Gynura procumbens, commonly known as ‘sambung nyawa’ in Malaysia has been used
traditionally as remedies for anti-inflammatory, anti-hyperlipidimic and anti-hyperglycemic. The
purpose of the present study was to qualitatively evaluate the antimicrobial effects of Gynura procumbens extracts. effects of the sample were determined by disc diffusion method against two bacteria and two fungi namely E. coli, S. aureus, C. albicans and S. cerevisiae. The results showed that the acidic extract of G. procumbens has positive reactions towards E. coli, S. aureus and C. albicans with the presence of zone of inhibition at the concentration of 150 mg/mL. Following the positive reaction, the minimum inhibitory concentration (MIC) of the acidic extract was then evaluated by broth dilution method. The MIC of E. coli and S. aureus were determined at concentration 37.5 mg/mL and 75 mg/mL for C. albicans. It indicated that acidic extracts at lower concentration could inhibit the bacteria, but high concentration of extracts was required in the inhibition of the fungi. It can be concluded that, the present study proves that there is potential of antimicrobial effects in Gynura procumbens leaves extracts.
Introduction: Piper sarmentosum is one of the herbaceous plants that has been used as natural antioxidant to source to treat diseases. This study was conducted to determine the total phenolic contents (TPC) and free radical scavenging capacity in free and bound (soluble and insoluble) of P. sarmentosum. Methods: Free phenolic extract was acquired through direct methanol extraction while acidic and alkaline hydrolyses were adopted to release the bound phenolic acids. The TPC was determined by using Folin-Ciocalteu assay and is expressed as Gallic Acid equivalent (GAE) in miligrams per gram of extracts. The antioxidant scavenging capacity was determined by using DPPH (2, 2-diphenyl-1-picrylhydrazyl) assay. Results: Insoluble bound phenolic extract of P. sarmentosum showed the highest TPC value (1.54 ± 0.04 mg GAE/g DW) followed by soluble phenolic extract and free extract (1.13 ± 0.10 and 0.57 ± 0.06 mg GAE/g DW, respectively). The soluble phenolic fraction has expressed the highest free radical scavenging capacity (76.57± 4.12%) followed by insoluble (69.79± 2.33 %) and free extracts (58.15± 4.44 %). The IC50 values for free, soluble and insoluble bound phenolic were 24.05 ± 3.81, 16.17 ± 1.84 and 18.49 ± 1.92 mg/ml, respectively. Conclusions: The significant differences between all the extracts and antioxidant inhibition in this present study suggested that different forms (free and bound) of extracts did influence the radical scavenging capacity as a whole.
Introduction: Clinacanthus nutans is used as natural nutraceuticals for prevention and treatment of cancer. The purpose of this study is to (i) determine the total phenolic content and antioxidant scavenging capacities of C. nutans in free and bound phenolic acid and (ii) study the relationship between TPC and antioxidant scavenging capacities of C. nutans. Methods: The total phenolic contents were measured using Folin-Ciocalteu assay. Free and bound phenolic were examined by using spectrophotometer while antioxidant capacity were evaluated using DPPH (2, 2-diphenyl-1-picrylhydrazyl) scavenging activity assay. Results: Insoluble phenolic acids showed the highest amount of total phenolic content in C. nutans extracts (6.09+ 0.45 mg gallic acid equivalent (GAE)/ g DW) and exhibited highest antioxidant activity (73.3+0.82 %) as compared to free and soluble phenolic extracts. The IC50 values for free phenolic, soluble bound and insoluble bound phenolic extracts were 0.69+0.02 mg/mL, 0.64+0.04 and 0.60+0.006 mg/mL, respectively. There were positive correlation between insoluble bound phenolic content of C. nutans extracts with antioxidant radical scavenging capacity (R2 = 0.893). Conclusions: These results indicate that different phenolic acid forms affect the total phenolic content and antioxidant properties. Natural compounds such as phenolics from C. nutans could be a good source of antioxidant.