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Fulltext Effectiveness of a Recertification Vision Screening Training Module for Preschool Teachers

Tan XL, Omar R, Knight VF

Malays J Med Sci, 2023 Dec;30(6):147-155.
PMID: 38239245 DOI: 10.21315/mjms2023.30.6.14

BACKGROUND: Certified training must be provided for lay vision screeners prior to their conduct of a vision screening programme. However, the effectiveness of trained lay screeners does deteriorate over time. This study aims to evaluate the effectiveness of a recertification vision screening training module using the KieVision™ Preschool Vision Screening Kit for preschool teachers in Malaysia.
METHODS: This was a randomised control trial. Fifty-nine preschool teachers previously enrolled in a Knowledge Transfer Programme were divided into a Study Group (n = 31) to receive recertification training and a Control Group (n = 28) to attend briefing sessions. Subjects was then asked to perform vision screening on 15 preschool children aged 4 years old-6 years old at their respective premises, then verified by optometrists after 2 weeks from the initial screening on the same children.
RESULTS: A total of 894 children were screened, with the Study Group and Control Group screened 49.7% and 50.3%, respectively. There was higher validity in vision screening findings from the Study Group (sensitivity = 66.7%, positive predictive value (PPV) = 61.5%) compared to the Control Group (sensitivity = 36.0 %, PPV = 40.9%).
CONCLUSION: Teachers who received recertification training were more competent in detecting children's vision impairment using KieVision™ Preschool Vision Screening Kit. Thus, timely recertification training should be emphasised to ensure sustainable consistency and reliability of vision screening programmes conducted by lay vision screeners.
Velopharyngeal and choanal stenosis after radiotherapy for nasopharyngeal carcinoma

Hussein J, Tan TS, Chong AW, Narayanan P, Omar R

Auris Nasus Larynx, 2013 Jun;40(3):323-6.
PMID: 22652485 DOI: 10.1016/j.anl.2012.05.004

Choanal stenosis is a well recognized late complication of radiotherapy for nasopharyngeal carcinoma. However velopharyngeal stenosis post radiotherapy for nasopharyngeal carcinoma is rare. We present here a case of bilateral choanal stenosis and velopharyngeal stenosis in a patient treated with radiotherapy for nasopharyngeal carcinoma. A 58-year-old woman presented to our otolaryngology clinic with a one year history of nasal obstruction. She was diagnosed to have nasopharyngeal carcinoma 12 years ago for which she received radiotherapy. Clinical examination revealed bilateral choanal stenosis and velopharyngeal stenosis. Treatment of choanal stenosis and velopharyngeal stenosis is challenging due to high incidence of recurrence and patients frequently require multiple procedures. The patient underwent a transnasal endoscopic excision of velopharyngeal scar tissue and widening of posterior choana using Surgitron®, mitomycin-C applied topically to the surgical wound and bilateral stenting under general anesthesia. The stents were kept for two weeks, and 3 years post operation velopharyngeal aperture and posterior choana remained patent. As illustrated in this case velopharyngeal stenosis can occur after radiotheraphy and should not be overlooked. Combine modality of transnasal endoscopic excision of velopharyngeal scar tissue, widening of choanal stenosis with Surgitron® followed by the application of mitomycin-C and stenting has been shown to be an effective option.
Study site: ENT clinic, University Malaya Medical Centre (UMMC), Kuala Lumpur, Malaysia
Base of tongue tuberculosis: a case report

Hussaini J, Mutusamy S, Omar R, Rajagopalan R, Narayanan P

Acta Med Iran, 2012;50(2):151-2.
PMID: 22359087

We report a rare case of base of tongue tuberculosis following pulmonary tuberculosis. Patient presented to us with chief complaints of sore throat and pain on swallowing for period of 3 months. On examination with 70 degree telescope, we observed an ulcer on right side of base of tongue. The edges of the ulcer appeared to be undermined with whitish slough at the centre of the ulcer. Examination of neck showed a multiple small palpable middle deep cervical lymph nodes on right side of neck. Biopsy of the ulcer was taken, which showed granulomatous inflammation, suggestive of tuberculosis. Laboratory investigations revealed a raise in erythrocyte sedimentation rate, sputum for acid fast bacilli was strongly positive. Chest X ray was performed for patient showed multiple areas of consolidation. Patient was referred to chest clinic for further management of tuberculosis and was started on anti-tuberculous drugs. In conclusion tuberculosis of oral cavity is rare, but should be considered among one of the differential diagnosis of the oral lesions and biopsy is necessary to confirm the diagnosis.
Management of visual disturbances in albinism: a case report

Omar R, Idris SS, Meng CK, Knight VF

J Med Case Rep, 2012;6:316.
PMID: 22992390

A number of vision defects have been reported in association with albinism, such as photophobia, nystagmus and astigmatism. In many cases only prescription sunglasses are prescribed. In this report, the effectiveness of low-vision rehabilitation in albinism, which included prescription of multiple visual aids, is discussed.
Low lying larynx

Govindaraju R, Rajagopalan R, Omar R, Mukari SA

Congenit Anom (Kyoto), 2010 Sep;50(3):193-6.
PMID: 20507348 DOI: 10.1111/j.1741-4520.2010.00280.x

We report a rare case of laryngotracheal anomaly and its possible etiology and mode of presentation. A teenager presented with voice change and a neck lump. Investigations revealed a laryngeal anomaly in which the larynx was hyperdescended. It was accompanied by low lying thyroid gland and hyoid bone together with an absence of a cervical segment of the esophagus and trachea. The anomaly only became noticeable secondary to pubertal changes in the thyroid cartilage of the teenager. An embryological defect during the formation of the laryngotracheal tube and esophagus is a possible explanation of this anomaly. The present case probably represents the third reported of its kind.
Fulltext Profile of low vision children in the special education schools in Malaysia

Omar R, Mohammed Z, Knight VF, Basrul MH

Med J Malaysia, 2009 Dec;64(4):289-93.
PMID: 20954552

This study looked at the causes of vision loss, levels of distance, near vision and the use of low vision devices (LVDs) in children studying at special schools in Malaysia. A total of 139 children from two special education schools took part. Visual acuity was measured with and without LVDs. Those who required further assessment were referred to Low Vision Clinic. Near visual acuity in 71 children ranged from N4 to N64. Sixty eight children could not read the N64 chart or they were totally blind. Only eight students were using LVDs before intervention. Seventy one children were referred for low vision assessment and 48 were found to benefit from the LVDs prescribed. The major cause of visual impairment was cataract (17%). Hand held magnifier was the most preferred LVD. Majority of the children attending the blind schools had residual vision but did not have LVDs. LVDs are able to significantly improve near visual acuity and hence there is a need to prescribe and train the children to use the LVDs.
Hearing loss after noise exposure

Govindaraju R, Omar R, Rajagopalan R, Norlisah R, Kwan-Hoong N

Auris Nasus Larynx, 2011 Aug;38(4):519-22.
PMID: 21236610 DOI: 10.1016/j.anl.2010.12.006

The higher field strength magnetic resonance imaging (MRI) such as 3 Tesla (T) and above generates noise that has potential detrimental effects on the hearing. Temporary threshold shifts following MRI examination have been reported for MRI with lower field strength. Such effect, however, have not been reported so far for a 3T MRI. We report a case that exemplifies the possible detrimental effects of a 3 T MRI generated noise on the auditory system. Our patient underwent investigation of his chronic backache in a 3 T MRI unit and developed hearing loss and tinnitus post-MRI examination. Hearing assessment was done using pure tone audiogram, distortion product otoacoustic emission (DPOAE) and brainstem electrical response audiometry (BERA) which revealed a unilateral sensorineural hearing loss which recovered within 3 days. However the tinnitus persisted. This is possibly a case of temporary threshold shift following noise exposure. However a sudden sensorineural hearing loss remains the other possibility.
Intelligent classification of electrocardiogram (ECG) signal using extended Kalman Filter (EKF) based neuro fuzzy system

Meau YP, Ibrahim F, Narainasamy SA, Omar R

Comput Methods Programs Biomed, 2006 May;82(2):157-68.
PMID: 16638620

This study presents the development of a hybrid system consisting of an ensemble of Extended Kalman Filter (EKF) based Multi Layer Perceptron Network (MLPN) and a one-pass learning Fuzzy Inference System using Look-up Table Scheme for the recognition of electrocardiogram (ECG) signals. This system can distinguish various types of abnormal ECG signals such as Ventricular Premature Cycle (VPC), T wave inversion (TINV), ST segment depression (STDP), and Supraventricular Tachycardia (SVT) from normal sinus rhythm (NSR) ECG signal.
Fulltext Inhibition of Quorum Sensing-Controlled Virulence Factors and Biofilm Formation in Pseudomonas aeruginosa by Culture Extract from Novel Bacterial Species of Paenibacillus Using a Rat Model of Chronic Lung Infection

Alasil SM, Omar R, Ismail S, Yusof MY

Int J Bacteriol, 2015;2015:671562.
PMID: 26904749 DOI: 10.1155/2015/671562

Quorum sensing (QS) is a key regulator of virulence factors and biofilm formation in Gram-negative bacteria such as Pseudomonas aeruginosa. Microorganisms that inhabit soil are of strategic importance in the discovery of compounds with anti-QS properties. The objective of the study was to test the culture extract of a taxonomically novel species of Paenibacillus strain 139SI for its inhibitory effects on the QS-controlled virulence factors and biofilm formation of Pseudomonas aeruginosa both in vitro and in vivo. The Paenibacillus sp. culture extract was used to test its anti-QS effects on the LasA protease, LasB elastase, pyoverdin production, and biofilm formation of P. aeruginosa as well as evaluate its therapeutic effects on lung bacteriology, pathology, hematological profile, and serum antibody responses of experimental animals in a rat model of chronic lung infection. Results showed significant decrease in the activities of QS-controlled LasA protease, LasB elastase pyoverdin, and biofilm formation of P. aeruginosa caused by the culture extract. Moreover, the extract significantly prolonged the survival times of rats and facilitated the clearance of biofilm infections from infected lungs. In conclusion, the antiquorum sensing effects of culture extract from a novel species of Paenibacillus provide new insights to combat biofilm-associated infections.
Production of biogas from solid organic wastes through anaerobic digestion: a review

Muhammad Nasir I, Mohd Ghazi TI, Omar R

Appl Microbiol Biotechnol, 2012 Jul;95(2):321-9.
PMID: 22622840 DOI: 10.1007/s00253-012-4152-7

Anaerobic digestion treatments have often been used for biological stabilization of solid wastes. These treatment processes generate biogas which can be used as a renewable energy sources. Recently, anaerobic digestion of solid wastes has attracted more interest because of current environmental problems, most especially those concerned with global warming. Thus, laboratory-scale research on this area has increased significantly. In this review paper, the summary of the most recent research activities covering production of biogas from solid wastes according to its origin via various anaerobic technologies was presented.
Fulltext Status of visual impairment among indigenous (Orang Asli) school children in Malaysia

Omar R, Wan Abdul WMH, Knight VF

BMC Public Health, 2019 Jun 13;19(Suppl 4):543.
PMID: 31196018 DOI: 10.1186/s12889-019-6865-3

BACKGROUND: School children are considered a high-risk group for visual impairment because uncorrected refractive errors and problems such as amblyopia can seriously affect their learning abilities and their physical and mental development. There are many studies reporting the prevalence of refractive errors among school children of different ethnic groups in Malaysia, however, studies concerning the prevalence of refractive errors among indigenous or Orang Asli children are very limited. Therefore, the objective of this study was to determine the prevalence and causes of visual impairment among Orang Asli children.
METHODS: One hundred ten Orang Asli children aged 7 to 12 years old in Negeri Sembilan, Malaysia were selected. 51% of these children were boys while the remainders were girls. They underwent visual acuity test, cover test, Hirschberg's test, ocular external assessment and ophthalmoscopy. Children who failed the vision screening were then referred for further eye examination.
RESULTS: Of these 110 Orang Asli children, 46 failed the vision screening and subsequently 45 of them were confirmed to have visual problems (40.9% of the total subjects). The main cause of visual impairment in this study was refractive error (34.5% of the total subjects) where the main refractive error found was hyperopia (28.2%) followed by amblyopia (2.7%), strabismus (1.8%) and ocular abnormalities (1.8%).
CONCLUSION: Hence, vision screening and a comprehensive eye examination is very important and needs to be done on all Orang Asli children so that any visual problems can be detect at an early stage to avoid the development of learning difficulties among these already disadvantaged children.
Fulltext Characteristics of visually impaired children in Low Vision Clinic in UKM. [Ciri kanak-kanak berpenglihatan terhad di Klinik Penglihatan Terhad UKM]

Omar R, Knight VF, Mohammed Z, Tholasee GM

Jurnal Sains Kesihatan Malaysia, 2007;5(1):37-45.
MyJurnal

While the prevalence of visually impaired children constitutes a small portion of the visually impaired population, it is important to determine whether the low vision services available are utilised by these children. This is important as previous studies have shown that children have a very high rate of successful low vision device use compared to adults. This was a cross sectional retrospective study. Fifty nine low vision clinic children records were evaluated. The results showed that 25.4% of the children were categorised as with moderate low vision, 30.5% with severe low vision and 40.7% were categorised as blind. The major causes of low vision were congenital cataract, congenital nystagmus, congenital glaucoma, macular degeneration and retinitis pigmentosa. Low vision rehabilitation for near work using magnifiers improved the vision of 30.5% of the low vision children. This finding suggests that 1/3 of low vision children could benefit from low vision rehabilitation. The low vision devices most commonly prescribed to the children in this study were stand magnifiers, hand-held magnifiers and spectacles. This study illustrates the key role of optometrists in the management of visual impairment in Malaysian children. It would appear that the establishment of low vision services in government hospitals using trained optometrists is a cost effective method of service delivery. Therefore more low vision children would have access to proper low vision rehabilitation and through that rehabilitation, their quality of life can be improved.
Key words: children, low vision
Study site: Klinik Penglihatan Terhad Pusat Perubatana, Universiti Kebangsaan Malaysia, Kuala Lumpur, Malaysia
Fulltext Antibiofilm activity, compound characterization, and acute toxicity of extract from a novel bacterial species of paenibacillus

Alasil SM, Omar R, Ismail S, Yusof MY

Int J Microbiol, 2014;2014:649420.
PMID: 24790603 DOI: 10.1155/2014/649420

The effectiveness of many antimicrobial agents is currently decreasing; therefore, it is important to search for alternative therapeutics. Our study was carried out to assess the in vitro antibiofilm activity using microtiter plate assay, to characterize the bioactive compounds using Ultra Performance Liquid Chromatography-Diode Array Detection and Liquid Chromatography-Mass Spectrometry and to test the oral acute toxicity on Sprague Dawley rats of extract derived from a novel bacterial species of Paenibacillus strain 139SI. Our results indicate that the crude extract and its three identified compounds exhibit strong antibiofilm activity against a broad range of clinically important pathogens. Three potential compounds were identified including an amino acid antibiotic C8H20N3O4P (MW 253.237), phospholipase A2 inhibitor C21H36O5 (MW 368.512), and an antibacterial agent C14H11N3O2 (MW 253.260). The acute toxicity test indicates that the mortality rate among all rats was low and that the biochemical parameters, hematological profile, and histopathology examination of liver and kidneys showed no significant differences between experimental groups (P > 0.05). Overall, our findings suggest that the extract and its purified compounds derived from novel Paenibacillus sp. are nontoxic exhibiting strong antibiofilm activity against Gram-positive and Gram-negative pathogens that can be useful towards new therapeutic management of biofilm-associated infections.
Validity of vision screening program conducted by preschool teachers: An interventional study

Mezbah U, Omar R, Md Isa Z, Knight VF

Med Hypothesis Discov Innov Ophthalmol, 2022;11(1):1-10.
PMID: 37641697 DOI: 10.51329/mehdiophthal1439

BACKGROUND: Clear vision is crucial for effective learning among preschool children. Hence, early detection of vision impairment and prompt treatment are required to improve prognosis. Currently, limited information is available, and no program exists to screen for vision impairment among preschoolers in Bangladesh. This study aimed to validate the KieVision™ Preschool Vision Screening Kit, translated into the Bengali language, to improve vision impairment detection among preschool children.
METHODS: In this prospective case-control study, 60 preschool teachers from Chittagong were randomly selected. The study group was trained to conduct vision screening among preschool children using the translated kit, whereas the control group was trained using the Chittagong Eye Infirmary and Training Complex (CEITC) School Teachers' Training Module. Fifteen preschool children aged 4-6 years were screened by each preschool teacher and again by the optometrist.
RESULTS: Sixty preschool teachers screened 900 children. The results showed a higher validity of vision screening findings by the preschool teachers in the study group (sensitivity, 68.00%; specificity, 92.75%) than in the control group (sensitivity 47.37%, specificity 70.39%). The level of agreement between the preschool teachers and optometrists was high for all tests (first-order agreement coefficient [AC1] ≥ 0.80 in the study group). The sensitivity and specificity of the visual acuity test for the study group were 59.65% and 94.15%, respectively, while in the control group it was 13.33% and 62.54%, respectively. A similar trend was noted in the general observation component and Hirschberg's test.
CONCLUSIONS: The Bengali Language KieVision™ Preschool Vision Screening Kit can be used effectively by preschool teachers in vision screening programs to improve the identification of vision impairment among preschool children in Bangladesh.
Fulltext Mental health state and quality of life questionnaire in low vision assessment: a case report

Omar R, Rahman MH, Knight VF, Mustaphal M, Mohammed Z

BMC Res Notes, 2014;7:667.
PMID: 25245590 DOI: 10.1186/1756-0500-7-667

BACKGROUND: Vision impairment associated with diabetic retinopathy, is well known and low vision rehabilitation is always recommended. In this report, the importance of objective measure of mental health and quality of life screening in diabetic retinopathy low-vision assessment is discussed.
CASE PRESENTATION: We describe the case of a 43-year-old Asian female who has mild vision impairment due to tractional retinal detachment secondary to diabetic retinopathy and how mental health screening and quality of life screening during low vision rehabilitation can improve in the management of this patient.
CONCLUSION: Although vision impairment was mild, the psychological impact was enormous and affected her quality of life substantially. This case report illustrates that recognition of the mental health and quality of life impact on visual impairment is critical to the rehabilitation management of low vision patients with diabetic retinopathy.
A single centre experience of the efficacy and safety of dabigatran etexilate used for stroke prevention in atrial fibrillation

Yap LB, Rusani BI, Umadevan D, Muhammad Z, Hussin A, Kaur S, et al.

J Thromb Thrombolysis, 2014 Jul;38(1):39-44.
PMID: 24197653 DOI: 10.1007/s11239-013-1020-y

The use of novel anticoagulants such as dabigatran are increasing. Despite increased risks of intracerebral haemorrhage with warfarin among Asians, there is little published data on dabigatran to assess 'real world' efficacy and safety of dabigatran therapy in Asia. This was a retrospective observational study of patients prescribed dabigatran between 2010 and 2013. Data was available for 510 patients: median age 68 years (range 20-91), median CHA2DS2-VASc score was 2 and median HAS-BLED score was 2. The average follow-up duration of 315 days (range: 1-1,096). The overall discontinuation rate was 16% after a median 252 days of treatment with dabigatran. There were 17 (3.3%) patients with minor bleeding, 2 (0.4%) had major bleeding episodes. 20 patients (3.9%) developed dyspepsia which was the most common side effect. The rate of occurrences of adverse effects and bleeding were lower than those seen in the RE-LY trial. None of the patients had an ischaemic stroke, 1 (0.2%) patient had a haemorrhagic stroke. Out of 510 patients, 158 patients (31%) were switched to dabigatran from warfarin. This showed that patients frequently preferred the dabigatran due to convenience when given a choice to switch from warfarin. We report one of the largest registry of Asian patients. Reassuringly, we found that our cohort had a low rate of rate of ischaemic stroke, low rates of side effects and bleeding with the drug.
Fulltext An international observational prospective survey assessing the control of atrial fibrillation in Asia-Pacific: results of the Record-AFAP Registry

Amerena J, Chen SA, Sriratanasathavorn C, Cho JG, Dejia H, Omar R, et al.

Clin Med Insights Cardiol, 2015;9:77-83.
PMID: 26279634 DOI: 10.4137/CMC.S22022

A prospective 1-year observational survey was designed to assess the management and control of atrial fibrillation (AF) in eight countries within the Asia-Pacific region. Patients (N = 2,604) with recently diagnosed AF or a history of AF ≤1 year were included. Clinicians chose the treatment strategy (rhythm or rate control) according to their standard practice and medical discretion. The primary endpoint was therapeutic success. At baseline, rhythm- and rate-control strategies were applied to 35.7% and 64.3% of patients, respectively. At 12 months, therapeutic success was 43.2% overall. Being assigned to rhythm-control strategy at baseline was associated with a higher therapeutic success (46.5% vs 41.4%; P = 0.0214) and a lower incidence of clinical outcomes (10.4% vs 17.1% P < 0.0001). Patients assigned to rate-control strategies at baseline had higher cardiovascular morbidities (history of heart failure or valvular heart disease). Cardiovascular outcomes may be less dependent on the choice of treatment strategy than cardiovascular comorbidities.
Fulltext An acceleration of microwave-assisted transesterification of palm oil-based methyl ester into trimethylolpropane ester

Aziz NAM, Yunus R, Hamid HA, Ghassan AAK, Omar R, Rashid U, et al.

Sci Rep, 2020 11 12;10(1):19652.
PMID: 33184363 DOI: 10.1038/s41598-020-76775-y

Microwave-assisted synthesis is known to accelerate the transesterification process and address the issues associated with the conventional thermal process, such as the processing time and the energy input requirement. Herein, the effect of microwave irradiation on the transesterification of palm oil methyl ester (PME) with trimethylolpropane (TMP) was evaluated. The reaction system was investigated through five process parameters, which were reaction temperature, catalyst, time, molar ratio of TMP to PME and vacuum pressure. The yield of TMP triester at 66.9 wt.% and undesirable fatty soap at 17.4% were obtained at 130 °C, 10 mbar, sodium methoxide solution at 0.6 wt.%, 10 min reaction time and molar ratio of TMP to PME at 1:4. The transesterification of palm oil-based methyl ester to trimethylolpropane ester was 3.1 folds faster in the presence of microwave irradiation. The total energy requirement was markedly reduced as compared to the conventional heating method. The findings indicate that microwave-assisted transesterification could probably be an answer to the quest for a cheaper biodegradable biolubricant.
Fulltext Photovoltaic modules evaluation and dry-season energy yield prediction model for NEM in Malaysia

Islam SZ, Othman ML, Saufi M, Omar R, Toudeshki A, Islam SZ

PLoS One, 2020;15(11):e0241927.
PMID: 33180779 DOI: 10.1371/journal.pone.0241927

This study analyzes the performance of two PV modules, amorphous silicon (a-Si) and crystalline silicon (c-Si) and predicts energy yield, which can be seen as facilitation to achieve the target of 35% reduction of greenhouse gases emission by 2030. Malaysia Energy Commission recommends crystalline PV modules for net energy metering (NEM), but the climate regime is a concern for output power and efficiency. Based on rainfall and irradiance data, this study aims to categorize the climate of peninsular Malaysia into rainy and dry seasons; and then the performance of the two modules are evaluated under the dry season. A new mathematical model is developed to predict energy yield and the results are validated through experimental and systematic error analysis. The parameters are collected using a self-developed ZigBeePRO-based wireless system with the rate of 3 samples/min over a period of five days. The results unveil that efficiency is inversely proportional to the irradiance due to negative temperature coefficient for crystalline modules. For this phenomenon, efficiency of c-Si (9.8%) is found always higher than a-Si (3.5%). However, a-Si shows better shadow tolerance compared to c-Si, observed from a lesser decrease rate in efficiency of the former with the increase in irradiance. Due to better spectrum response and temperature coefficient, a-Si shows greater performance on output power efficiency (OPE), performance ratio (PR), and yield factor. From the regression analysis, it is found that the coefficient of determination (R2) is between 0.7179 and 0.9611. The energy from the proposed model indicates that a-Si yields 15.07% higher kWh than c-Si when luminance for recorded days is 70% medium and 30% high. This study is important to determine the highest percentage of energy yield and to get faster NEM payback period, where as of now, there is no such model to indicate seasonal energy yield in Malaysia.
Fulltext Hydrolysis and characterization of sugar recovery from bakery waste under optimized subcritical water conditions

Mohd Thani N, Mustapa Kamal SM, Taip FS, Sulaiman A, Omar R, Siajam SI

J Food Sci Technol, 2020 Aug;57(8):3108-3118.
PMID: 32612303 DOI: 10.1007/s13197-020-04345-1

Subcritical water hydrolysis process for sugar recovery from leftover croissants (LC) and leftover doughnuts (LD) was optimised using response surface methodology with three process parameters as dependent variables and sugar yield as the response. The process parameters: temperature (160-200 °C), time (5-15 min), and solid loading (10-50%), on the sugar yield were investigated. For the LC sample, the optimised process conditions were determined to be: 200 °C, 6.17 min, and 10% solid loading producing an 80% hydrolysis yield of 466.11 ± 0.67 mg/g. Comparatively, the LD sample optimisation parameters were: 200 °C, 5 min, and 10% solid loading producing a 76.18% hydrolysis yield of 394.34 ± 0.33 mg/g. The sugar extracts were further characterise; which through scanning electron microscopy revealed the LC had most starch granules rupture during hydrolysis, while Fourier-transform infrared spectroscopy detected the presence of monosaccharides and oligosaccharides for both LC and LD. 5-hydroxymethylfurfural (5-HMF), a sugar degradation by-product, was also detected with 39.16 ± 0.61 and 20.59 ± 0.81 mg/g for the LC and LD, respectively, at optimal conditions.

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