PRIMARY AND SECONDARY METABOLISM, PHOTOSYNTHESIS, AND OXIDATIVE STRESS: FUNDAMENTAL AND APPLIED ASPECTS
Keywords:
: primary metabolism, secondary metabolism, photosynthesis, oxidative stress, reactive oxygen species, antioxidant defence, photoinhibitionAbstract
Reactive oxygen species (ROS) generated in the photosynthetic apparatus play a dual role as both toxic by products and essential signalling molecules under abiotic stress. This review analyses the interconnections between primary metabolism, secondary metabolism, photosynthesis, and oxidative stress mechanisms. Recent evidence shows that metabolic flux is redirected from primary to secondary pathways during stress, increasing the production of phenolics, terpenoids, and alkaloids [1–3]. The balance between PSII photoinhibition and repair is governed by ROS signalling and antioxidant enzymes (SOD, CAT, APX, GR) [4]. Key research gaps include quantitative modelling of metabolic flux, differentiation of ROS signals under combined stresses, and translation of laboratory findings to field conditions. Biotechnological tools such as CRISPR/Cas9 offer promising routes to improve stress tolerance and secondary metabolite yield [5].
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