AIP Conference Proceedings [AIP Publishing THE 8TH INTERNATIONAL CONFERENCE OF THE INDONESIAN CHEMICAL SOCIETY (ICICS) 2019 - Bogor, Indonesia (6–7 August 2019)] THE 8TH INTERNATIONAL CONFERENCE OF THE INDONESIAN CHEMICAL SOCIETY (ICICS) 2019 - Dissolution study of bromelain resulting from partial purification of pineapple stem (Ananas comosus [L.] Merr) encapsulated in chitosan-guar gum and its activity as an antiplatelet