ABSTRACT
The present study was carried out to evaluate the antibacterial and antioxidant potential of acetone and methanol extracts of lichen (Parmotrema praesorediosum, P. rampoddense, P. tinctorum and P. reticulatum) and isolated chemical constituents which are praesorediosic acid, protocetraric acid, usnic acid, α–collatolic acid, β-alectoronic acid, atranorin and chloroatranorin. The antibacterial activity was evaluated using broth dilution method. Acetone extracts (except for P. reticulatum) showed good inhibitory activity against S. aureus and B. subtilis with MIC values ranging from 500–125 µg/mL, whereas, no activity was observed for the methanol extracts. Extracts exhibited zero inhibitory activity against E. coli. The antioxidant ability was measured using a DPPH free radical scavenging activity assay. Only methanol extract of P. praesorediosum exhibited more than 50% scavenging activity. Among the isolates, usnic acid exhibited the strongest antibacterial activity against S. aureus and B. subtilis with MIC value 7.81 µg/mL. Praesorediosic acid and protocetraric acid isolates exclusively inhibited E. coli at concentration 125 µg/mL and displayed results exceeding 50% scavenging activity (57.57% and 63.97%, respectively). Hitherto, it is the first evaluation of antibacterial activity on lichens of Malaysian origin and to our knowledge; the first reported study on the biological activity of praesorediosic acid and Parmotrema rampoddense.
ABSTRACT
Objective To summarize the precise association between pulmonary tuberculosis (PTB) and P2x7 A1513C gene polymorphism. Methods PubMed and Google Scholar web-databases were searched for the studies reporting the association of P2x7 A1513C polymorphism and PTB risk. A meta-analysis was performed for the selected case–control studies and pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for all the genetic models. Results Eleven studies comprising 2 678 controls and 2 113 PTB cases were included in this meta-analysis. We observed overall no significant risk in all the five genetic models. When stratified population by the ethnicity, Caucasian population failed to show any risk of PTB in all the genetics models. In Asian ethnicity, variant allele (C vs. A: P = 0.001; OR = 1.375, 95% CI = 1.159–1.632) and heterozygous genotype (AC vs. AA: P = 0.001; OR = 1.570, 95% CI = 1.269–1.944) demonstrated significant increased risk of PTB. Likewise, recessive genetic model (CC + AC vs. AA: P = 0.001; OR = 1.540, 95% CI = 1.255–1.890) also demonstrated increased risk of PTB in Asians. Conclusions Our meta-analysis did not suggest the association of P2x7 A1513C polymorphism with PTB risk in overall or separately in Caucasian population. However, it plays a significant risk factor for predisposing PTB in Asians. Future larger sample and expression studies are needed to validate this association.
ABSTRACT
OBJECTIVE@#To summarize the precise association between pulmonary tuberculosis (PTB) and P2x7 A1513C gene polymorphism.@*METHODS@#PubMed and Google Scholar web-databases were searched for the studies reporting the association of P2x7 A1513C polymorphism and PTB risk. A meta-analysis was performed for the selected case-control studies and pooled odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated for all the genetic models.@*RESULTS@#Eleven studies comprising 2678 controls and 2113 PTB cases were included in this meta-analysis. We observed overall no significant risk in all the five genetic models. When stratified population by the ethnicity, Caucasian population failed to show any risk of PTB in all the genetics models. In Asian ethnicity, variant allele (C vs. A: P = 0.001; OR = 1.375, 95% CI = 1.159-1.632) and heterozygous genotype (AC vs. AA: P = 0.001; OR = 1.570, 95% CI = 1.269-1.944) demonstrated significant increased risk of PTB. Likewise, recessive genetic model (CC + AC vs. AA: P = 0.001; OR = 1.540, 95% CI = 1.255-1.890) also demonstrated increased risk of PTB in Asians.@*CONCLUSIONS@#Our meta-analysis did not suggest the association of P2x7 A1513C polymorphism with PTB risk in overall or separately in Caucasian population. However, it plays a significant risk factor for predisposing PTB in Asians. Future larger sample and expression studies are needed to validate this association.