Abstract. Greywater (GW) is identified as waste disposal from home activites that is discharging from laundry, bath and wash-basin. GW useful in irrigation of a garden and aids to reduce cost as well as maintain the environmental prosperity. This paper discussed the effectiveness of Botryococcus sp. to clean GW in phycoremediation treatment. This process involves as growing the Botryococcus sp. in the GW which is contributing to utilize supplements in GW for its grow. The results indicated that Botryococcus sp. is effective to reduce COD (88%), BOD (82%), TIC (76%), TC (58%), TN (52%), TOC (39%), Phosphate (37.5%) and pH (7%) for 100% concentration of GW. Meanwhile, for the 50% of GW concentration Botryococcus sp. capable to remove such as COD (83%), TIC (82%), BOD (68%), TN (67%), Phosphate (36.8%), TC (34%), TOC (31%) and pH (1.2%). Then, the study concludes that Botryococcus sp. can grow effectively in GW and be able to reduce the rate of nutrient in GW.

Abstract. Dairy wastewater are usually much polluted due to the high level of nutrient content such as phosphate, nitrate, sulfate etc. The pollution level are indicated by few characteristics such as BOD (243 mg/L), COD (324 mg/L), pH (9.08), Total Nitrogen (65.06 mg/L), Total Organic Carbon (143.3 mg/L), Total Carbon (312.9 mg/L) and Inorganic Carbon (169.6 mg/L). In this study, Botryococcus sp., a species of green microalgae are used to determine whether it can purify dairy wastewater. In spite of that, the microalgae growth over phycoremediation process also determined daily based on hemocytometer counting. From 100% concentration of dairy wastewater, Botryococcus sp. was capable to reduce the parameters such as BOD of 73.3%, TOC of 65.1%, TC of 61.4%, IC of 58.3% and COD of 48.8% on the 15 days of phycoremediation. Meanwhile, for the 50% of dairy wastewater, the same microalgae be able to remove the parameter such as phosphate of 78.7%, BOD of 73.8%, TOC of 70%, TC of 68,8%, IC of 59.4% and COD of 50%. The overall result from this study shown that the Botryococcus sp. is useful to reduce the inorganic and organic pollutant in dairy wastewater and could be potential to be used for any different wastewater.

The proliferation of indoor airborne microorganism in public institutional buildings such as schools and universities is often regarded as a potential health hazards to the buildings’ users. This issue is not new in Malaysia, a country with humid climate which favours the growth of microorganism. However, there is lack of research’s data, especially in higher institutional buildings in this country. The assessment of the indoor air quality is conducted in a university’s two new commissioning buildings located at Southern Peninsular of Malaysia. Both buildings utilized centralized air conditioning system. Concentrations of airborne microorganism were determined using a single-stage impacter (biosampler) as per requirement of National Institute of Occupational Safety and Health (NIOSH) Manual Analytical Method 0800. The acquired readings were compared to the standard level determined in Industry Code of Practice on Indoor Air Quality (ICOP IAQ) 2010. Other parameters such as relative humidity, temperature, and air velocity were recorded along the assessment. The mean concentrations of the total bacteria at the affected area of the two buildings are 1102.5 CFU/m3 and 813 CFU/m3 respectively and it is significantly higher compared to the maximum exposure limit of 500 CFU/m3. While, the mean concentration of total fungi at the affected area for two buildings are 805.7 CFU/m3 and 509 CFU/m3 respectively which are both higher than the reading of outdoors and unaffected indoor area although slightly lower than the maximum exposure limit of 1000 CFU/m3. This study provides a glance of the poor indoor microbiological air quality in new higher institutional buildings in this humid region.

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Abstract. Currently, one of the main aspects of health and safety concern to facility owners and supervisors is indoor air quality. Meanwhile, pollution by airborne fungi in these facilities are acquiring more and more consideration due to its possible harmful side effects such as threats to occupiers' health and damage to building parts and furniture. One of the recommendations to solve these indoor fungi pollution is bioactive compound which can act as a biocide. However, assessment of this compound in the real environment is often time-consuming and impractical. In this study, a bioactive compound, potassium sorbate which is commonly applied in food manufacturing was assessed for its efficiency as a biocide to restrict the growth of an isolated airborne fungus using an in vitro inhibition assay. The fungus was isolated from a new building of tertiary education of computer studies. It was grown on both biocide-incorporated MEA and untreated MEA. The diameter of the fungal colonies was noted time to time. The diameter of the colony of the treated fungus was downsized by 41.25% averagely in comparison with the untreated fungus. It was shown that potassium sorbate can restrict the growth rate of the isolated airborne fungus.

Good indoor environmental quality (IEQ) is desired for a healthy indoor environment. The microbial growth in indoor environments contribute into poor indoor environmental quality can cause various of health problems. Antimicrobial coatings are designed to generate a surface that is easy to clean and can also incorporate active agents, commonly called biocides, which prevent microbial colonization, the subsequent growth and bio-deterioration of the substrate. The aim for this study is to treat indoor environmental quality in buildings by reviewing the possible application of potassium sorbate used in food industry preservatives to be use as indoor antimicrobial. Plasterboard wall was used as a substrate to see the influence of different common wall finishing used such as paints and wallpapers on fungal growth. Potassium sorbate was tested against fungal isolated from affected room M146, FKAAS building. The total fungal counts in affected room was 806 cfu/m3. The ASTM D5590-00 standard was used to evalute fungal growth and potassium sorbate was effective to inhibit the amount of fungal growth on four common types of wall finishing used on plasterboard wall. As a result, the percentage reduction in growth between control and treatment sample were 10% on thin wallpaper, 15% on acrylic paint, 25% on glycerol-based paint and 60% on thick wallpaper.

Malaysia is located on the equator has resulted in having two seasons wet and dry. Both of the seasons can influence indoor air quality of buildings promoting the growth of fungal. Fungal growth can occur with the combinations of temperature, relative humidity, substrate and others. Indoor and outdoor air quality is essential for building occupants to prevent the infection diseases caused by fungal. The goal of this study is to remediate the growth indoor fungal after treated with biocides on different types of wall finishing and evaluate the efficiencies of biocides to treat indoor fungal. In this study, the biocides are utilized as a coating for coating bio-resistance. The measurements of the fungal growth are made by growing the samples on realistic wood substrates on the different wall finishing such as paints and wallpapers. The mold that grew are affecting most of the rooms is selected. The air sampler that have been used to isolate the samples of indoor fungal according to NIOSH Manual Analytical Method (NMAM 0800), a guideline provided by National Institute of Occupational Safety and Health (NIOSH). The fungal growth was evaluated using the ASTM D5590-00 standard measuring on the surface of substrate. The results show that potassium sorbate as biocide was able to reduce the indoor fungal growth depending on the type of material used in the building.