Commonly, thereare three types of microorganism that found in activated sludge treatment whichis bacteria (95%), protozoa (4%) and metazoan(1%).Basically, three are threetypes of agar that used to grow the microorganism because this sample was anunknown source. (Luo et al.
, 2014).The agar was used is nutrient agar,MacConkey agar, and PDA.(Glymph et al., 2012).
In figure 4.8,4.9 and 5.
1 wasshown under the microscopic and from that was identify the types of shapes forthis three types of microorganisms was bacteria according to the shape. Formicroorganisms, A in figure 4.8 is bacillus(rod) and this microorganism wasgrown on MacConkey agar.
MacConkey agar is a selective and differential culturemedia commonly used for the isolation of enteric Gram-negative bacteria and thegram staining analysis was already which the result obtained was gram negative.Gram-negative enteric bacteria that grow on MacConkey agar are differentiatedby their ability to ferment lactose. If the lactose is fermented by thebacteria, the production of the acid drops the pH of the media. The drop in pHis indicated by the change of neutral red indicator to pink. (Jianlan et al., 2015). So, can prove that thesemicroorganisms which are A were bacteria.
While in figure4.9 was illustrated as microorganisms B and in figure 5.1 was shown as the microorganism B.Then, the image wasobtained under the microscope with 1000x of magnification and it can identifythe shape of this microorganism which is for both microorganisms B and C iscoccus sphere.
From this characteristics, can assume that both of thismicroorganisms are bacteria. (Luo et al., 2014).For microorganisms B, nutrientagar was used as a medium for this microorganism. Nutrient Agar is a generalpurpose, nutrient medium used for the cultivation of microbes supporting thegrowth of a wide range of non-fastidious organisms.
Nutrient agar is popularbecause it can grow a variety of types of bacteria and fungi, and contains manynutrients needed for the bacterial growth. Then, in figure5.1 as the microorganisms, C has used PDA agar as a medium to grow.PotatoDextrose Agar (PDA) is used for the cultivation of fungi. Potato Dextrose Agar(PDA) is a general purpose medium for yeasts and molds that can be supplementedwith acid or antibiotics to inhibit bacterial growth but for this study, theantibacterial was not added, so it possible the microorganisms that grow at PDAwas bacteria.
(Luo et al., 2014).It is because the main characteristic of fungiis has a spore.In this study, the microorganisms that grow in PDA does not haveany spore.So, it was assumed that microorganisms C also the bacteria.