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Fulltext Lard classification from other animal fats using Dielectric Spectroscopy technique

Amat Sairin, M., Abd Aziz, S., Tan, C.P., Mustafa, S., Abd Gani, S.S., Rokhani, F.Z.

International Food Research Journal, 2019;26(3):773-782.
MyJurnal

Lard adulteration in processed foods is a major public concern as it involves religion and
health. Most lard discriminating works require huge lab-based equipment and complex sample
preparation. The objective of the present work was to assess the feasibility of dielectric
spectroscopy as a method for classification of fats from different animal sources, in particular,
lard. The dielectric spectra of each animal fat were measured in the radio frequency of 100
Hz – 100 kHz at 45°C to 55°C. The fatty acid composition of each fat was studied by using
data from gas chromatography mass spectrometry (GCMS) to explain the dielectric behaviour
of each fat. The principal component analysis (PCA) and artificial neural network (ANN)
were used to classify different animal fats based on their dielectric spectra. It was found that
lard showed the highest dielectric constant spectra among other animal fats, and was mainly
affected by the composition of C16 and C18 fatty acids. PCA classification plot showed clear
performance in classifying different animal fats. Finally, ANN classification showed different
animal fats were classified into their respective groups effectively at high accuracy of 85%.
Dielectric spectroscopy, in combination with quantitative analysis, was concluded to provide
rapid method to discriminate lard from other animal fats.
Bioconversion of domestic wastewater sludge by immobilized mixed culture of penicillum Corylophilum WWZA1003 and Aspergillus niger SCahmA103

Alam MZ, Fakhru'l-Razi A, Idris A, Abd-Aziz S

Artif Cells Blood Substit Immobil Biotechnol, 2002 Jul;30(4):307-18.
PMID: 12227649

The bioconversion of domestic wastewater sludge by immobilized mixed culture of filamentous fungi was investigated in a laboratory. The potential mixed culture of Penicillium corylophilum WWZA1003 and Aspergillus niger SCahmA103 was isolated from its local habitats (wastewater and sludge cake) and optimized on the basis of biodegradability and dewaterability of treated sludge. The observed results in this study showed that the sludge treatment was highly influenced by the effect of immobilized mixed fungi using liquid state bioconversion (LSB) process. The maximum production of dry filter cake (DFC) was enriched with fungal biomass to about 20.05 g/kg containing 23.47 g/kg of soluble protein after 4 days of fungal treatment. The reduction of COD, TSS, turbidity (optical density against distilled water, 660 nm), reducing sugar and protein in supernatant and filtration rate of treated sludge were influenced by the fungal mixed culture as compared to control (uninnoculated). After these processes, 99.4% of TSS, 98.05% of turbidity, 76.2% of soluble protein, 98% of reducing sugar and 92.4% of COD in supernatant of treated sludge were removed. Filtration time was decreased tremendously by the microbial treatment after 2 days of incubation. The effect of fungal strain on pH was also studied and presented. Effective bioconversion was observed after 4 days of fungal treatment.
Fulltext Evaluation of single reservoir performance for flood risk reduction using a developed simulation model: case study of Makhoul reservoir

Al-Aqeeli, Yousif H., Abd Aziz, S., Wayayok, Aimrun, Badronnisa Yusuf

Pertanika Journal of Science & Technology, 2018;26(2):571-584.
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The objectives of this study were firstly, to develop a simulation model (SM) for a single reservoir to identify the standard operating policy (SOP) of a reservoir based on a monthly operating period, and secondly, to evaluate the performance of the proposed Makhoul reservoir using a Developed Simulation Model (DSM) in reducing flood risk. This reservoir is located on the River Tigris, approximately 180 km upstream of Baghdad, Iraq. The performance of the reservoir in reducing flood risk was evaluated using two designs and records of flood waves gathered over two years. The first design was the present one, while the second was developed by increasing the operational storage to its maximum, based on the digital maps of the region. The flows downstream of the reservoir were compared, with and without the reservoir in the two years in question. Four parameters resulting from the two designs were compared: storage, surface area, elevation and power. The results suggested that the reservoir would be ineffective in reducing flood risk, but it would have the ability to provide hydroelectric power using the two designs, with the new one showing better ability at doing this. The reservoir can also serve purposes such as irrigation, fish wealth development and recreation. This DSM proved its effectiveness in evaluating the performance of the single storage system used for reservoirs.
Fulltext Enhanced genetic algorithm optimization model for a single reservoir operation based on hydropower generation: case study of Mosul reservoir, northern Iraq

Al-Aqeeli YH, Lee TS, Abd Aziz S

Springerplus, 2016;5(1):797.
PMID: 27390638 DOI: 10.1186/s40064-016-2372-5

Achievement of the optimal hydropower generation from operation of water reservoirs, is a complex problems. The purpose of this study was to formulate and improve an approach of a genetic algorithm optimization model (GAOM) in order to increase the maximization of annual hydropower generation for a single reservoir. For this purpose, two simulation algorithms were drafted and applied independently in that GAOM during 20 scenarios (years) for operation of Mosul reservoir, northern Iraq. The first algorithm was based on the traditional simulation of reservoir operation, whilst the second algorithm (Salg) enhanced the GAOM by changing the population values of GA through a new simulation process of reservoir operation. The performances of these two algorithms were evaluated through the comparison of their optimal values of annual hydropower generation during the 20 scenarios of operating. The GAOM achieved an increase in hydropower generation in 17 scenarios using these two algorithms, with the Salg being superior in all scenarios. All of these were done prior adding the evaporation (Ev) and precipitation (Pr) to the water balance equation. Next, the GAOM using the Salg was applied by taking into consideration the volumes of these two parameters. In this case, the optimal values obtained from the GAOM were compared, firstly with their counterpart that found using the same algorithm without taking into consideration of Ev and Pr, secondly with the observed values. The first comparison showed that the optimal values obtained in this case decreased in all scenarios, whilst maintaining the good results compared with the observed in the second comparison. The results proved the effectiveness of the Salg in increasing the hydropower generation through the enhanced approach of the GAOM. In addition, the results indicated to the importance of taking into account the Ev and Pr in the modelling of reservoirs operation.
Fulltext Systematic Review of Brain-Eating Amoeba: A Decade Update

Ahmad Zamzuri M'I, Abd Majid FN, Mihat M, Ibrahim SS, Ismail M, Abd Aziz S, et al.

Int J Environ Res Public Health, 2023 Feb 09;20(4).
PMID: 36833715 DOI: 10.3390/ijerph20043021

INTRODUCTION: Primary amoebic meningoencephalitis (PAM) is a rare but lethal infection of the brain caused by a eukaryote called Naegleria fowleri (N. fowleri). The aim of this review is to consolidate the recently published case reports of N. fowleri infection by describing its epidemiology and clinical features with the goal of ultimately disseminating this information to healthcare personnel.
METHODS: A comprehensive literature search was carried out using PubMed, Web of Science, Scopus, and OVID databases until 31 December 2022 by two independent reviewers. All studies from the year 2013 were extracted, and quality assessments were carried out meticulously prior to their inclusion in the final analysis.
RESULTS: A total of 21 studies were selected for qualitative analyses out of the 461 studies extracted. The cases were distributed globally, and 72.7% of the cases succumbed to mortality. The youngest case was an 11-day-old boy, while the eldest was a 75-year-old. Significant exposure to freshwater either from recreational activities or from a habit of irrigating the nostrils preceded onset. The symptoms at early presentation included fever, headache, and vomiting, while late sequalae showed neurological manifestation. An accurate diagnosis remains a challenge, as the symptoms mimic bacterial meningitis. Confirmatory tests include the direct visualisation of the amoeba or the use of the polymerase chain reaction method.
CONCLUSIONS: N. fowleri infection is rare but leads to PAM. Its occurrence is worldwide with a significant risk of fatality. The suggested probable case definition based on the findings is the acute onset of fever, headache, and vomiting with meningeal symptoms following exposure to freshwater within the previous 14 days. Continuous health promotion and health education activities for the public can help to improve knowledge and awareness prior to engagement in freshwater activities.
Fulltext Combination of Superheated Steam with Laccase Pretreatment Together with Size Reduction to Enhance Enzymatic Hydrolysis of Oil Palm Biomass

Ahmad Rizal NFA, Ibrahim MF, Zakaria MR, Kamal Bahrin E, Abd-Aziz S, Hassan MA

Molecules, 2018 Apr 02;23(4).
PMID: 29614823 DOI: 10.3390/molecules23040811

The combination of superheated steam (SHS) with ligninolytic enzyme laccase pretreatment together with size reduction was conducted in order to enhance the enzymatic hydrolysis of oil palm biomass into glucose. The oil palm empty fruit bunch (OPEFB) and oil palm mesocarp fiber (OPMF) were pretreated with SHS and ground using a hammer mill to sizes of 2, 1, 0.5 and 0.25 mm before pretreatment using laccase to remove lignin. This study showed that reduction of size from raw to 0.25 mm plays important role in lignin degradation by laccase that removed 38.7% and 39.6% of the lignin from OPEFB and OPMF, respectively. The subsequent saccharification process of these pretreated OPEFB and OPMF generates glucose yields of 71.5% and 63.0%, which represent a 4.6 and 4.8-fold increase, respectively, as compared to untreated samples. This study showed that the combination of SHS with laccase pretreatment together with size reduction could enhance the glucose yield.
ACB2015: Biotechnology and bioeconomy for sustainable future

Abd-Aziz S, Faizal Ibrahim M

Biotechnol J, 2016 Jun;11(6):729-31.
PMID: 27273842 DOI: 10.1002/biot.201600156
Effect of agitation and aeration rates on chitinase production using Trichoderma virens UKM1 in 2-l stirred tank reactor

Abd-Aziz S, Fernandez CC, Salleh MM, Illias RM, Hassan MA

Appl Biochem Biotechnol, 2008 Aug;150(2):193-204.
PMID: 18633736 DOI: 10.1007/s12010-008-8140-4

Shrimps have been a popular raw material for the burgeoning marine and food industry contributing to increasing marine waste. Shrimp waste, which is rich in organic compounds is an abundant source of chitin, a natural polymer of N-acetyl-D-glucosamine (GluNac), a reducing sugar. For this respect, chitinase-producing fungi have been extensively studied as biocontrol agents. Locally isolated Trichoderma virens UKM1 was used in this study. The effect of agitation and aeration rates using colloidal chitin as control substrate in a 2-l stirred tank reactor gave the best agitation and aeration rates at 200 rpm and 0.33 vvm with 4.1 U/l per hour and 5.97 U/l per hour of maximum volumetric chitinase activity obtained, respectively. Microscopic observations showed shear sensitivity at higher agitation rate of the above system. The oxygen uptake rate during the highest chitinase productivity obtained using sun-dried ground shrimp waste of 1.74 mg of dissolved oxygen per gram of fungal biomass per hour at the kappaL a of 8.34 per hour.
Sago starch and its utilisation

Abd-Aziz S

J Biosci Bioeng, 2002;94(6):526-9.
PMID: 16233345

The importance and development of industrial biotechnology processing has led to the utilisation of microbial enzymes in various applications. One of the important enzymes is amylase, which hydrolyses starch to glucose. In Malaysia, the use of sago starch has been increasing, and it is presently being used for the production of glucose. Sago starch represents an alternative cheap carbon source for fermentation processes that is attractive out of both economic and geographical considerations. Production of fermentable sugars from the hydrolysis of starches is normally carried out by an enzymatic processes that involves two reaction steps, liquefaction and saccharification, each of which has different temperature and pH optima with respect to the maximum reaction rate. This method of starch hydrolysis requires the use of an expensive temperature control system and a complex mixing device. Our laboratory has investigated the possibility of using amylolytic enzyme-producing microorganisms in the continuous single-step biological hydrolysis of sago flour for the production of a generic fermentation medium. The ability of a novel DNA-recombinated yeast, Saccharomyces cerevisiae strain YKU 107 (expressing alpha-amylase production) to hydrolyse gelatinised sago starch production has been studied with the aim of further utilizing sago starch to obtain value-added products.