UPDATE 1-DataCash adj pretax profit rises; H2 rev to miss view

* H1 adjusted pretax profit rises 22 pct to 7.53 mln stg

* Headline revenue rises 47 pct to 18.0 mln stg

* Increases interim dividend by 25 pct to 5p/shr

* Shares fall 8.2 percent (Adds details)

Sept 15 (Reuters) - British payment service provider DataCash Group Plc DATA.L posted a higher first-half adjusted pretax profit, driven by growth in e-commerce, but said second-half revenue would miss its prior view, hurt by a slowdown in gaming activity.

Gaming transactions have seen slower year-over-year growth, partly because of the lack of a major summer football event this year, DataCash said.

However, the company, which increased its interim dividend by 25 percent to 5 pence a share, expects higher margins in the second half due to an improved product mix.

Adjusted pretax profit rose to 7.53 million pounds ($12.5 million) for the six-month period to June 30, compared with 6.15 million pounds a year ago.

Revenue rose 47 percent to 18.0 million pounds. The recent acquisitions of ACK, ExperCash and The 3rd Man accounted for about 9 percent of the turnover.

Shares of the company were trading down 20.5 pence at 230 pence by 0724 GMT on Tuesday on the London Stock Exchange.

($1=.6021 Pound) (Reporting by Purwa Naveen Raman in Bangalore; Editing by Anne Pallivathuckal)