Characterization of Phytochemical Components of Crocus sativus Leaves: A New Attractive By-Product

Abstract

Crocus sativus L. is one of the world’s most famous saffron production crops and its enormous by-products, such as leaves, are an excellent source of bioactive compounds with potential nutritional applications. The total phenolic content of Crocus leaves was 5.44 ± 0.01 mg GAE/g, and the total flavonoid content was 2.63 ± 0.05 mg RE/g, respectively. The main bioactive compounds in the leaves, such as polyphenols, flavonoids by HPLC and carboxylic acids, and amino acids, were also identified by GC-MS. HPLC analyses revealed mangiferin as a dominant constituent (1.26 ± 0.02 mg/g). C. sativus contains seven essential amino acids (ILE, LEU, LYS, MET, PHE, THR, TRP, VAL) in high concentration. Among them, isoleucine (7965 µg/g) was the dominant compound. In addition, the K and Ca concentrations in the leaves were significant (p < 0.05). The chemical composition revealed α-linolenic acid (22,490 µg/g) and linoelaidic acid (9880 µg/g) to be major constituents among all the acids found in the Crocus leaves. The extracts of C. sativus leaves showed the highest inhibitory activity for Gram-positive (B. subtilis and S. aureus) bacteria in the in vitro assay. The current results identify and underline the potential of natural products from C. sativus leaves that can add value to saffron production.

Comparative analysis of apocarotenoids and phenolic constituents of Crocus sativus stigmas from 11 countries: Ecological impact

“…[ 45 ] Analysis of the amino acid composition of C. sativus stigma showed the presence of L‐tyrosine (326.6 µg/g) and the absence of L‐phenylalanine. [ 46 ] Similar data were obtained by Priscila del Campo et al [ 47 ] In this case, it can be assumed that the biosynthesis of phenolic acids in Crocus stigma proceeds along the arogenate pathway [ 48 ] through prephenate, arogenate, and tyrosine (Figure 3).…”

“…The method of obtaining saffron extracts and antibacterial assay has been described previously. [29,72] Briefly, crushed C. sativus stigma (Ukraine, Kherson) was macerated with hot distilled water (80°C)/80% ethanol (1:100), kept in a dark place for 24 h, then the extract was filtered. The maceration was repeated two more times with the residue under the same conditions.…”

A New Glycosyltransferase Enzyme from Family 91, UGT91P3, Is Responsible for the Final Glucosylation Step of Crocins in Saffron (Crocus sativus L.)

“…For these reasons, the expression patterns of the identified genes were analyzed in several tissues, including the stigma at different developmental stages, revealing that the genes for 3 of them (UGT91K2, UGT91K3 and UGT91P3) had expression patterns closely resembling those of the previously characterized UGT74AD1. Furthermore, the co-correlation analyses with crocin levels in different developmental stages highlighted UGT91P3 and UGT91K3 as the best candidates, albeit only UGT91P3 showed higher expression levels in the stigma compared with other tissues, whereas UGT91K3 was characterized by higher expression levels in leaves, where crocins are not produced, thus suggesting that other metabolites act as substrates for UGT91K3 [34,35] in saffron vegetative tissues.…”

Pharmacological Potential and Chemical Composition of Crocus sativus Leaf Extracts

“…Previous phytochemical analysis of C. sativus leaves from Ukraine showed the presence of flavonoids ( trans -cinnamic acid, chlorogenic acid, kaempferol, ononin, irigenin, and mangiferin), as well as amino acids and carboxylic acids in the plant raw material [ 24 ]. Therefore, further research was devoted to establishing the chemical composition of the dry C. sativus leaf extracts aiming to reveal their effect on the pharmacological activity of the extracts.…”