According to Official Guinness Records,
The most cucumbers sliced from a person's mouth with a sword in one minute is 46, and was achieved by Ashrita Furman (USA) at the Sri Chinmoy Centre, Jamaica, New York, USA on 4 September 2017. This record was equaled by André Ortolf (Germany), in Augsburg, Germany, on 17 November 2017. André chose to have two people holding the cucumbers in the mouth for this attempt.
For a complete list of 2017 records, please visit 2017 Guinness Records in Germany.