Microscopic Characteristics, Chromatographic Profiles and Inhibition of Peroxidase Activity of the Leaves of <i>Manihot esculenta</i>and <i>Manihot glaziovii</i>, Consumed as Traditional Vegetables

Methanolic extracts from the leaves of Manihot esculenta (Two cultivars) and Manihot glaziovii, consumed as traditional vegetables in DR. Congo was chemically characterized by Thin layer Chromatography and High Performance Liquid Chromatography. In vitro biochemical activities of extracts against Radical Oxidative Species (ROS) production were assessed in cellular models, on enzymes, Myeloperoxidase (MPO) and Horseradish Peroxidase (HRP) involved in inflammation. The microscopic analysis of the powder of leaves showed that each species displays specific and discriminating botanical microscopic features. Varieties of M. esculenta had a chemical fingerprint different from M. glaziovii. The majority of compounds were polyphenols, represented mainly by rutin, kaempferol-3-O-rutinoside, amentoflavone, phenolic acids such as gallic acid. All extracts exhibited high cellular antioxidant activity in the range of 0.1 to 10 μg·mL-1 using lucigenin with neutrophils, but a moderate cellular antioxidant activity ranging between 10 and 100 μg·mL-1 with DCFDA on HL60 monocytes. Extracts from Manihot leaves showed a pronounced inhibitory effect on the production of extracellular ROS, on HRP and myeloperoxidase activity. Cellular antioxidant activities, the inhibitory effect on HRP of extracts from M. glaziovii, M. esculenta cultivar Mwambu were significantly higher, but their inhibitory effect on the activity of MPO was lower than those of M. esculenta cultivar TEM 419. The biological activities of Manihot esculenta and Manihot glaziovii were well correlated to their phytochemicals that could justify their traditional use as vegetables, potential functional foods or nutraceutical resources and medicines.

Selenium Content and Antioxidant Potential of Some Edible Wild Mushrooms from Bandundu Area, DR Congo

Nutrition is an important aspect of public health because it is linked to many significant diseases and health problems. This work is part of the promotion of traditional foods from the Democratic Republic of Congo in general and in the province of Bandundu, in particular by assessing the selenium content and the antioxidant capacity of wild edible mushrooms. Methanolic extracts from selected mushrooms were characterized for their chemical fingerprint by TLC and their in vitro antioxidant activities using ABTS, DPPH assays. Phytochemical screening revealed the presence of alkaloids, free amines, steroids and terpenes in all species. However, Auricularia delicata and Pleurotus tuberregium contain flavonoids. All extracts displayed a good radical-scavenging activity at the concentration range 1 - 300 μg/mL in the following order: Auricularia delicata > Lentinus cf cladopus > Pleurotus tuberregium > Marasmius buzungolo > Schizophillum commune. Studied mushrooms showed the interest quantity of selenium and L. cf cladodus had the highest concentration. Moderate selenium content of these wild mushrooms associated with their important antioxidant activities could provide health benefits to Bandundu’s populations in protecting against oxidative damage under different conditions including konzo.