International Letters of Natural Sciences Vol. 13

Abstract: Recently, algae have become significant organisms for biological purification of wastewater since they are able to accumulate plant nutrients, heavy metals, pesticides, organic and inorganic toxic substances and radioactive matters in their cells/bodies. Biological wastewater treatment systems with micro algae have particularly gained importance in last 50 years and it is now widely accepted that algal wastewater treatment systems are as effective as conventional treatment systems. These specific features have made algal wastewaters treatment systems an significant low-cost alternatives to complex expensive treatment systems particularly for purification of municipal wastewaters. By this method 70 % of biological oxygen demand, 66 % of chemical oxygen demand, 71 % total nitrogen, 67 % of phosphorus, 54 % volatile solid and 51 % of dissolved solid was reduced

Abstract: Space weather has a close connection with the interaction of the Earth and the Sun. As equatorial country, the characteristic features of the climate of Malaysia are uniform temperature, very high humidity and copious rainfall. Malaysia has an average of temperature of 26.7 °C per year. Therefore, it is suitable to monitor the Sun. In the following work, we will emphasize the development of Sun monitoring in Malaysia. The number of observatories are increasing. A dedicated work to understand the Sun activity in radio region is a part of an initiative of the United Nations together with NASA in order to support developing countries participating in „Western Science‟ research. Realizing how important for us to monitor the space weather, therefore, we have been utilizing the new radio spectrometer, CALLISTO (Compound Low Cost Low Frequency Transportable Observatories) spectrometer. Malaysia is one of the earliest country from South- East Asia (ASEAN) that involve this research. One of the advantages to start the solar monitoring in Malaysia is because our strategic location as equator country that makes possible to observing a Sun for 12 hours daily throughout a year. We strongly believe that Malaysia as one of contributor of solar activity data through E-CALLISTO network. This is a very good start for developing a space weather in Malaysia. With the implementation of CALLISTO systems and development of solar monitoring network, a new wavelength regime is becoming available for solar radio astronomy. Overall, this article presents an overview of space weather in Malaysia. With the present level of the international collaboration, it is believed that the potential involvement of local and international scientist in space weather will increase.

Abstract: This survey work summarizes the generation of indoor air pollutants (IAPs) through household products and activities and also the probable health symptoms of IAPs were discussed through questionnaire in the residential buildings of urban and semi urban area when compared to rural (control) area by door to door survey. The IAPs are categorized as physical, chemical and biological and surveyed as per the product(s) usage in the closed room of buildings. The survey results of IAPs generated from household products and activities, these are asbestos, fine particulate matters and ash as physical pollutants. The chemical pollutants are carbon mono and di oxide gases, phthalates; DDT, chlordane, heptachlor, o-phenylphenol; PBDEs, Formaldehyde, Other Aldehydes, lead, benzene, chloroform, para-dichlorobenzene, methylene chloride, perchloroethylene, styrene, benzene, formaldehyde, terpenes, styrene, phthalate esters, toluene, Propellant, pesticides, PAH, NOx, acrylamide, VOCs, acetone, HCl gas and biological pollutants are bacteria, fungi, viruses, house dust mites, animal dander; cockroaches, microbial spore. In respect to established health impact data, the health symptoms were recorded after survey in two areas viz. urban and semi urban area. The health symptoms were recorded as eye, nose, and throat irritation; allergic reactions, respiratory irritation, aggravated asthma, influenza and other infectious diseases may be the generation of IAPs. The urban and semi urban area are compared with rural (control) area in which no symptoms were found as per discussion. In the present survey it was concluded that the generation of IAPs may from household products and activities in the urban and semi urban area due to less ventilation facilities when compared to rural (control) area. This is a preliminary observation, further researches are needed in relation to measurement of physical, chemical and biological indoor pollutants in closed room of residential buildings and also health hazards study of residents by haematological, biochemical, enzymological and genotoxicological parameters.

Abstract: The research methodology recommended by the OECD (Organization of Economic Co-operation and Development) and ISO (International Organization for Standardization) guidelines for testing of chemicals meets the most criteria expected for ecotoxicological testing except the testing condition and the organic matter. The guidelines were initially developed by temperate countries, with testing conditions as 20 °C and the organic matter as sphagnum peat which is commonly available in those countries. But these two criterions are difficult to be followed in tropical countries. Thus there arises a need of modifying these criterions for toxicity studied in tropical regions. In this study a trial was made for substituting the fermented coir pith for sphagnum peat and the validation of the modified tropical artificial soil (TAS) was done by conducting chronic toxicity studies on Eisenia fetida against an inorganic fertilizer, superphosphate (SP) under tropical condition, i.e., 28 ±2 °C. The performed study showed that the SP determined lower earthworm mortality in TAS comparing to OECD soil for all tested concentration levels. The number of juveniles produced in OECD soil was also significantly reduced (p < 0.05) than in TAS. This may be due to the production of large amount of hydrogen ions when the temperature increases and making the medium acidic. The fermented coir pith was more suitable for ecotoxicity studies under tropical condition than sphagnum peat.

Abstract: Fruits of Eugenia jambolana were analysed for total phenolics and antioxidant activity of three successive development stages viz. 1. Mature green 2. Half - ripened and 3. Fully ripened. The total anthocyanin concentrations were higher in fully ripened stage, the total phenolic content was maximum achieved in mature green stage (354 mg L^-1). Antioxidant activity also strongly depended on ripening stages, showing completely opposite compared to that of total phenolics. Since total phenolics and antioxidant activity performed nearly “Object and its reflection in the mirror” trend.

Abstract: During the past two decades, Arsenic (As) contamination via groundwater has become a serious issue worldwide and is now a major concern in the Indo-Bangladesh Gangetic delta. Arsenic enters human body through contaminated groundwater consumed as drinking water. Food safety in this region is also facing severe consequences as bio-accumulation of Arsenic is occurring in food crops irrigated with As-contaminated water. Chronic exposure to Arsenic can cause not only cancerous and non-cancer health effects. Reports suggest that about 20 % population in West Bengal is highly affected. Various techniques are being introduced to provide arsenic-free drinking water at an affordable cost. But a rigorous change in habit and mind set for procuring safe drinking water in those surviving in As-contaminated zones is the most essential step towards curbing the fatal consequences of As exposure. Harvesting rain water and utilization of proper purification techniques can be considered a possible alternative of safe drinking water.

Abstract: Biofertilizers have been used as sources to improve plant nutrients in sustainable agriculture. Biofertilizers are low cost, renewable sources of plant nutrients which supplement chemical fertilizers. Mycorrhizal fungi are a major component of agricultural natural resources and members of kingdom fungi. The term ‘mycorrhiza’ is derived from Greek word which means ‘fungus root’. Earthen pot experiments were carried out to study the inoculation effect of Arbuscular Mycorrhizal (AM) fungi (Glomus mossease), Azospirillium brasilense and PSB on plant height, dry weight of root and shoot, per cent root colonization, spore number, P and N uptake. Experimental pots were filled with 4 kegs of sterilized soil and maintained in green house at 25-30 °C temperature. Single inoculation of AM fungi and combined inoculation of AM fungi with Azospirillium brasilense or PSB was found to be moderately increased in all the growth parameters. However triple inoculation of AM fungi, Azospirillium brasilense and PSB was found to have highest growth parameters.

Abstract: The aqueous extracts of leaf of Citrus aurantifolia L were assessed in vitro for inhibitory activity against Macrophomina phaseolina isolated from dry root rot specimens of Gingelly. The antifungal activity was determined by poison food technique. The extracts have shown dose dependent inhibition of mycelial growth of test fungi. The extracts were more effective in inhibiting Macrophomina phaseolina. The extracts of Citrus aurantifolia were found effective against Gingelly dry root rot pathogens. Further field experiments are to be carried out to recommend the extracts against the disease.

Abstract: A study was conducted to determine the Production of cellulase and pectinase enzyme by using Plant growth promoting rhizobacteria like Pseudomonas fluorescence and Bacillus subtilis. These to micro organism are isolated by serial dilution method. One gram of soil sample was diluted in to 10 ml of sterile distilled water and 1 ml of sample solution was serially diluted in 9ml of sterile water up to 10 dilution. Each sample from dilution 10^-5 and 10^-6 were taken and streaked in to KB and NA medium and incubate at 24 hrs. After 24 hrs Pseudomonas fluorescence and Bacillus subtilis was observed in the medium of KB and NA medium. Both the culture was sub cultured and maintain in the same for the further work. CMCase medium was prepared and sterilized by autoclave for 121 °C for 15 minutes after sterilization these medium contain petriplate was streaked by bacteria and incubates for 48h after incubation period a clear halo zone was produced by these bacteria among these bacteria Pseudomonas fluorescence are able to produce high amount of cellulose compare to Bacillus subtilis. Pectin agar medium was prepared and sterilized by autoclave for 121 °C for 15 minutes after sterilization these medium contain petriplate was streaked by bacteria incubates for 48h after incubation period a clear halo zone was produced by these bacteria, among these bacteria Pseudomonas fluorescence are able to produce high amount of Pectinase compare to Bacillus subtilis. Plant growth promoting rhizobacteria (PGPR) are beneficial bacteria that colonize plant roots and enhance plant growth by a wide variety of mechanisms.

Abstract: The present research was carried out to evaluate response of Bell peppers (Capsicum annuum L.) to plant density and nitrogen fertilizer under field conditions. Plant density at four levels (20×50 cm, 30×50 cm, 20×100 cm and 30×100 cm) and nitrogen treatments at four levels (0, 50, 100 and 150 kg·N·ha^-1) were applied. Plant height, lateral stem number, leaf chlorophyll content, yield, and were assessed at immature and mature stages. The results showed that vegetative growth characteristics (plant height, lateral stem number and leaf dry matter) and reproductive factors (fruit volume and fruit weight) decreased with increasing plant density, but total yield (kg·ha^-1) increased with increasing plant density. The highest and lowest total yields were obtained by plant density 20×50 cm and 30×100 cm respectively. Nitrogen fertilizer was significantly affected on plant height, lateral stem number and leaf chlorophyll content. It was observed that fertilization with 150 kg·N·ha^-1 resulted to the highest fruit volume and plant yield. There were significant differences between fruit volume and fruit weight by interaction between plant density and nitrogen treatments.