𝐁𝐨𝐨𝐬𝐭𝐢𝐧𝐠 𝐕𝐢𝐭𝐚𝐦𝐢𝐧 𝐊𝟏 𝐢𝐧 𝐈𝐧𝐝𝐨𝐨𝐫 𝐋𝐞𝐭𝐭𝐮𝐜𝐞 𝐰𝐢𝐭𝐡 𝐔𝐕-𝐀 𝐋𝐢𝐠𝐡𝐭𝐢𝐧𝐠

A recent study tested whether 𝐔𝐕-𝐀 𝐥𝐢𝐠𝐡𝐭 (389 nm) can increase phylloquinone (vitamin K1) in romaine lettuce.

🔎 𝐊𝐞𝐲 𝐟𝐢𝐧𝐝𝐢𝐧𝐠𝐬:

• Short-term UV-A exposure during the stationary growth phase increased 𝐯𝐢𝐭𝐚𝐦𝐢𝐧 𝐊𝟏 levels by +𝟏𝟕𝟒%.

• This came with a 𝟐𝟒% 𝐝𝐫𝐨𝐩 𝐢𝐧 𝐟𝐫𝐞𝐬𝐡 𝐰𝐞𝐢𝐠𝐡𝐭, but no significant loss in dry weight.

• Long-term UV-A exposure boosted vitamin K1 too—but reduced overall growth.

• Enhanced vitamin K1 likely serves as 𝐩𝐡𝐨𝐭𝐨𝐩𝐫𝐨𝐭𝐞𝐜𝐭𝐢𝐨𝐧, not improved photosynthesis.

💡 𝐏𝐫𝐚𝐜𝐭𝐢𝐜𝐚𝐥 𝐭𝐚𝐤𝐞𝐚𝐰𝐚𝐲 𝐟𝐨𝐫 𝐠𝐫𝐨𝐰𝐞𝐫𝐬:

• Consider 𝐬𝐡𝐨𝐫𝐭 𝐔𝐕-𝐀 𝐬𝐮𝐩𝐩𝐥𝐞𝐦𝐞𝐧𝐭𝐚𝐭𝐢𝐨𝐧 𝐛𝐞𝐟𝐨𝐫𝐞 𝐡𝐚𝐫𝐯𝐞𝐬𝐭 to add nutritional value without severely compromising yields.

• 𝐅𝐢𝐧𝐞-𝐭𝐮𝐧𝐢𝐧𝐠 𝐔𝐕-𝐀 𝐥𝐞𝐯𝐞𝐥𝐬 (lower than the 40% tested here) 𝐦𝐚𝐲 𝐬𝐭𝐫𝐢𝐤𝐞 𝐚 𝐛𝐞𝐭𝐭𝐞𝐫 𝐛𝐚𝐥𝐚𝐧𝐜𝐞 𝐛𝐞𝐭𝐰𝐞𝐞𝐧 𝐛𝐢𝐨𝐦𝐚𝐬𝐬 𝐚𝐧𝐝 𝐧𝐮𝐭𝐫𝐢𝐞𝐧𝐭 𝐞𝐧𝐡𝐚𝐧𝐜𝐞𝐦𝐞𝐧𝐭.

• This could help differentiate your produce in the market by offering 𝐯𝐚𝐥𝐮𝐞-𝐚𝐝𝐝𝐞𝐝, 𝐧𝐮𝐭𝐫𝐢𝐞𝐧𝐭-𝐫𝐢𝐜𝐡 𝐠𝐫𝐞𝐞𝐧𝐬.

📈 With consumer demand for nutrient-dense foods growing, a small tradeoff in yield could mean a higher price point and stronger market positioning.

👉 Would you integrate UV-A into your lighting strategy to enhance crop nutrition?

📚 Source: Kong Y, Nemali K (2025) Enhancing phylloquinone levels using ultraviolet-A radiation in indoor farming. 𝑃𝐿𝑜𝑆 𝑂𝑁𝐸 20(4): e0319469.

Dr. Michele Grieco turned his plant biology expertise into Plant Monitor - affordable monitoring apps bringing research-grade measurements to small greenhouses and vertical farms.

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