Synergistic Interaction of Methanol Extract from Canarium odontophyllum

Canarium odontophyllum (CO) Miq. has been considered as one of the most sought-after plant species in Sarawak, Malaysia, due to its nutritional and pharmacological benefits. This study aimed to evaluate the pharmacodynamic interaction of crude methanol and acetone extracts from CO leaves in combination with oxacillin, vancomycin, and linezolid, respectively, against MRSA ATCC 33591 as preliminary study has reported its potential antistaphylococcal activity. The broth microdilution assay revealed that both methanol and acetone extracts were bactericidal with Minimum Inhibitory Concentration (MIC) of 312.5 μg/mL and 156.25 μg/mL and Minimum Bactericidal Concentration (MBC) of 625 μg/mL and 312.5 μg/mL, respectively. Fractional Inhibitory Concentration (FIC) indices were obtained via the chequerboard dilution assay where methanol extract-oxacillin, acetone extract-oxacillin, methanol extract-linezolid, and acetone extract-linezolid combinations exhibited synergism (FIC index ≤ 0.5). The synergistic action of the methanol extract-oxacillin combination was verified by time-kill analysis where bactericidal effect was observed at concentration of 1/8 × MIC of both compounds at 9.6 h compared to oxacillin alone. As such, these findings postulated that both extracts exert their anti-MRSA mechanism of action similar to that of vancomycin and provide evidence that the leaves of C. odontophyllum have the potential to be developed into antistaphylococcal agents

In Vitro Antibacterial Activity of Galls of Quercus infectoria Olivier against Oral Pathogens

The galls of Quercus infectoria are commonly used in Malay traditional medicine to treat wound infections after childbirth. In India, they are employed traditionally as dental applications such as that in treatment of toothache and gingivitis. The aim of the present study was to evaluate the antibacterial activity of galls of Quercus infectoria Olivier against oral bacteria which are known to cause dental caries and periodontitis. Methanol and acetone extracts were screened against two Gram-positive bacteria (Streptococcus mutans ATCC 25175 and Streptococcus salivarius ATCC 13419) and two Gram-negative bacteria (Porphyromonas gingivalis ATCC 33277 and Fusobacterium nucleatum ATCC 25586). The screening test of antibacterial activity was performed using agar-well diffusion method. Subsequently, minimum inhibitory concentration (MIC) was determined by using twofold serial microdilution method at a concentration ranging between 0.01 mg/mL and 5 mg/mL. Minimum bactericidal concentration (MBC) was obtained by subculturing microtiter wells which showed no changes in colour of the indicator after incubation. Both extracts showed inhibition zones which did not differ significantly (P < 0.05) against each tested bacteria. Among all tested bacteria, S. salivarius was the most susceptible. The MIC ranges for methanol and acetone extracts were the same, between 0.16 and 0.63 mg/mL. The MBC value, for methanol and acetone extracts, was in the ranges 0.31–1.25 mg/mL and 0.31–2.50 mg/mL, respectively. Both extracts of Q. infectoria galls exhibited similar antibacterial activity against oral pathogens. Thus, the galls may be considered as effective phytotherapeutic agents for the prevention of oral pathogens

Potential Photochemopreventive Effect of Fatty Acids and Terpenoid Rich Leaf Extract of Canarium odontophyllum Miq. on UVB-induced Immortalized Human Keratinocytes (HaCaT) Skin Cancer Model.

Keratinocyte carcinoma is found in skin areas which are often exposed to the sun and a variety of natural products has been developed as a chemoprevention agent. One example is the Canarium odontophyllum Miq, or “Dabai”, which is an indigenous plant to Borneo, Sarawak. Fatty acids & terpenoid-rich extract from the leaf were obtained via extraction using hexane. FRAP assay showed antioxidant capacity for both 500 & 1000 µg/ml extract but not significantly different between doses. Untreated and treated immortalized human keratinocytes (HaCaT) were irradiated with UVB for 6 passages to a cumulative of 180 mJ/cm2 UVB. Findings showed 1000 ug/ml of TRCO significantly reduced p53 expression compared to the untreated group. Both 500 & 1000 µg/ml of TRCO significantly reduced the expression of Ki67 compared to the untreated group. Antioxidant and oxidative stress markers measurement revealed 500 µg/ml of TRCO significantly increased superoxide dismutase activity compared to the untreated group, both 500 & 1000 µg/ml TRCO significantly reduced catalase, glutathione peroxidase, glutathione S-transferase, and protein carbonyls compared to the untreated group. Reduced glutathione peroxidase activity is potentially due to depletion in glutathione by the UVB and extract. In vitro evaluations of TRCO on UVB-induced HaCaT skin cancer model revealed photochemopreventive properties. These promising findings validate further evaluation of C. odontophyllum Miq leaf extract as a potential therapeutic agent

GC-MS ANALYSIS OF TERPENOIDS FROM LEAVES OF Canarium odontophyllum Miq.(DABAI)

Terpenoids are defined as secondary metabolites with carbon backbone molecular structures consisting of isoprene (2-methylbuta-1, 3-diene) units. They demonstrate important biological activities, such as antibacterial, antiviral, antimalarial, antiinflammatory, anticancer and cholesterol synthesis inhibition activities. Canarium odontophyllum Miq. or locally known as “dabai” is an endemic plant in Sarawak, Malaysia. Its leaf compositions were examined by using the GC-MS analysis in order to compare and contrast their volatile terpenoids constituents. The terpenoids content were 36.67% and 14% for hexane and ethanol extracts, respectively. nHexadecanoic acid, phytol and octadecanoic acid were the major terpenoids constituents from the leaves of C. odontophyllum Miq. n-Hexadecanoic acid (20.22%), phytol (8.74%) and octadecanoic acid (7.54%) were found to be predominant in the hexane extract, while phytol(21.02%) and n-hexadecanoic acid (14.52%) were major constituents in the ethanol extract. The C.odontophyllum Miq. leaf constituents are also related to their biological activities and would offer promising therapeutic effects. Further investigation should be conducted to develop it as apotential therapeutic drug

UVB Induced Skin Cancer Development in Experimental Mouse Model : A Review

Skin cancer is a widespread global issue, with ultraviolet (UV) radiation being a significant risk factor. Researchers often use the mouse skin cancer model to develop novel therapeutic chemoprevention strategies. This model involves exposing mice to UVB radiation to induce skin arcinogenesis. In this short communication, we found that 69.57% of studies used female SKH-1 hairless mice, 17.39% used BALB/c mice, 8.69% used Swiss albino mice, and 4.35% used HRS/J hairless mice. All studies used mice aged 5-8 weeks. Different models of mice were exposed to varying doses of UVB radiation. SKH-1 hairless mice received UVB radiation twice a week for 10-18 weeks, while Swiss albino mice were exposed to UVB radiation three times a week for 30 weeks. HRS/J hairless mice received UVB radiation five times a week for 15 weeks. BALB/c mice were treated with DMBA and exposed to UVB radiation for 10-16 weeks to induce skin tumors. However, using SKH-1 hairless mice is costly. In conclusion, we can suggest BALB/c mice treated with DMBA and exposed to UVB radiation three times a week for 16 weeks for UVB-induced skin cancer model, as it is more cost-effective than other hairless mouse models

GC-MS ANALYSIS OF TERPENOIDS FROM LEAVES OF Canarium odontophyllum Miq.(DABAI)

Terpenoids are defined as secondary metabolites with carbon backbone molecular structures consisting of isoprene (2-methylbuta-1, 3-diene) units. They demonstrate important biological activities, such as antibacterial, antiviral, antimalarial, antiinflammatory, anticancer and cholesterol synthesis inhibition activities. Canarium odontophyllum Miq. or locally known as “dabai” is an endemic plant in Sarawak, Malaysia. Its leaf compositions were examined by using the GC-MS analysis in order to compare and contrast their volatile terpenoids constituents. The terpenoids content were 36.67% and 14% for hexane and ethanol extracts, respectively. nHexadecanoic acid, phytol and octadecanoic acid were the major terpenoids constituents from the leaves of C. odontophyllum Miq. n-Hexadecanoic acid (20.22%), phytol (8.74%) and octadecanoic acid (7.54%) were found to be predominant in the hexane extract, while phytol(21.02%) and n-hexadecanoic acid (14.52%) were major constituents in the ethanol extract. The C.odontophyllum Miq. leaf constituents are also related to their biological activities and would offer promising therapeutic effects. Further investigation should be conducted to develop it as apotential therapeutic drug

Fatty acids and terpenoids from Canarium odontophyllum MIQ. Leaf and their antioxidant and cytotoxic effects on UVB-induced immortalized human keratinocytes cells (HACAT)

The study evaluated the antioxidant capacity of hexane extract of Canarium odontophyllum Miq. leaf; its fatty acids and terpenoids content; and cytotoxic effects on UVB-induced human keratinocytes (HaCaT). FRAP assay was used to determine antioxidant capacity. GC-MS analysis to identify the fatty acids and terpenoids’ in the hexane extract of Canarium odontophyllum Miq. leaf. MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay was carried out to measure the cytotoxic effects of the extract on UVB-induced human keratinocytes. Serial doses of up to 1000 µg/mL extract were administered before UVB irradiation of the cells. FRAP assay showed the extract was found to exhibit antioxidant activity but no significant difference in ascorbic acid equivalent antioxidant capacity (AEAC) between dose 500 µg/mL (5.00 ± 0.35 AEAC) and 1000 µg/ mL (5.70 ± 0.29 AEAC) extract. GC-MS analysis showed the extract contained 88.93% of fatty acids and terpenoids, especially n-hexadecanoic acid, spathulenol, and phytol. MTT assay showed no IC50 value for the tested extract dose on UVB-induced HaCaT. Thus, the results suggest the potential application of hexane extract of C. odontophyllum Miq. leaf in terpenoids’ studies. In-depth research and isolation of compounds of interest should be done to develop it as a viable medical phytotherapeutic agent

Inhibitory and resistance-modifying potential of plant-based alkaloids against methicillin-resistant staphylococcus aureus (MRSA)

Increased prevalence of methicillin-resistant Staphylococcus aureus (MRSA) has become a major threat to the health sector worldwide due to their virulence, limited therapeutic options and their distribution in both hospital and community settings. Discovery and development of new anti-MRSA agents as alternatives to the very few antibiotics left in the armamentarium are, thus, urgently required. Recently, an efflux mechanism in MRSA has been identified as one of the main contributors of resistance towards various structurally unrelated antibiotics. The potential of reserpine (a phytoalkaloid) as efflux pump inhibitor (EPI) against various microbes remains limited as the concentration needed for inhibition is toxic to humans. This study therefore aimed to evaluate 13 alkaloid compounds as potential inhibitory agents and/or potential EPIs against a panel of three MRSA isolates which not only differ in their susceptibility to vancomycin (amongst the last drugs available to treat serious MRSA infection), but also exhibited active efflux activity. Results indicated berberine's moderate inhibitiory activity against two MRSA isolates scoring a minimum inhibitory concentration (MIC) value of 125 microg/ml. Notable efflux inhibitory activity (ranging from two- to eightfold Ethidium Bromide MIC reduction) meanwhile was detected from quinine, piperine and harmaline using reserpine as the positive control. Findings from this study support the opinion that a vast number of potential phytocompounds with pharmacological potential await discovery. Therapeutic application of these compounds, however, warrants further investigation to ascertain their pharmacodynamics and safety aspects

Chemopreventive Measurements and Oxidative Stress Effects of Terpenoid-rich Canarium odontophyllum Miq. Leaf Extract (TRCO) in Ultraviolet B-Induced In-Vitro Skin Carcinogenesis Model

The most common type of cancer found in the human outer and middle skin layers is keratinocyte carcinoma, often known as non-melanoma skin cancer. Although it can be aggressive, skin cancer is generally not fatal. This study aims to measure the chemopreventive and oxidative stress effects of terpenoid-rich Canarium odontophyllum Miq.’s leaf extract (TRCO) in the UVB-induced skin carcinogenesis model. The model involving human keratinocytes (HaCaT) was adapted with optimisations with pretreatment of 500 μg/ml TRCO (TRCO500) & 1000 μg/ml TRCO (TRCO1000). The HaCaT oncogenic transformation model’s repetitive UVB exposure resulted in altered cell shape, according to our findings. Pretreatment of TRCO1000 significantly reduced tumour protein p53 (TP53) and marker of proliferation KI-67 (KI67) expression in UVB-induced HaCaT. Treatment with TRCO resulted in an overall reduction in oxidative stress. TRCO pretreatment showed reduced lipid peroxides, LPO and significantly reduced protein carbonyls. In conclusion, the promising results of this chemopreventive study using TRCO on this in-vitro skin carcinogenesis model suggested that it is worthwhile to conduct further isolations and assessments of terpenoids from C. odontophyllum Miq. leaf as a possible chemoprevention agent

Prevalence and antibiotic resistance of Salmonella Enteritidis and Salmonella Typhimurium in raw chicken meat at retail markets in Malaysia

Salmonellosis is one of the major food-borne diseases in many countries. This study was carried out to determine the occurrence of Salmonella spp., Salmonella Enteritidis, and Salmonella Typhimurium in raw chicken meat from wet markets and hypermarkets in Selangor, as well as to determine the antibiotic susceptibility profile of S. Enteritidis and S. Typhimurium. The most probable number (MPN) in combination with multiplex polymerase chain reaction (mPCR) method was used to quantify the Salmonella spp., S. Enteritidis, and S. Typhimurium in the samples. The occurrence of Salmonella spp., S. Enteritidis, and S. Typhimurium in 120 chicken meat samples were 20.80%, 6.70%, and 2.50%, respectively with estimated quantity varying from <3 to 15 MPN/g. The antibiogram testing revealed differential multi-drug resistance among S. Enteritidis and S. Typhimurium isolates. All the isolates were resistance to erythromycin, penicillin, and vancomycin whereas sensitivity was recorded for Amoxicillin/Clavulanic acid, Gentamicin, Tetracycline, and Trimethoprim. Our findings demonstrated that the retail chicken meat could be a source of multiple antimicrobial-resistance Salmonella and may constitute a public health concern in Malaysia