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Dynamic assessment of parathyroid function in acute malaria

Davis TM, Singh B, Choo KE, Ibrahim J, Sulaiman SA, Kadir ZA, et al.

J Intern Med, 1998 May;243(5):349-54.
PMID: 9651556

OBJECTIVES: To investigate the dynamic parathyroid response to rapidly induced, sustained hypocalcaemia in patients with acute malaria and in healthy volunteers.
DESIGN: Serum intact parathormone (PTH) concentrations were measured on samples taken before and during a variable-rate tri-sodium citrate infusion designed to 'clamp' the whole blood ionised calcium concentration 0.20 mmol L-1 below baseline for 120 min.
SUBJECTS: Six Malaysian patients aged 17-42 years with acute malaria, four of whom were restudied in convalescence, and 12 healthy controls aged 19-36 years.
MAIN OUTCOME MEASURES: Whole-blood ionised calcium and serum intact PTH concentrations.
RESULTS: The mean (SD baseline ionised calcium was lower in the malaria patients than in controls (1.09 +/- 0.06 vs. 1.18 +/- 0.03 mmol L-1, respectively; P = 0.01) but PTH concentrations were similar (3.0 +/- 1.8 vs. 3.3 +/- 1.3 pmol L(-1); P = 0.33). Target whole-blood ionised calcium concentrations were achieved more rapidly in the controls than the patients (within 15 vs. 30 min) despite significantly more citrate being required in the patients (area under the citrate infusion-time curve 0.95 (0.25 vs. 0.57 +/- 0.09 mmol kg-1; P < 0.01). The ratio of the change in serum PTH to that in ionised calcium (delta PTH/ delta Ca2+), calculated to adjust for differences in initial rate of fall of ionised calcium, was similar during the first 5 min of the clamp (132 +/- 75 x 10(-6) vs. 131 +/- 43 x 10(-6) in patients and controls, respectively, P > 0.05), as were steady-state serum PTH levels during the second hour (7.0 +/- 2.2 pmol L-1 in each case). Convalescent patients had normal basal ionised calcium levels but the lowest serum intact PTH levels before and during the clamp, consistent with an increase in skeletal PTH sensitivity after treatment.
CONCLUSIONS: There is a decreased ionised calcium 'set point' for basal PTH secretion but a normal PTH response to acute hypocalcaemia in malaria. Skeletal resistance may attenuate the effects of the PTH response but patients with malaria appear relatively resistant to the calcium chelating effects of citrated blood products.
Fulltext Guideline adherence and control of diabetes mellitus with co-morbidities in a tertiary-care hospital in Malaysia [Abstract]

Iqbal MZ, Iqbal MS, Khan AH, Sulaiman SA, Iqbal MW

Value Health, 2014 Nov;17(7):A353.
PMID: 27200693 DOI: 10.1016/j.jval.2014.08.744

Conference abstract:
OBJECTIVES.. To evaluate doctors’ adherence to Malaysian Clinical Practice Guideline (CPG) 2009 in the management of diabetes mellitus with co-morbidities in Malaysia.
METHODS. Cross-sectional study was done at a tertiary-care hospital in Malaysia. Total 51 physicians and 1020 patients’ prescriptions written by same physicians (20 prescriptions per physician) were analyzed. All patients had diabetes mellitus with co-morbidities. Depending on the recommendations of CPG 2009, the prescriptions were clustered as adherent and non-adherent prescriptions. All obtained data were analyzed using descriptive and inferential statistics.
RESULTS. A statistically significant negative association (Ф= 0.094, p-value=0.003) was observed between diabetes mellitus control and co-morbidities. CPG adherent had statistically weak negative association (Ф= - 0.081, p-value=0.010) with patients having co-morbidities (41.6%). No statistically significant association was observed between CPG adherence and any other co-morbidity. Majority of the patients received guidelines-compliant pharmacotherapy. The overall good level of physician adherence with CPG 2009 was observed in the management of diabetes mellitus with co-morbidities.
CONCLUSIONS. The study explored several features of prescription pattern of the physicians involved in the management of diabetes mellitus with co-morbidities and recognized the need for improvement in their prescription pattern for treating the diabetes mellitus.
The role of some cyclorrhaphan flies as carriers of human helminths in Malaysia

Sulaiman S, Sohadi AR, Yunus H, Iberahim R

Med Vet Entomol, 1988 Jan;2(1):1-6.
PMID: 2980156

The role of some adult flies (Diptera: Cyclorrhapha) as carriers of helminth parasites of man was studied at four sites in Malaysia: a refuse dump, where no helminth-positive flies were detected, and in three peri-domestic situations where four species of flies carried up to three types of nematodes. The dominant fly species Chrysomya megacephala (Fabricius) carried eggs of the roundworm Ascaris lumbricoides L., the pinworm Trichuris trichiura (L.) and hookworm on the adult external body surface and in the gut lumen, in association with Bukit Lanjan aborigines. Chrysomya rufifacies (Macquart) and Sarcophaga spp. also had Ascaris lumbricoides and Trichurus trichiura eggs in their gut contents. Human helminths were not recovered from Lispe leucospila (Wiedemann), Lucilia cuprina (Wiedemann) or the housefly Musca domestica L. In an urban slum area of Kuala Lumpur city, filariform larvae identified as the hookworm Necator americanus (Stiles) occurred in the intestines of the face-fly Musca sorbens Wiedemann (22 larvae per 100 flies) and of Chrysomya megacephala (4.5 larvae per 100 flies). This concentration of apparently infective N. americanus in M. sorbens, a fly which often breeds in faeces and browses on human skin, could have transmission potential.
Dietary carbohydrate, fiber and sugar and risk of breast cancer according to menopausal status in Malaysia

Sulaiman S, Shahril MR, Wafa SW, Shaharudin SH, Hussin SN

Asian Pac J Cancer Prev, 2014;15(14):5959-64.
PMID: 25081729

BACKGROUND: Dietary carbohydrate, fiber and sugar intake has been shown to play a role in the etiology of breast cancer, but the findings have been inconsistent and limited to developed countries with higher cancer incidence.
OBJECTIVE: To examine the association of premenopausal and postmenopausal breast cancer risk with dietary carbohydrate, fiber and sugar intake.
MATERIALS AND METHODS: This population based case-control study was conducted in Malaysia with 382 breast cancer patients and 382 controls. Food intake pattern was assessed via an interviewer-administered food frequency questionnaire. Logistic regression was used to compute odds ratios (OR) with 95% confidence intervals (CI) and a broad range of potential confounders were included in analysis.
RESULTS: A significant two fold increased risk of breast cancer among premenopausal (OR Q4 to Q1=1.93, 95%CI: 1.53-2.61, p-trend=0.001) and postmenopausal (OR Q4 to Q1=1.87, 95%CI: 1.03-2.61, p-trend=0.045) women was observed in the highest quartile of sugar. A higher intake of dietary fiber was associated with a significantly lower breast cancer risk among both premenopausal (OR Q4 to Q1=0.31, 95%CI: 0.12-0.79, p-trend=0.009) and postmenopausal (OR Q4 to Q1=0.23, 95%CI: 0.07-0.76, p-trend=0.031) women.
CONCLUSIONS: Sugar and dietary fiber intake were independently related to pre- and postmenopausal breast cancer risk. However, no association was observed for dietary carbohydrate intake.
Fulltext The use of complementary and alternative medicine among Malay breast cancer survivors

Shaharudin SH, Sulaiman S, Emran NA, Shahril MR, Hussain SN

Altern Ther Health Med, 2011 Jan-Feb;17(1):50-6.
PMID: 21614944

BACKGROUND: A cross-sectional study was carried out to determine the prevalence of complementary and alternative medicine (CAM) use by breast cancer survivors.
METHODS: A descriptive survey design was developed. Information on socio-demographic characteristics, cancer clinical treatment history, and use of CAM were obtained through a modified self-administered questionnaire from 116 Malay breast cancer survivors aged 21 to 67 years who were 2 years postdiagnosis and currently undergoing follow-up treatment at breast cancer clinics at Hospital Kuala Lumpur and Universiti Kebangsaan Malaysia Medical Centre.
RESULTS: Data suggest that 64% of the participants were identified as CAM users; dietary supplements were the most common form used, followed by prayer and Malay traditional medicine. Within the wide range of dietary supplements, multivitamins were most often taken followed by spirulina, vitamin C, evening primrose oil, and herbal products. Contrary to other findings, the CAM users were found to be older, had secondary education levels, and were from middle-income households. However, there was no significant difference between CAM users and nonusers in this study. Family members played an important role as the main source of information along with doctors/health care providers, friends, and printed materials/mass media. The reasons participants gave for using CAM were mainly to assist in healing the body's inner strength, to cure cancer, and to reduce stress. Only half of the participants consulted with their physicians regarding the safety of CAM use. The participants began to use CAM while undergoing clinical treatments. Most of the participants used CAM for more than a year. About RM100 to RM149 (31.88 USD to 47.50 USD at press time) were spent monthly on CAM by 32% of the participants. The CAM use was found to be effective and beneficial for patients' disease states, and they were contented with the usage of the CAM therapies. Multivariate analysis revealed that thedecision to use or not to use CAM was not dependent on sociodemographic background or cancer clinical treatment history.
CONCLUSIONS: CAM was commonly used by breast cancer survivors as a coping mechanism to battle the disease.
Study site: Breast cancer clinics, Hospital Kuala Lumpur and Pusat Perubatan Universiti Kebangsaan Malaysia (PPUKM), Kuala Lumpur, Malaysia
Fat intake and its relationship with pre- and post-menopausal breast cancer risk: a case-control study in Malaysia

Sulaiman S, Shahril MR, Shaharudin SH, Emran NA, Muhammad R, Ismail F, et al.

Asian Pac J Cancer Prev, 2011;12(9):2167-78.
PMID: 22296351

BACKGROUND: Fat intake has been shown to play a role in the etiology of breast cancer, but the findings have been inconsistent.
OBJECTIVE: To assess the association of premenopausal and postmenopausal breast cancer risk with fat and fat subtypes intake.
METHODOLOGY: This is a population based case-control study conducted in Kuala Lumpur, Malaysia from January 2006 to December 2007. Food intake pattern was collected from 382 breast cancer patients and 382 control group via an interviewer-administered food frequency questionnaire. Logistic regression was used to compute odds ratios (OR) with 95% confidence intervals (CI) and a broad range of potential confounders was included in analysis.
RESULTS: This study showed that both premenopausal and postmenopausal breast cancer risk did not increase significantly with greater intake of total fat [quartile (Q) 4 versus Q1 OR=0.76, 95% CI, 0.23-2.45 and OR=1.36, 95% CI, 0.30-3.12], saturated fat (ORQ4 to Q1=1.43, 95% CI, 0.51-3.98 and ORQ4 to Q1=1.75, 95% CI, 0.62-3.40), monounsaturated fat (ORQ4 to Q1=0.96, 95% CI, 0.34-1.72 and ORQ4 to Q1=1.74, 95% CI, 0.22-2.79), polyunsaturated fat (ORQ4 to Q1=0.64, 95% CI, 0.23-1.73 and ORQ4 to Q1=0.74, 95% CI, 0.39-1.81), n-3 polyunsaturated fat (ORQ4 to Q1=1.10, 95% CI, 0.49-2.48 and ORQ4 to Q1=0.78, 95% CI, 0.28-2.18), n-6 polyunsaturated fat (ORQ4 to Q1=0.67, 95% CI, 0.24-1.84 and ORQ4 to Q1=0.71, 95% CI, 0.29-1.04) or energy intake (ORQ4 to Q1=1.52, 95% CI, 0.68-3.38 and ORQ4 to Q1=2.21, 95% CI, 0.93-3.36).
CONCLUSION: Total fat and fat subtypes were not associated with pre- and postmenopausal breast cancer risk after controlling for age, other breast cancer risk factors and energy intake. Despite the lack of association, the effects of total fat and fat subtypes intake during premenopausal years towards postmenopausal breast cancer risk still warrant investigation.
Association of nutritional status with quality of life in breast cancer survivors

Mohammadi S, Sulaiman S, Koon PB, Amani R, Hosseini SM

Asian Pac J Cancer Prev, 2013;14(12):7749-55.
PMID: 24460363

Nutritional status and dietary intake play a significant role in the prognosis of breast cancer and may modify the progression of disease. The aim of this study was to determine the influence of nutritional status on the quality of life of Iranian breast cancer survivors. Cross-sectional data were collected for 100 Iranian breast cancer survivors, aged 32 to 61 years, attending the oncology outpatient clinic at Golestan Hospital, Ahvaz, Iran. Nutritional status of subjects was assessed by anthropometric measurements, Patient-Generated Subjective Global Assessment (PG-SGA) and three non-consecutive 24-hour diet recalls. The European Organization of Research and Treatment of Cancer Quality of Life form (EORTC QLQ-C30) was used to assess quality of life. Ninety-four percent of the survivors were well-nourished, 6% were moderately malnourished or suspected of being malnourished while none were severely malnourished. Prevalence of overweight and obesity was 86%. Overall, participants had an inadequate intake of vitamin D, E, iron and magnesium according to dietary reference intake (DRI) recommendations. Survivors with better nutritional status had better functioning scales and experienced fewer clinical symptoms. It appears important to provide educational and nutritional screening programs to improve cancer survivor quality of life.
Impact of healthy eating practices and physical activity on quality of life among breast cancer survivors

Mohammadi S, Sulaiman S, Koon PB, Amani R, Hosseini SM

Asian Pac J Cancer Prev, 2013;14(1):481-7.
PMID: 23534778

Following breast cancer diagnosis, women often attempt to modify their lifestyles to improve their health and prevent recurrence. These behavioral changes typically involve diet and physical activity modification. The aim of this study was to determine association between healthy eating habits and physical activity with quality of life among Iranian breast cancer survivors. A total of 100 Iranian women, aged between 32 to 61 years were recruited to participate in this cross-sectional study. Eating practices were evaluated by a validated questionnaire modified from the Women's Healthy Eating and Living (WHEL) study. Physical activity was assessed using the International Physical Activity Questionnaire (IPAQ). A standardized questionnaire by the European Organization of Research and Treatment of Cancer Quality of Life and its breast cancer module (EORTC QLQ-C30/+BR-23) were applied to determine quality of life. Approximately 29% of the cancer survivors were categorized as having healthy eating practices, 34% had moderate eating practices and 37% had poor eating practices based on nutrition guidelines. The study found positive changes in the decreased intake of fast foods (90%), red meat (70%) and increased intake of fruits (85%) and vegetables (78%). Generally, breast cancer survivors with healthy eating practices had better global quality of life, social, emotional, cognitive and role functions. Result showed that only 12 women (12%) met the criteria for regular vigorous exercise, 22% had regular moderate-intensity exercise while the majority (65%) had low-intensity physical activity. Breast cancer survivors with higher level of physical activity had better emotional and cognitive functions. Healthy eating practices and physical activity can improve quality of life of cancer survivors. Health care professionals should promote good dietary habits and physical activity to improve survivors' health and quality of life.
Fulltext Microstructural, Tribology and Corrosion Properties of Optimized Fe3O4-SiC Reinforced Aluminum Matrix Hybrid Nano Filler Composite Fabricated through Powder Metallurgy Method

Ashrafi N, Azmah Hanim MA, Sarraf M, Sulaiman S, Hong TS

Materials (Basel), 2020 Sep 15;13(18).
PMID: 32942621 DOI: 10.3390/ma13184090

Hybrid reinforcement's novel composite (Al-Fe3O4-SiC) via powder metallurgy method was successfully fabricated. In this study, the aim was to define the influence of SiC-Fe3O4 nanoparticles on microstructure, mechanical, tribology, and corrosion properties of the composite. Various researchers confirmed that aluminum matrix composite (AMC) is an excellent multifunctional lightweight material with remarkable properties. However, to improve the wear resistance in high-performance tribological application, hardening and developing corrosion resistance was needed; thus, an optimized hybrid reinforcement of particulates (SiC-Fe3O4) into an aluminum matrix was explored. Based on obtained results, the density and hardness were 2.69 g/cm3, 91 HV for Al-30Fe3O4-20SiC, after the sintering process. Coefficient of friction (COF) was decreased after adding Fe3O4 and SiC hybrid composite in tribology behaviors, and the lowest COF was 0.412 for Al-30Fe3O4-20SiC. The corrosion protection efficiency increased from 88.07%, 90.91%, and 99.83% for Al-30Fe3O4, Al-15Fe3O4-30SiC, and Al-30Fe3O4-20SiC samples, respectively. Hence, the addition of this reinforcement (Al-Fe3O4-SiC) to the composite shows a positive outcome toward corrosion resistance (lower corrosion rate), in order to increase the durability and life span of material during operation. The accomplished results indicated that, by increasing the weight percentage of SiC-Fe3O4, it had improved the mechanical properties, tribology, and corrosion resistance in aluminum matrix. After comparing all samples, we then selected Al-30Fe3O4-20SiC as an optimized composite.
Fulltext Determination of mineral, parathyroid hormone, and 6-keto-prostaglandin-F1 alpha levels in pregnant women with hypertension and pre-eclampsia

Sulaiman S, Adeeb N, Muslim N, Adeeb N, Ho CM

Singapore Med J, 1995 Dec;36(6):637-40.
PMID: 8781637

Determinations of total calcium, total magnesium, calcium ion, parathyroid hormone and 6-keto-prostaglandin-F1 alpha levels were carried out on 84 blood samples from 4 groups of women categorised as non-pregnant normotensive (NNP), pregnant normotensive (NP), pregnancy-induced hypertension (PIH) and pre-eclampsia (PE). PIH was clinically diagnosed when the diastolic pressure was more than 90 mmHg and was only hypertensive during pregnancy while PE was with additional proteinuria after 20 weeks of gestation. Compared to NNP women, total calcium and parathyroid hormone levels were of lower levels (p < 0.05) in NP women while in PIH women, total calcium and 6-keto-prostaglandin-F1 alpha levels were also lowered (p < 0.05). Compared to NNP women, PE women's levels of total calcium, calcium ion and 6-keto-prostaglandin-F1 alpha decreased (p < 0.05) while parathyroid hormone level increased (p < 0.05). When compared to the NP women, PE women had decreased levels (p < 0.05) of total calcium as well as calcium ion and increased level (p < 0.05) of parathyroid hormone. Calcium ion was found to be negatively correlated (NNP : r = -0.883, p = 0.008/NP : r = -0.931, p = 0.000) while parathyroid hormone was positively correlated (NNP : r = 0.904, p = 0.013/NP : r = 0.913, p = 0.000) with mean arterial pressure.
Fulltext Residual effects of TMOF-Bti formulations against 1(st) instar Aedes aegypti Linnaeus larvae outside laboratory

Saiful AN, Lau MS, Sulaiman S, Hidayatulfathi O

Asian Pac J Trop Biomed, 2012 Apr;2(4):315-9.
PMID: 23569922 DOI: 10.1016/S2221-1691(12)60031-8

To evaluate the effectiveness and residual effects of trypsin modulating oostatic factor-Bacillus thuringiensis israeliensis (TMOF-Bti) formulations against Aedes aegypti (Ae. aegypti) (L.) larvae at UKM Campus Kuala Lumpur.
Date fruit consumption at term: Effect on length of gestation, labour and delivery

Razali N, Mohd Nahwari SH, Sulaiman S, Hassan J

J Obstet Gynaecol, 2017 Jul;37(5):595-600.
PMID: 28286995 DOI: 10.1080/01443615.2017.1283304

Labour induction and augmentation with Prostaglandin and Oxytocin are well established as standard practice worldwide. They are safe when used judiciously, but may be associated with maternal and neonatal morbidities. Other safer alternatives have been studied including dates consumption during late pregnancy with various outcomes. The aim of this randomised controlled trial was to investigate the effect of date fruit consumption during late pregnancy on the onset of labour and need for induction or augmentation of labour. A total of 154 nulliparous women with an uncomplicated singleton pregnancy were randomly allocated to either dates-consumer (77) or control group (77). The women in the dates-consumer group had significantly less need for augmentation of labour and longer intervention to delivery interval. There was no significant difference in the onset of spontaneous labour. Dates consumption reduces the need for labour augmentation but does not expedite the onset of labour. Impact statement • Dates fruit consumption during late pregnancy has been shown to positively affect the outcome of labour and delivery. In this study, date consumption reduced the need for labour augmentation with oxytocin but did not expedite the onset of labour. Therefore, dates consumption in late pregnancy is a safe supplement to be considered as it reduced the need for labour intervention without any adverse effect on the mother and child. This further supports the finding of earlier studies.
Fulltext Hypertension Treatment in Chronic Kidney Disease Stage 3, 4 and 5: A Hospital Based Cross-Sectional Study in Malaysia

Adnan AS, Salman M, Sulaiman SA, Khan AH, Hamzah DA

Value Health, 2014 Nov;17(7):A757.
PMID: 27202763 DOI: 10.1016/j.jval.2014.08.237
Antioxidant protection of Malaysian tualang honey in pancreas of normal and streptozotocin-induced diabetic rats

Erejuwa OO, Sulaiman SA, Wahab MS, Sirajudeen KN, Salleh MS, Gurtu S

Ann Endocrinol (Paris), 2010 Sep;71(4):291-6.
PMID: 20398890 DOI: 10.1016/j.ando.2010.03.003

Glucotoxicity contributes to beta-cell dysfunction through oxidative stress. Our previous study demonstrated that tualang honey ameliorated renal oxidative stress and produced hypoglycemic effect in streptozotocin (STZ)-induced diabetic rats. This present study investigated the hypothesis that hypoglycemic effect of tualang honey might partly be due to protection of pancreas against oxidative stress. Diabetes was induced by a single dose of STZ (60 mg/kg; ip). Diabetic rats were randomly divided into two groups and administered distilled water (0.5 ml/d) and tualang honey (1.0 g/kg/d). Similarly, two groups of non-diabetic rats received distilled water (0.5 ml/d) and tualang honey (1.0 g/kg/d). The animals were treated orally for 28 days. At the end of the treatment period, the honey-treated diabetic rats had significantly (p<0.05) reduced blood glucose levels [8.8 (5.8)mmol/L; median (interquartile range)] compared with the diabetic control rats [17.9 (2.6)mmol/L]. The pancreas of diabetic control rats showed significantly increased levels of malondialdehyde (MDA) and up-regulation of superoxide dismutase (SOD) and glutathione peroxidase (GPx) activities. Catalase (CAT) activity was significantly reduced while glutathione-S-transferase (GST) and glutathione reductase (GR) activities remained unchanged in the pancreas of diabetic rats. Tualang honey significantly (p<0.05) reduced elevated MDA levels. Honey treatment also restored SOD and CAT activities. These results suggest that hypoglycemic effect of tualang honey might be attributed to its antioxidative effect on the pancreas.
Assessment of dispersive liquid-liquid microextraction conditions for gas chromatography time-of-flight mass spectrometry identification of organic compounds in honey

Moniruzzaman M, Rodríguez I, Rodríguez-Cabo T, Cela R, Sulaiman SA, Gan SH

J Chromatogr A, 2014 Nov 14;1368:26-36.
PMID: 25441341 DOI: 10.1016/j.chroma.2014.09.057

The suitability of the dispersive liquid-liquid microextraction (DLLME) technique for gas chromatography (GC) characterization of minor organic compounds in honey samples is evaluated. Under optimized conditions, samples were pre-treated by liquid-liquid extraction with acetonitrile followed by DLLME using carbon tetrachloride (CCl4, 0.075 mL) as extractant. The yielded settled phase was analyzed by GC using high resolution time-of-flight (TOF) mass spectrometry (MS). The whole sample preparation process is completed in approximately 10 min, with a total consumption of organic solvents below 4 mL, relative standard deviations lower than 12% and with more than 70 organic compounds, displaying linear retention index in the range from 990 to 2900, identified in the obtained extracts. In comparison with HS SPME extraction, higher peak intensities were attained for most volatile and semi-volatile compounds amenable to both extraction techniques. Furthermore, other species such as highly polar and water soluble benzene acids, long chain fatty acids, esters and flavonoids, which are difficult to concentrate by HS SPME, could be identified in DLLME extracts. Some of the compounds identified in DLLME extracts have been proposed as useful for samples classification and/or they are recognized as markers of honeys from certain geographic areas.
Assessment of gas chromatography time-of-flight accurate mass spectrometry for identification of volatile and semi-volatile compounds in honey

Moniruzzaman M, Rodríguez I, Ramil M, Cela R, Sulaiman SA, Gan SH

Talanta, 2014 Nov;129:505-15.
PMID: 25127626 DOI: 10.1016/j.talanta.2014.06.019

The performance of gas chromatography (GC) combined with a hybrid quadrupole time-of-flight (QTOF) mass spectrometry (MS) system for the determination of volatile and semi-volatile compounds in honey samples is evaluated. After headspace (HS) solid-phase microextraction (SPME) of samples, the accurate mass capabilities of the above system were evaluated for compounds identification. Accurate scan electron impact (EI) MS spectra allowed discriminating compounds displaying the same nominal masses, but having different empirical formulae. Moreover, the use of a mass window with a width of 0.005 Da provided highly specific chromatograms for selected ions, avoiding the contribution of interferences to their peak areas. Additional information derived from positive chemical ionization (PCI) MS spectra and ion product scan MS/MS spectra permitted confirming the identity of novel compounds. The above possibilities are illustrated with examples of honey aroma compounds, belonging to different chemical classes and containing different elements in their molecules. Examples of compounds whose structures could not be described are also provided. Overall, 84 compounds, from a total of 89 species, could be identified in 19 honey samples from 3 different geographic areas in the world. The suitability of responses measured for selected ions, corresponding to above species, for authentication purposes is assessed through principal components analysis.
Phenolic acid composition and antioxidant properties of Malaysian honeys

Khalil MI, Alam N, Moniruzzaman M, Sulaiman SA, Gan SH

J Food Sci, 2011 Aug;76(6):C921-8.
PMID: 22417491 DOI: 10.1111/j.1750-3841.2011.02282.x

The phenolic acid and flavonoid contents of Malaysian Tualang, Gelam, and Borneo tropical honeys were compared to those of Manuka honey. Ferric reducing/antioxidant power assay (FRAP) and the 1,1-diphenyl-2-picryl-hydrazyl (DPPH) radical-scavenging activities were also quantified. All honey extracts exhibited high phenolic contents (15.21 ± 0.51- 42.23 ± 0.64 mg/kg), flavonoid contents (11.52 ± 0.27- 25.31 ± 0.37 mg/kg), FRAP values (892.15 ± 4.97- 363.38 ± 10.57 μM Fe[II]/kg), and high IC₅₀ of DPPH radical-scavenging activities (5.24 ± 0.40- 17.51 ± 0.51 mg/mL). Total of 6 phenolic acids (gallic, syringic, benzoic, trans-cinnamic, p-coumaric, and caffeic acids) and 5 flavonoids (catechin, kaempferol, naringenin, luteolin, and apigenin) were identified. Among the Malaysian honey samples, Tualang honey had the highest contents of phenolics, and flavonoids, and DPPH radical-scavenging activities. We conclude that among Malaysian honey samples, Tualang honey is the richest in phenolic acids, and flavonoid compounds, which have strong free radical-scavenging activities.
Advances in the analytical methods for determining the antioxidant properties of honey: a review

Moniruzzaman M, Khalil MI, Sulaiman SA, Gan SH

Afr J Tradit Complement Altern Med, 2012;9(1):36-42.
PMID: 23983317

Free radicals and reactive oxygen species (ROS) have been implicated in contributing to the processes of aging and disease. In an effort to combat free radical activity, scientists are studying the effects of increasing individuals' antioxidant levels through diet and dietary supplements. Honey appears to act as an antioxidant in more ways than one. In the body, honey can mop up free radicals and contribute to better health. Various antioxidant activity methods have been used to measure and compare the antioxidant activity of honey. In recent years, DPPH (Diphenyl-1-picrylhydrazyl), FRAP (Ferric Reducing Antioxidant Power), ORAC (The Oxygen Radical Absorbance Capacity), ABTS [2, 2-azinobis (3ehtylbenzothiazoline-6-sulfonic acid) diamonium salt], TEAC [6-hydroxy-2, 5, 7, 8-tetramethylchroman-2-carboxylic acid (Trolox)-equivalent antioxidant capacity] assays have been used to evaluate antioxidant activity of honey. The antioxidant activity of honey is also measured by ascorbic acid content and different enzyme assays like Catalase (CAT), Glutathione Peroxidase (GPO), Superoxide Dismutase (SOD). Among the different methods available, methods that have been validated, standardized and widely reported are recommended.
Quantitative determination of propranolol by ultraviolet HPLC in human plasma

Salman SA, Sulaiman SA, Ismail Z, Gan SH

Toxicol. Mech. Methods, 2010 Mar;20(3):137-42.
PMID: 20128736 DOI: 10.3109/15376511003602112

Many previous published methods for the quantitative determination of propranolol (PRN) in human plasma have poor recoveries and were not validated according to the FDA guideline. The aim of this study is to develop a simple HPLC method for detecting PRN in human plasma and to validate it so that it can be applied to a clinical study. Chromatographic separation was achieved using a mixture of a mobile phase consisting of 160 ml water, 180 ml methanol, 70 ml acetonitrile, 2.5 ml acetic acid, and 125 microl triethylamine (v/v). The pH of the whole mixture was adjusted to 3.4. A flow rate of 0.5 ml/min was employed throughout with a 15 microl injection volume. Detection was done using a UV detector at 291 nm. The validated method was linear for concentrations ranging from 15-180 ng/ ml with a good separation and specificity for both PRN and its internal standard, oxprenolol (OXP), with excellent recoveries, precision, and accuracies. The limit of detection (LOD) and limit of quantification (LOQ) were 1 and 10 ng/ml, respectively. The stability studies demonstrated that PRN is stable in the autosampler vials and also up to 3.5 months. To the authors' knowledge, the recovery, that ranged between 97.9-102.7%, is the highest among all previously reported methods that used HPLC with UV detection. The developed and validated method for PRN analysis is excellent and applicable to a clinical study.
High 5-hydroxymethylfurfural concentrations are found in Malaysian honey samples stored for more than one year

Khalil MI, Sulaiman SA, Gan SH

Food Chem Toxicol, 2010 Aug-Sep;48(8-9):2388-92.
PMID: 20595027 DOI: 10.1016/j.fct.2010.05.076

5-Hydroxymethylfurfural (HMF) content is an indicator of the purity of honey. High concentrations of HMF in honey indicate overheating, poor storage conditions and old honey. This study investigated the HMF content of nine Malaysian honey samples, as well as the correlation of HMF formation with physicochemical properties of honey. Based on the recommendation by the International Honey Commission, three methods for the determination of HMF were used: (1) high performance liquid chromatography (HPLC), (2) White spectrophotometry and (3) Winkler spectrophotometry methods. HPLC and White spectrophotometric results yielded almost similar values, whereas the Winkler method showed higher readings. The physicochemical properties of honey (pH, free acids, lactones and total acids) showed significant correlation with HMF content and may provide parameters that could be used to make quick assessments of honey quality. The HMF content of fresh Malaysian honey samples stored for 3-6 months (at 2.80-24.87 mg/kg) was within the internationally recommended value (80 mg/kg for tropical honeys), while honey samples stored for longer periods (12-24 months) contained much higher HMF concentrations (128.19-1131.76 mg/kg). Therefore, it is recommended that honey should generally be consumed within one year, regardless of the type.

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