Résumé
Objective: To evaluate the antimicrobial properties of Kappaphycus alvarezii (K. alvarezii) and Andrographis paniculata (A. paniculata) and to compare the microbial inhibition activities between these two crude extracts. Methods: Both K. alvarezii and A. paniculata were extracted with methanol before the commencement of antimicrobial properties studies. There were a total of eight species of bacteria, including Gram-positive bacteria Bacillus cereus, Bacillus subtilis, Staphylo-coccus aureus and Staphylococcus epidermidis and Gram-negative bacteria, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enterica. The antimicrobial activity was tested by disk diffusion method. Results: Crude extract of K. alvarezii was found not effective against both Gram-positive and Gram-negative bacteria. In contrast, A. paniculata showed higher inhibi-tion towards the growth of Gram-positive bacteria compared to Gram-negative bacteria. Results revealed that Bacillus subtilis was susceptible at lower concentration of A. paniculata crude extract however Staphylococcus epidermidis was the most suscep-tible towards A. paniculata at higher concentration. Although the inhibition zones pro-duced by the crude extract were smaller than that of the positive control, streptomycin disc, A. paniculata crude extract still can be considered as potential antimicrobial agents either because it is a natural product or the active compound which is yet identified from its crude extract. Conclusions: Crude extract of K. alvarezii has zero inhibition in bacteria growth whereas A. paniculata exerted higher inhibition towards Gram-positive bacteria. The bioactive compounds contained by A. paniculata can be evaluated in order to yield a better vision towards the mode of action.
Résumé
Seaweed contains various nutrients that has the potential to be a source of nutritious food, but only a few studies done on the red seaweeds in Malaysia. Therefore, this study was conducted to determine the macronutrients content, amino acid profile and fatty acid component in Kappaphycus alvarezii and Kappaphycus striatum. The study found that the range of moisture, fat, ash, protein, fiber and carbohydrates content for both red seaweeds were 6.9% - 7.3%, 0.5% - 2.6%, 29.4% - 30.9%, 2.5% - 5.7% , 5.3% - 5.5% and 50.1% - 53.3% respectively. A total of 16 amino acids were identified in which the essential amino acid for K. alvarezii and K. striatum were 41.11% and 36.15% respectively. A total of 34 fatty acids were identified in which the content of saturated fatty acids (SFA) was the highest (42.7% - 72.8%), followed by mono-unsaturated fatty acid (MUFA) (13.8% - 36.2%) and polyunsaturated fatty acids (PUFAs) was the lowest (13.5% - 21.2%). In conclusion, this study suggest that K. alvarezii and K. striatum are potentially be used as raw materials or food ingredients to improve the nutritional value of the human diet.
Résumé
Objective To evaluate the antimicrobial properties of Kappaphycus alvarezii (K. alvarezii) and Andrographis paniculata (A. paniculata) and to compare the microbial inhibition activities between these two crude extracts. Methods Both K. alvarezii and A. paniculata were extracted with methanol before the commencement of antimicrobial properties studies. There were a total of eight species of bacteria, including Gram-positive bacteria Bacillus cereus, Bacillus subtilis, Staphylococcus aureus and Staphylococcus epidermidis and Gram-negative bacteria, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Salmonella enterica. The antimicrobial activity was tested by disk diffusion method. Results Crude extract of K. alvarezii was found not effective against both Gram-positive and Gram-negative bacteria. In contrast, A. paniculata showed higher inhibition towards the growth of Gram-positive bacteria compared to Gram-negative bacteria. Results revealed that Bacillus subtilis was susceptible at lower concentration of A. paniculata crude extract however Staphylococcus epidermidis was the most susceptible towards A. paniculata at higher concentration. Although the inhibition zones produced by the crude extract were smaller than that of the positive control, streptomycin disc, A. paniculata crude extract still can be considered as potential antimicrobial agents either because it is a natural product or the active compound which is yet identified from its crude extract. Conclusions Crude extract of K. alvarezii has zero inhibition in bacteria growth whereas A. paniculata exerted higher inhibition towards Gram-positive bacteria. The bioactive compounds contained by A. paniculata can be evaluated in order to yield a better vision towards the mode of action.
Résumé
Kappaphycus alvarezii (Rhodophyta, Gigartinales) is a red algae widely cultivated as the main source of raw material for the carrageenan industry. This hydrocolloid is normally used in the food industry as a gelling and stabilizing agent. The facility of its commercial farming based on vegetative propagation promoted the success of the aquaculture of this macroalgae that consequently stimulated studies focusing on new potential uses of this resource. This work presents a brief review of the studies related to K. alvarezii cultivation in southern and southeastern Brazil, the latest discoveries in the world concerning pharmacological studies with this species and the advantages of the use of carrageenan as a source of dietary fiber, cholesterol reducer, and antioxidant, anti-viral and anti-cancer compounds, as well as the effects in hemagglutination activity.