Annex Publishers

Aim: Palm oil processing generally generates lots of wastewater (palm oil mill effluent), this is usually discharged into the environment in the untreated form and subsequently causes several environmental issues. There is therefore need to isolate microorganisms that can be used to clean up the palm oil contaminated environment especially the soil. Methods and Results: Palm oil contaminated soil was obtained from Oba Adeyemi palm oil mill in Oyo, Oyo State, Nigeria, other soil samples which were purposely contaminated with palm oil, were obtained from Ajayi Crowther University Oyo, Oyo State. Isolation, characterization and identification of microorganisms were carried out using morphological and biochemical characterization. The isolates were preliminarily screened for lipolytic activities, this was confirmed by growth on the mineral salt medium after 7 days, signifying hydrolysis. One of the prominent isolates was further identified by sequences analysis of 16S rRNA genes. Forty-one bacterial isolates were identified, which included species of Bacillus (80 %), Pseudomonas (20 %) in the oil mill contaminated soil sample and Bacillus spp. (100 %) in the purposely contaminated soils. Twenty-nine fungal isolates including species of Aspergillus, Oidiodendron, Geotrichum, Penicillum, Saccharomyces were isolated with Aspergillus fumigatus having the highest frequency of occurrence (37.5 %) in artificially contaminated soil and Saccharomyces spp. having the highest frequency of occurrence (91 %) in palm oil contaminated soil from the palm oil mill. Sequencing of the 16S rRNA of one of the prominent isolates showed that it was identified as MN607220 Saccharomyces cerevisae. All the bacterial and fungal isolates had lipolytic activities except Bacillus mycoides and Oidiodendron sp. respectively. Nine of the ten Saccharomyces sp. had lipolytic activities. Conclusion: These screened organisms could therefore be employed for the cleanup of palm oil contamination in the environment. Significance and Impact of Study: Thereby ridding the environment of possible toxic effects especially in areas of need like Malaysia

Nickel production for electric vehicle batteries increases by 30% every year. As the country with the most nickel production in 2021, Indonesia will operate six nickel refining plants with High-pressured acid leaching technology and one development of Step Temperature Acid Leach technology. Problems arise with many hydrometallurgical-based nickel refining plants where the leach residue will continue to accumulate and potentially pollute the soil environment. Lateritic nickel leach residue has a high Fe content reaching 44.45% in the form of hematite and an S content of around 1.3%. Besides, demand growth in the iron and steel industry is greater than the availability of its raw materials. Thus, secondary sources for raw materials for the iron and steel industry are needed. The maximum S content for steel raw materials is 0.1%, so the sulfur content in leach residue must be removed. This research focuses on removing sulfur content in lateritic nickel leach residue by roasting at a temperature of 500 °C until 1100 °C. The experiment was continued with reduction roasting at various temperature profiles. The reduced phase of the roasted leach residue sample is then compared with the reduced phase of the initial leach residue sample. Sulfur content decreases with increasing roasting temperature. Sulfur content reaches ~0% at a roasting temperature of 1100 °C. The optimum initial sample reductive roasting temperature of lateritic nickel leach residue was 1400 °C with 95.9% Fe content and 0.1% S in metal. The optimum reductive roasting temperature for 1100 °C roasted samples was 1200 °C with 94.6% Fe content and 0% S. Roasting treatment can reduce the optimum temperature for the reduction roasting process.

Background: Dengue virus (DENV) infection is highly endemic in Sri Lanka with frequent epidemics. Knowledge on DENV serotype distribution will provide important information on impending epidemics. Understanding the disease burden of DENV infection during COVID-19 pandemic is highly important. Objective: To analyze the incidence of DENV infection and serotype distribution among clinically suspected patients with DENV infection during COVID-19 pandemic in Sri Lanka. Study Design: This retrospective study analyzed 1796 plasma samples from patients with clinically suspected DENV infection received at Medical Research Institute (MRI), for testing of DENV RNA, from May 2019 to April 2021. Detection of viraemia and serotypes was performed using a commercially-validated serotyping real-time Reverse Transcriptase Polymerase Chain Reaction (RT-PCR). Demographic and clinical details were recruited from accompanying request forms. Results were analyzed using descriptive statistics and chi square testing. Results: Of the samples 69.2% (n=1243) became positive for DENV RNA with 55.34% (n=688) belonging to patients under 16 years and 20.99%(n=261) to patients with severe infection. The vireamic rate ranged from 31.9% to 80.12% during different quarters of the study period. DENV-2 was detected in 40.2% (n=500) followed by DENV-3(37.97%,n=472) and DENV-1(15.44%,n=192) while co-infection with two different serotypes was observed in 5.79%(n=72). DENV3(47.5%,n=124) and DENV-2(39.46%, n=103) exhibited high percentage of positivity among patients with severe infection. Conclusions: Incidence of Dengue virus infection in Sri Lanka showed a noticeable decrease during study period. DENV2 and DENV-3 exhibited dominance with re-emergence of DENV-1 and co-infection with multiple serotypes. DENV-2 and DENV-3 were detected with severe infection predominantly.

Introduction: Isavuconazole is an antifungal drug used for treating patients with invasive fungal infections. Efficacy and safety of isavuconazole is monitored by measuring plasma isavuconazole concentration using LCMS which is a non-affordable method. We used the HPLC system with a UV detector to measure plasma Isavuconazole concentration. Objective: Improved Reversed-phase high performance liquid chromatography procedure with UV detection is described which is cost effective, simple, precise and easily processed for the measurement of Isavuconazole, a drug used to treat the patients with invasive fungal infections, in blood plasma. Method: The method involves protein precipitation, addition of ammonium dihydrogen phosphate and chromatographic separation on a Hypurity C18 Column using an isocratic mobile phase of acetonitrile and ammonium acetate buffer (pH 8.0, 10 mM) (55:45, v/v). The UV detection was performed at 285 nm. The method provides rapid resolution of Isavuconazole in a 50 uL injection. Result: Lower limit of Quantification (LLOQ) is 0.25 μg/ml in a 50 uL injection volume for Isavuconazole with a recovery consistently > 100 %. The assay is validated over linear range of 0.25 to 10 μg/ml. The intra-assay precision is < 3.53 % and inter-assay is <6.38% relative standard deviation of Isavuconazole. The method demonstrated clean separation, clinically acceptable detection limit and a linear range upto 25 ug/mL. Conclusion: The assay demonstrated applicability in quantifying the drug level and monitoring the therapeutic dose for maintaining effective biological level to have better response in fungal infected patients. The method is cheaper as compared to LC-MS/MS and Tandem Mass spectrometry and the results are reportable on the same day of blood collection.