Assessment of Dietary Bioactive Phenolic Compounds and Agricultural Sustainability of an African Leafy Vegetable Corchorus olitorius L.

Abstract

Corchorus olitorius L. is an African leafy vegetable of high nutritional interest. To assess its agricultural suitability to sustainable cultivation conditions and its potential benefits for human nutrition, its phytochemical content in response to conservation agriculture practices [i.e., no-tillage (NT) and cover crop maintenance] and low water regime were evaluated and compared with response under conventional agriculture management. Hydric stress and NT did not affect the content of antioxidant metabolites, compared to conventional agricultural practices. In both conditions, leaves were found to be a great source of phenolic compounds. The effect of these phenolic fractions was assessed on two colon cell phenotypes to evaluate putative nutraceutical properties. Polyphenol-enriched extracts (PEEs) displayed selective cytotoxic activities against tumor Caco-2 cells but not on the healthy CCD841 line. PEEs were able to trigger oxidative stress and to inhibit the activity of glutathione-independent antioxidant enzymes on Caco-2 cells. C. olitorius showed to be a promising crop for improving both agricultural sustainability and health benefits due to the great amount of antioxidant compounds in leaves, whose occurrence is not altered by stressful farming conditions. Given its high adaptability, the cultivation of this crop is therefore recommendable also in the Mediterranean Basin.

A Comprehensive Review of C. capsularis and C. olitorius: A Source of Nutrition, Essential Phytoconstituents and Pharmacological Activities

“…Phenolic acids are cyanidin and cyanidin glucosides from the bark and leaf of C. capsularis whereas astragalin, tolifolin, isoquercitin, and jugulanin come from C. olitorius leaves, as reported by researchers [ 47 , 48 ]. From the leaves of C. olitorius , a number phenolic compounds such as chlorogenic acid (383.9 mg/100 g FW), 3,5-dicaffeoylquinic acid (102.1 mg/100 g), quinic acid, gallic acid, protocatechuic acid, 4- O -caffeoylquinic acid, caffeic acid, 1,3-di- O -caffeoylquinic acid, feruloyl-quinic acids, and 4,5-di- O -caffeoylquinic acid were identified [ 47 , 49 ]. According to the literature, chlorogenic acid may be the most predominant antioxidant [ 45 , 47 , 50 ], whereas caffeoylquinic acids and dicaffeoylquinic acids have been reported to inhibit human low-density lipoprotein oxidation in vitro; there are limited studies investigating the effects in vivo [ 51 , 52 ].…”

“…The leaves of C. olitorius contain flavanones (naringenin, naringin), flavones (cirsilineol and cirsiliol), flavones glycosides (apigenin, apegenin-7- O -glucoside), tolifolin (kaempferol-3- O - β -D-galactopyranoside), astragalin (kaempferol-3- O - β -D-glucopyranoside), and jugulanin (kaempferol- 3- O -β-L-arabinopyranoside) [ 47 , 53 ]. A number of researchers have reported that flavonoid glycosides, flavonol glucosides astragalin, quercetrin, isoquercitin, quercetin 3-galactoside, quercetin 3 glucoside, quercetin 3-(6 malonylglucoside) and quercetin 3-(6 malonylgalactoside), quercetin 3- O -galactoside (hyperoside), and catechin were identified from the leaves of C. olitorius [ 49 , 50 , 53 , 56 , 57 ]. The content of quercetin glycosides in C. olitorius leaves was 233 mg/100 g of FW, almost twice that of onion, another significant source of quercetin glycosides [ 52 ].…”

“…Thence, apoptosis in ECO-treated HepG2 cells through caspase-dependent mitochondrial pathway may be induced partially by phytol and mono-galactosyldiacylglycerol [ 14 ]. In the evaluation of nutraceutical properties, polyphenol-enriched extracts (PEEs) of C. olitorius showed cytotoxicity against the colorectal Caco-2 cell line by triggering oxidative stress without disruption of the healthy CCD841 line and inhibition of the activity of glutathione-independent antioxidant enzymes [ 49 ]. Therefore, C. olitorius is suggested as a foodstuff plant with the potential to develop chemopreventive agents for human cancers.…”

“… [ 45 ] C. olitorius Leaf 67% methanol and chloroform Polyphenol-enriched extracts (PEEs) of C. olitorius leaves significantly reduced the viability of tumor Caco-2 cancer cells without any detrimental effects on the healthy CCD841 line. [ 49 ] C. olitorius Leaf Aqueous Significant antiproliferative effects on SUIT-2, A-375 and AGS cells at a concentration as low as 2.54 mg/mL. Moreover, extracts strongly inhibited angiogenesis and the growth of A-375 and AGS tumors.…”

Growth performance and nutritional composition of Clarias gariepinus in flood-and-drain aquaponics coupled with three species of leafy vegetable

“…However, based on careful consideration of the pros and cons of different aquaponic system designs and the limited availability of financial and material resources, this research utilized a media-based design, also known as the flood-and-drain aquaponic system ( Figure 1). The African catfish, Clarias gariepinus , was the preferred fish for the aquaculture unit, while three common vegetables in Nigeria, Celosia argentea, Corchorus olitorius, and Ocimum gratissimum , were the preferred plants for the hydroponic unit based on their food and medicinal values (Guzzetti et al, 2021; Nganteng et al, 2022). This study aimed to compare the growth parameters of C. gariepinus raised in constructed recirculatory aquaponics to those of C. gariepinus raised in conventional fishponds.…”