Enhancement of antimicrobial activities of whole and sub-fractionated white tea by addition of copper (II) sulphate and vitamin C against Staphylococcus aureus; a mechanistic approach

Table 1 The antimicrobial effect of different levels of copper (II) sulphate against S. aureus NCTC 06571 after 30 minute incubations at room temperature

Concentration of copper (II) sulphate added in assay*	Typical approximate reduction in viability following 30 minute exposure log ₁₀ cfu mL^-1 (SEM)
0 μM	N/A
0.56 μM*	N/A
1.00 μM	~0.75 (± 0.74)
4.8 mM	~2.50 (± 0.68)
9.6 mM	~3.50 (± 0.69)

N/A = not applicable as no reduction was seen. * Equivalent concentration to copper level found in whole white tea extract (0.14 mg L^-1) by ICP-AES. SEMs shown in brackets.

ISSN: 2662-7671