1.Enhancement of cellulolytic enzymes and xylanase production via classical mutational techniques under solid-state fermentation condition
Tai Wan Yi ; Lee Chee Keong ; Darah Ibrahim2
Malaysian Journal of Microbiology 2016;12(1):91-101
Aims: High cost of cellulases remains the most significant barrier to the economical production of bio-ethanol from
lignocellulosic biomass (LB). The present study aims at developing a local cellulolytic fungal strain through random
mutagenesis coupled with the feasibility of solid-state fermentation (SSF) by utilizing agricultural wastes such as oil palm
frond (OPF) as the substrate.
Methodology and results: Out of 95 wild isolates tested, native fungal strain Aspergillus niger, designated DWA8 was
isolated as the top enzymatic secretor. For quantitative enzyme analysis, SSF was conducted using 1x106 spore/mL
inoculated onto 5 g of ground OPF, incubated at room temperature for 7 days, with 70% moisture content and an initial
medium pH of 7. Random mutagenesis has always been tempting in the enhancement of enzyme production. In this
work, the compounded treatment of microwave, ultraviolet (UVC) and Ethyl Methanesulfonate (EMS) have generated an
Aspergillus niger MUE3.06 mutant with an overall increase of 114% in CMCase activity, approximately 70% in FPase
and Xylanase activity respectively compared with the parental DWA8 strain. Thus this finding is capable to be fully
developed as an established mutational scheme to create highly productive filamentous fungus in a cheap, simple and
sustainable way.
Conclusion, significance and impact of study: It was the first attempt to explore the combine effect of the three
popular mutagens upon cellulases and xylanases. It is believed that more diversified of mutagen types induce more
diversified mutation pattern (with instructive planning), which is very desirable in creating new enzymes with novel
abilities.
Cellulases
2.The Effectiveness of A Floor Gully with Grating to Prevent the Oviposition of Aedes (Stegomyia) Aegypti (Linneaus): A Laboratory Study
Chen, Chee Dhang ; Teoh Pei Sze ; Wan-Norafikah Othman ; Mohd Sofian-Azirun ; Lee Han Lim.
Malaysian Journal of Health Sciences 2009;7(1):73-80
This study was conducted to evaluate the effectiveness of a floor gully come with grating to prevent the oviposition of Aedes aegypti in the floor trap. In
order to conduct the test, two containers were placed into a mosquito cage (30 cm × 30 cm × 30 cm). Both containers were filled with declorinated seasoned tap water and covered with floor gully c/w grating and normal floor
gully, respectively. A total of 50 gravid Ae. aegypti females were then released into the cage and left for a week. All the eggs obtained from the test were
allowed to remain inside the containers for the eggs to hatch. The number of hatched larvae was counted and recorded. Five replicates were conducted
concurrently. There was a significant difference of Ae. aegypti larvae obtained between container with floor gully c/w grating and normal floor gully (p <0.05). A total of 96.41% reduction of Ae. aegypti larvae was obtained in the
container with floor gully c/w grating compared with the normal floor gully, indicating that the floor gully c/w grating used in this study was able to
prevent oviposition of Ae. aegypti in holding water.
4.Proximate and biochemical analysis for marine and freshwater algae
Soopna PUSPANADAN ; Wan Maznah Wan Omar ; Lee Chee KEONG
Malaysian Journal of Microbiology 2018;14(2):137-144
Aims:In this study, ten indigenous microalgae samples from freshwater and marine waters from Malaysia, cultured and analysed on proximate and biochemical analysis. The proximate and biochemical analysis consists of starch, carbohydrates, lipid, protein, ash and moisture contents. This study was more focused on screening of starch accumulation in marine and freshwater microalgae cultures. Methodology and results:Based on screening, the results showed that Chlorella salinacontents highest starch of 4.92±0.33%, followed by Spirulinasp. 2.58±1.18%, Isochrysis maritime 0.99±0.33%, and lastly for Nitzschiapanduriformisand Naviculadistanscontents similar percentage of starch (0.44±0.10 and 0.40±0.07%, respectively). Besides starch analysis, proximate analyses(ash, moisture, lipid, protein, and carbohydrates) have been conducted. The results obtained indicated that all the cultures contain more than 4.50% of carbohydrates in average, followed by lipid and protein <1%. The results demonstrate that further optimization and various harvesting stages (early of exponential phase, early of stationary phaseand late stationary phase) may increase lipid, carbohydrates, starch, and protein accumulation. Chlorella salinaand Spirulinasp. will be used to further study on optimization of physical and chemical factors for high starch accumulation. Conclusion, significance and impact of study:In conclusion, this experiment focused more on preliminary screening for further application of starch uses in food and food packaging indust
5.Comparative insect fauna succession on indoor and outdoor monkey carrions in a semi-forested area in Malaysia
Ahmad Wasi Nazni ; Lim Han Lee ; Dhang Chee Chen ; Chin Chong Heo ; AG Abdullah ; Mustaffa Wan Wan-Norjuliana ; Kian Wai Chew ; Jeffery John ; Hashim Rosli ; Azirun Mohd Sofian
Asian Pacific Journal of Tropical Biomedicine 2011;(z2):232-238
Objective: To study the occurrence of insects fauna obtained in a semi forested area in Malaysia using the carcass of the monkey Macaca fascicularis, Raffles, and to compared the wave of insect succession collected from the carcass placed outdoor and indoor. Methods:The outdoor and indoor studies were conducted at a location of 3o17’57.86”N, 101o47’00.78”E. The euthanized monkeys were placed indoor and outdor. The insect seccession visited the carcass, the envirenmental temperature and relative humidity were recorded. Results:The main insects attracted to specific stages of decomposition were mainly members of Diptera and Coleoptera. There was a delay of fly arrival by two days in indoor carcass. Nocturnal oviposition behaviour was not observed in this study. The flies left the carcass during the twilight zone as noted during a 3 days observation period in outdoor study. The dipteran species found outdoor and indoor were similar but more diverse coleopteran species was found indoor. Conclusions:Information and evidence from this study can be used to improve the estimation of the post mortem interval in forensic cases.
6.Subjective Symptoms of Fatigue in Pharmacists.
Hai Jin LEE ; Jaek Jun KIM ; Chung Il CHUN ; Jung Wan KOO ; Chee Kyung CHUNG
Korean Journal of Occupational and Environmental Medicine 1997;9(1):26-39
In order to investigate industrial fatigue of pharmacists, the questionnaire survey for subjective symptoms and its related factors was carried out on 435 pharmacists who were managing pharmacies in Seoul. The Questionnaires were composed of three groups of 10 items each, representing dullness and sleepness(I), difficulty in concentrations (II) and bodily projection of fatigue (III). The results were as follows : 1. The complaint rate of fatigue was the highest in 'eye strain' and followed by 'whole body tires', 'apt to forget', 'leg feel heavy', 'feel drowsy' and 'feel like tying' in the descending order. 2. The average weighted score of fatigue complaint was the highest in dullness and sleepness group(I) and followed by difficulty in concentrations group(II) and bodily projection of fatigue group(III) in the descending order, suggesting the heavier mental stress rattier than physical burden of the pharmacists work contents. 3. The average weighted scores of fatigue complaints were significantly higher in female and 0-3 off-duty days per month group than those in male and more than 4 off-duty days per month group. 4. The average weighted scores of fatigue complaints were significantly different among the characteristic groups of counselling postures, noise and using chairs. 5. The groups with the high quality of sleeping, regular physical exercise and diet, or satisfied with their job and income had significantly lower average weighted scores of fatigue complaints. 6. The 42.5% of the subjects complained feeling heavy chronic fatigue. And the significant differences for average weighted scorns were noted among three groups, representing 26.64 in feeling heavy chronic fatigue, 18.23 in feeling light chronic fatigue, and 9.50 in feeling no chronic fatigue.
Diet
;
Exercise
;
Fatigue*
;
Female
;
Humans
;
Male
;
Noise
;
Pharmacies
;
Pharmacists*
;
Posture
;
Questionnaires
;
Seoul
7.The Effects of Knowledge and Attitude about Noise on Hearing Conservation Behavior and Hearing Loss .
Jung Wan KOO ; Chung Yill PARK ; Chee Kyung CHUNG ; Kang Sook LEE ; Hyeon Woo YIM ; Young Gyu PHEE ; Soon Young OH ; Wan Shik HAM
Korean Journal of Occupational and Environmental Medicine 1998;10(4):476-483
This study was conducted to investigate knowledge and attitude factor related to hearing conservation and to evaluate the effect of knowledge and attitude about noise on hearing conservation behavior and hearing loss among workers exposed to noise. We investigated the questionnaires of knowledge and attitude about noise and hearing conservation behavior and hearing loss among 355 study subjects from March, 1998 to June, 1998. The results were as follows; We extracted following 5 factors from 26 questionnaire items of knowledge and attitude about noise; knowledge of noise and concern to the control noise (factor 1), general perceived susceptibility (factor 2), relative perceived susceptibility compared with colleagues(factor 3), concern to the hearing protective devices(factor 4), concern to the hearing and noise assessment (factor 5). Knowledge and attitude factors affecting the hearing conservation behavior were general perceived susceptibility in the case of wearing hearing protective devices and knowledge of noise and concern to the control noise in the case of suggestion for hearing conservation. But, in the case of intentional avoiding noise exposure, concern to the hearing protective devices was a significant factor with concern to the hearing and noise assessment. Knowledge and attitude factors affecting hearing loss in 1 kHz were relative perceived susceptibility compared with colleagues and concern to the hearing protective devices, and in 4 KHz were relative perceived susceptibility compared with colleagues and general perceived susceptibility.
Ear Protective Devices
;
Hearing Loss*
;
Hearing*
;
Noise*
;
Questionnaires
8.Optimization of polyhydroxyalkanoate (PHA) production by Burkholderia cepacia BPT1213 utilizing waste glycerol as the sole carbon source
Nor Fauziah Mohd Zain ; Wan Nadiah Wan Abdullah ; Tan Joo SHUN ; Lee Chee KEONG ; Mohammed Razip SAMIAN
Malaysian Journal of Microbiology 2018;14(2):164-171
Aims:This study was carried out to optimize the fermentation conditions using statistical approach for polyhydroxyalkanoate(PHA) production by a local isolate, Burkholderia cepaciaBPT1213, in the shake flask system.Methodology and results:Throughout this study, B. cepaciaBPT1213 was grown in minimal salt medium (MSM) supplemented with 2% of waste glycerol (86.70% purity).The strain can produce up to 1.33 g/L cell dry weight (CDW) with 22.21% of PHA content, thus giving a total PHA concentration 0.30 g/L before optimization. A factorial design experiment that was carried out showed all parameters KH2PO4, Na2HPO4·2H2O, carbon-to-nitrogen ratio (C/N), initial pH of medium, and temperature significantly affected the growth (cell dry weight, CDW) and PHA content. Response surface methodology (RSM) using central composite design (CCD) was then applied to optimize these parameters. The optimum conditions suggested were at 2.5 g/L KH2PO4, 4.5 g/L Na2HPO4·2H2O, 30 (g/g) C/N ratio, initial medium pH of 8.5 and 37 °C cultivation temperature, with a predicted CDW of 3.43 g/L and PHA content of 45.71% contributing to 1.57 g/L total PHA concentration. The verification experiment resulted in 3.60 g/L of CDW with 48.08% of PHA content contributing to 1.73 g/L total PHA concentration.Conclusion, significance and impact of study:The statistical approach using factorial design and RSM have succeeded in increasing the production of PHA by B. cepaciaBPT1213 using waste glycerol as the sole carbon source which is a promising renewable and cheaper feedsto
9.Granular Cell Tumor Occurring in the Chest Wall: A Case Report.
Ji Young PARK ; Jae Joon HWANG ; Song Am LEE ; Woo Surng LEE ; Yo Han KIM ; Hyun Keun CHEE ; Wan Seop KIM
The Korean Journal of Thoracic and Cardiovascular Surgery 2012;45(3):196-198
Granular cell tumors are uncommon soft tissue neoplasm of nerve sheath origin, which are predominately benign. Granular cells can be found at any site in the body including the tongue, skin, subcutaneous tissue, breast, gastrointestinal, and urogenital systems. However, granular cell tumors have only been rarely described in the chest wall. Here we report a case of a granular cell tumor that occurred in the chest wall of a 59-year-old woman, along with a review of the literature.
Breast
;
Female
;
Granular Cell Tumor
;
Humans
;
Middle Aged
;
Skin
;
Soft Tissue Neoplasms
;
Subcutaneous Tissue
;
Thoracic Wall
;
Thorax
;
Tongue
;
Urogenital System
10.Health-related quality of life of patients with inflammatory bowel disease in Singapore
Prisca Yue MIN HO ; Wenjia HU ; Ying Yun LEE ; Chuxi GAO ; Yan Zhi TAN ; Hua Heng CHEEN ; Hwee Lin WEE ; Teong Guan LIM ; Wan Chee ONG
Intestinal Research 2019;17(1):107-118
BACKGROUND/AIMS: Inflammatory bowel disease (IBD) is associated with considerable impairment of patients’ health-related quality of life (HRQoL). Knowledge of factors that significantly affect IBD patients’ HRQoL can contribute to better patient care. However, the HRQoL of IBD patients in non-Western countries are limited. Hence, we assessed the HRQoL of Singaporean IBD patients and identified its determinants. METHODS: A prospective, cross-sectional study was conducted at Singapore General Hospital outpatient IBD Centre. The HRQoL of IBD patients was assessed using the short IBD questionnaire (SIBDQ), Short Form-36 physical and mental component summary (SF-36 PCS/MCS) and EuroQol 5-dimensions 3-levels (EQ-5D-3L) and visual analogue scale (VAS). Independent samples t-test was used to compare HRQoL between Crohn’s disease (CD) and ulcerative colitis (UC). Determinants of HRQoL were identified through multiple linear regression. RESULTS: A total of 195 IBD patients (103 UC, 92 CD) with a mean disease duration of 11.2 years were included. There was no significant difference in HRQoL between patients with UC and CD. Factors that significantly worsened HRQoL were presence of active disease (b=−6.293 [SIBDQ], −9.409 [PCS], −9.743 [MCS], −7.254 [VAS]), corticosteroids use (b=−7.392 [SIBDQ], −10.390 [PCS], −8.827 [MCS]), poor medication adherence (b=−4.049 [SIBDQ], −1.320 [MCS], −8.961 [VAS]), presence of extraintestinal manifestations (b=−13.381 [PCS]), comorbidities (b=−4.531 [PCS]), non-employment (b=−9.738 [MCS], −0.104 [EQ-5D-3L]) and public housing (b=−8.070 [PCS], −9.207 [VAS]). CONCLUSIONS: The HRQoL is impaired in this Asian cohort of IBD. The magnitude of HRQoL impairment was similar in UC and CD. Clinical characteristics were better determinants of patients’ HRQoL than socio-demographic factors. Recognizing the factors that impact patients’ HRQoL would improve the holistic management of IBD patients.
Adrenal Cortex Hormones
;
Asian Continental Ancestry Group
;
Cohort Studies
;
Colitis, Ulcerative
;
Comorbidity
;
Cross-Sectional Studies
;
Hospitals, General
;
Humans
;
Inflammatory Bowel Diseases
;
Linear Models
;
Medication Adherence
;
Outpatients
;
Patient Care
;
Prospective Studies
;
Public Housing
;
Quality of Life
;
Singapore