Variation of Phytochemicals in Leaves of Seven Accessions of Hibiscus sabdariffa Grown under Field, Green Roof, and High Tunnel Conditions

Abstract

The phytochemical composition in the leaves of seven accessions of Hibiscus sabdariffa L. grown under field, green roof, and high tunnel conditions was investigated in the present study. Principle component analysis of freeze-dried leaves using near-infrared (NIR) spectral fingerprinting revealed differences between accessions and the three growing conditions. Under all conditions, NIR fingerprint data of accession PI 286316 showed variation from the other six accessions (PI 256041, PI 267778, PI 273388, PI 275414, Thai red, and UDC green). A detailed investigation of the phytochemical composition of the accessions by high-performance liquid chromatography coupled with diode array and high-resolution mass spectrometry showed the presence of 16 bioactive phenolics. In six accessions, ten phenolics were identified as compared to eight phenolics in accession 286316, six of which from the latter were unique and not previously reported in H. sabdariffa leaves. Only two phenolics, namely neochlorogenic acid and chlorogenic acid, were common in all seven accessions. Total phenolics in samples from the green roof were 12% and 16% higher than those from the field and high tunnel, respectively. Ten free soluble amino acids and three soluble sugars were identified in all accessions. However, total amino acids and sugars in leaves from the field were between 24 and 42% higher than leaves from the green roof and high tunnel. This study shows that H. sabdariffa leaves provide a good source for bioactive phenolics, free amino acids, and sugars, hence, it can be a nutritious addition to meals.

A Targeted and an Untargeted Metabolomics Approach to Study the Phytochemicals of Tomato Cultivars Grown Under Different Salinity Conditions

“…The water extract was derivatized with DEEMM using a previously reported method . Briefly, 200 μL of the extract was transferred to a 2 mL amber glass vial.…”

“…The water extract was derivatized with DEEMM using a previously reported method. 27 Briefly, 200 μL of the extract was transferred to a 2 mL amber glass vial. To this volume, we added 5 μL of derivatization reagent DEEMM, 150 μL of methanol, and 75 μL of borate buffer (0.75 M, pH 9.0).…”

Growing sweet potatoes [Ipomoea batatas (L.) Lam.)] for their greens and the impact on storage roots

“…Food insecurity leads to a variety of negative health outcomes, which can lower overall health and limit daily activities (Gunderson and Ziliak, 2015). Therefore, crops that are high in nutrients and suitable for cultivation in urban areas may help promote positive health outcomes by reducing food insecurity (Jeffery and Richardson, 2021;Luthria et al, 2021).…”