Optimization of Light Intensity, Temperature, and Nutrients to Enhance the Bioactive Content of Hyperforin and Rutin in St. John’s Wort

Abstract

St. John’s wort (Hypericum perforatum L.) is a medicinal plant that alleviates depression and other disorders due to its abundance of active ingredients. Hyperforin, rutin, and melatonin are the main active, and important, ingredients in St. John’s wort that alleviate depression. In order to investigate the optimal conditions for accumulating these active ingredients, design of experiments and response surface methodology (RSM) was employed in this study. Two-month-old St John’s wort plants were cultivated in growth chambers at varying temperatures, light intensities, and nutrient solution concentrations before analysis by HPLC, for determining differences in hyperforin, rutin, and melatonin content. The results showed that hyperforin and rutin contents were significantly influenced by temperature (18–23 °C) and light intensity (49–147 μmol m−2 s−1 photosynthetic photon flux density (PPFD)), whereas Hoagland’s nutrient solution concentration (25–75%) had little effect. The accumulation of melatonin might not be influenced by cultivation conditions. Light intensity and temperature are easily controlled environmental factors in artificial cultivation, both of which are related to secondary metabolite production in the plant. Based on RSM, the optimal conditions for the accumulation of hyperforin and rutin were obtained. The maximum content of hyperforin was 5.6 mg/g, obtained at a temperature of 19 °C, a nutrient solution concentration of 45%, and a light intensity of 49 μmol m−2 s−1 PPFD. The maximum content of rutin was 3.8 mg/g obtained at a temperature of 18 °C, a nutrient solution concentration of 50%, and a light intensity of 147 μmol m−2 s−1 PPFD. This evaluation of suitable conditions for the accumulation of bioactive compounds in St. John’s wort can be applied to plant factories on a large scale.

A comparison of artificial intelligence techniques for predicting hyperforin content in Hypericum perforatum L. in different ecological habitats

“…Yesaghi (2006) studied three habitats in Iran and determined that carbon and N-rich soil provided more suitable conditions for the vegetative growth of H. perforatum. Kuo et al (2020) and Mir al. (2019) reported a positive correlation between hyperforin content and soil organic carbon and N. Furthermore, the increasing altitude from 1400 to 2800 m led to an increase in hyperforin content from 24 to 27 mg/g, respectively,…”

“…Yesaghi ( 2006 ) studied three habitats in Iran and determined that carbon and N‐rich soil provided more suitable conditions for the vegetative growth of H. perforatum . Kuo et al ( 2020 ) and Mir et al ( 2019 ) reported a positive correlation between hyperforin content and soil organic carbon and N. Furthermore, the increasing altitude from 1400 to 2800 m led to an increase in hyperforin content from 24 to 27 mg/g, respectively, which is inconsistent with the results of Walker et al ( 2001 ), Kleemann et al ( 2014 ) and Xenophontos et al ( 2008 ) who understood there wasn't any significant difference in amount of hyperforin and hypericin in different altitudes. Altitude is well known factor that can significantly impact secondary metabolism and cause variation in quality and quantity of major essential oil components of H. perforatum (Seyis et al, 2020 ).…”

“…For this purpose, a mixture containing acetonitrile and 0.3% phosphoric acid in water at a ratio of 90:10 was used as the mobile phase. Injection volume, flow rate, column oven temperature, and detector wavelength were set at 20 μl, 1.5 ml/min, 30°C, and 273 nm, respectively (Kuo et al, 2020 ). The hyperforin content was calculated using the plotted standard calibration curve (concentration vs. peak area) and expressed as mg/g dry mass following triplicate measurement.…”

“…For this purpose, a mixture containing acetonitrile and 0.3% phosphoric acid in water at a ratio of 90:10 was used as the mobile phase. Injection volume, flow rate, column oven temperature, and detector wavelength were set at 20 μl, 1.5 ml/min, 30 C, and 273 nm, respectively (Kuo et al, 2020).…”

Medicinal Plants in the Treatment of Depression. II: Evidence from Clinical Trials

“…For example, hyperforin, hypericin, pseudohypericin, and flavonoids are the principal components of H. perforatum extracts and are considered to be responsible for the extractsʼ pharmacological effects [20,98]. In fact, these authors specifically cite hyperforin and rutin as the main active ingredients in St. Johnʼs wort that reduce depressive symptoms; however, other authors also described melatonin as a principal component in this species [99]. As frequently occurs in phytotherapy, the synergy between constituents is a vital aspect of efficacy, as evidenced by the fact that the absence of rutin, a common flavonoid, reduces the antidepressant activity [20] while low hyperforin content preparations are effective in the treatment of depression [98].…”