Polycyclic aromatic hydrocarbons biodegradation using isolated strains under indigenous condition

The treatment and disposal of domestic sIudge is an expensive and environmentally sensitive problem. It is also a growing problem since sludge production will continue to increase as new wastewzter treatment plants are built due to population increase. The large volume of domestic sIudge produced had made it difficult for many countries including Malaysia to assure complete treatment of the sludge before discharging to the receiving environment. Domestic sludge contains diverse range of pollutants such as pathogen, inorganic and organic compounds. These pollutants are toxic, mutagenic or carcinogenic and may threaten human health. Iiilproper disposal and handling of sludge may pose serious impact to the environment especially on soil and water cycles. Previous studies on Malaysian domestic sludge only reported on bulk parameters and heavy metals. Thus, no study reported on organic micro pollutants, namely, polycylic aromatic hydrocarbons (PAHs). Their recalcitrance and persistence make them problematic environmental contaminants. Microbial degradation is considered to be the primary mechanism of PAHs removal from the environment. Much has been reported on biodegradation of PAHs in several countries but there is a lack of information quantitative on this subject in Malaysia. This study is carried out to understand the nature of domestic sludge and to provide a better understanding on the biodegradation processes of PAHs. The methodology of this study comprised field activities, laboratory work and mathematical modelling. Field activities involved sampling of domestic sludge from Kolej Mawar, Universiti Teknologi MARA, Shah Alam, Selangor. Laboratory activities include seven phases of experimental works. First phase is characterization study of domestic sludge based on bulk parameters, heavy metals and PAHs. Second phase is enrichment and purification of bacteria isolated from domestic sludge using single PAHs and mixed PAHs as growth substrate. This was followed by identification of bacteria using BIOLOG system. The fourth phase focussed on turbidity test to monitor growth rate of the isolated bacteria. Preliminary degradation study involves optimization of the process at different substrate concentration, bacteria concentration, pH and temperature. The optimum conditions established from optimization study were used in degradation study. In biodegradation study, two experimental conditions were performed. These conditions include using bacteria isolated from single PAHs as substrate and bacteria isolated from mixed PAHs. Protein and pH tests were done during degradation study. Final activity is mathematical modelling of the biodegradation process. In general results on bulk parameters are comparable to previous studies. Zinc was the main compound with a mean concentration of 11 96.4 mglkg. PAHs were also detected in all of the samples, with total concentration between 0.72 to 5.36 mglkg dry weight for six PAHs. In the examined samples, phenanthrene was the main compound with a mean concentration of 1.0567 mglkg. The results fiom purification studies of bacteria strains sucessfull isolated 13 bacteria strains fiom single PAH substrate while three bacteria were isolated from the mixed PAHs substrate. Based on bacteria growth rates, only six strains grown on single PAHs and three strains grown on mixed PAHs were used for further studies. Results from the optimization study of biodegradation indicated that maximum rate of PAHs removal occurred at 100 mg~-' of PAHs, 10% bacteria concentration, pH 7.0 and 30°C. The results showed that bacteria grown on lower ring of PAHs are not able to grow on higher ring of PAHs. As for example Micrococcus diversus grown on napthalene as sole carbon source was unable to degrade other PAHs like acenapthylene, acenapthene, fluorene, phenanthrene and antlracene. In the case of bacteria isolated from mixed PAHs, the results showed that most of the napthalene was degraded by isolated strains with the highest average degradation rate followed by acenapthylene, acenapthene, fluorene, phenanthrene and anthracene. 377$3(53867$.$$1�781.8�781�$0,1$+ D4ff + c\,cpda~ition trends were observed in the study could be attributed to the different subsr , i,lo\~ir 'Led during isolation process. Interaction through cometabolism and synergistic ocolq bacteria strains isolated from single substrate. Thus, only synergistic interaction was oL, :a 77ed for bacteria isolated from mixed substrate. Corynebacterium urolyticum re\e;;ed I,, be the best strain in degrading PAHs. The experimental results have led to a model conccl~t desclibing I'AHs degradation

Vermicomposting of food waste

The use of food waste recycling concept can be an interesting option to reduce the use of landfill. This strategy is more environmental friendly, cheap and fast if proper management to treat the food waste is applied. Nowadays, the concept of recycling is not well practice among the community. In this study, vermicomposting is introduced as an alternative of the food waste recycling. Vermicomposting consists of the use of earthworms to break down the food waste. In this vermicomposting treatment, the nightcrawler earthworm are used to treat the food waste. The food will be collected from UTHM cafe. The experiment consist of peat soil as a base, earthworms and the food waste. The pH number and moisture content of each container were controlled at 7.0 to 7.2 and 60 to 80 % to maintain the favorable environment condition for the earthworms. The weight of the sample will be measured in three days time after exposure to the earthworm. The vermicomposting study was taken about two weeks time. After the treatment, the soil sample are tested for nitrogen (N), Phosphorus (P), and Potassium (K) concentration. Based on the result obtained, it shows that vermicomposting will reduce the weight of treatment sample and the concentration of N, P, and K for the soil is greater than the chemical fertilizer. Therefore, vermicomposting is a promising  alternative treatment of food waste as it is more ecofriendly

The relationship between employment with labour productivity, capital productivity and output of small and medium sized enterprise (SME) in manufacturing industry / Norzila Othman

The purpose of this study is to determine the relationship between employment with labour productivity, capital productivity and output of Small and Medium Sized Enterprise (SME) in Manufacturing Industry. This study includes data from year 2002-2006. For this purpose all the data will be analyze using the correlation analysis to see the relationship between each variable. The data that being used in this study is the growth performance of employment, labour productivity, capital productivity and output of Small and Medium Sized Enterprise (SME) and concentrated on the manufacturing industry. For data analyzing, this study used SPSS to get the result. Based on the analysis only capital productivity that have a significant relationship with employment

A review on the influence of drinking water quality towards human health

An adequate supply of safe drinking water is one of the major prerequisites for a healthy life. Inadequate of safe drinking water produce waterborne disease and a major cause of death in many parts of the world, particularly in children. Therefore, it must be treated properly before it can be used and consumed. This chapter provides the guidelines of important parameters for drinking water standard in order to ensure the safeness of drinking water. All the selected parameters were elaborated on the effect of high concentration if human consume the drinking water directly

Waste to wealth: production of activated carbon from agricultural waste

Adsorption is the main process for wastewater and drinking water treatment. The ability of activated carbon as an absorbent was proven by many researchers. Agriculture waste can be produced as an activated carbon based on availability, cost, and purity. Physical and chemical activations are the main process in activated carbon (AC) development. Both processes have its own advantage. Before proceeding with the activation process the precursor must be characterized for metal element and surface functional group by doing (X-Ray Fluorescence) XRF and Fourier transform infrared (FTIR). TGA will determine the exact carbonization temperature. Adsorbent pore will be analyzed using BET. Activating agent and carbonization temperature gives the main effect for surface area and total pore volume of AC. This chapter will review the AC development process and the exact characterization method in preparing the AC

Keberkesanan cerpen dalam mempertingkatkan prestasi penulisan karangan Bahasa Melayu dalam kalangan murid

This research analyses the effectiveness of literature texts to upgrade the performance of 64 average-achiever students in Form Two. This experimental research was conducted to compare the effectiveness of the use of literature texts and conventional methods of teaching composition. Both groups were given two tests, namely pre-test and post-test to compare the performance of the overall composition, elaboration of points and sentence type. The research findings of the pre-test and post-test show that the teaching of composition using the literature texts is more effective than the conventional method

Potential of Using ROSA Centifolia to Remove Iron and Manganese in Groundwater Treatment

Groundwater is source for water supply because of its good natural quality. However, groundwater may be exposed toward to contamination by various anthropogenic activities such as agricultural, domestic and industrial. Groundwater quality problem are typically associated with high hardness, high salinity and elevated concentration of iron, manganese, ammonium, fluoride and occasionally nitrate and arsenic.  Therefore, groundwater should be treated to acceptable level before consumption. This study is carried out with the objectives to optimize the feasibility condition of contact time, biosorbent dosage and pH range in removing heavy metal by using Rosa Centifolia (R. Centifolia) and also to determine the water quality of groundwater sources.  A dried Rosa Centifolia pretreated before being used as biosorbent. Experiment was done by varying contact time, biosorbent dosage and pH range to get the optimum value. The removal characteristic of Iron and Manganese by Rosa Centifolia was analyzed using Atomic Absorption Spectrophotometer (AAS). The optimum condition is achieved at 240minutes, 0.05g/ml and pH 5 respectively. The optimum percentage removal of Iron and Manganese was found to be more than 70%. The finding indicated that Rosa Centifolia is a promising biosorbent in treating groundwater from RECESS UTHM well

Efficiencies and mechanisms of steel slag with ferric oxides for removing phosphate from wastewater using a column filter system

The current study aimed to investigate the efficiencies and mechanisms of slag filter media for removing phosphorus from synthetic wastewater. The steel slag with high ferric oxides (Fe2O3) was subjected for the electric arc furnace (EAF) and selected as the filter media (HFe). The chemical characteristics of HFe were determined using pH, point of zero charge (PZC) and XRF. The phosphorus removal efficiency was studied in a designed vertical steel slag column rock filters in unaerated HFe (UEF) and aerated HFe (AEF) system. The microstructure of HFe was analyzed by FTIR, XRD and SEM-EDX analysis. The results of XRF revealed that ferric oxide (Fe2O3) ranged from26.1 to 38.2%. PZC for Filter HFe was recorded at pH 10.55 ± 0.27. The highest efficiencies were recorded by UEF and AEF systems at pH 3 and pH 5 (89.97 ± 4.02% and 79.95 ± 6.25% at pH 3 and 72.97 ± 8.38% and 66.00 ± 12.85% at pH 5 for UEF and AEF, respectively). These findings indicated that AEF exhibiting higher removal than UEF systems might be due to presence high Fe concentration in AEF which play important role in the phosphorus removal. The main elements available on the surface of HFe included carbon, oxygen, iron, calcium, magnesium, silicon, platinum, sulphur, manganese, titanium and aluminium. The XRD analysis indicated that the precipitation of orthophosphate as calcium and iron-phosphates was the removal mechanism as confirmed using FT-IR analysis. These findings demonstrated the efficiency of HFe in removing of phosphorus from wastewater

Bioremediation a potential approach for soil contaminated with polycyclic aromatic hydrocarbons: An Overview

Polycyclic aromatic hydrocarbons (PAHs) represent a group of priority pollutants which are present at high concentration in soils of many industrially contaminated sites. Standards and criteria for the remediation of soils contaminated with PAHs vary widely between countries. Bioremediation has gained preference as a technology for remediation contaminated sites as it is less expensive and more environmental friendly. Bioremediation utilizes microorganisms to degrade PAHs to less toxic compounds. This technology degrades contaminants through natural biodegradation mechanisms or enhanced biodegradation mechanism and can be performed in-situ or ex-situ under aerobic or anaerobic conditions. The purpose of this paper is to highlight potential of using isolated strains from municipal sludge on soil remediation. Several indigenous bacteria from municipal sludge namely genus Micrococus, Sphingomonas, and Corynebacterium demonstrated a high removal rate of PAHs with more than 80% of lower molecular weight of PAHs degraded after one week incubation. Laboratory studies had established that these genus able to degrade PAHs on contaminated soil. The successful application of bacteria to the bioremediation of PAHs contaminated sites requires a deeper understanding of how microbial PAH degradation proceeds. An overview of research focusing on biodegradation of PAHs will be presented

A Chemical and Morphological Study of Cassava Peel: A Potential Waste as Coagulant Aid

This study investigates the chemical and morphological characteristics of cassava peel (CP) biomass as a potential coagulant aid for turbidity, heavy metals and microbial removal. FE-SEM micrograph shown the surface of the CP samples was covered with smooth and globular in shaped of bound starch granules. FTIR spectra demonstrated that carboxyl and hydroxyl groups were present in abundance. Whereas analysis by XRF spectrometry indicated the CP samples contain Fe2O3 and Al2O3 which might contribute to its coagulation ability. The features of CP obtained from this study promotes the feasibility of CP to be further developed and studied to produce effective coagulant aid as sustainable alternative to reduce the usage of chemical coagulants