1.Antimicrobial effect of Malaysian green tea leaves (Camellia sinensis) on the skin microbiota
Hassanain Al-Talib ; Noor Alicezah Mohd Kasim ; Alyaa Al-Khateeb ; Chandrika Murugaiah ; Azrul Abdul Aziz ; Niena Nazleen Rashid ; Nazihah Azizan ; Shairah Ridzuan
Malaysian Journal of Microbiology 2016;12(6):423-427
Aims:
Camellia sinensis
(
green t
ea) is known for its therapeutic properties (anti
-
inflammatory, anti
-
oxidative and anti
-
ageing). The aim of this study was to determine the
in vitro
inhibitory activity of gree
n tea extract on some odorous skin
commensal bacteria.
Methodology and results:
Tea leaves were collected from
MARDI Agro Technology Park, Cameron Highlands. A
standardised protocol was used to obtain green tea extract. Aqueous green tea extracts were tes
ted for antibacterial
activity by well diffusion method. Minimal inhibitory concentration (MIC) and minimal bactericidal concentration (MBC)
assays were performed by broth microdilution assays using green tea extract concen
trations from 16 to 0.0313 mg/
mL
.
Green tea
extract showed antibacterial activity against skin microbiota. The high antimicrobial effect was achieved
against
Micrococcus luteus
with MIC and MBC of 0.125 and 0.25 mg/μL respectively, followed by
Staphylococcus
epidermidis
with MIC and MBC o
f 0.25 and 0.25 mg/μL respectively,
Bacillus subtilis
with MIC and MBC of 0.5 and 0.5
mg/μL respectively and lastly,
Corynebacterium xerosis
with MIC and MBC of 0.5 and 1.0 mg/μL respectively.
Conclusion, significance and impact of study:
The results obta
ined from the study confirm the
in vitro
anti
-
microbial
activity of green tea extracts against skin microbiota. The antibacterial effects of green tea against skin bacteria with its
anti
-
oxidant and anti
-
aging properties will help in keeping skin healthy,
fresh and reducing unpleasant
odo
rs
.
Camellia sinensis
2. Antimicrobial effect of Malaysian vegetables against enteric bacteria
Hassanain AL-TALIB ; Norliana Dalila Mohamad ALI ; Mohamed Harreez SUHAIMI ; Siti Shafika Nabila ROSLI ; Nurul Huda OTHMAN ; Nur Ain Sakinah MANSOR ; Amira Kartini Sulaiman SHAH ; Nurul Syuhada ARIFFIN ; Alyaa AL-KHATEEB
Asian Pacific Journal of Tropical Biomedicine 2016;6(3):211-215
Objective: To investigate the antibacterial activities of green vegetables (pennywort, mint, garlic, parsley and celery) against four common enteric bacteria [Salmonella enterica (ATCC 25957) (S. enterica), Shigella flexneri (ATCC 12022) (S. flexneri), Escherichia coli (ATCC 43889) (E. coli) and Enterobacter cloacae (ATCC 13047) (E. cloacae)] as an alternative medicine for controlling food borne diarrhea disease and the synergistic effect of green vegetables against those bacteria. Methods: Five common vegetables (pennywort, mint, garlic, parsley and celery) were purchased and extracted. The antimicrobial activities of these extracts were tested against four common enteric bacteria (S. enterica, S. flexneri, E. coli and E. cloacae). Ten different concentrations of the extracts (from 640 to 1.25 mg/mL) were prepared and used for the study. The minimal inhibitory concentration (MIC) was determined by the broth dilution method. The antimicrobial activities were assessed by using both well diffusion and disc diffusion methods. Results: Garlic extract showed excellent inhibitory effects on all enteric bacteria. Other plants (parsley, celery, mint and pennywort) were not effective against enteric bacteria. The MIC of garlic against S. flexneri and E. cloacae was 40 mg/mL. The MIC of S. enterica and E. coli were 20 and 10 mg/mL, respectively. The performance of the well diffusion method was better than that of the disc diffusion method with clear and sharp inhibition zones of tested bacteria against plant extracts. Conclusions: Garlic had excellent antimicrobial effects against enteric bacteria and was recommended to be given to patients with gastroenteritis. The other vegetables (pennywort, mint, parsley and celery) showed no inhibitory effects on enteric bacteria but still can be used for its richness in vitamins and fibers. The performance of the well diffusion method was better than that of the disc diffusion method in detecting the antibacterial effects of green vegetables.
3.A quadriplex PCR assay for rapid detection of diarrhoeacausing parasitic protozoa from spiked stool samples
Al-Talib, H. ; Julia Ashazila, M.J. ; Hussaini, J. ; Wang, S.M. ; Mohd Shah, N.A. ; Al-Khateeb, A. ; Chandrika, M.
Tropical Biomedicine 2019;36(2):348-356
Diarrhoea is a leading killer of children, accounting for 9% of all deaths among
children under age 5 worldwide and 3% in Malaysia in 2015. A large proportion of diarrhoea
illnesses among children in developing countries are ascribed to an unknown etiology
because microscopic examination was the only available technique which has low detection
limits. The proposed study aimed to evaluate a new quadriplex PCR assay to detect
parasitic pathogens namely E. histolytica, G. lamblia and C. parvum which considered
responsible for the majority of human infections. Three set of specific primer pairs were
designed for detection of parasitic pathogens. Quadriplex PCR assay was optimized and an
internal amplification control was incorporated to check for PCR inhibitors in samples.
The PCR assay was evaluated using spiked stool samples. Specific primer pairs were
successfully designed and simultaneously amplified the targeted genes. The analytical
sensitivity of the quadriplex PCR at the DNA level was found to be 50 ng DNA. The
analytical specificity was evaluated with 11 reference protozoal and bacterial strains and
was found to be 100%. We concluded that the developed quadriplex PCR assay was rapid
and gave results within 5 hours which is essential for the identification of parasitic pathogen
and might be useful as an additional diagnostic tool whenever time is important in the
diagnosis of parasite that cause diarrhoea.