Structural Characteristics of Extracted Collagen from Tilapia (Oreochromis mossambicus) Bone: Effects of Ethylenediaminetetraacetic Acid Solution and Hydrochloric Acid Treatment

Figures & data

FIGURE 1 X-ray diffractograms of hydroxyapatite (HA), tilapia bone, EDTA treatment tilapia bone, and HCl treatment tilapia bone.

FIGURE 2 (a) FTIR spectra of hydroxyapatite (HA), tilapia bone (CM), EDTA treatment tilapia bone (EDTA), and HCl treatment tilapia bone (HCl); (b) Fourier transform infrared spectrum of HCl-PSC, EDTA-PSC, EDTA-ASC, and type I collagen; (c) Second derivative of amide I band from FTIR spectra of HCl-PSC, EDTA-PSC, EDTA-ASC, and type I collagen.

FIGURE 3 (a) TGA curves for EDTA treatment tilapia bone; (b) TGA curves for HCl treatment tilapia bone.

TABLE 1 Mean amino acid compositions for tilapia bone collagen (residues/1000 residues)^a

	HCl PSC	EDTA ASC	EDTA PSC	Black drum bone	Sheepshead bone	Cold-water fish bone	Warm-water fish bone
Asp	50	44	46	44	43	50	44
Glu	77	72	71	69	66	77	75
Ser	38	36	37	36	34	55	38
His	7	8	7	6	5	9	6
Gly	306	361	365	338	342	340	337
Thr	27	25	25	27	27	25	26
Arg	51	55	56	54	52	52	51
Ala	120	128	125	130	129	109	119
Tyr	4	3	3	2	2	3	3
Cys-s	2	0	1	0	0	−	−
Val	22	22	23	18	18	21	21
Met	10	13	11	12	13	14	13
Phe	14	13	13	13	13	14	13
Ile	13	10	11	6	7	12	11
Leu	24	21	21	20	18	24	22
Lys	24	30	31	26	28	27	26
Pro	130	80	78	107	106	105	110
Hyp	81	80	78	85	88	59	76

Determinations were performed in triplicate and data correspond to mean values;

FIGURE 4 (a) SEM micrographs of the surface morphology of the intact and desalted opercular of tilapia. A1: the intact opercular, A2: the opercular desalinated by EDTA, A3: the opercular desalinated by HCl; (b) SEM micrographs of the section morphology of the intact and desalted opercular of tilapia. B1: the intact opercular, B2: the opercular desalinated by EDTA, B3: the opercular desalinated by HCl.

^aThe literature references for each application are listed in the corresponding sections/subsections.

FIGURE 4 (a) SEM micrographs of the surface morphology of the intact and desalted opercular of tilapia. A1: the intact opercular, A2: the opercular desalinated by EDTA, A3: the opercular desalinated by HCl; (b) SEM micrographs of the section morphology of the intact and desalted opercular of tilapia. B1: the intact opercular, B2: the opercular desalinated by EDTA, B3: the opercular desalinated by HCl.

FIGURE 5 The SDS-PAGE pattern of EDTA-ASC, EDTA-PSC, and HCl-PSC. Lane 1: EDTA-ASC; Lane 2: EDTA-PSC; Lane 3: standard protein; Lane 4: type I collagen; Lane 5: residues in acid solution changed at 1.5 h; Lane 6: residues in acid solution changed at 3.0 h; Lane 7: residues in acid solution changed at 4.5 h; Lane 8: HCl-PSC. Molecular weights from top to bottom in the standard protein are 300, 250, 180, 130, 100, and 70 kDa.

FIGURE 6 (a) CD spectra of the EDTA-PSC treated at different temperatures; (b) Temperature effect on the CD spectra at 223 nm of EDTA-PSC; (c) CD spectra of the HCl-PSC treated at different temperatures.