Table 6. Antioxidant joint action of ascorbic acid (A₁) and trolox (A₂) on crocin oxidation.

independent action				concentration addition
		null interaction	synergy			null interaction	synergy
response	K1	0,880±0.110	0,830±0.093	joint	K	1.021±0.074	0,988±0.019
to A1	m1	0,150±0.038	0,154±0.039	response	m	0.263±0.038	0,304±0.024
	a1	0,777±0.232	0,667±0.124		a	0.853±0.164	0,663±0.063
response	K2	0,883±0.146	0,922±0.084	relative potency	u	-	-
to A2	m2	0,260±0.073	0,332±0.057	A1 altering	b2D	-	-
	a2	1,009±0.286	0,909±0.099	eff. conc. of A2	c2D	-	-
A1 as perturbing	b2k	-	-	A2 altering	b1D	-	-
factor for	c2k	-	-	eff. conc. of A1	c1D	-	8.227±2.235
params. of the	b2m	-	-	A1 as perturbing	b2k	-	-
response to A2	c2m	-	2.619±0.892	factor for	c2k	-	-
A2 as perturbing	b1k	-	-	params. of the	b2m	-	-
factor for	c1k	-	-	joint response	c2m	-	-
params. of the	b1m	-	-	A2 as perturbing	b1k	-	-
response to A1	c1m	-	-	factor for	c1k	-	-
comp/coop	s	-	0.980±0.038	params. of the	b1m	-	-
	adj. r2	0.951	0.9932	joint response	c1m	-	-
					adj. r2	0.9195	0.9811
res.sk.		−0.827	0.335	res.sk.		−0.969	−0.677

Hypotheses of null interaction and synergy are compared, under the suppositions of independent action and concentration addition, through the fitting of the experimental results to the respective generalized models. Adj. r²: coefficient of multiple determination; res. sk.: residual skewness. See Figure 11 and text for details.