Bungala Leonel Tarcisio da Cristina, Park Sang Un, Nguyen Bao Van, Lim Jinsu, Kim Kihyun, Kim Jae Kwang, Park Chang Ha, Le Anh Tuan, Chung Yong Suk, Yeo Hyeon Ji
Department of Crop Science, Chungnam National University, 99 Daehak-ro, Yuseong-gu, Daejeon 34134, Republic of Korea.
Mozambique Agricultural Research Institute, Central Regional Center, Highway N° 6, P.O. Box 42, Chimoio 0606-01, Mozambique.
ACS Omega. 2024 May 22;9(22):23420-23430. doi: 10.1021/acsomega.3c10261. eCollection 2024 Jun 4.
Pakchoi ( subsp. ) is one of the most widely consumed vegetables in Asian countries, and it is high in secondary metabolites. The availability, quantity, and quality of light play a critical role in the growth and development of plants. In this study, we investigated the effect of LEDs (light-emitting diodes; white, blue, red, and red + blue) on anthocyanin, glucosinolates, and phenolic levels in red pakchoi baby leaves. On the 24th day after sowing (DAS), red baby pakchoi leaves were harvested, and shoot length, root length, and fresh weight were measured. Among the different LED treatments, there was no significant difference in shoot length, whereas the highest root length was achieved in the red + blue LED treatment (23.8 cm). The fresh weight also showed a significant difference among the different LED treatments. In total, 12 phenolic and 7 glucosinolate individual compounds were identified using high-performance liquid chromatography (HPLC) analysis. The highest total glucosinolate (2937 μg/g dry wt) and phenolic (1589 μg/g dry wt) contents were achieved in baby leaves exposed to red + blue light. Similarly, the highest contents of total anthocyanins (1726 μg/g dry wt), flavonoids (4920 μg/g dry wt), and phenolics (5900 μg/g dry wt) were achieved in the red + blue treatment. Plants exposed to red + blue LED light showed the highest accumulation of anthocyanin, glucosinolates, and phenolic compounds. For antioxidant activity, DPPH (2,2-diphenyl-1-picrylhydrazylradical) free radical scavenging, ABTS (2,2-azinobis (3-ethylbenzothiazoline)-6-sulfonic acid) radical scavenging, and reducing power assays were performed, and the antioxidant activity of red pakchoi baby leaves grown under red + blue LED light was found to be the best. The metabolic profiling of the identified metabolites revealed distinct separation based on the secondary metabolites. This research will be helpful for farmers to choose the best LED light combination to increase the secondary metabolic content in pakchoi plants.
小白菜（亚种）是亚洲国家消费最为广泛的蔬菜之一，其富含次生代谢产物。光照的可利用性、数量和质量对植物的生长发育起着关键作用。在本研究中，我们调查了发光二极管（LED；白色、蓝色、红色和红 + 蓝）对红梗小白菜子叶中花青素、芥子油苷和酚类物质含量的影响。在播种后第24天（DAS），收获红梗小白菜子叶，并测量茎长、根长和鲜重。在不同的LED处理中，茎长没有显著差异，而红 + 蓝LED处理的根长最长（23.8厘米）。不同LED处理间的鲜重也存在显著差异。使用高效液相色谱（HPLC）分析共鉴定出12种酚类和7种芥子油苷单一化合物。在红 + 蓝光照射下的子叶中，芥子油苷（2937微克/克干重）和酚类（1589微克/克干重）的总含量最高。同样，红 + 蓝处理中总花青素（1726微克/克干重）、类黄酮（4920微克/克干重）和酚类（5900微克/克干重）的含量也最高。暴露在红 + 蓝LED光下的植株花青素、芥子油苷和酚类化合物的积累量最高。对于抗氧化活性，进行了DPPH（2,2 - 二苯基 - 1 - 苦基肼自由基）自由基清除、ABTS（2,2 - 联氮双（3 - 乙基苯并噻唑啉 - 6 - 磺酸））自由基清除和还原能力测定，结果发现红 + 蓝LED光下生长的红梗小白菜子叶的抗氧化活性最佳。所鉴定代谢物的代谢谱显示基于次生代谢物有明显的分离。本研究将有助于农民选择最佳的LED光组合，以增加小白菜植株中的次生代谢物含量。
