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Characteristics of developed granules containing selected decolourising bacteria for the degradation of textile wastewater

Ibrahim Z, Amin MF, Yahya A, Aris A, Muda K

Water Sci Technol, 2010;61(5):1279-88.
PMID: 20220250 DOI: 10.2166/wst.2010.021

Textile wastewater, one of the most polluted industrial effluents, generally contains substantial amount of dyes and chemicals that will cause increase in the COD, colour and toxicity of receiving water bodies if not properly treated. Current treatment methods include chemical and biological processes; the efficiency of the biological treatment method however, remains uncertain since the discharged effluent is still highly coloured. In this study, granules consisting mixed culture of decolourising bacteria were developed and the physical and morphological characteristics were determined. After the sixth week of development, the granules were 3-10 mm in diameter, having good settling property with settling velocity of 70 m/h, sludge volume index (SVI) of 90 to 130 mL/g, integrity coefficient of 3.7, and density of 66 g/l. Their abilities to treat sterilised raw textile wastewater were evaluated based on the removal efficiencies of COD (initial ranging from 200 to 3,000 mg/L), colour (initial ranging from 450 to 2000 ADMI) of sterilised raw textile wastewater with pH from 6.8 to 9.4. Using a sequential anaerobic-aerobic treatment cycle with hydraulic retention time (HRT) of 24 h, maximum removal of colour and COD achieved was 90% and 80%, respectively.
Clay-starch combination for micropollutants removal from wastewater treatment plant effluent

Mohd Amin MF, Heijman SG, Rietveld LC

Water Sci Technol, 2016;73(7):1719-27.
PMID: 27054745 DOI: 10.2166/wst.2016.001

In this study, a new, more effective and cost-effective treatment alternative is investigated for the removal of pharmaceuticals from wastewater treatment plant effluent (WWTP-eff). The potential of combining clay with biodegradable polymeric flocculants is further highlighted. Flocculation is viewed as the best method to get the optimum outcome from clay. In addition, flocculation with cationic starch increases the biodegradability and cost of the treatment. Clay is naturally abundantly available and relatively inexpensive compared to conventional adsorbents. Experimental studies were carried out with existing naturally occurring pharmaceutical concentrations found and measured in WWTP-eff with atrazine spiking for comparison between the demineralised water and WWTP-eff matrix. Around 70% of the total measured pharmaceutical compounds were removable by the clay-starch combination. The effect of clay with and without starch addition was also highlighted.
Fulltext Polyelectrolytes ability in reducing atrazine concentration in water: surface effects

Mohd Amin MF, Heijman SG, Lopes SI, Rietveld LC

ScientificWorldJournal, 2014;2014:162157.
PMID: 25197693 DOI: 10.1155/2014/162157

This paper reports on the direct ability of two positively charged organic polyelectrolytes (natural-based and synthetic) to reduce the atrazine concentration in water. The adsorption study was set up using multiple glass vessels with different polymer dosing levels followed by ultrafiltration with a 1 kDa membrane. The addition of polymers exhibited a capability in reducing the atrazine concentration up to a maximum of 60% in surface-to-volume ratio experiments. In the beginning, the theoretical L-type of the isotherm of Giles' classification was expected with an increase in the dosage of the polymer. However, in this study, the conventional type of isotherm was not observed. It was found that the adsorption of the cationic polymer on the negatively charged glass surface was necessary and influential for the removal of atrazine. Surface-to-volume ratio adsorption experiments were performed to elucidate the mechanisms and the polymer configuration. The glass surface area was determined to be a limiting parameter in the adsorption mechanism.
Characterisation of microbial flocs formed from raw textile wastewater in aerobic biofilm reactor (ABR)

Ibrahim Z, Amin MF, Yahya A, Aris A, Umor NA, Muda K, et al.

Water Sci Technol, 2009;60(3):683-8.
PMID: 19657163 DOI: 10.2166/wst.2009.440

Microbial flocs formed from raw textile wastewater in a prototype Aerobic Biofilm Reactor (ABR) system were characterised and studied for their potential use in the treatment of textile wastewater. After 90-100 days of operation, microbial flocs of loose irregular structures were obtained from the reactor with good settling velocity of 33 m/h and sludge volume index (SVI) of 48.2 mL/g. Molecular analysis of the flocs using PCR-amplified 16S rDNA sequence showed 98% homology to those of Bacillus sp, Paenibacillus sp and Acromobacter sp. Detection of Ca(2+)(131 mg/g) and Fe(2+)(131 mg/g) using atomic absorption spectrometer might be implicated with the flocs formation. In addition, presence of Co(2+) and Ni(2+) were indicative of the flocs ability to accumulate at least a fraction of the metals' present in the wastewater. When the flocs were used for the treatment of raw textile wastewater, they showed good removal of COD and colour about 55% and 70% respectively, indicating their potential application.
Fulltext The potential use of Azolla pinnata as an alternative bio-insecticide

Ravi R, Rajendran D, Oh WD, Mat Rasat MS, Hamzah Z, Ishak IH, et al.

Sci Rep, 2020 11 06;10(1):19245.
PMID: 33159109 DOI: 10.1038/s41598-020-75054-0

Four different tests showed the effectiveness of Azolla pinnata plant extracts against Aedes aegypti and Aedes albopictus mosquitoes. In the adulticidal test, there was a significant increase in mortality as test concentration increases and A. pinnata extracts showed LC50 and LC95 values of 2572.45 and 6100.74 ppm, respectively, against Ae. aegypti and LC50 and LC95 values of 2329.34 and 5315.86 ppm, respectively, against Ae. albopictus. The ovicidal test showed 100% eggs mortality for both species tested for all the concentrations tested at 1500 ppm, 1000 ppm, 500 ppm, 250 ppm and 125 ppm. Both tested samples of Ae. aegypti and Ae. albopictus did not lay any eggs in the plastic cups filled with the A. pinnata extract but instead opted to lay eggs in the plastic cups filled with water during the oviposition deterrence test. Similarly, the non-choice test of Ae. aegypti mosquitoes laid eggs on the sucrose solution meant for the nutrient source of the mosquitoes instead of in the plastic cup that was designed to facilitate oviposition filled with the extract. This clearly indicates the presence of bioactive compounds which are responsible in adulticidal and ovicidal activity in Aedes mosquitoes and at the same time inducing repellence towards the mosquitoes. The LC-MS results showed mainly three important chemical compounds from A. pinnata extracts such as 1-(O-alpha-D-glucopyranosyl)-(1,3R,25R)-hexacosanetriol, Pyridate and Nicotinamide N-oxide. All these chemicals have been used for various applications such as both emulsion and non-emulsion type of cosmetics, against mosquito vector such as Culex pipens and Anopheles spp. Finally, the overall view of these chemical components from A. pinnata extracts has shown the potential for developing natural product against dengue vectors.
Fulltext Bi-pedicled Visor Flap for Coverage of Two Skull Defects: A Practical Flap Option for Metastatic Scalp Lesions With a Favorable Cosmetic Outcome

Mohd Amin MF, Al-Chalabi MMM, Mat Johar SFN, Wan Sulaiman WA

Cureus, 2023 Jun;15(6):e40319.
PMID: 37448410 DOI: 10.7759/cureus.40319

Reconstruction of the scalp after acquired defects poses a great challenge to reconstructive surgeons. In oncologic resections, the defect must be covered with well-vascularized tissue to withstand radiotherapy post-surgery. However, due to the limited scalp tissue mobility, primary closure or loco-regional flaps are challenging and limited in choice. Fortunately, with the current understanding of the robust blood supply system to the scalp tissue, they can survive with the closure under tension. In this paper, we present a case of scalp reconstruction using a bi-pedicled visor flap to cover the two skull defects after ablative surgery. In addition, this article highlights the reason for the option, the surgical procedure, and the cosmetic outcome of the surgery.
Cultivation of Arthrospira platensis and harvesting using edible fungi isolated from mould soybean cake

Hussin AA, Hidayah Ahmad NA, Mohd Asri NF, Nik Malek NAN, Mohd Amin MF, Kamaroddin MF

Bioresour Technol, 2023 Apr;373:128743.
PMID: 36791974 DOI: 10.1016/j.biortech.2023.128743

In this study, the cultivation and harvesting of Arthrospira platensis biomass were proposed via simple, safe, and efficient techniques for direct consumption. Cultivation of microalgae in a covered macrobubble column under outdoor conditions resulted in significant differences (p
Biogenic silver nanoparticles (AgNPs) from Tinosporacordifolia leaves: An effective antibiofilm agent against Staphylococcus aureus ATCC 23235

Ghosh S, Mondol S, Lahiri D, Nag M, Sarkar T, Pati S, et al.

Front Chem, 2023;11:1118454.
PMID: 36959877 DOI: 10.3389/fchem.2023.1118454

Medicinal plants are long known for their therapeutic applications. Tinospora cordifolia (commonly called gulancha or heart-leaved moonseed plant), a herbaceous creeper widely has been found to have antimicrobial, anti-inflammatory, anti-diabetic, and anti-cancer properties. However, there remains a dearth of reports regarding its antibiofilm activities. In the present study, the anti-biofilm activities of phytoextractof T. cordifolia and the silver nanoparticles made from this phytoextract were tested against the biofilm of S.taphylococcus aureus, one of the major nosocomial infection-producing bacteria taking tetracycline antibiotic as control. Both phytoextract from the leaves of T. cordifolia, and the biogenic AgNPs from the leaf extract of T. cordifolia, were found successful in reducing the biofilm of Staphylococcus aureus. The biogenic AgNPs formed were characterized by UV- Vis spectroscopy, Field emission Scanning Electron Microscopy (FE- SEM), and Dynamic light scattering (DLS) technique. FE- SEM images showed that the AgNPs were of size ranging between 30 and 50 nm and were stable in nature, as depicted by the zeta potential analyzer. MIC values for phytoextract and AgNPs were found to be 180 mg/mL and 150 μg/mL against S. aureusrespectively. The antibiofilm properties of the AgNPs and phytoextract were analyzed using the CV assay and MTT assay for determining the reduction of biofilms. Reduction in viability count and revival of the S. aureus ATCC 23235 biofilm cells were analyzed followed by the enfeeblement of the EPS matrix to quantify the reduction in the contents of carbohydrates, proteins and eDNA. The SEM analyses clearly indicated that although the phytoextracts could destroy the biofilm network of S. aureuscells yet the biogenicallysynthesizedAgNPs were more effective in biofilm disruption. Fourier Transformed Infrared Radiations (FT- IR) analyses revealed that the AgNPs could bring about more exopolysaccharide (EPS) destruction in comparison to the phytoextract. The antibiofilm activities of AgNPs made from the phytoextract were found to be much more effective than the non-conjugated phytoextract, indicating the future prospect of using such particles for combatting biofilm-mediated infections caused by S aureus.
Larvicidal Effectiveness of Azolla pinnata against Aedes aegypti (Diptera: Culicidae) with Its Effects on Larval Morphology and Visualization of Behavioural Response

Husna Zulkrnin NS, Rozhan NN, Zulkfili NA, Nik Yusoff NR, Rasat MSM, Abdullah NH, et al.

J Parasitol Res, 2018;2018:1383186.
PMID: 30050688 DOI: 10.1155/2018/1383186

Dengue is vector-borne diseases with 390 million infections per year extending over 120 countries of the world. Aedes aegypti (L.) (Diptera: Culicidae) is a primary vector for dengue viral infections for humans. Current focus on application of natural product against mosquito vectors has been the main priority for research due to its eco-safety. The extensive use of chemical insecticides has led to severe health problems, environmental pollution, toxic hazards to human and nontarget species, and development of insecticide resistance on mosquitoes. Azolla pinnata is an aquatic fern and predominantly used as feed in poultry industry and as fertilizer in agricultural field for enhancing the fertility of rice paddy soil. The present study was conducted to explore the larvicidal efficacy of A. pinnata using fresh and powdered form against late third-stage larvae (6 days, 5 mm in larvae body length) of Ae. aegypti (L.) (Diptera: Culicidae). The larvicidal bioassays were performed using World Health Organization standard larval susceptibility test method for different concentration for powdered and fresh A. pinnata. Powdered A. pinnata concentration used during larvicidal bioassay ranges from 500ppm to 2000ppm; meanwhile, fresh A. pinnata ranges from 500ppm to 9,000,000 ppm. The highest mortality was at 1853 ppm for powdered A. pinnata compared with fresh A. pinnata at 2,521,535 ppm, while the LC50 for both powdered and fresh A. pinnata recorded at 1262 ppm and 1853 ppm, respectively. Finally, the analysis of variance (ANOVA) showed significant difference on Ae. aegypti larval mortality (F=30.439, df=1, p≤0.001) and concentration (F=20.002, df=1, p≤0.001) compared to powdered and fresh A. pinnata at 24-hour bioassay test. In conclusion, the powdered A. pinnata serves as a good larvicidal agent against Ae. aegypti (L.) (Diptera: Culicidae) and this study provided information on the lethal concentration that may have potential for a more eco-friendly Aedes mosquito control program.
Fulltext Analysis of chemical compositions and larvicidal activity of nut extracts from Areca catechu Linn against Aedes (Diptera: Culicidae)

Bharathithasan M, Ravindran DR, Rajendran D, Chun SK, Abbas SA, Sugathan S, et al.

PLoS One, 2021;16(11):e0260281.
PMID: 34843539 DOI: 10.1371/journal.pone.0260281

BACKGROUND: There is a growing need to use green alternative larvicidal control for Aedes larvae compared to chemical insecticides. Substantial reliance on chemical insecticides caused insecticide resistance in mosquito populations. Thus, research for alternate chemical compounds from natural products is necessary to control Aedes larvae. This study explores the analysis of chemical compositions from Areca catechu nut as a potential larvicide for Aedes (Diptera: Culicidae).
METHODS: The Areca catechu nut collected from Ipoh, Perak, Malaysia was grounded into powder and used for Soxhlet extraction. The chemical analysis of the extracts and their structures were identified using the GCMS-QP2010 Ultra (Shimadzu) system. National Institute of Standards and Technology (NIST) Chemistry WebBook, Standard Reference Database 69 (https://webbook.nist.gov/chemistry/) and PubChem (https://pubchem.ncbi.nlm.nih.gov/), the two databases used to retrieve the synonyms, molecular formula, molecular weight, and 2-dimensional (2D) structure of chemical compounds. Next, following WHO procedures for larval bioassays, the extracts were used to asses larvicidal activity against early 4th instar larvae of Aedes aegypti and Aedes albopictus.
RESULTS: The larvicidal activities were observed against early 4th stage larvae with different concentrations in the range from 200 mg/L to 1600 mg/L. The LC50 and LC95 of Aedes aegypti were 621 mg/L and 2264 mg/L respectively; whereas the LC50 and LC95 of Aedes albopictus were 636 mg/L and 2268 mg/L respectively. Mortality was not observed in the non-target organism test. The analysis using gas chromatography and mass spectrometer recovered several chemical compounds such as Arecaidine, Dodecanoic acid, Methyl tetradecanoate, Tetradecanoic acid , and n-Hexadecanoic acid bioactive components. These chemical constituents were used as additive formulations in pesticides, pest control, insect repellent, and insecticidal agents.
CONCLUSIONS: Our study showed significant outcomes from the extract of Areca catechu nut and it deserves further investigation in relation to chemical components and larvicidal actions between different species of Aedes mosquitoes. Even though all these findings are fundamental, it may have some interesting potentials to be developed as natural bio-larvicidal products.