Science Heritage Journal | Galeri Warisan Sains (GWS)

Tamarix dioca (L.) belongs to family Tamaricaceae is traditionally a vital plant used for treatment of various diseases. Efforts were made to investigate the antimicrobial efficiency of T. dioca.There was three concentrations of crude methanolic extracts of 200μg/ml, 100μg/ml and 50 μg/ml were checked against six pathogenic fungi Aspergillus fumigatus, aspergillus flavus, Fusarium solani, Aspergillus niger, Penicillium digitatum and Penicillium tubesulum and six bacterial strains Bacillus subtilis, Enterobactor aerogenes, Escherichia coli, Kliebsiella pneumoniae, Salmonella typhi and Staphylococcus aureus. It was noted that Percentage inhibition in the growth of fungi and bacteria was dosage dependent. Terbinafine a standard antifungal drug, 10mg/ml and Cefexime 10mg/ml (antibacterial) were used as a positive control. The results were compared with control and most of the results were found significant. Maximum inhibition was showed by T. dioca against fungal strain A. niger (74%) and bacterial strain K. pneumoniae (48%). It can be use as powerful antimicrobial agent in near fture.

There is serious concern on noise hazard in operating theatre especially in the orthopaedics field that requires usage of many instruments. However, data on this noise exposure particularly in Malaysia is rather limited. This study was conducted as a pilot study to investigate the noise exposure in orthopaedics theatre in a hospital in Kuantan, Pahang in June 2011. Several different orthopaedics theatres involving procedures that use powered instruments were investigated. Time recorded noise exposures were taken using personal noise dosimeters throughout the surgeries worn by the surgeons. The peak noise level and the average noise exposure within 8 hours were determined, and compared with the available Factory and Machinery Act (Noise) standards. Six out of seven surgeries exceeded 140 dBA for peak sound levels. The average noise exposure within 8 hours was below 85 dBA in all cases. Although the average noise level did not surpass the stipulated guidelines, the peak level exceeding 140 dBA still carries risk for hearing loss. In conclusion, healthcare personnel in operating theatre were exposed to noise hazard for certain medical procedures. Hence, proper noise management should be implemented to protect them from noise-induced hearing loss while maintaining the success and efficiency of the surgeries.

Cucumber mosaic virus (CMV) is a plant pathogenic virus in the genus Cucumovirus, family Bromoviridae. It has the potential and reputation of having the widest host range of any known plant virus including monocotyledons and dicotyledons, herbaceous plants, shrubs and trees. CMV is one of the major diseases in Capsicum annum (chilli). Chilli plant samples exhibiting virus-like disease symptoms were collected from Taman Pertanian Indera Mahkota (location 1) and Greenhouse 12 of Horticulture Research Centre, Serdang (location 2). Viral disease was detected based on symptoms like mosaic-mottling, yellow ringspots and cholorotic that appeared on the leaves. The isolation of total RNA was done by using Vivantis GF-1 total RNA extraction kit. RT-PCR technique was used to detect the presence of virus disease symptoms gene in chillies. Identification of causal agents was based on cDNA amplified product size, using virus-specific oligonucleotides. Actin was used as the internal PCR control. The product size of the DNA fragment was 315 bp. From RT-PCR, the expression of CMV can be detected in chilli plants that exhibited the virus-like disease symptoms. This research revealed that some of the chilli plants at the Taman Pertanian Indera Mahkota and Greenhouse 12 of Horticulture Research Centre have been affected by this viral disease.

Cinnamon is one of the oldest herbal medicine that has been historically known to possess has anticancer property. In this study, the cytotoxicity of the cinnamon extracts towards human breast cancer cell line (MCF-7) was investigated. Cinnamomum zeylanicum was extracted using Soxhlet and water extraction methods, producing 7.06% and 2.54% of yield respectively. The extracts were analysed using Gas Chromatography/ Mass Spectrometry (GCMS) and it was found that cinnamaldehyde is the major constituents which contribute more than 70% of the major constituents. The cytotoxicity of C. zeylanicum extract against MCF-7 was determined through colorimetric MTT assay at 24 and 48 hours of incubation periods. The IC50 values of Soxhlet extract were 58 µg/ml and 140 µg/ml while the IC50 values of water extract were 9 mg/ml and 4.8 mg/ml, at 24 and 48 hours treatment respectively. In conclusion, C. zeylanicum extracts has been confirmed to have cytotoxic effect towards MCF-7 cell line in different concentrations at two different incubation periods.

The car manufacturers all over the globe are intensively competing among each other in terms of the design and fuel consumption factor. Nowadays the reduction of drag is becoming a very important challenge for all the car manufacturers as they are producing powerful cars with better fuel consumption in the market regulated with law reinforcement on fuel emissions and consumers. Lower drag provides better performances such as higher top speed and better stability. It also often lowers aerodynamic noise and greenhouse gas emission above all decreases in fuel consumption. However, modern designs of cars tend to go higher and wider and thus they have higher frontal areas due to the functional, economic and aesthetic requirements. Increasing frontal area of the vehicle tend to increase the drag force acting on the vehicle which is proportional to the dimensionless drag coefficient and the projected area of the vehicle. Consequently, to hold or even decrease the drag on a car that has a larger frontal area, tremendous effort has to be made. In this research both experimental and numerical analysis have been done to an existing model of a car with some various aerodynamic add-on devices that can be attached to car and reduce aerodynamic drag of the vehicle without comprising on its main design features.

Jacalin is a major lectin present in jackfruit seeds, obtained by crude protein recovery. Its lectin symbol is AIL and it belongs to the galactose family of N-acetylglucosamine binding lectins, which are recognized to be cancer cell inhibitor. There have been many pharmacological research studies focusing intensively on jacalin, however their scope was restricted to the application of jacalin in pharmacology. Jacalin or lectin extract from jackfruit seed were induced cell cycle arrest in human breast cancer cell, MCF7, in comparison of crude extract, purified jacalin and jacalin standard. IC50 for MCF7 was achieved at concentration 125 µg/mL, comparable to jacalin standard with only 1.60 % contradictions.

Surfactants have been widely used to facilitate biodegradation of petroleum pollutant; particularly those are being produced by microorganisms which are also known as biosurfactant. Six bacterial isolates from petroleum contaminated sites were found to be potential hydrocarbon degrader candidates based on their ability to grow on minimal media supplemented with petroleum crude oil as sole carbon source. In addition, they also found to be having potential in producing extracellular biosurfactant based on the results of screening for biosurfactant activity. These isolates were further identified and characterized. Morphological and biochemical characteristics of these isolates have been examined and molecular identification was done by amplifying 16S rRNA gene. Three isolates were identified as the member of the genus Pseudomonas; another two isolates were the member of genus Comamonas and one isolate from the genus Stenotrophomonas. Several qualitative screening methods (microplate assay, oil displacement test, emulsification assay and drop-collapse test) showed variation of results; suggesting the need to support these findings with quantitative screening based on measurement of surface activity. BSP 6 which was found to be closely related to Comamonas aquatica was the most promising biosurfactant producer found in this study based on two positive results out of four qualitative screening methods performed.

Polychlorinated biphenyls, PCBs are toxic, persistent organic pollutants (POP) which are harmful to human and environment due to their lipophilic characteristic and not easily degraded in the environment. Biodegradation is one of the alternative ways to reduce PCBs contamination. This study intended to isolate bacteria from landfill leachate using enrichment culture technique and optimize the growth condition of selected isolates for degradation of PCBs. PCB biodegradation efficiency by selected bacterial isolates was also determined using GC-MS. Three potential PCBs degraders were isolated from the samples of landfill leachate through enrichment culture technique, which utilised PCBs as sole carbon and energy sources but only isolate T12B shown significant effect on the degradation. Three different growth parameters were optimized involving the temperature, pH, and PCBs concentration. Central composite design (CCD) from Design Expert Software was used to design the experiment. The optimal growth condition of temperature at 37˚C with 10 ppm of PCB concentrations and pH 8 for the culture medium was achieved using Response Surface Methodology (RSM) analysis. Based on GC-MS analysis, the reduction of PCBs concentration indicates that they were utilized by isolates T12B as sole of carbon and energy sources. This may suggest that bacteria in landfill leachate play an important role in biodegradation process as well as more effective and economical.

The understanding of microorganism’s biodiversity in the peatland soil through non-cultivation based approach provide important inputs towards prediction of the ecosystem response towards the changing environment. The challenge that hindered the success to obtain high quality DNA from peat soil lies in the physicochemical characteristics such as low pH and high humic acid content. There are two general approaches that have been extensively applied for soil microbial DNA extraction, which are direct DNA extraction protocol and indirect DNA extraction protocol. The only step differentiate between these two protocols is the later includes additional cell separation method from soil micro-aggregates preceding DNA extraction process. Therefore, several improved and modified methods in conventional DNA extraction and purification methods are reviewed in this paper to cater all the highlighted issues as to obtain high-quality DNA for peatland metagenomics soil studies.

Moringa oleifera is one of the most popular plants in South Asian. It is known as miracle tree because of every parts of the plant including roots, leaves, pods flowers, and seeds containing high nutritional value and medicinal benefits. M. oleifera seed’s oil extracted contains high antioxidants properties and become as a valuable sources of protein, vitamins, beta carotene, amino acids, and various phenolic compounds. Extraction of oil and determination of antioxidants in the oil could give a great potential for commercialization especially in pharmaceutical industries due to its pharmacological properties such as antiflammatory, antihypertensive, antiepileptic, antioxidant, antibacterial and antifungal. The aim of this study were to extract the M. oleifera seeds at different extraction time and ratio of seed to solvent and determine the amount of total phenolic content (TPC) and total flavonoid content (TFC) in the methanol extract. The extraction process was carried out using Soxhlet extraction with methanol as a solvent for different ratio of seed to solvent (1:10, 1:5 and 3:10) and extraction time (2, 3, 4, 5 and 6 hours). The highest extraction yield was found at 36.84% for the seed to solvent ratio (1:10) with the extraction time of 5 hours. The highest percentages of TPC were 2027.07 (mg GAE/g of extract) at 3 hours of extraction time and seed to solvent ratio (1:10). However, the TFC values in M. oleifera seeds were 99.72 (mg QE/g of extract weight) at 5 hours of extraction time and seed to solvent ratio (1:10). The high values of TPC and TFC in methanol extract of M. oleifera seed showing it a good source of natural antioxidant and have a great potential for commercialization in food products and pharmaceutical industries.