Effect of culture technique of Ganoderma australe mycelia on percentage removal of leachate organics / Wan Razarinah Wan Abdul Razak, Noor Zalina Mahmood and Noorlidah Abdullah

Leachate (liquid pollutant), which is highly contaminated with organic matter and toxic substances is a major problem that arised from landfill. Biological methods have proven to be effective to remove organic matters that are abundant in leachate. This study is intended to compare the used of free mycelia and immobilized mycelia of the white-rot fungi, Ganoderma australe for the removal of landfill leachate organics. The organics fraction of landfill leachate was measured by biological oxygen demand (BOD₅), and chemical oxygen demand (COD). The experiment revealed that free mycelia of G. australe showed capability in removing leachate BOD₅ but not COD. However, the use of immobilized G. australe displayed the best result in the removal of BOD₅ and COD leachate after 4 weeks of treatment in flasks with 93.09% and 17.84% percentage removal of BOD5 and COD, respectively. Therefore, G. australe can be considered potentially useful in the treatment of landfill leachate as they can help in removing BOD and COD due to their biodegradative abilities

Antibacterial and antibiofilm activities of Swietenia macrophylla king ethanolic extract against foodborne pathogens

Swietenia macrophylla is known to possess several medicinal uses, however, its antibacterial and antibiofilm activities against foodborne pathogens remain not well investigated. The present work was performed to examine the phytochemical compounds, antibacterial and antibiofilm activities of S. macrophylla ethanolic extract (SMEE) against four foodborne pathogens namely, Salmonella typhimurium ATCC 14028, Escherichia coli ATCC 25922, Shigella sonnei ATCC 33862 and Pseudomonas aeruginosa ATCC 10145. The phytochemical analysis of SMEE was performed using gas chromatography-mass spectrometry while the antibacterial activities of SMEE were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. On the other hand, the antibiofilm and time-killing activities of SMME were evaluated using a crystal violet assay. The result demonstrated that SMEE contained major phytochemical compounds such as olean-12-ene (27.37%), resorcinol (16.45%), 24-noroleana-3,12-diene (13.4%), and germanicol (11.50%). The MIC values of SMEE ranged from 31.25 to 500 μg/mL, while all the MBC values were found to be greater than 1000 μg/mL. At the 12 h exposure to SMEE, all the biofilms were inhibited by 50% except E. coli. Biofilm inhibitory concentration (BIC50) values of SMEE ranged between 5.19 and 42.47 μg/mL. In conclusion, S. macrophylla is a promising source of natural antibacterial and antibiofilm agents to treat foodborne diseases

Antibacterial and antibiofilm activities of Swietenia macrophylla king ethanolic extract against foodborne pathogens

Swietenia macrophylla is known to possess several medicinal uses, however, its antibacterial and antibiofilm activities against foodborne pathogens remain not well investigated. The present work was performed to examine the phytochemical compounds, antibacterial and antibiofilm activities of S. macrophylla ethanolic extract (SMEE) against four foodborne pathogens namely, Salmonella typhimurium ATCC 14028, Escherichia coli ATCC 25922, Shigella sonnei ATCC 33862 and Pseudomonas aeruginosa ATCC 10145. The phytochemical analysis of SMEE was performed using gas chromatography-mass spectrometry while the antibacterial activities of SMEE were determined by minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) assays. On the other hand, the antibiofilm and time-killing activities of SMME were evaluated using a crystal violet assay. The result demonstrated that SMEE contained major phytochemical compounds such as olean-12-ene (27.37%), resorcinol (16.45%), 24-noroleana-3,12-diene (13.4%), and germanicol (11.50%). The MIC values of SMEE ranged from 31.25 to 500 μg/mL, while all the MBC values were found to be greater than 1000 μg/mL. At the 12 h exposure to SMEE, all the biofilms were inhibited by 50% except E. coli. Biofilm inhibitory concentration (BIC50) values of SMEE ranged between 5.19 and 42.47 μg/mL. In conclusion, S. macrophylla is a promising source of natural antibacterial and antibiofilm agents to treat foodborne diseases

Isolation and characterization of polyhydroxyalkanoate (PHA)-producing, cellulolytic bacteria from municipal wastewater

Polyhydroxyalkanoates (PHA) are linear bio-esters produce in nature by certain microorganisms particularly when subjected to limited nutrients sources such as nitrogen while carbon sources are at abundance. PHA has attracted tremendous amount of attention from scientists globally due to their biodegradable property as environment-friendly alternative to petrochemical based plastics. However, the biggest drawback in using PHA is their high production cost. The aims of this study are to assess and characterise PHA-producing bacteria from municipal wastewater and compare their efficiencies in PHA production. A total of 34 out of 282 bacterial isolates from wastewater showed the ability to produce PHA using Sudan Black B staining. These isolates were then subjected to cellulase activity screen using carboxymethyl cellulose (CMC) agar. Two out of the 34 isolates were showed promising cellulose degrading capability and the cellulolytic activities were studied at 24, 48 and 72 hours of incubation respectively. The PHA production efficiencies of both isolates UiTM-E1 and UiTM-E2 were then compared using mineral salt media (MSM) supplemented with 1% and 2% glucose at 24, 48 and 72 hours of incubations respectively. Isolate UiTM-E2 showed the highest PHA production at 36.93% of its cell-dry weight (CDW) at 48 hours incubation

Performances in English Proficiency Course with Students’ Ability in Answering Higher Order Thinking Skills Questions

The English language is the medium of instruction and knowledge deliverance in Universiti Teknologi MARA (UiTM). This study looks into whether or not English writing skills affect the students’ performance in answering Higher Order Thinking Skills (HOTS) in the final examination of Molecular Biology (BIO615). The samples comprised BSc (Hons) Biology students from two consecutive semesters in two of UiTM campuses (UiTM Shah Alam and UiTM Jengka). Mean percentage between students answering the December 2015 and June 2016 final examinations in the respective campus was obtained and correlated with marks obtained in English for Academic Writing course (ELC550). The results demonstrated a weak correlation between students’ achievement in ELC550 and their ability in answering HOTS questions in BIO615 final examination in UiTM Shah Alam. In contrast, in UiTM Jengka, the moderate correlation was shown in Semester Sept-Jan 2015. The results of this study are hoped to assist biology educators in crafting appropriate and effective teaching approaches, especially in teaching complicated subjects as well as in strengthening English language proficiency.    Keywords: Higher Order Thinking Skills; Molecular Biology; English Proficiency; Bloom’s Taxonomy.    eISSN: 2398-4287 © 2020. The Authors. Published for AMER ABRA cE-Bs by e-International Publishing House, Ltd., UK. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/). Peer–review under responsibility of AMER (Association of Malaysian Environment-Behaviour Researchers), ABRA (Association of Behavioural Researchers on Asians) and cE-Bs (Centre for Environment-Behaviour Studies), Faculty of Architecture, Planning & Surveying, Universiti Teknologi MARA, Malaysia.   DOI:https://doi.org/10.21834/ebpj.v5iSI1.231

Effects of agricultural grade nutrient modulation on the biomass production and carbon fixation rate of Isochrysis sp. microalgae

This study looked at what happens when the nutrients in agricultural grade (AG) medium are changed and how that changes the biomass production and CO2 fixation ability of Isochrysis sp. It aims to address the challenges in establishing biofuel stocks due to the microalgae issue. A medium optimization system (AMOS) was first used to determine the optimum level of nitrogen, phosphorus, and micronutrients in AG medium using Factorial and Box Behnken Experimental Design, which resulted in improvements to N, K, Ca, Mg, Fe, and Z with 15 mM, 10 mM, 0.5 mM, 0.8 mM, 0.3 mM, and 0.15 mM, respectively. Subsequently, the improved medium was tested in a 1L culture volume, resulting in a 2.37 gL-1 biomass extracted from cultivation in the improved AG medium compared to cultivation in the traditional F/2 medium (1.63 gL-1). Cultures with higher Ca and Fe tested in an interim study yielded 9% and 7% enhanced biomass production compared to AG medium. The new optimized medium, which is known as TNBR-optimized medium (OM), was tested at the live coal-fired power plant in a 250 L air-lift bubbling column-type photobioreactor supplied with simulated and actual flue gas. The TNBR-optimized medium has demonstrated better algae growth, especially on actual flue gas, which has increased the concentration of CO2. The improved CO2 fixation rate was 0.72 gCO2.L-1 day-1, respectively, against those obtained from the previous report – 0.52 gCO2 L-1 day-1. An improved medium has been formulated to cultivate Isochrysis sp., and the current work can be further utilized for larger-scale cultivations

Effects of agricultural grade nutrient modulation on the biomass production and carbon fixation rate of Isochrysis sp. microalgae

This study looked at what happens when the nutrients in agricultural grade (AG) medium are changed and how that changes the biomass production and CO2 fixation ability of Isochrysis sp. It aims to address the challenges in establishing biofuel stocks due to the microalgae issue. A medium optimization system (AMOS) was first used to determine the optimum level of nitrogen, phosphorus, and micronutrients in AG medium using Factorial and Box Behnken Experimental Design, which resulted in improvements to N, K, Ca, Mg, Fe, and Z with 15 mM, 10 mM, 0.5 mM, 0.8 mM, 0.3 mM, and 0.15 mM, respectively. Subsequently, the improved medium was tested in a 1L culture volume, resulting in a 2.37 gL-1 biomass extracted from cultivation in the improved AG medium compared to cultivation in the traditional F/2 medium (1.63 gL-1). Cultures with higher Ca and Fe tested in an interim study yielded 9% and 7% enhanced biomass production compared to AG medium. The new optimized medium, which is known as TNBR-optimized medium (OM), was tested at the live coal-fired power plant in a 250 L air-lift bubbling column-type photobioreactor supplied with simulated and actual flue gas. The TNBR-optimized medium has demonstrated better algae growth, especially on actual flue gas, which has increased the concentration of CO2. The improved CO2 fixation rate was 0.72 gCO2.L-1 day-1, respectively, against those obtained from the previous report – 0.52 gCO2 L-1 day-1. An improved medium has been formulated to cultivate Isochrysis sp., and the current work can be further utilized for larger-scale cultivations