Table S3. Pearson’s correlation coefficient between of total polyphenols, oxalic acid and nitrates (determined spectrophotometrically), antioxidant activity, antidiabetic activity and pH in predigested spinach lemon juice formulations.

Predigested sample	TP/(mg/g)	TF/(mg/g)	TPA/(mg/g)	OA/(mg/g)	Nitrate/(mg/g)	DPPH/%	DPPH/(μmol/g)	FRAP/%	FRAP/(μmol/g)	α-amylase/%	pH
TP/(mg/g)	1.000
TF/(mg/g)	0.233	1.000
TPA/(mg/g)	0.616	0.524	1.000
OA/(mg/g)	0.670	0.377	0.823	1.000
Nitrate/(mg/g)	0.440	0.729	0.666	0.693	1.000
DPPH/%	0.584	0.817	0.756	0.806	0.925	1.000
DPPH/(μmol/g)	0.685	0.723	0.836	0.788	0.900	0.950	1.000
FRAP/%	0.890	0.319	0.648	0.835	0.667	0.748	0.766	1.000
FRAP/(μmol/g)	0.850	0.279	0.705	0.786	0.705	0.725	0.848	0.905	1.000
α-amylase/%	0.833	0.076	0.712	0.730	0.529	0.548	0.725	0.834	0.959	1.000
pH	-0.652	-0.780	-0.747	-0.738	-0.929	-0.970	-0.978	-0.780	-0.811	-0.651	1.000

Bold values are significant at p≤0.05. TP=total polyphenols, TF=total flavonoids, TPA=total phenolic acids, OA=oxalic acid, DPPH=2,2-diphenyl-1-picrylhydrazyl, FRAP=ferric ion reducing antioxidant power, φ(lemon juice)=0, 2, 5, 10 and 20%