Table 4.

The stability of NNS5-6 AMP against temperatures, proteolytic enzymes, surfactants, and pH treatments was evaluated. The residual activity after each treatment is reported along with the incubation times (mean ± SD; n = 3).

Conditions	% Residual Activity of NNS5-6 AMP against P. aeruginosa TISTR 357
	1 h	6 h	12 h
Effect of Temperatures
Non-treated NNS5-6 AMP	100.00 ± 1.23	100.00 ± 0.70	100.00 ± 0.62
37 °C	99.39 ± 1.98	99.39 ± 0.61	99.69 ± 0.95
40 °C	99.80 ± 0.94	99.19 ± 0.93	99.07 ± 0.72
50 °C	65.16 ± 3.07 *	0.00 ± 0.00 *	0.00 ± 0.00 *
60 °C	0.00 ± 0.00 *	0.00 ± 0.00 *	0.00 ± 0.00 *
80 °C	0.00 ± 0.00 *	0.00 ± 0.00 *	0.00 ± 0.00 *
100 °C	0.00 ± 0.00 *	0.00 ± 0.00 *	0.00 ± 0.00 *
121 °C, 15 psi, 15 min	0.00 ± 0.00 *
121 °C, 15 psi, 30 min	0.00 ± 0.00 *
Effect of Proteolytic enzymes
Non-treated NNS5-6 AMP	100.00 ± 0.95	100.00 ± 0.34	100.00 ± 0.58
NNS5-6 AMP with Proteinase K (1 mg/mL)	96.08 ± 3.41 *	86.58 ± 1.22 *	83.62 ± 1.34 *
NNS5-6 AMP with Trypsin (1 mg/mL)	99.38 ± 1.99	90.47 ± 2.02 *	88.90 ± 1.46 *
NNS5-6 AMP with α-chymotrypsin (1 mg/mL)	99.38 ± 0.95	99.42 ± 1.22	98.46 ± 0.88
Effect of Surfactants
Non-treated NNS5-6 AMP	100.00 ± 0.60	100.00 ± 0.93	100.00 ± 0.61
NNS5-6 AMP with 1% SDS	116.77 ± 1.80 *	122.52 ± 1.86 *	119.19 ± 1.53 *
NNS5-6 AMP with 1% Triton X-100	116.17 ± 0.60 *	120.28 ± 1.53 *	120.81 ± 1.53 *
1% SDS alone	121.76 ± 2.42 *
1% Triton X-100 alone	126.83 ± 2.72 *
Effect of pH variation
Non-treated NNS5-6 AMP	100.00 ± 1.19	100.00 ± 1.28	100.00 ± 0.72
pH 1.2	89.62 ± 1.85 *	83.83 ± 1.72 *	81.14 ± 1.71 *
pH 4.5	97.31 ± 0.33	95.69 ± 1.75	95.62 ± 1.19
pH 6.8	97.31 ± 3.33	96.46 ± 0.57	96.00 ± 0.57
pH 7.4	98.65 ± 0.58	98.18 ± 1.15	98.48 ± 0.66
pH 8.0	99.23 ± 1.15	97.22 ± 0.98	98.48 ± 0.87
pH 10.0	98.85 ± 1.20	97.42 ± 0.82	98.10 ± 1.44
pH 12.0	94.31 ± 0.68 *	93.40 ± 0.78 *	90.10 ± 2.38 *
pH 14.0	90.77 ± 0.88 *	84.40 ± 1.15 *	79.05 ± 1.75 *

* Significance according to Student’s t-test at a p-value < 0.05 compared with non-treated NNS5-6 AMP.