Natural sweetener producer PureCircle's share price received a boost on Wednesday from the news that Coca-Cola Life, a new lower calorie drink, is to be launched in the UK.Coca-Cola Life, the first new Coca-Cola product in the UK since Coca-Cola Zero was launched in 2006, will contain 36% fewer calories than the full sugared version due to a sugar reduction achieved via the use of stevia leaf extract."We believe that PureCircle will be the supplier of the latter and industry sources suggest this will be on an exclusive basis," said Numis Securities analyst Charles Pick.He said that, after a quiet few months for news flow, the launch will be a positive for PureCircle and has upgraded his rating on the stock from 'reduce' to 'hold'."This is good news for PureCircle as it seeks to ensure that the use of stevia becomes mainstream," Pick said.He said that Coca-Cola Life would be a "minor negative" for Britvic and to a lesser extend AG Barr.BC