Annual Research & Review in Biology

Four fundamental biological functions are responsible for bacterial pathogenicity in a multi-cellular host organism: the adhesive function, the function of invasion and penetration into the cell, the function of evasion of host defense, and the damage function. The action of the first three of them (adhesion, invasion and evasion) is directed to towards establishing an ecological niche in Multi-cellular host, while the aim of the damaging function is destruction of this environment.

Aims: Raw tropical legumes have abundant amounts of tannins and saponins which are usually eliminated with high temperature once they are cooked. These biomolecules may represent new alternatives, to allopathic medicine, in order to prevent the accumulation of free radicals affecting the cells, or to prevent thrombosis in the blood stream respectively. Therefore the aim of this study was to evaluate the antioxidant and antithrombotic activity attributed to tannins and saponins in whole seeds flour (WSF) and fractions resulting in three types of components: endosperm (flour without hulls –Fw/oH-), protein concentrate (PC) and hulls, of two types of tropical legumes Vigna unguiculata (Cowpea) and Mucuna pruriens (Velvet bean). Analysis of nutritional value and also tannins and saponins content was carried out. Finally, antioxidant and antithrombotic activity was also estimated.
Place and Duration of Study: Experiments were carried out in the laboratory of Food Science of the Faculty of Chemical Engineering of the Autonomous University of Yucatán, located in Mérida, Yucatán. México, during 2011-2012.
Study Design: Variables were analyzed with descriptive statistics and using the method of Generalized Linear Model to detect the effect of the type of legume, type of component and their interaction.
Methodology: Analysis of nutritional value and also tannins and saponins content was carried out. Finally, antioxidant (5093 Trolox equivalent units, TEAC) and antithrombotic activity (measurement of the capacity to inhibit the aggregation of blood platelets) was also estimated (n =3).
Results: Type of legume did not affect protein content (p>.05), but there were differences in the content of moisture, fat, ash and carbohydrate (p<.05); different seed fractions exhibited different nutritional profile. Tannin content was greater in M. pruriens (0.63%) compared to V. unguiculata (0.38%) (p<.01); among the components tested, a higher concentration was detected in WSF (1%)(p<.01). The greatest antioxidant activity was observed in V. unguiculata (p<.01) whereas in the fractions, the highest concentration was found in the hulls (5937 TEAC) (p<.01). These values are considered high. Saponin content was higher in V. unguiculata (25.8 mg / g) (p<.01); as far as the components tested, the hulls had a higher content (22.7 mg / g) (p<.01). Antithrombotic activity was similar in both legumes and as far as the components is concern, the most abundant amount was found in the Fw/oH. In all cases, values were found to be low.
Conclusion: V. unguiculata hulls showed high antioxidant activities, which were inversely related to tannin content. Saponin content apparently was not associated with antithrombotic activity since it was found to be low in both legumes.

An analysis of eight physical and chemical parameters was realized to determine the influence of species on the biodiversity of water mites. A total of 292 water mites belonging to 9 species were collected from the two lakes (Tonga and Oubeira), El-mellah lagoon, and Goureate pool from November 2007 to November 2009. Despite this importance, the Hydracarina have not been well investigated or documented in northern Algeria or elsewhere in Africa. To expand current knowledge of the Hydracarina in Algeria, we examined water mites biodiversity and physical and chemical characteristics of mites habitats in 4 locations of the wetland complex in the North-East of Algeria. We found 9 species belonging to 5 families The species dominants (dominance>5%) were Eylais hamata (24%), Piona alpicola (22%), Arrenurus novus (13%), Eylais sp.(12%), Piona nodata (10%), Arrenurus batillifer (10%) and (dominanceË‚5%) were Hydrochoreutes intermedius (4.5%), Diplodontus sp.(3.5%), Hydrachna globosa (3.4%) distributed among our sample sites, and were able to determine significant differences in physical and chemical parameters among the sites as well. This research project can hopefully serve as a model for further studies on the distribution and habitat preferences of African Hydracarina especially in Algeria.

The betel leaf (Tambula patra brint) is extensively cultivated in warm moist parts of India for its leaves; the antifertility properties of the betel plant were studied in both male and female rats. It was suggested that the contraceptive effect of the extract of leaf stalk of piper betel Linn is mainly on the maturation process of spermatozoa in epididymis without influencing hysteric hormonal profiles. The main aim of this study was to evaluate the antifertility efficacy of piper betel Linn leaf stalk extract with reference to some marker enzymes. In this study healthy male albino rats were administered with betel leaf stalk extract, at the dose rate of 150 mg/Kg/ day through oral gavage, for 15 days. The enzymatic changes were observed over control male rats. The observed reduction in Glucose-6-Phosphate dehydrogenase activity in testis, suggests that decreased level of operation of hexose mono phosphate pathway and also mobilization of carbohydrate reserves in to Hexose mono phosphate (HMP) pathway. Increased Succinate dehydrogenase is an indicative of better energy utilization due to the production of intermediates in the tricarboxylic acid cycle. The significant decrease in testicular Glutamate dehydrogenase activities (a biochemical indicator used to assess injury to the mitochondria) may imply reduction in the amount of energy being made available to the sperm cells. The total phosphorylase activity was highly depleted suggesting the overall degradation of the enzyme, possibly for inhibiting glycogenolysis in response to betel leaf stalk extract. The depleted aldolase levels indicate decreased mobilization of glucose in to Embden-Mayeroff pathway in testis. Thus the extract administration does not affect the normal energy metabolism; it affects the sperm energy metabolism. Hence, sperm metabolic processes are disrupted. It also brings the alterations in chemical composition of seminal plasma and prostatic fluid leads to sperm anomalies.

This study investigated the protective and anti-oxidative effects of silymarin on rats treated with MgO NPs. Number of 32 male wistar rats were used in this experiment, assigned to four groups; one, the control group and the three others were treatment groups. The treated groups inclusive of a group receiving 400 ppm Mg NPs, a group received 200 mg/kg silymarin, and a group received silymarin and that dose of Mg NPs. All groups received the treatment peritoneally as long as four weeks uninterruptedly. Post-treatment tissue level of malondialdehyde as well as the activities of catalase, glutathione peroxidase and superoxide dismutase were measured in the liver. The data were analyzed by implementation of one-way ANOVA and Bonferroni tests. In animals treated with MgO NPs, MDA level significantly increased (P=0.000), while a significant decrease was observed in GPX (P=0.000), SOD (P=0.001), and CAT (P=0.008) activities. However, silymarin prevented the effect of them in the group receiving silymarin and MgO NPs significantly and caused an increase in GPX, SOD and CAT activities as well as a decrease in MDA level (P<0.05). As, nanoparticles have harmful effects on the body raised from the generation of reactive oxygen species, this study showed that silymarin, with its antioxidant properties, may decrease free radicals produced by MgO NPs.

Background: Considerable attention is focused on effects of static magnetic field (SMF) and its increasing use in everyday life. Appliances and various equipments are sources of static magnetic fields with awide – range of technical characteristics.
Objective: In this study we investigated the effect of (SMF) (750 G, 1500 G and 3000 G) on testis and epididymis duct in mice.
Materials and Methods: Fifty BALB\C mice were selected and divided in to four groups (Control and 3 experimental), while control was not exposed to SMF, the experimental group was exposed to SMF (750 G, 1500 G and 3000 G) for 30 days. At the end of 30 days, the mice were weighted sacrificed dissected, after then the testis and epididymis were weighted separately and samples from testis and epididymis duct in all groups were taken and processed for light microscopic studies. Fifty microscopic fields from each group were randomly selected. The diameters and the height of epithelial cells of seminiferous tubules and epididymis duct in 4 group were measured and compared using statistical methods.
Results: The data showed that the weight of testiclesin SMF groups (750 G and 1500 G) significantly reduced compared to the control group (P< 0.05) and the weight of epididymis insignificantly reduced. The weight of testicles and epididymisin the experimental group (3000 G) insignificantly increased compared to control group (P< 0.05). The diameter of epithelial cell of seminiferous tubules and ductus epididymis in experimental group (750 G and 1500 G) significantly decreased compared to the control group (P< 0.05) and insignificantly increased in experimental group (3000 G). The height of epithelial cell of seminiferous tubules and ductus epididymis in the experimental groups (750 G and 1500 G) significantly reduced and in the group (3000 G) significantly increased, compared to control group (P< 0.05).
Conclusion: It could be concluded that the exposure to SMF leads to detrimental effects on male reproductive system in mice as seen by adecrease in diameter of reproductive ducts, the height of epithelial cells and weight of testis and epididymis.

Field study was conducted during the rainy seasons (July-November) of 2007, 2008, 2009 and 2010 at the Research Farm of the International Institute of Tropical Agriculture (IITA) Minjibir, Kano State, Nigeria; to compare responses of six cowpea varieties to tillage. The treatments consisted of tillage systems (zero tillage, flat tillage and ridge tillage) as the main plot and cowpea varieties (IT89KD-391, IT90K-277-2, IT97K-461-4, IT97K-499-35, IT98K-131-2, and IT98K-506-1) as the sub-plot. The treatments were arranged as split plot laid out in a randomized complete block design with four replications.
Zero tillage was significantly superior in influencing days to maturity, canopy height, intercepted photosynthetic active radiation (IPAR) and leaf area index but not total dry matter and grain yield of cowpea. A positive and significant association was recorded for days to physiological maturity and canopy height across the tillage systems with a correlation coefficient of ≤ 40% for days to maturity and ≥50% for canopy height. Though flat tillage showed a positive correlation with intercepted photosynthetic active radiation (IPAR) and leaf area (LAI), but this association was not significant. However, ridge tillage showed a positive and significant correlation with IPAR and LAI (r =0.378*** and 0.384***). All the tillage systems showed a high and significant positive correlation with cowpea dry matter and fodder yield (r= 0.54*** to 0.77***). Across varieties, grain yield was better with flat tillage than zero and ridge tillage systems, with 10% yield advantage over the two. Zero and ridge tillage were similar in their effects on grain yield. Except for IPAR, LAI and total dry matter (TDM), the interaction effect of cowpea varieties and tillage systems was significant. Our result point to the fact that extensive soil tillage (especially, conventional tillage) may not be necessary for cowpea production in this agro-ecology with a high percentage of sand and a sandy loam as soil textural class. Following our result, we may recommended varieties for the different tillage systems as follows: IT98K-131-2, IT97K-461-4, IT90K-277-2, IT98K-506-1 (grain) and IT89KD-391/IT97K-461-4 (best for fodder) for zero tillage system; IT90K-277-2, IT97K-499-35, IT98K-131-2 and IT98K-506-1(grain) and IT89KD-391/IT97K-499-35 (best for fodder) for flat-tillage; IT98K-131-2, IT90K-277-2, IT98K-506-1 and IT97K-464-4(grain) and IT90K-277-2/ IT89KD-391 (best for fodder) for ridge tillage).

The diamondback moth (DBM), Plutella xylostella (L.), is recognized as a widely distributed destructive insect pest of Brassicaceae. The frequency and severity of P. xylostella outbreaks has increased in recent years, due to climate changes, high production of host plants (vegetable and oilseed Brassica crops), genetic flexibility of the pest that enables it to develop resistance to almost all known insecticides and establish quickly and easily in new environment. All life stages of P. xylostella are attacked by natural enemies but Diadegma insulare (Cresson) is one of the principal, effective and efficient larval parasitoids in North America. In this review, we synthesize published information on the primary aspects of P. xylostella origin, dispersal, migration, biology, and host plants and mainly focus on evolutionary ecology of bitrophic and tritrophic interactions among P. xylostella, its host plants and natural enemies.

Saponins are secondary metabolites with high molecular weight. They present in a wide range of plant species and are distributed throughout the bark, leaves, stems, roots and even flowers. Saponins are bitter in taste and in recent years, they have received considerable attention because of their various biological activities including hepatoprotective, anti-ulcer, anti-tumor, antimicrobial, adjuvant and anti-inflammatory activities. Saponins are composed of a lipid soluble aglycone consisting of either a sterol or more commonly a triterpenoid and water soluble sugar residues, due to their amphiphilic nature, they are highly surface active and their biological activities are related to their chemical structures. Both steroidal and triterpenoids saponins show detergent properties. The aim of the present article is to review the saponin and methods of evaluation and also, their application based on the recent studies.

Our review confirms that stem density is affected by seed factors, seedbed conditions and planting methods. Physiologically old seed tubers develop into a ‘weak’ stem density. A loose friable soil that is warm and moist increases sprout emergence leading to a high stem number per hill. This high stem density can be achieved through the use of large seed tubers at planting. The greater the stem densities the higher the yield since more tubers are obtained per plant. An increase in inter stem competition associated with high stem desnity results in a decrease in harvestable tuber weight and size. However, our findings were inconclusive on the influence of varietal differences and planting depth on stem density. The influence of stem density on tuber specific gravity is also yet to be fully understood. We reiterate that producers for ware consumption should aim for low stem populations per hill while conventional seed producer are encouraged to take advantage of higher stem densities.