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Photocytotoxic pheophorbide-related compounds from Aglaonema simplex

Chee CF, Lee HB, Ong HC, Ho AS

Chem Biodivers, 2005 Dec;2(12):1648-55.
PMID: 17191961

In our screening program for new photosensitizers from the Malaysian biodiversity, we found five pheophorbide-related compounds from the leaves and stems of Aglaonema simplex. Detailed spectroscopic analyses showed that compounds 1-3 and 5 are pheophorbide and hydroxy pheophorbide derivatives of chlorophyll a and b. Compound 4, identified as 15(1)-hydroxypurpurin-7-lactone ethyl methyl diester, was isolated for the first time from the Araceae family. An MTT-based short-term survival assay showed that all five compounds exhibit moderate-to-strong photocytotoxic activities towards human leukemia (HL60) and two oral squamous carcinoma cell lines (HSC-2 and HSC-3). Compounds 4 and 5 showed the strongest photocytotoxicities, with IC(50) values of 0.30-0.41 muM (Table 2). Compounds 1-3 with Et chains at C(17(3)) were less photocytotoxic than the parent pheophorbide a (5).
Perspectives on cultivation and harvesting technologies of microalgae, towards environmental sustainability and life cycle analysis

Soudagar MEM, Kiong TS, Jathar L, Nik Ghazali NN, Ramesh S, Awasarmol U, et al.

Chemosphere, 2024 Apr;353:141540.
PMID: 38423144 DOI: 10.1016/j.chemosphere.2024.141540

The development of algae is seen as a potential and ecologically sound approach to address the increasing demands in multiple sectors. However, successful implementation of processes is highly dependent on effective growing and harvesting methods. The present study provides a complete examination of contemporary techniques employed in the production and harvesting of algae, with a particular emphasis on their sustainability. The review begins by examining several culture strategies, encompassing open ponds, closed photobioreactors, and raceway ponds. The analysis of each method is conducted in a systematic manner, with a particular focus on highlighting their advantages, limitations, and potential for expansion. This approach ensures that the conversation is in line with the objectives of sustainability. Moreover, this study explores essential elements of algae harvesting, including the processes of cell separation, dewatering, and biomass extraction. Traditional methods such as centrifugation, filtration, and sedimentation are examined in conjunction with novel, environmentally concerned strategies including flocculation, electro-coagulation, and membrane filtration. It evaluates the impacts on the environment that are caused by the cultivation process, including the usage of water and land, the use of energy, the production of carbon dioxide, and the runoff of nutrients. Furthermore, this study presents a thorough examination of the current body of research pertaining to Life Cycle Analysis (LCA) studies, presenting a perspective that emphasizes sustainability in the context of algae harvesting systems. In conclusion, the analysis ends up with an examination ahead at potential areas for future study in the cultivation and harvesting of algae. This review is an essential guide for scientists, policymakers, and industry experts associated with the advancement and implementation of algae-based technologies.
Fulltext Pattern of heart disease and pregnancy seen in a Malaysian hospital

Ong HC, Puraviappan AP, Sinnathuray TA, Chong CH, Sen DK

Singapore Med J, 1978 Jun;19(2):93-7.
PMID: 751193

Pregnancy was associated with cardiac disease in 0.94% of pregnancies. 0.66% with rheumatic lesions and 0.25'\'0 with congenital lesions. The Malays had a higher incidence than the Chinese and Indians. Most of the cardiac pregnancies were in patients between 20-30 years of age and gravida 1 to 4. Nevertheless. still about 30% of cardiac pregnancies were in patients 30 years and over in age and 20% in patient gravida 5 and above. Rheumatic lesions predominated. involving mainly the mitral valve. of which the major lesion was mitral stenosis. PDA. ASD and VSD were the major congenital lesions. Major antepartum matemal complications included arrhythmias. heart failure, anemia and pre-eclampsia. Of the arrhythmias. atrial fibrillation and sinus tachycardia occurred most commonly. A high incidence of prophylactic forceps and vacuum deliveries
was evident. There was one matemal death. The majority of infants were bom alive and well.
Partial exchange transfusion in the treatment of severe anaemia in late pregnancy

Ong HC, Chan WF, Hussein N

Med J Malaysia, 1975 Sep;30(1):63-65.
PMID: 1207535
Oxidative torrefaction performance of microalga Nannochloropsis Oceanica towards an upgraded microalgal solid biofuel

Zhang C, Ho SH, Chen WH, Wang R, Show PL, Ong HC

J Biotechnol, 2021 Sep 10;338:81-90.
PMID: 34298023 DOI: 10.1016/j.jbiotec.2021.07.009

Microalgae are a promising feedstock for carbon-neutral biofuel production due to their superior cellular composition. Alternatively, oxidative torrefaction has been recognized as a potential thermochemical technique for microalgal solid biofuel upgrading. Herein, by using microalga N. oceanica as a feedstock, several characterizations are adopted for evaluating the potential of oxidative torrefaction towards microalgal solid biofuel production. The oxidatively torrefied microalgae can be upgraded as lignite. After in-depth analysis, significant change in the surface microstructure of oxidatively torrefied microalgae is largely changed (via wrinkle and fragmentation) The hydrophobicity, thermal decomposition, thermal stability, and aromatization of oxidatively torrefied microalgae can be largely enhanced as the oxidative torrefaction severity increase. With the increasing torrefaction temperature, the hydrophobicity of oxidative torrefied microalgae gradually improved. The decomposition of C-2/3/5, and -OCH3, the CO bonds of CH3CO-, and the aromatization occurs via oxidative torrefaction according to the NMR analysis. For XPS analysis, torrefaction operation significantly decreases the carbide carbon and enhances the graphitization. As a result, the thermal stability of oxidatively torrefied microalgae is improved. Conclusively, the information obtained in this study can provide insights into the evaluation of oxidative torrefaction performance and fuel properties of microalgal solid biofuel, which may help accelerate the advancement of oxidative torrefaction industrialization.
Onset of labour

Chong HL, Ong HC, Ang LT

Med J Malaysia, 1974 Sep;29(1):44-53.
PMID: 4282630
Obstetrical data in Malaysian aborigine women

Ong HC

Trop Geogr Med, 1974 Dec;26(4):384-8.
PMID: 4456697
Novel bufferless photosynthetic microbial fuel cell (PMFCs) for enhanced electrochemical performance

Wang CT, Huang YS, Sangeetha T, Chen YM, Chong WT, Ong HC, et al.

Bioresour Technol, 2018 May;255:83-87.
PMID: 29414177 DOI: 10.1016/j.biortech.2018.01.086

Photosynthetic microbial fuel cells (PMFCs) are novel bioelectrochemical transducers that employ microalgae to generate oxygen, organic metabolites and electrons. Conventional PMFCs employ non-eco-friendly membranes, catalysts and phosphate buffer solution. Eliminating the membrane, buffer and catalyst can make the MFC a practical possibility. Therefore, single chambered (SPMFC) were constructed and operated at different recirculation flow rates (0, 40 and 240 ml/min) under bufferless conditions. Furthermore, maximum power density of 4.06 mW/m2, current density of 46.34 mA/m2 and open circuit potential of 0.43 V and low internal resistance of 611.8 Ω were obtained at 40 ml/min. Based on the results it was decided that SPMFC was better for operation at 40 ml/min. Therefore, these findings provided progressive insights for future pilot and industrial scale studies of PMFCs.
Mucinous cystadenoma, serous cystadenoma and benign cystic teratoma of the ovary: clinico-pathologic differences observed in a Malaysian hospital

Ong HC, Chan WF

Cancer, 1978 Apr;41(4):1538-42.
PMID: 639009

A study of 207 benign ovarian tumors seen at the University Hospital, Kuala Lumpur between 1968 and 1975 was made to evaluate the clinical features that might be useful in the preoperative differentiation of mucinous cystadenoma, serous cystadenoma, and cystic teratoma of the ovary. This study indicated that the pertinent information included the mean age of the patient, the marital and menstrual status, and the estimated tumor size. The racial background was an additional factor in serous cystadenoma. Features like parity, the location of the tumor, and ABO blood group pattern were of no value in the preoperative differentiation.
Migration in Malaysian aborigines: clinical observations in pregnancy

Ong HC

Southeast Asian J. Trop. Med. Public Health, 1975 Sep;6(3):407-412.
PMID: 1221499

This study presents clinical observations in pregnancy made on aborigines of the deep jungle and "outside" populations. Migration out of the jungle results in lowered nutritional status as a result of low socio-economic status in the "outside" aborigine. This, together with food habits, increased family size and higher incidence of helminthic infestations, results in lower mean values of Hb, PVC and MCHC and a higher prevalence of anaemia in pregnancy in the migrant aborigine. A higher population density in the "outside" population resulting in frequent intermingling and increased chances of cross-contamination probably explains the increased vaginal bacterial growth in the "outside" Aborigine women. A higher prevalence of vaginal candidiasis in the "outside" aborigine woman is probably related to exposure to oral contraceptives and broad-spectrum antibiotics. On the other hand, better medical and obstetrical services become more readily available to the "outside" aborigine and this results in a favourable influence on perinatal health.
Investigation of antibacterial mechanism and identification of bacterial protein targets mediated by antibacterial medicinal plant extracts

Yong AL, Ooh KF, Ong HC, Chai TT, Wong FC

Food Chem, 2015 Nov 1;186:32-6.
PMID: 25976788 DOI: 10.1016/j.foodchem.2014.11.103

In this paper, we investigated the antibacterial mechanism and potential therapeutic targets of three antibacterial medicinal plants. Upon treatment with the plant extracts, bacterial proteins were extracted and resolved using denaturing gel electrophoresis. Differentially-expressed bacterial proteins were excised from the gels and subjected to sequence analysis by MALDI TOF-TOF mass spectrometry. From our study, seven differentially expressed bacterial proteins (triacylglycerol lipase, N-acetylmuramoyl-L-alanine amidase, flagellin, outer membrane protein A, stringent starvation protein A, 30S ribosomal protein s1 and 60 kDa chaperonin) were identified. Additionally, scanning electron microscope study indicated morphological damages induced on bacterial cell surfaces. To the best of our knowledge, this represents the first time these bacterial proteins are being reported, following treatments with the antibacterial plant extracts. Further studies in this direction could lead to the detailed understanding of their inhibition mechanism and discovery of target-specific antibacterial agents.
In vitro antidermatophytic activity and cytotoxicity of extracts derived from medicinal plants and marine algae

Sit NW, Chan YS, Lai SC, Lim LN, Looi GT, Tay PL, et al.

J Mycol Med, 2018 Sep;28(3):561-567.
PMID: 30060991 DOI: 10.1016/j.mycmed.2018.07.001

OBJECTIVES: This study was conducted to evaluate the antidermatophytic activity of 48 extracts obtained from medicinal plants (Cibotium barometz, Melastoma malabathricum, Meuhlenbeckia platyclada, Rhapis excelsa, Syzygium myrtifolium, Vernonia amygdalina) and marine algae (Caulerpa sertularioides, Kappaphycus alvarezii) against Trichophyton rubrum and Trichophyton interdigitale (ATCC reference strains), and the cytotoxicity using African monkey kidney epithelial (Vero) cells. Active plant extracts were screened for the presence of phytochemicals and tested against clinical isolates of Trichophyton tonsurans.
METHODS: Six different extracts (hexane, chloroform, ethyl acetate, ethanol, methanol and water) were obtained from each plant or algae sample using sequential solvent extraction. The antidermatophytic activity for the extracts was assessed using a colourimetric broth microdilution method. The viability of Vero cells was measured by Neutral Red uptake assay.
RESULTS: All the extracts (except the water extracts of V. amygdalina, C. sertularioides and K. alvarezii) showed antidermatophytic activity against Trichophyton spp. The minimum fungicidal concentration (MFC) ranges for the plant extracts against T. rubrum and T. interdigitale are 0.0025-2.50 and 0.005-2.50mg/mL, respectively. The algae extracts exhibited lower potency against both species, showing MFC ranges of 0.08-2.50 and 0.31-2.50mg/mL, respectively. The ethanol and methanol extracts from the leaves of R. excelsa, and the methanol and water extracts from the leaves of S. myrtifolium were highly active (MFC<0.1mg/mL) and with high selectivity indices (SI>2.8) against reference strains of T. rubrum and T. interdigitale, and most of the clinical isolates of T. tonsurans. Phytochemical analysis indicates the presence of alkaloids, anthraquinones, flavonoids, saponins, tannins, phenolics and triterpenoids in the extracts.
CONCLUSIONS: The medicinal plant extracts exhibited stronger antidermatophytic activity compared to the algae extracts. The leaves of R. excelsa and S. myrtifolium are potential sources of new antidermatophytic agents against Trichophyton spp.
Identification of Potential Anticancer Protein Targets in Cytotoxicity Mediated by Tropical Medicinal Fern Extracts

Tan ST, Ong HC, Chai TT, Wong FC

Pharmacogn Mag, 2018 04 10;14(54):227-230.
PMID: 29720836 DOI: 10.4103/pm.pm_282_17

Background: Medicinal fern species represent a potentially important source for both food and medicinal applications. Previously, two underutilized tropical fern species (Blechnum orientale and Phymatopteris triloba) were reported with cytotoxic activities against selected cancer cell lines. However, the exact mechanism remains elusive.
Objective: In this paper, we reported the identification of six differentially expressed proteins isolated from cancer cells, following exposure to the cytotoxic fern extracts.
Materials and Methods: The identities of these cancer proteins were determined by matrix-assisted laser desorption ionization time-of-flight protein sequencing.
Results: The cancer proteins were identified as follows: elongation factor 1-γ, glyceraldehydes-3-phosphate dehydrogenase, heat shock protein 90-β, heterogeneous nuclear ribonucleoprotein-A2/B1, truncated nucleolar phosphoprotein B23, and tubulin-β chain. To the best of our knowledge, this paper represents the first time these cancer proteins are being reported, following exposure to the aforementioned cytotoxic fern extracts.
Conclusion: It is hoped that further efforts in this direction could lead to the identification and development of target-specific chemotherapeutic agents.
SUMMARY: Cytotoxic fern extracts were tested in anti-cancer proteomic works.Six differentially-expressed cancer proteins were identified.Potential anti-cancer protein targets were reported. Abbreviations used: EF: Elongation factor; HRP: Horseradish peroxidase; HSP: Heat shock protein; MALDI: Matrix-assisted laser desorption/ionization.
Human placental lactogen physiological role in pregnancy

Ong HC

Med J Malaysia, 1976 Mar;30(3):165-7.
PMID: 958050
Fulltext High performance liquid chromatography profiling of health-promoting phytochemicals and evaluation of antioxidant, anti-lipoxygenase, iron chelating and anti-glucosidase activities of wetland macrophytes

Ooh KF, Ong HC, Wong FC, Sit NW, Chai TT

Pharmacogn Mag, 2014 Aug;10(Suppl 3):S443-55.
PMID: 25298659 DOI: 10.4103/0973-1296.139767

The phytochemistry and bioactivity of wetland macrophytes are underexplored. Plants are known as the natural sources of phytochemical beneficial to health.
Hematological values in pregnancy in Orang Asli (aboriginal) women

Ong HC

Med J Malaysia, 1973 Jun;27(4):240-2.
PMID: 4270778
Haemoglobin H disease and pregnancy in a Malaysian woman

Ong HC, White JC, Sinnathuray TA

Acta Haematol., 1977;58(4):229-33.
PMID: 410224 DOI: 10.1159/000207832

A case of haemoglobin H (HbH) disease associated with pregnancy is presented and discussed in the light of reports in the literature. The variable symptomatology is commented upon, although mild to moderate chronic haemolytic anaemia seems to be a constant feature. The roles of folic acid supplements and of splenectomy; the avoidance of oxidant drugs, and the mode of inheritance in HbH disease are briefly commented upon. Available reports indicate that HbH disease probably has no adverse effect on pregnancy. However, the association of the two conditions is uncommon, and reports are too few, therefore, to allow definite conclusions on the outcome in all instances.
Haemoglobin E variants and pregnancy in Malaysian aborigines

Ong HC

Acta Haematol., 1974;52(4):220-2.
PMID: 4217527 DOI: 10.1159/000208244

Haemoglobin E complicates 22.2°/o of pregnancy in Malaysian aborigines, the prevalence of variants associated with pregnancy being, 15.8% with Hb E trait abnormality, 3.9% with Hb E homozygous disease, and 2.5% with Hb E thalassaemia disease. Minor haematological abnormalities occur with the trait and homozygous conditions, though a more unfavourable response is expected with Hb E thalassaemia. Haemolysis is not a prominent feature and it is suggested that factors other than the haemoglobinopathic state
probably accounts for any unfavourable response in pregnancy.
Key Words: Haemoglobin E; Haemoglobinopathies; Haemolytic anaemias; Hb E thalassaemia; Malaysia; Pregnancy
Study site: Hospital Orang Asli, Gombak, Selangor, Malaysia
Fulltext Gender differences and psychological factors associated with suicidal ideation among youth in Malaysia

Ibrahim N, Amit N, Che Din N, Ong HC

Psychol Res Behav Manag, 2017;10:129-135.
PMID: 28496374 DOI: 10.2147/PRBM.S125176

Suicide is a global phenomenon that has been showing an upward trend in recent years. It is the second leading cause of death among youth. Studies on suicidal ideation warrant greater attention, as it leads to suicide attempts and other health risk behaviors. Thus, the objective of this study was to compare gender differences in suicidal ideation and determine the predictors of suicidal ideation among youth. This cross-sectional study was carried out among 232 youths aged between 15 and 25 years from selected urban areas in Malaysia. The results showed that suicidal ideation was higher among male participants compared with female participants. Age was the predictor of suicidal ideation for males, while depression and loss of motivation, as components of hopelessness, were the predictors of suicidal ideation among females. Hence, it is important that professionals conduct early identification tests for suicidality among young people. This will facilitate the early detection of depression and hopelessness, which is important, in order to prevent suicidal behaviors or other problems before these occur.
Fourth generation biofuel from genetically modified algal biomass: Challenges and future directions

Shokravi H, Shokravi Z, Heidarrezaei M, Ong HC, Rahimian Koloor SS, Petrů M, et al.

Chemosphere, 2021 Dec;285:131535.
PMID: 34329137 DOI: 10.1016/j.chemosphere.2021.131535

Genetic engineering applications in the field of biofuel are rapidly expanding due to their potential to boost biomass productivity while lowering its cost and enhancing its quality. Recently, fourth-generation biofuel (FGB), which is biofuel obtained from genetically modified (GM) algae biomass, has gained considerable attention from academic and industrial communities. However, replacing fossil resources with FGB is still beset with many challenges. Most notably, technical aspects of genetic modification operations need to be more fully articulated and elaborated. However, relatively little attention has been paid to GM algal biomass. There is a limited number of reviews on the progress and challenges faced in the algal genetics of FGB. Therefore, the present review aims to fill this gap in the literature by recapitulating the findings of recent studies and achievements on safe and efficient genetic manipulation in the production of FGB. Then, the essential issues and parameters related to genome editing in algal strains are highlighted. Finally, the main challenges to FGB pertaining to the diffusion risk and regulatory frameworks are addressed. This review concluded that the technical and biosafety aspects of FGB, as well as the complexity and diversity of the related regulations, legitimacy concerns, and health and environmental risks, are among the most important challenges that require a strong commitment at the national/international levels to reach a global consensus.

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