placenta was considerably less sensitive to the bromomethyl ketone derivative of leucine. The tyrosine protein kinase activity of the transformation gene product of Fujinami virus was particularly sensitive to the bromomethyl ketone derivative of leucine, while the src gene product of Rous sarcoma virus was comparatively less sensitive. The bromomethyl ketone inhibitor interfered with the phosphorylation of the EGF receptor by [gamma-32P]-8-azido-ATP but much less with the light-sensitive binding. This observation and the lack of interference with EGF binding suggest that the inhibitor interacts with the protein kinase portion of the receptor complex.     

Evaluation of growth and nutritional value of Brassica microgreens grown under red,blue and green LEDs combinations

Microgreens are rich functional crops with valuable nutritional elements that have health benefits when used as food supplements. Growth characterization, nutritional composition profile of 21 varieties representing five species of the Brassica genus as microgreens were assessed under light-emitting diodes (LEDs) conditions. Microgreens were grown under four different LEDs ratios (%); red:blue 80:20 and 20:80 (R₈₀:B₂₀ and R₂₀:B₈₀), or red:green:blue 70:10:20 and 20:10:70 (R₇₀:G₁₀:B₂₀ and R₂₀:G₁₀:B₇₀). Results indicated that supplemental lighting with green LEDs (R₇₀:G₁₀:B₂₀) enhanced vegetative growth and morphology, while blue LEDs (R₂₀:B₈₀) increased the mineral and vitamin contents. Interestingly, by linking the nutritional content with the growth yield to define the optimal LEDs setup, we found that the best lighting to promote the microgreen growth was the green LEDs combination (R₇₀:G₁₀:B₂₀). Remarkably, under the green LEDs combination (R₇₀:G₁₀:B₂₀) conditions, the microgreens of Kohlrabi purple, Cabbage red, Broccoli, Kale Tucsan, Komatsuna red, Tatsoi and Cabbage green, which can benefit human health in conditions with limited food, had the highest growth and nutritional content.     

The freshwater planarian Dugesia sicula Lepori, 1948 (Platyhelminthes, Tricladida) in Tunisia: ecology, karyology, and morphology

A study was carried out on freshwater planarians of the genus Dugesia from three localities in northern Tunisia: Joumine, Chiba, and Lebna. The three populations are fissiparous under field conditions and do not possess reproductive organs, except for some cases of hyperplastic ovaries in the Joumine population. After five months of breeding under laboratory conditions, with water temparature between 18 and 25?°C and under short photoperiod, 8.33 to 26% of specimens from the Joumine stream became sexualized, together with considerable increase of body length and width. For the other two populations the sexualization rate was very small. Extended period of darkness apparently played a positive role in this sexualization. The phenomenon of sexualization is discussed in the context of reproductive strategies. Histological and karyological studies of the sexualized animals allowed identification of these usually fissiparous planarians as representatives of Dugesia sicula Lepori, 1948. The species is here reported for the first time from Tunisia. The populations are restricted to permanent water basins resulting from the construction of dams in large rivers.