Low Temperatures Affect the Physiological Status and Phytochemical Content of Flat Leaf Kale (Brassica oleracea var. acephala) Sprouts

Abstract

Consumption of plants in the juvenile stage becomes popular because sprouts are easy to grow, and they can be a tasty source of micro- and macro-nutrients and various phytochemicals. However, some environmental factors during sprout growth can affect their characteristics. In this article, we investigated how low temperatures during cultivation (8 °C) and additional exposure to freezing temperatures (−8 °C) affect the physiological status and phytochemical content of kale (Brassica oleracea var. acephala) sprouts compared to the control grown at 21 °C. We conducted five independent laboratory experiments and found that low temperature significantly increased proline content and decreased sprouts yield. In addition, low temperature caused a significant decrease in carotenoid and flavonoid content, while phenolic acid content and total glucosinolates content increased, but individual glucosinolates were differentially affected. Our results indicate that low temperatures affect the physiological status of kale sprouts and affect the content of phytochemicals.

Adjustments of the Phytochemical Profile of Broccoli to Low and High Growing Temperatures: Implications for the Bioactivity of Its Extracts

“…This is consistent with previous research on the subject and may also be attributed to the fact that chlorophyll b undergoes faster degradation, ultimately transforming into chlorophyll a as part of the breakdown process [56,57]. A reduction in total chlorophyll content under temperature stress has already been observed in other plant species, e.g., broccoli [34], cabbage [56], kale [56,58], Thalassia hemprichii [59], watermelon [60], and squash [61]. These results indicate the sensitivity of chlorophyll a and b to temperature, whether increased or decreased.…”

Sprouts and Microgreens—Novel Food Sources for Healthy Diets

“…acephala) exposed to low-temperature stress (growth temperature of 8 • C with intermittent freezing for one hour at −8 • C) increased the total content of phenolic acids and glucosinolates. However, such a treatment should be used with caution, as it also led to a significant decrease in the content of carotenoids and total flavonoids [121].…”

The Developmental Delay of Seedlings With Cotyledons Only Confers Stress Tolerance to Suaeda aralocaspica (Chenopodiaceae) by Unique Performance on Morphology, Physiology, and Gene Expression

“…Interestingly, the proline content in seedlings developed in spring ( Figure 5A ) was about 5 times lower than that in the winter seedlings ( Figure 10A ), which may be the effect of seasonal temperature fluctuation on the seedlings, and we also detected such a change in other experiments (data not shown). In Brassica oleracea , low temperature can also cause increase in the proline content of sprout (Šamec et al, 2022 ). Upon stress, plant cellular homeostasis is disrupted, accompanying with the generation of ROS (e.g., H 2 O 2 and ), which may cause peroxidation of membrane lipids and increase MDA concentration (Liu et al, 2021 ).…”