Biotechnological advances have led to a significant increase in beta-carotene levels in leafy vegetables, enhancing their nutritional value without disrupting vital processes like photosynthesis. A recent study published in the Plant Journalreveals that beta-carotene levels in leaves can be increased by up to 30 times through biotechnological methods and exposure to high light intensity. This breakthrough creates new storage areas for beta-carotene that do not interfere with essential functions such as photosynthesis.

Beta-carotene, a key carotenoid, is known for its health benefits, including its antioxidant, immunostimulant, and cognitive-enhancing properties. It also serves as a precursor to retinoids, which are essential for vision, cell proliferation, immune function, and vitamin A production.

The research team, led by Manuel Rodríguez Concepción, a CSIC researcher at the IBMCP, used tobacco plants (Nicotiana benthamiana) as a laboratory model and lettuce (Lactuca sativa) as a cultivation model. They successfully increased beta-carotene content in leaves without compromising photosynthesis. Rodríguez Concepción explains, “Leaves need carotenoids like beta-carotene for proper functioning in the photosynthetic complexes of chloroplasts. When beta-carotene levels are imbalanced, chloroplasts stop functioning, leading to leaf death. Our study achieved the production and accumulation of beta-carotene in non-photosynthetic cellular compartments by combining biotechnological techniques with high light intensity treatments.”

The results show that beta-carotene can be stored in plastoglobules, which are fat storage vesicles found in chloroplasts that do not participate in photosynthesis. This method not only increases the amount of beta-carotene but also its bioaccessibility—meaning it can be more easily extracted and absorbed by the digestive system.

In addition to storing beta-carotene in plastoglobules, the researchers combined this with another approach where beta-carotene accumulates in vesicles located in the cytosol, the liquid surrounding the organelles within cells. This dual strategy resulted in up to a 30-fold increase in accessible beta-carotene, giving the lettuce leaves a distinct golden hue.

According to co-author Pablo Pérez Colao, this discovery of enhanced beta-carotene storage represents a significant advance in the biofortification of vegetables such as lettuce, chard, and spinach, offering a way to boost nutritional content without altering the plants’ natural flavor and aroma.

This research paves the way for biofortifying leafy vegetables, making them a richer source of essential nutrients like beta-carotene, with potential benefits for improving human health on a large scale.

By Impact Lab