Japareng Lalung

Removal of heavy metals and antibiotics from treated sewage effluent by bacteria

The increased loads of antibiotics and heavy metals in sewage lead to bacterial cells acquiring resistance to both heavy metals and antibiotics. Therefore, these bacteria can play an important role for removal of pollutants from sewage. The utilization of the microbial processes such as biosorption and enzymatic biodegradation processes has increased during the recent years. These processes are significantly inexpensive and eco-friendly. Enzymatic techniques known as white biotechnology have the ability to degrade complex compounds. Hence, these can be applied to industrial processes. In the current review, the removal of heavy metals and antibiotics from treated sewage effluents by heavy metal/antibiotic-resistant bacteria will be discussed.

Isolation, identification, characterization, and evaluation of cadmium removal capacity of Enterobacter species

This study focused on the isolation and characterization of high cadmium‐resistant bacterial strains, possible exploitation of its cadmium‐accumulation and cadmium‐induced proteins. Cadmium‐resistant bacterial strains designated as RZ1 and RZ2 were isolated from industrial wastewater of Penang, Malaysia. These isolates were identified as Enterobacter mori and Enterobacter sp. WS12 on the basis of phenotypic, biochemical and 16S rDNA sequence based molecular phylogenetic characteristics. Both isolates were Gram negative, cocci, and growing well in Lauria–Bertani broth medium at 35 °C temperature and pH 7.0. Results also indicated that Enterobacter mori and Enterobacter sp. WS12are capable to remove 87.75 and 85.11% of the cadmium from 100 µg ml−1 concentration, respectively. This study indicates that these strains can be useful as an inexpensive and efficient bioremediation technology to remove and recover the cadmium from wastewater.

Isolation, Identification, and Characterization of Cadmium Resistant Pseudomonas sp. M3 from Industrial Wastewater

The present study deals with the isolation, identification, and characterization of the cadmium resistant bacteria from wastewater collected from industrial area of Penang, Malaysia. The isolate was selected based on high level of the cadmium and antibiotic resistances. On the basis of morphological, biochemical characteristics, 16S rDNA gene sequencing and phylogeny analysis revealed that the strain RZCd1 was authentically identified as Pseudomonas sp. M3. The industrial isolate showed more than 70% of the cadmium removal in log phase. The cadmium removal capacity of strain RZCd1 was affected by temperature and pH. At pH 7.0 and 35°C, strain RZCd1 showed maximum cadmium removal capacity. The minimal inhibitory concentration of strain RZCd1 against the cadmium was 550 µg/mL. The resistance against the cadmium was associated with resistance to multiple antibiotics: amoxicillin, penicillin, cephalexin, erythromycin, and streptomycin. The strain RZCd1 also gave thick bands of proteins in front of 25 kDa in cadmium stress condition after 3 h of incubation. So the identified cadmium resistant bacteria may be useful for the bioremediation of cadmium contaminated industrial wastewater.

Isolation and characterization of Cd-resistant bacteria from industrial wastewater

AbstractThree bacterial strains were isolated from industrial effluents of Penang, Malaysia. The strains RZ1, RZ2, and RZ3 were identified as Pantoea sp. RL32.2, Salmonella enterica, and Enterobacter sp. OCPSB1, respectively, based on morphological observation, biochemical, physiological characterization, and 16S rDNA sequence analysis. The strains RZ1, RZ2, and RZ3 removed 89.89, 82.10, and 89.14% of cadmium, respectively, when the 100 μg/mL of cadmium was added in the medium. The minimum inhibitory concentrations of strains RZ1, RZ2, and RZ3 were 750, 410, and 550 μg/mL, respectively. Cured strain showed resistance and sensitivity against some range of antibiotics. The molecular weights of induced proteins were 35 and 25 kDa in the presence of cadmium which points out a possible role of this protein in cadmium removal. Overall, these strains could be useful for the removal of cadmium in industrial wastewater.

A Review on Biofuel and Bioresources for Environmental Applications

Microalgae are considered one of the most promising feedstocks for biofuels. Interest in algae-based biofuels and chemicals has increased over the past few years because of their potential to reduce the dependence on crude oil-based fuels and chemicals. Algae is the most suitable and sustainable feedstock for producing green energy. However, numerous challenges associated with declining fossil fuel reserves as energy sources have accounted for a shift to biofuels as alternative product from algae. Algae is a source for renewable energy production since it can fix the greenhouse gas (CO2) by photosynthesis and does not compete with the production of food. This chapter, therefore, presents a review on the prospects of algae for biofuel production and also highlighted in this article is the macroalgae-based biofuels energy products obtained from algae as the raw biomass. In a nutshell, algae are the most sustainable fuel resource in terms of environmental issues.

Utilization of Microorganisms for Biopurification of Wastewaters (Agricultural and Industrial): An Environmental Perspective

Microbial biotreatment of wastewaters is a concern in recent years. Discharge of toxic pollutants to wastewater collection systems has increased concurrently with society’s progressive industrialization. Although industrialization is inevitable, various devastating ecological and human disasters which have continuously occurred implicate industries as major contributors to pollution problems and environmental degradation of various magnitudes. Organic and inorganic substances which were released into the environment as a result of agricultural and industrial water activities lead to organic and inorganic pollution. It stands to reason that an effective treatment of these wastewaters is necessary. Microorganisms have been tested primarily as an approach for the removal of organic pollutants from wastewaters and have been proven effective at reducing chemical oxygen demand (COD) and toxicity. Biological treatment in the study provides some of the most viable options for the treatment of wastewaters. Microbial degradation of industrial wastewaters involving the application of a variety of microorganisms has demonstrated effective degradability of wastewaters which has attracted attention in recent time. The utilization of these microorganisms for bioremediation of toxic industrial wastewaters offers a very efficient tool for biopurification of contaminated effluents. Bacterial and fungal strains in this study have huge capability of treating wastewaters discharged from various industries. They are ubiquitous in nature and their adaptability to extreme conditions makes them good biodegraders. Their enzyme producing activity makes them effective decolorizers and they remove toxic metals by adsorption ultimately rendering the wastewaters more ecofriendly. Noteworthy, the bacterial and fungal biomasses present many assets for the biopurification of wastewaters.

Microbiota of Palm Oil Mill Wastewater in Malaysia

This study was aimed at identifying indigenous microorganisms from palm oil mill effluent (POME) and to ascertain the microbial load. Isolation and identification of indigenous microorganisms was subjected to standard microbiological methods and sequencing of the 16S rRNA and 18S rRNA genes. Sequencing of the 16S rRNA and 18S rRNA genes for the microbial strains signifies that they were known as Micrococcus luteus 101PB, Stenotrophomonas maltophilia 102PB, Bacillus cereus 103PB, Providencia vermicola 104PB, Klebsiella pneumoniae 105PB, Bacillus subtilis 106PB, Aspergillus fumigatus 107PF, Aspergillus nomius 108PF, Aspergillus niger 109PF and Meyerozyma guilliermondii 110PF. Results revealed that the population of total heterotrophic bacteria (THB) ranged from 9.5 × 105 – 7.9 × 106 cfu/mL. The total heterotrophic fungi (THF) ranged from 2.1 × 104 – 6.4 × 104 cfu/mL. Total viable heterotrophic indigenous microbial population on CMC agar ranged from 8.2 × 105 – 9.1 × 106 cfu/mL and 1.4 × 103 – 3.4 × 103 cfu/mL for bacteria and fungi respectively. The microbial population of oil degrading bacteria (ODB) ranged from 6.4 × 105 – 4.8 × 106 cfu/mL and the oil degrading fungi (ODF) ranged from 2.8 × 103 – 4.7 × 104 cfu/mL. The findings revealed that microorganisms flourish well in POME. Therefore, this denotes that isolating native microorganisms from POME is imperative for effectual bioremediation, biotreatment and biodegradation of industrial wastewaters.

Variation of δ2H, δ18O & δ13C in crude palm oil from different regions in Malaysia: Potential of stable isotope signatures as a key traceability parameter

A total of 33 crude palm oil samples were randomly collected from different regions in Malaysia. Stable carbon isotopic composition (δ13C) was determined using Flash 2000 elemental analyzer while hydrogen and oxygen isotopic compositions (δ2H and δ18O) were analyzed by Thermo Finnigan TC/EA, wherein both instruments were coupled to an isotope ratio mass spectrometer. The bulk δ2H, δ18O and δ13C of the samples were analyzed by Hierarchical Cluster Analysis (HCA), Principal Component Analysis (PCA) and Orthogonal Partial Least Square-Discriminant Analysis (OPLS-DA). Unsupervised HCA and PCA methods have demonstrated that crude palm oil samples were grouped into clusters according to respective state. A predictive model was constructed by supervised OPLS-DA with good predictive power of 52.60%. Robustness of the predictive model was validated with overall accuracy of 71.43%. Blind test samples were correctly assigned to their respective cluster except for samples from southern region. δ18O was proposed as the promising discriminatory marker for discerning crude palm oil samples obtained from different regions. Stable isotopes profile was proven to be useful for origin traceability of crude palm oil samples at a narrower geographical area, i.e. based on regions in Malaysia. Predictive power and accuracy of the predictive model was expected to improve with the increase in sample size. Conclusively, the results in this study has fulfilled the main objective of this work where the simple approach of combining stable isotope analysis with chemometrics can be used to discriminate crude palm oil samples obtained from different regions in Malaysia. Overall, this study shows the feasibility of this approach to be used as a traceability assessment of crude palm oils.

Detection of Microcystin (Mcye) Gene in Recreational Lakes in Miri, Sarawak, Malaysia

Toxic cyanobacteria blooms became a worldwide problems as many countries encounter the presence of the blooms in most of water bodies. As part to develop monitoring of cyanobacterial toxins in Malaysia, samples taken in twelve points in five different lakes in Miri, Sarawak. Polymerase chain reaction (PCR) amplification of cyanobacterial 16S rRNA were carried out to detect the presence of cyanobacteria in the water samples. Cyanobacterial 16S rRNA were detected in all the samples collected. While molecular analysis for detection of cyanobacterial toxin encoding gene were done using specific primers. PCR amplification of cyanobacterial toxin-encoding gene were carried using the combination of forward primer; mcyE-F2 and reverse primer; mcyE-R4 to amplify generic microcystin (mcyE) gene in the samples. Out of twelve samples collected, microcystin (mcyE) producing gene was detected in one of the samples tested. Presence of microcystin encoding gene indicates the risk of cyanobacterial toxins in Miri, Sarawak. keywords: Toxic cyanobacteria, Cyanobacterial toxins, Cyanobacterial 16S rRNA, PCR amplification, microcystin.