Structural and functional changes in biofilm during adaptation towards amaranth biodegradation

Figures & data

Figure 1. Design of the model biofilter.

Figure 2. Pseudomonas sp. ratio to the total quantity of the microorganisms calculated on the basis of: FISH (a); plate count techniques (b).

Table 1. Technological, microbiological and enzymological parameters of the downflow sand biofilter in: early stage of the model process (0 h. - 191 h), late stage of the model process (191 h – 455 h) and end of the experiment (455 h – 623 h).

		0 h - 191 h			191 h – 455 h			455 h – 623 h
		Upper layer	Middle layer	Bottom layer	Upper layer	Middle layer	Bottom layer	Upper layer	Middle layer	Bottom layer
Technological parameters	Inflow amaranth concentration (mg/L)	10 − 30			30-45			45 − 55
	Effectiveness of amaranth removal (%)	88.35%			90.60%			89.76%
	Rate of amaranth removal (mg/h)	0.413			0.991			1.136
Microbiological parameters (CFU g ^−1)	Aerobic heterotrophs	2.15 × 10^7	1.73 × 10^7	1.23 × 10^7	4.63 × 10^7	2.33 × 10^7	9.93 × 10^6	8.15 × 10^7	5.20 × 10^7	3.20 × 10^7
	Pseudomonas sp.	6.18 × 10^6	1.59 × 10^7	1.05 × 10^7	3.95 × 10^6	9.25 × 10^5	3.50 × 10^5	2.60 × 10^6	2.25 × 10^6	9.15 × 10^5
	Azo-degraders	1.58 × 10^6	3.05 × 10^6	1.90 × 10^6	1.18 × 10^6	8.75 × 10^5	3.50 × 10^5	9.40 × 10^5	3.00 × 10^5	3.05 × 10^5
Enzymological parameters (μmol min^-1mg^-1 protein)	AzoR	10.35	6.93	6.2	3.91	7.40	0.72	6.04	3.7	1.78
	SDH	0.75	0.31	0.35	0.56	0.73	0.64	0.63	0.85	0.59
	C1,2DO	2.03	0.49	1.08	1.75	2.94	2.69	0.88	1.86	2.72

Table 2. Key azo-degrading microorganisms’ ratio to the total quantity of the microorganisms calculated on the base of FISH and standard culture techniques.

	191 h	455 h	623 h
g. Pseudomonas ratio (FISH)	37.73%	23.93%	42.57%
g. Pseudomonas ratio (plate count techniques)	78.99%	5.34%	3.72%
Azo-degraders ratio (plate count techniques)	13.49%	3.27%	0.89%

Table 3. FISH of the biofilm from the three layers in the end of the process.

SAND BIOFILTER – End of experiment (623 h) – concentration of amaranth 45-55 mg L ^−1
		Upper layer	Middle layer	Bottom layer
Fluorecsent images	DAPI (stain for all organisms)
	FISH (Peudomonas sp.)

Data availability statement

The authors confirm that the data supporting the findings of this study are available within the article.