Natural Sweeteners and Sweetness-Enhancing Compounds Identified in Citrus Using an Efficient Metabolomics-Based Screening Strategy

Abstract

With the high demand for a healthy diet, it is necessary and important to explore natural sweeteners used in food that enhance palatability but minimize calories. Citrus is considered a good potential source of noncaloric sweeteners, but to date, only one sweetness modulator has been found in this most common fruit crop. Herein, an efficient strategy based on an in-house database and the untargeted and targeted metabolomics analyses was proposed to screen sweeteners or sweet-enhancing compounds from citrus. Eight sweeteners or sweetness-enhancing compounds were screened out, seven of which were newly identified from the genus Citrus. Surprisingly, we identified naturally occurring oxime V, which previously was only known as a synthetic compound. The contents of five compounds, in 11 citrus cultivars or unreleased selections across two production years, were compared. Successful identification of these natural sweeteners and sweetness-enhancing compounds in citrus fruit indicated the potential to identify the relevant biosynthetic pathways and to breed new citrus cultivars containing these compounds that provided both palatability and lower sugar consumption. This study also demonstrated that the proposed metabolomics-based screening strategy could greatly boost the identification of taste modulators with low contents in natural resources.

3D-QSAR studies on the structure–bitterness analysis of citrus flavonoids

“…Eriodictyol and dihydroquercetin which were predicted to have a low bitter taste or no bitter taste, were also sensorially evaluated, and the results obtained showed that eriodictyol and dihydroquercetin had no bitterness at the concentrations of 0.2 mM and 2 mM, respectively. It is worth noting that eriodictyol had been reported as a sweet compound in citrus, 44 which further verified the reliability of the model results. In conclusion, the verified compounds basically agreed with the results of the model and contour plots, which further proved that the experimental results were reliable.…”

Strawberry breeding for improved flavor

“…The characterization of nonvolatile precursors in volatile biosynthetic pathways is also under‐explored and could expand our understanding of how aromas are made and modified. Finally, the discovery of non‐sugar and nonvolatile sweetness enhancers in other fruits such as citrus (Wang et al., 2022) also begs the question of whether such compounds exist in strawberry and how they could be potentially enhanced through breeding.…”

Novel Catechol O-methyltransferases from Lentinula edodes Catalyze the Generation of Taste-Active Flavonoids

“…Interestingly, the aglycone of NHDC, hesperetin dihydrochalcone, and the corresponding flavanone analogue hesperetin along with its regioisomer homoeriodictyol have been reported to possess taste-active properties as well. [12][13][14][15]10 NHDC is a semisynthetic compound, which is commonly produced by hydrogenation of the naturally occurring neohesperidin under alkaline conditions. 7 Through subsequent hydrolysis of the neohesperidose sugar moiety, hesperetin dihydrochalcone can be formed.…”

“…However, some flavanones and dihydrochalcones show remarkable bitter-masking or sweet-tasting properties. − Naringin dihydrochalcone and, especially, neohesperidin dihydrochalcone (NHDC) are well-known taste-active flavonoids widely applied in foods. Interestingly, the aglycone of NHDC, hesperetin dihydrochalcone, and the corresponding flavanone analogue hesperetin along with its regioisomer homoeriodictyol have been reported to possess taste-active properties as well. − , NHDC is a semisynthetic compound, which is commonly produced by hydrogenation of the naturally occurring neohesperidin under alkaline conditions . Through subsequent hydrolysis of the neohesperidose sugar moiety, hesperetin dihydrochalcone can be formed.…”