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Desert truffles are popular ectomycorrhizal fungi valued worldwide for their nutritional and traditional health benefits. Herein, two chief desert truffles viz., Terfezia claveryi and T. boudieri were assessed for their metabolites heterogeneity in context of their volatile sensory and nutrients profile as analyzed via GC-MS. Primary metabolites accounting for nutritive indices in T. claveryi and T. boudieri were investigated with 61 peaks belonging to sugars, sugar alcohols and amino acids. After headspace solid-phase microextraction (HS-SPME), a total of 106 volatiles were annotated belonging to alcohols, ketones, aldehydes, esters, ethers and furans. The abundance of oxygenated monoterpenes as antimicrobials rationalizes for the folk use of desert truffles against trachoma. Benzyl isothiocyanate was detected as the sulfur containing volatile component in desert truffle and absent from truffles. Multivariate data analyses (MVA) revealed that 1-octen-3-ol and 3-octanone were the most significantly contributors in the discrimination of T. claveryi and T. boudieri specimens. Being more enriched in essential amino acids, T. claveryi provided a better sugar diet composition concurrent with lower sugars and higher sugar alcohols compared to T. boudieri. This study provides the first insight into desert truffles metabolites and sensory composition, and to account for its culinary and medicinal uses.

Mahlab cherry (Prunus mahaleb L.) is a plant native to the Mediterranean basin and Eastern Europe, with several health benefits and culinary uses. We explored the compositional heterogeneity in the aroma profile and nutrients of three P. mahaleb seeds in the context of its cultivar type, i.e., white and red, and in response to roasting. A holistic untargeted metabolomics approach was employed for the first time using solid-phase microextraction (SPME–GC–MS) profiles of seed volatiles and primary metabolites coupled with chemometrics. Around 65 peaks belonging to sugars, fatty acids, esters and organic acids were identified by GC–MS. White mahlab from Egypt is rich in fatty acids, e.g., oleic and α-linolenic acids. Some acyl esters, e.g., glycerylmonostearate and n-butylcaprylate, characterized mahlab cultivars from various origins. A total of 135 volatiles were identified, with organic acids and aldehydes the most abundant. Aldehydes were the most discriminatory in seed origin and in accounting for its distinct aroma. Several roasting indices were identified, viz. 1-octanol, γ-caprolactone and isomintlactone. A direct relationship between furans and fatty acids was rationalized by cyclic transformation of the latter into furan derivatives. This study provides the first chemical evidence supporting the nutritional and flavor determinants of mahlab seeds, suggesting novel uses as a functional food.