Annual Research & Review in Biology

Heavy metals, as essential or non-essential ones, are present in aquatic systems at different levels. The over limited concentration of metals has a negative effects as physiological, histological and morphological patterns. The levels of contaminants in fish are of particular interest because of potential risk to human consuming them. Heavy metals bring about their effects as single or mixture on organs or tissues of fish. The influence starts at cellular or molecular level, then being at population level, particularly through early stages of development, and may result in species extinction, due to tendency towards accumulation and reduced biodegradation. The liver, gills and kidney seem to be the most interested organs included in current studies due to their sensitized feature towards metal impact. Fishes could be employed as biomarker indicator for environmental contamination, in particular with long term monitoring, and with trace levels of pollutants. Overlap between different factors, along with integrated responses must be considered in determination of heavy metals impact, in complementary of water quality parameters; and so, standardized methods being necessary for comparison among variable results obtained. This study is an interpretative effort of some aspects included in toxicity of five heavy metals for fish species.

Owing to the growing of diseases caused by infectious pathogens as well as toxicants, it is needed to develop targeted nanotechnology-based system in order to treat specific diseases. The treatments with conventional antimicrobial and anticarcinogenic agents against diseases have associated the development of multi drug resistance, high toxic side effects, inadequate therapeutic index and low bioavailability of drugs. In this concern, site- specific drug delivery may be an important arena of research to enhance drug-efficacy and reduce adverse side effects to host cells while antimicrobial and anticarcinogenic nanosized gold materials have emerged as potent drug delivery vehicles against various diseases due to their unique size dependent physico-chemical and optical properties, ease of surface modification and high surface-to-volume ratio associated active functional groups, and bio- compatibility. This review focussed on mainly gold nanoparticles (AuNPs), along with their mechanism of actions, biodistribution, pharmacokinetics, toxicities, host-immune response, and their potential applications against a lot of diseases. The review also demonstrated on the development of AuNPs coated drugs, ligands such as chitosan, polyethylene glycol (PEG) / polyethylene imine (PEI) with / without sugars, peptides, proteins, antibodies and genes as drug delivery carriers for targeting small molecules and drugs to diseased sites.

Aims: The aim of this study was to investigate different levels of CO₂ availability alters total phenolic and flavonoid, total available carbohydrate (TAC) and to determine how elevated CO₂ influences gas exchange of Labisia pumila seedlings.

Study Design: The 3-months Labisia pumila seedlings of var Alata, var Pumila and var Lanceolata were put under 1 month to acclimatize in a nursery until ready for the treatment. Carbon dioxide enrichment treatments started when seedlings reached 4 months old by exposing them to three levels of CO₂, viz., ambient CO₂ (400 µmol/mol), twice ambient (800 µmol/mol) and thrice ambient CO₂ (1200 µmol/mol). The split plot 3 x 3 factorial experiment was designed using randomized complete block design with CO₂ levels being the main plot and varieties as the sub-plot replicated three times.

Place and Duration of Study: Ladang 2, Universiti Putra Malaysia Glasshouse complex between July to November 2011.

Methodology: The experiment was conducted for 15 weeks. The measurement of photosynthesis was obtained from a closed infra-red gas analyzer LICOR 6400XT Portable Photosynthesis System (IRGA, Licor Inc., USA). Total phenolics and flavonoid were determined using Follin–Ciocalteau reagent and  total available carbohydrate using anthrone reagent.

Results: It was found that the treatment effects were contributed by CO₂ levels in all weeks measured in leaf gas exchange properties (Net photosynthesis (A), stomatal conductance (g_s), transpiration rate (E), intercellular CO₂ (C_i) and Instantaneous water use efficiency, WUE). A combination of increases rates of A and E was responsible for enhancement of WUE by 50% in elevated treatment (800 and 1200 µmol/mol). Total available carbohydrate, total phenolics and flavonoid were also influenced by elevated CO₂ in all weeks of measurement. At end of 15 weeks after treatment (WAT), 44% increase in total available carbohydrate had increased total phenolic and flavonoid by 56% and 149% respectively than ambient treatment. At end of 15 WAT It was found, that the photosynthetic capacity of Labisia pumila was enhanced under elevated CO₂ by significantly have higher maximum electron transfer rate, J_max and Rubisco CO₂fixation capacity V_cmax than ambient seedlings.

Conclusion: In this work, it was observed that the increase in production of total phenolics and flavonoid in L. pumila might be due to increase in production of total available carbohydrate in the present study. The upregulation of photosynthesis in the present study was supported by enhancement of Maximum electron transfer rate, J_max and Rubisco CO₂ fixation capacity V_cmax than ambient seedlings that showed this plant has high sink strength to cope with high level of CO₂.

Background: Launaea taraxacifolia (Willd) Amin Ex.C Jeffrey is an undervalued traditional leafy vegetable, which is economically important as food and medicine. It also has several therapeutic and nutritive values. The cultivation is hampered by low seed viability, seed dormancy and poor vegetative propagation.

Aim: The study aimed to develop an efficient protocol for micropropagation of L. taraxacifolia.

Place and Duration of Study: The study was conducted at the tissue culture laboratory of National Centre for Genetic Resources and Biotechnology, Moor Plantation, Ibadan. Nigeria.

Methodology: One centimetre (1.00 cm) double-sterilized single-node explants of L. taraxacifolia cultured on Murashige & Skoog (MS) medium amended with a constant concentration (0.5 mg/l) of 1-Naphthaleneacetic acid (NAA) in combination with varying concentration (0.5 mg/l, 1.0 mg/l,   1.5 mg/l, 2.0 mg/l and 2.5 mg/l) of two cytokinins, 6-Benzylaminopurine (BAP) and kinetin were investigated for their effects on shoot proliferation, multiplication and rooting. Growth parameters were observed and recorded and the data subjected to statistical analysis.

Results: Among the cytokinin treatments, significant increase in means was observed with increase in the concentration of BAP. There was no significant difference among the treatments with kinetin.  BAP treatments at 2.5 mg/l gave significantly highest number of shoots (3.33 and 4.67) and number of leaves (16.70 and 30.00) at 4 and 8 weeks of culture, respectively as compared to the control. Shoot length was highest in treatment with MS+2 mg/l BAP+0.5 mg/l NAA and MS+1 mg/l KIN+0.5 mg/l NAA (2.33 and 0.30) and these were higher than that of control at 4 weeks and equal at 8 weeks. Residual effect of the Plant growth regulators (PGRs) was observed in treatment with MS+0.5 mg/l KIN+0.5 mg/l NAA alone.

Conclusion: The results from the study revealed that L. taraxacifolia nodal explants resulted in multiple shoots in BAP treatments than in kinetin treatments. Double disinfection with treatment with MS+2.5 mg/l BAP+0.5 mg/l NAA which produced the highest number of clean multiple shoots and leaves is thereby proposed as shoot multiplication medium for this species.

This paper presents the effects of probiotic additive “Vetosporin-Active” dietary supplementation on the livability and weight gain of chicken broilers. The “Vetosporin Active” probiotic additive based on two bacillus subtilis strains (Bacillussubtilis 11 В и Bacillussubtilis 12В). Four hundred broilers were allocated to four groups. The first group (I) was the control, fed with a diet without the addition of the probiotic. For II, III and IV groups the “Vetosporin Active” probiotic additive was incorporated in the diet at the level of 0.5, 1 and 1.5 g/kg, respectively. Dietary supplementation of broilers with 1 g/kg of “Vetosporin-Active” increased the average daily weight gain of chicken broilers (13.1%). The data analysis showed that the highest weight gain of chicken-broilers was observed during the first week of their life.