ABSTRACT
Aims@#Cyanbacterial bloom can cause unpleasant smell and taste. It can also produce toxins that can be harmful to animals or human. The capability of plant materials to control cyanobacterial bloom has been reported by many researchers. Among the plant materials were barley straw, banana skin, orange peel and many more. It was also showed that the ability of the plant material, especially barley straw to control cyanobacteria might likely involved complex microbial degradation and enhanced by fungal degradation. Therefore, experiments were set up to test the effect of fungi-degraded palm oil trunk on cyanobacterial growth. @*Methodology and results@#In the study, 1 g of palm oil trunk was pre-treated with fungus Lichtheimia sp, for 30 days to allow degradation to occur. After the incubation, the fresh and degraded palm oil trunk was introduced to cyanobacterial culture for 30 days. Growth of culture were estimated based on its chlorophyll a concentration. This study showed an increase ability of fungi-degraded palm oil trunks in inhibiting cyanobacterial growth. @*Conclusion, significance and impact of study@#The results strengthened the theory of involvement of microbial degradation in controlling cyanobacterial growth.
ABSTRACT
@#Aims:This study focus on the presence of cyanobacterial toxin in Malaysia and anatoxin-a-encoding gene was detected in this study and the status of cyanobacterial toxins in Malaysia can now be clarified.Methodology and results:As part of status determination of cyanobacterial toxins in Malaysia, cyanobacterial strains have been isolated from different environments and identified using cyanobacterial16S rRNA gene sequence. PCR assay was carried out to detect the presence of cyanobacterial toxin-encoding genes in these isolated strains by amplifying genes encoded for microcystin, anatoxin-a, cylindrospermopsin and saxitoxin. Using molecular identification of 16S rRNA gene sequences, a total of forty-two cyanobacterial strains were identified, which belongs to eighteen different genera of Synechococcus, Cyanobium, Synechocystis, Chroococcidiopsis, Leptolyngbya, Nodosilinea, Limnothrix, Pseudanabaena, Cephalothrix, Aerosakkonema, Oscillatoria, Alkalinema, Pantanalinema, Planktolyngbya, Scytonema, Nostoc, Hapalosiphonand Symphyonemopsis. The toxicity of these strains was tested using PCR amplification of toxin-encoding genes using specific primers.Conclusion, significance and impact of study:Anatoxin-a (ATX) gene,which involved in the biosynthesis of anatoxin-Awas detected in two isolated strains namelyLimnothrixsp. B15 and Leptolyngbyasp. D1C10.This study focus on the the presence of cyanobacterial toxin in Malaysia can now be determined as potential threat because anatoxin-a-encoding gene was detected in this study and the status of cyanobacterial toxins in Malaysia can now be clarified.
ABSTRACT
@#Aims:The effectiveness of microalgae in the post-treatment of palm oil mill effluent (POME) was being investigated for colourremoval and COD reduction. Methodology and results:Raw POME, obtained from a local palm oil mill and treated with anaerobic and aerobic processes for 50 days and 16 days of hydraulic retention time (HRT) respectively, was then used in the phycoremediation study. Three different species of microalgae (Ankistrodesmus falcatus, Scenedesmus sp. and Chlorellasp.) were inoculated in a culture media which contained 20%, 40% and 60% dilution of POME. The pH of thetreated POME sample was not adjusted and fixed at the original pH of about pH 8-9. The growth of the microalgae was determined every 2 days based on their chlorophyll concentration. Chlorellasp. showed the best adaptation and grew well in all dilutions of the treated POME sample and subsequently chosen for remediation of the POME sample without any dilution.Conclusion, significance and impact of study:Chemical oxygen demand (COD) and colour removal of POME were determined every 2 days. Chlorellasp. performed well with COD reduction and colour removal of 67.87% and 53.26%, respectively.