Enhancing Recombinant Protein Production by Optimising Nutrient Replenishment, Light, and Humidity in a Nicotiana benthamiana Bioreactor

&nbsp;In the past three decades, plant expression systems have been used and found efficient for the production of a variety of recombinant proteins, such as vaccines, therapeutic proteins, enzymes, and antibodies. They have several advantages over other expression systems, such as bacterial, mammalian, and yeast expression systems, in terms of cost-efficiency, speed of the process, ability to make complex proteins, safety (low risk of human contamination), high productivity, and scalability. Plants as bioreactors are capable of producing the desired recombinant proteins with complex structures. High levels of target protein expression in plants are critical for cost-effective pharmaceutical production. Therefore, it is important to develop strategies to increase the expression of target proteins. The expression of recom binant proteins in plants can be influenced by a variety of environmental factors, including nutrients, light, and humidity; therefore, a strategy to optimise their performance efficiency is required. In addition, the amount of different types of nutrients in the medium significantly affects the productivity of the expression process. In this review, we briefly discuss the effects of nutrients, humidity, and light on recombinant protein expression in <em>Nicotiana benthamiana.</em>