For thousands of years, mushrooms have long been used for their health promoting
properties. The aim of this study was to determine the fatty acids and amino acids
contents in priority wild mushrooms:
Termitomyces microcarpus
,
Termitomyces
sp.
(Bunyanaka),
Termitomyces globulus
,
Termitomyces eurrhizus
and
Polyporus
tenuiculus
widely consumed in Bunyoro Sub-region, Uganda. The study revealed
seventeen amino acids using pre-column derivatization with a phenylisothiocyanate
followed by HPLC-UV-vis, and tryptophan using spectrophotometry. Fatty acids
were determined by gas chromatography and detected by a flame ion detector. The
essential amino acids ranged from 23.6%
P. tenuiculus to 59.0%
T. microcarpus of
the total amino acids.
Termitomyces sp. (Bunyanaka) and
T. globulus were the most
nutritious species based on essential amino acid indices. Generally, glutamic acid was
high followed by phenylalanine, histidine, tryptophan and lysine concentrations,
whereas threonine, valine, methionine, leucine, cysteine, arginine and tyrosine
contents were either low or absent.
T. eurrhizus and
T. globulus were limited in
leucine and valine,
T. microcarpus in leucine and
Termitomyces sp. (Bunyanaka) in
isoleucine and valine. Unsaturated fatty acids predominated over saturated ones.
Termitomyces sp. (Bunyanaka) and
T. globulus had poor fatty acid profiles, rich in
monounsaturated fatty acids (nervonic and eruic acids), had low PUFA:MUFA ratio
and a PUFA+MUFA:SFA ratio greater than two. Docosahexaenoic (DHA) and a
trans-fatty acid, elaidic were also identified in these mushroom species. This
represents the first report on the occurrence of DHA in mushrooms.
T. microcarpus
had a fairly good profile, high in palmitoleic, λ-linolenic, α- linolenic, palmitic and
oleic acids. Stearic DHA, linoleic and eicosapentaenic acids were detected in small
quantities. The odd carbon number fatty acids (heptadecanoic, heneicosanoic and cis-
10-heptadecanoic) were also identified. These results serve as a basis to encourage the
local communities to exploit the nutritive potentials of these mushrooms in order to
reduce the burden of nutritional deficiencies.