Factors affecting antimicrobial activity of Synechococcus leopoliensis

Abstract

An antimicrobial agent is produced by the cyanobacterium Synechococcus leopoliensis which was found to be active against the Gram-positive bacterium Staphylococcus aureus. The effects of temperature, pH, incubation period, some media and different nitrogen and carbon sources on both growth and antimicrobial activity were investigated. Temperature 35 degrees C and pH 8 were the best for growth and antimicrobial agent production and 14 and 15 days of incubation were found to be the best for maximum growth and antimicrobial activity, respectively, in the medium BG-11. No antimicrobial activity could be detected by the use of G medium, moderate activity was recorded with Chu 10 medium, while high activity was reported in BG-11 medium. Leucine was the best nitrogen source for antimicrobial activity, while maximum antimicrobial activity was introduced by using the carbon sources, citrate and acetate. Very high antimicrobial activity could be detected by using the carbon source galactose in combination with the nitrogen source alanine or by using arabinose with methionine.

Effect of Bacterial-algal Biostimulant on the Yield and Internal Quality of Lettuce (Lactuca sativa L.) Produced for Spring and Summer Crop

“…An important property of PGPB is its production of biopolymers, which improve the water-retention capacity of rhizosphere and are reported to be the protection mechanism of PGPB against drought stress (Noaman et al, 2004). Bacteria interactions with plants can influence the supply of nutrients, increase nutrient use efficiency, induce disease resistance, enhance abiotic stress tolerance, and modulate morphogenesis through plant growth regulators (Ahmad et al, 2008(Ahmad et al, ).…”

Cyanobacteria, Lyngbya aestuarii and Aphanothece bullosa as antifungal and antileishmanial drug resources

“…However, antifungal activity is also reported with crude extract and pure compounds from other freshwater cyanobacteria such as Anabaena, Nostoc, Aphanocapsa, Synechocystis, Synechococcus, Oscillatoria, Nodularia, Calothrix [20,21,[36][37][38][39] , while marine cyanobacteria are little explored with regard to antifungal activity except various species of as Leishmania confervoides, Leishmania majuscula [12,13] . This activity was caused due to species specific biomolecules as specific secondary metabolite produces in specific organism and in specific habitat [5][6][7] . In antifungal study pure compound fluconazole was also used as control but its inhibition zone was double time bigger than crude although its concentration was 100 µg/mL.…”

“…The culture of promastigotes (1伊10 6 cell/mL) were inoculated in 24- 1,6,12,24,32,40 and 48 h intervals by counting motile promastigotes and by using tryptan blue in amastigotes.…”

“…Secondary metabolites produced from cyanobacteria are found to be antibacterial, antifungal, antialgal, anticancerous and antimalarial with many more activitys [3,4] . Microbial productions of metabolites are greatly influenced by factors such as pH, temperature, and light intensity [5][6][7][8] . However, species specificity of secondary metabolites is well established [9] .…”

Antibacterial and antifungal activities of essential oils from medicinal plants found in the South Pacific

“…Generally, a similar trend of higher antibacterial activity with increasing concentration of the essential oil was noted in the literature for C. citratus (Onawunmi and Ogunlana, 1986) , E. hortensis and M. koenigii (Bisht and Negi, 2014). However, antibacterial properties of essential oils from selected medicinal plants are not only dependent on the Gram-reaction, as other factors may influence the inhibitory activity including temperature, pH, incubation period, differences in media, and different nitrogen and carbon sources which certainly needs further investigation (Noaman et al, 2004). …”