Based on the formal framework of reaction systems by Ehrenfeucht and Rozenberg[Fund. Inform. 75 (2007) 263–280], reaction automata (RAs)have been introduced by Okubo et al. [Theoret. Comput. Sci.429 (2012) 247–257], as language acceptors with multiset rewritingmechanism. In this paper, we continue the investigation of RAs with a focus on the twomanners of rule application: maximally parallel and sequential. Considering restrictionson the workspace and the λ-input mode, we introduce the correspondingvariants of RAs and investigate their computation powers. In order to explore Turingmachines (TMs) that correspond to RAs, we also introduce a new variant of TMs withrestricted workspace, called s(n)-restricted TMs. Themain results include the following: (i) for a language L and a functions(n), L is accepted by ans(n)-bounded RA with λ-input mode insequential manner if and only if L is accepted by alog s(n)-bounded one-way TM; (ii) if a languageL is accepted by a linear-bounded RA in sequential manner, thenL is also accepted by a P automaton [Csuhaj−Varju and Vaszil, vol. 2597of Lect. Notes Comput. Sci. Springer (2003) 219–233.] in sequentialmanner; (iii) the class of languages accepted by linear-bounded RAs in maximally parallelmanner is incomparable to the class of languages accepted by RAs in sequential manner.