Ethnomycology, sensory analysis and nutritional composition of eight edible mushrooms consumed in the African Great Lakes Region

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Mushrooms of the African Great Lakes Region. Ethnomycology, sensory analysis and nutritional composition

The Great Lakes Region is well known for its astonishing biodiversity, but also for its economic and food shortage. The protein sources are extremely low for local populations [1]. The fungal resources found in the mountain forests play important ecological and economic roles. Studies on mushroom diversity and nutritional values have been carried out in various African countries, including the Miombo woodlands of the D.R. Congo [2] but, until now, knowledge about edible mushrooms of the mountain forests is still fragmentary. The overall objective of the present study is to describe the ecology, the use and to assess the nutritional quality of mushrooms consumed in the Great Lakes Region. Their quality as food is also evaluated through food surveys carried out locally for assessing the interest of their consumption in the local diet. Ethnomycological surveys were conducted with local people to determine which species were most valued. For sensory analysis, the fresh sporophores were cooked, and a nine-point hedonic scale method was used to establish food preferences. The sporophores of six wild edible mushrooms (Termitomyces microcarpus (Berk. & Broome) R. Heim, Termitomyces schimperi (Pat.) R. Heim, Termitomyces robustus (Beeli) R. Heim, Auricularia delicata (Mont. ex Fr.) Henn. Schizophyllum commune Fr. and Hypholoma subviride (Berk. & M.A. Curtis) Dennis) and two cultivated species (Pleurotus ostreatus (Jacq.) P. Kumm. And Agaricus bisporus (J.E. Lange) Imbach), were dried, powdered, and analysed for macronutrients and mineral elements compositions. Data were calculated as % on dry matter basis. The results show that all mushroom samples contained interesting amounts of essential nutrients. The ash, crude protein, total lipids and crude fiber were in the ranges of 3.40-10.85%, 9.38-28.77%, 1.13-2.62% and 10.29-44.99% respectively. Among the eight studied mushrooms, Termitomyces genus contains the highest protein amounts. This specific property coincides with their use to treat children suffering from kwashiorkor as reported by the interviewed local populations. Other mushroom species reported for traditional medicine are S. commune used for enhancing sexual potency in men, and A. delicata used for relieving joint pain. Further analyses on the responsible active compounds are needed for scientific confirmation. The analysed samples also contained appreciable amounts of K, Mg, Fe and Cu. The results of sensory analysis revealed a high appreciation for T. microcarpus, T. schimperi, T. robustus, H. subviride, P. ostreatus and A. bisporus, and a moderate appreciation for A. delicata and S. commune as they scored 8 and 6.98 respectively. References[1] M. Bertomeu Pardo & G. Durán-Romero, 2022 Food security: Agricultural innovation to increase resilience and adaptation to climate change in developing countries, 40 (1)[2] A. De Kesel, & F. Malaisse, 2010, Edible wild food: Fungi. In: F. Malaisse. How to live and survive in Zambezian open forest (Miombo Ecoregion): 41-56. Gembloux, Presses agronomiques.info:eu-repo/semantics/nonPublishe

Stable Nanoparticles Prepared by Heating Electrostatic Complexes of Whey Protein Isolate–Dextran Conjugate and Chondroitin Sulfate

A simple and green method was developed for preparing the stable biopolymer nanoparticles with pH and salt resistance. The method involved the macromolecular crowding Maillard process and heat-induced gelation process. The conjugates of whey protein isolate (WPI) and dextran were produced by Maillard reaction. The nanoparticles were fabricated by heating electrostatic complexes of WPI–dextran conjugate and chondroitin sulfate (ChS) above the denaturation temperature and near the isoelectric point of WPI. Then, the nanoparticles were characterized by spectrophotometry, dynamic laser scattering, zeta potential, transmission electron microscopy, atomic force microscopy, and scanning electron microscopy. Results showed that the nanoparticles were stable in the pH range from 1.0 to 8.0 and in the presence of high salt concentration of 200 mM NaCl. WPI–dextran conjugate, WPI, and ChS were assembled into the nanoparticles with dextran conjugated to WPI/ChS shell and WPI/ChS core. The repulsive steric interactions, from both dextran covalently conjugated to WPI and ChS electrostatically interacted with WPI, were the major formation mechanism of the stable nanoparticles. As a nutrient model, lutein could be effectively encapsulated into the nanoparticles. Additionally, the nanoparticles exhibited a spherical shape and homogeneous size distribution regardless of lutein loading. The results suggested that the stable nanoparticles from proteins and strong polyelectrolyte polysaccharides would be used as a promising target delivery system for hydrophobic nutrients and drugs at physiological pH and salt conditions