A Review of Bryophytes: Enzymatic and Non-Enzymatic Antioxidants as a Key for Their Pharmacological Potential and Green-Biotechnological Application

Bryophytes, as early land plants, have evolved and developed a wide array of enzymatic and non-enzymatic antioxidant defense mechanisms to cope with oxidative stress. This review explores the intricate biochemical pathways of bryophyte antioxidant defense including their secondary metabolite (SM) systems and protective enzymes such as superoxide dismutase (SOD), catalase (CAT), glutathione transferases (GSTs), glutathione peroxidase (GPx), and glutathione reductase (GR). These metabolic components function through species-specific regulatory mechanisms related to expression way. The pharmacological significance of bryophyte-derived compounds is also highlighted, supported by recent discoveries of numerous bioactive molecules, such as melatonin, cannabinoids, and specific chemical marker compounds. Most current biochemical studies on bryophytes focus on their desiccation tolerance and their utility as pollution indicators; however, another aim of this review is to underscore their broader pharmacological promise. Furthermore, this paper explores the biotechnological applications of bryophytes in drug discovery and the need for bioreactor cultivation of the species used. It also emphasizes the need for further investigation into bryophyte biochemistry and enzymology, particularly their unique enzyme systems, to fully unlock their therapeutic potential.