Antimicrobial Property of 2-Hydroxypropane-1,2,3-Tricarboxylic Acid Isolated from Citrus microcarpa Extract

This article described antimicrobial property and structure analysis of 2-hydroxypropane-1,2,3-tricarboxylic acid isolated from the crude extract of Citrus microcarpa. Presently, there was no report on compound from C. microcarpa that possessed antimicrobial property against fish pathogenic bacteria. Therefore, in this study, the bioactive principle in C. microcarpa extract was isolated using thin layer chromatography. It＇s structure was elucidated based on nuclear magnetic resonance （NMR） spectroscopic data, such as proton NMR （1HNMR）, correlation spectroscopy, carbon 13 NMR, and heteronuclear multiple bond correlation data. This study showed that the bioactive compound isolated from C. microcarpa was 2-hydroxypropane-1,2,3-tricarboxylic acid monohydrate. The minimum inhibitory concentration （MIC） values of crude C. microcarpa extract and its bioactive component, 2-hydroxypropane-1,2,3-tricarboxylic acid as well as commercially available synthetic 2-hydroxypropane-1,2,3-tricarboxylic acid, were determined against 18 isolates of Edwardsiella tarda and 7 bacterial reference strains, namely, Escherichia coli （ATCC 25922）, Citrobacter freundii （ATCC 8090）, Aeromonas hydrophila （ATCC 49140）, Pseudomonas aeruginosa （ATCC 35032）, Streptococcus agalatiae （ATCC 13813）, E. tarda （ATCC 15947）, and Yersinia enterocolitica （ATCC 23715）, using two-fold microdilution method. The MIC values for both the natural 2-hydroxypropane-1,2,3-tricarboxylic acid and the synthetic one were ranging from 15.6 to 62.5 mg mL-1, whereas that of the crude extract was ranging from 7.8 to 31.3 mg mL-1. These findings showed that both the crude extract and its bioactive component might have potential as antimicrobial agent for aquaculture use.     

Serological survey for <Emphasis Type="Italic">Brucella</Emphasis> antibodies in donkeys of north-eastern Nigeria

A cross-sectional epidemiological study was conducted to determine seroprevalence and risk factors influencing the presence of Brucella antibodies in donkeys of Borno State, north-eastern Nigeria. The study aimed at providing baseline information that may be used in planning a control policy against equine brucellosis. Blood samples were collected from 601 donkeys, comprised of 374 males and 227 females from the six agricultural zones of the state between March 2013 and September 2014. The sera obtained were tested for Brucella antibodies using Rose Bengal plate test (RBPT) and competitive enzyme-linked immunosorbent assay (cELISA). Of the 601 donkeys tested, 43 (7.2%) and 40 (6.7%) were seropositive by RBPT and cELISA, respectively. A seroprevalence of 8.6% was obtained in male and 3.5% in female donkeys. According to age, the highest seroprevalence of 9.6% was obtained from donkeys of age group 4–6 years. With respect to pregnancy status, a higher seroprevalence (6.8%) was obtained from pregnant donkeys compared to 3.8% obtained from the non-pregnant ones. There were statistically significant associations between the presence of antibodies and sex (p < 0.05) and the presence of antibodies and age (p < 0.05) of the studied donkeys. However, no statistically significant association (p > 0.05) was observed between the pregnancy status and presence of antibodies. The study concludes that Brucella infection is present in donkeys in all the agricultural zones of the state. The relatively high seroprevalence (7.2%) obtained is of public health concern because of the close interaction between donkeys, ruminants, and humans in the study area.     

Mineral Nutrient Acquisition by Cotton Cultivars Grown under Salt Stress

Physiological responses were investigated in two cotton cultivars grown at various concentrations of sodium chloride (NaCl) in order to determine the degree of the tolerance of the cultivars to salt stress and understand the physiological responses with respect to utilization of mineral nutrients. After germination of the seeds of cotton cultivars, they were transferred into standard pots with 210 g sterilized compost and watered with 30 ml Hoagland’s solution containing different concentrations (0, 50, 100, 200, and 400 mM) of NaCl at two-day intervals for 3 months. Growth parameters were measured and the mineral nutrient analyses were done using inductively coupled plasma optical emission spectrometry (ICP-OES, Thermo Fisher Scientific, Waltman, MA). It was observed that plant growth and mineral nutritional status of both cultivars were altered extensively in those grown with NaCl. Excess NaCl reduces the concentrations of certain mineral nutrients and increases that of others, the patterns depending on the mineral nutrient and the plant part and varieties being compared to the control.     

Effect of Different Nitrogen Doses on Dry Matter Ratio,Chlorophyll and Macro/Micro Nutrient Content in Sweet Herb (Stevia rebaudiana Bertoni)

With this study, the effect of different nitrogen (N) doses applied to sweet herb (0, 50, 100, 150 and 200 N kg ha^?1) on the macro/micro nutrient element content, dry matter ratio and on the chlorophyll amount in the plant leaves is examined. The research was carried out in the research and trial field of Faculty of Agriculture Agronomy department, Akdeniz University, during the 2012–2013 growing season under field conditions for 2 years with four replications according to the randomized block trial design. Chlorophyll amounts were determined and the average was obtained with three readings from each leaf by a chlorophyll meter when the plants were in the beginning of flowering. Post-harvest macro and micro nutrient elements of the sweet herb were also investigated. According to the obtained data, while the highest chlorophyll and N amounts in the leaf for both the first and second years were determined as 46.97 SPAD (Minolta Corp, NJ, USA) and 1.34 N% 44.9 SPAD, 1.42 N%, respectively, under 200 kg ha^?1 N application, the lowest chlorophyll and N amounts were determined in the control group. In addition, N application in different doses for both years increased the phosphorus (P) and potassium (K) contents and increased the microelement contents, especially in the second year. At the same time, a correlation between the chlorophyll content in the plant leaves and the N amount was determined and a linear increase was observed in the chlorophyll amount with the increased green part.     

Antibiogram and heavy metal resistance of pathogenic bacteria isolated from moribund cage cultured silver catfish (<Emphasis Type="Italic">Pangasius sutchi</Emphasis>) and red hybrid tilapia (<Emphasis Type="Italic">Tilapia</Emphasis> sp.)

Antibiogram and heavy metal resistance patterns of pathogenic bacteria isolated from moribund cage cultured silver catfish (Pangasius sutchi) and red hybrid tilapia (Tilapia sp.) from Sungai Manir, Terengganu, Malaysia were studied and characterized. Sungai Manir is one of the famous rivers in Terengganu for its wide variety of cage cultured freshwater fish. However, to date, the baseline information of antibiogram and heavy metal resistance patterns of the pathogenic bacteria attacking the freshwater fish cultured in Sungai Manir is still lacking. Therefore, this study was carried out, which may be useful for fish farmers as a guideline for fish prophylactic and treatment purposes. Furthermore, present studies also provide information on the safety level of consuming freshwater fish produced from Sungai Manir. In the present study, bacteria were isolated from 100 fish of each moribund silver catfish and red hybrid tilapia using seven media including tryptic soy agar (TSA), Mac Conkey, thiosulphate citrate bile salt (TCBS), eosin methylene blue (EMB), glutamate starch pseudomonas (GSP), xylose lysine deoxycholate (XLD) and Baird Parker media. Identification of bacteria was carried out using conventional biochemical tests and confirmed by commercial bacterial identification kit. Antibiogram of the bacterial isolates against 18 antibiotics; oxolinic acid (2 μg), ampicillin (10 μg), erythromycin (15 μg), furazolidone (15 μg), lincomycin (15 μg), oleandomycin (15 μg), amoxicillin (25 μg), colistin sulphate (25 μg), sulphamethoxazole (25 μg), chloramphenicol (30 μg), doxycycline (30 μg), florfenicol (30 μg), flumequine (30 μg), kanamycin (30 μg), nalidixic acid (30 μg), tetracycline (30 μg), nitrofurantoin (50 μg) and spiramycin (100 μg) was carried out using disk diffusion method, whereas heavy metal resistance patterns (Hg²⁺, Cd²⁺, Cr^{6 +} and Cu²⁺) of the bacterial isolates was determined through twofold agar dilution method. The results showed that the percentage of sensitivity case of the 120 bacterial isolates to the tested antibiotics was 62.7%. This was followed by resistance (26.9%) and intermediary sensitive (10.4%) cases. In terms of the heavy metal resistance patterns, all bacterial isolates were resistant to Hg²⁺ and Cr^{6 +}. However, only 27.8% and 16.7% of the bacterial isolates were sensitive to Cu²⁺ and Cd²⁺, respectively. The multiple antibiotic resistance (MAR) indices indicated that the cage cultured silver catfish and red hybrid tilapia were under high exposure to the tested antibiotic. Overall, the results of the present studies showed that Sungai Manir may be polluted with heavy metal and antibiotic residues.     

Some clinical, haematological and biochemical effects of four tranquilizers in camels (Camelus dromedarius)

Six healthy camels were treated with the tranquilizers propionyl promazine (Combelen), xylazine (Rompun), acepromazine (Calmivet) or chlorpromazine (Largactil) at single intramuscular doses of 0.5, 0.25, 0.1, or 3 mg/kg, respectively; and the onset, duration and degree of sedation produced by each drug was assessed for six hours. The effect of the treatments on some haematological and biochemical parameters was also studied. The onset and duration of action of the tranquilizers were 10 min and 2.1 +/- 0.5 h for propionyl promazine, 4 min and 3.1 +/- 0.4 h for xylazine, 5 min and 2.3 +/- 0.5 h for acepromazine, 7 min and 2.5 +/- 0.4 h for chlorpromazine, respectively. It was observed that 5-10 min after the administration of the four drugs, camels showed slight irritability, dropping of the lower lips and scratching of the nostrils against objects. During the first hour after medication camels showed frequent urination, defaecation and lacrimation. Xylazine seemed to be superior to the other three drugs in producing sedation. No significant effect on the rectal temperature or the respiratory rates of treated camels was seen after the administration of the four drugs. There were consistent, but statistically insignificant decreases (about 10 p. 100) in the haemoglobin concentration and erythrocyte counts of camels one hour after treatment with the tranquilizers. The four drugs, particularly xylazine and propionyl promazine produced significant hyperglycaemia, but did not alter significantly the plasma concentration of urea or activity of aspartate aminotransferase.     

Efficiency of drained selection environments for improving grain yield in faba bean under undrained target environments on vertisol

Waterlogging is a major constraint of faba bean (Vicia faba L.) production in the highland vertisols of Ethiopia. Genotypes are currently evaluated under both the drained conditions of Broad Bed and Furrow(BBF) and the undrained flatbeds. The objective of this research was to determine if selection of genotypes under BBF is efficient for identification of genotypes for the flatbed conditions. Yields under the flatbed conditions were lower by 20–50% (38% on average) than yields under the BBF. Genetic variation, heritability and predicted genetic gains for grain yield due to direct selection were also lower under the flatbeds than they are under the BBF. There were good levels of genetic correlation (r = 0.20–0.75 or0.45 on average) between yield performances under BBF and flatbeds, indicating that selection under BBF may identify good genotypes for flatbeds and vice versa. There was also high association (r =0.91) between relative yield reduction under flatbeds and the ratio of the predicted genetic gains from indirect selection under BBF to the predicted genetic gains from direct selection under flat beds. This indicates that indirect selection under BBF may be useful to identify better genotypes for flatbed conditions, but the relative efficiency of indirect selection was lower than direct selection under flatbeds themselves. This revised version was published online in August 2006 with corrections to the Cover Date.     

Genetic nature of bacterial wilt resistance in tomato (lycopersicon esculentum Mill.) accession La 1421

The genetic nature of bacterial wilt resistance in tomato was studied in two crosses based on the number of days of survival (quantitative) in the field before the appearance of wilt symptoms. Significant differences were observed between generation means in both crosses (LA 1421 × Cascade and LA 1421 × Caraibo). This study indicates that resistance identified in Lycopersicon esculentum var. cerasiforme LA 1421 may be different from that derived from L. pimpinellifolium. However, the genetic mechanism seems to be complex with a duplicate form of epistasis. Results suggest that selection for resistance from crosses between LA 1421 and Cascade should preferably be delayed until a high level of fixation of genes is attained. The variation observed in the F₂ and BC₂ progeny of the Caraibo cross, suggested that genetic combination between the two resistance sources can lead to higher levels of resistance. This revised version was published online in July 2006 with corrections to the Cover Date.