A Chinese herbalist has denied selling remedies containing a banned substance which allegedly resulted in a woman having her kidneys removed.

Zie Zheng stopped selling products containing Aristolochia at her Brighton shop because she knew its use had been prohibited, a jury at Hove Crown Court heard.

David Lamming, defending, said Zheng had been told by the Register of Chinese Herbal Medicines the drug had been shown to cause kidney failure.

It was alleged Zheng had sold four remedies containing Aristolochia to Sandra Stay after she visited the shop in St James's Street over three years.

Mrs Stay suffered renal failure, which resulted in her kidneys being removed last year.

Mr Lamming said subsequent tests showed the pills showed traces of Aristolochia at only 0.004 per cent.

Mr Lamming said: "The banning order was not made until July 1999. Mrs Stay said she went into the shop in October 1998, nine months before the order was made.

"If they were supplied by Zie Zheng, they were not banned at the time Mrs Stay bought them."

After the ban was introduced Zheng instructed her supplier in China not to send any products containing Aristolochia.

When 50 bottles of tablets which did contain it arrived, she changed her supplier.

Mr Lamming said: "This is significant because Zie Zheng will say she can account for all 50 bottles of pills and none of those was sold to Mrs Stay."

Zheng, 37, of St James's Street, Brighton, denies four counts of selling a medicinal product containing a prohibited substance.

The trial continues.