Can cornelian cherry mask bitter taste of probiotic chocolate? Human TAS2R receptors and a sensory study with comprehensive characterisation of new functional product

Docking analysis of phenolic acid and flavonoids with selected TAS2R receptors and in vitro experiment

Cornelian cherry fruits contain a wide range of phenolic acids, flavonoids, and other secondary metabolites. Selected flavonoids may inhibit the perceiving of bitterness, however, the full mechanism with all TAS2R bitter taste receptors is not known. The aim of the study was to determine the inhibitory effect of Cornus mas phenolics against the bitterness receptors TAS2R13 and TAS2R3 through functional in vitro assays and coupling studies. The overall effect was validated by analysing the inhibition of the receptors activity in cells treated with tested cornelian cherry extracts. The strength of interaction with both TAS2R receptors varied between studied compounds with different binding affinity. Most compounds bonded with the TAS2R3 receptor through a long-distant hydrophobic interaction with Trp89A and π-π orbital overlapping-between phenolic and tryptophane aromatic rings. For TAS2R13 observed were various mechanisms of interaction with the compounds. Nonetheless, naringin and quercetin had most similar binding affinity to chloroquine and denatonium-the model agonists for the receptor.

How Does In Vitro Digestion Change the Amount of Phenolics in Morus alba L. Leaf? Analysis of Preparations and Infusions

The application of Morus alba L. in traditional oriental medicine and cuisine has resulted in numerous studies on its health-promoting effects. However, if the process is not monitored by the manufacturers, the processing of the leaves alters the obtained health-promoting properties and results in different health qualities in the final composition of dietary supplements. This article aims to analyze changes (using the HPLC/DAD method) in the proposed conditioned mulberry leaves in terms of key compounds (phenolic acids and flavonols) responsible for antioxidant activity after being digested in in vitro conditions. The analyzed material was leaves of white mulberry (Morus alba L.) cv. Żółwińska wielkolistna, conditioned (1-4 h) and non-conditioned. The conditioning process of mulberry proposed here, e.g., for industry production, resulted in variable transformations of polyphenols during in vitro digestion. For many polyphenols, especially those shown in the highest amounts, significant correlations were found between their content and conditioning, as well as the stage of digestion. In the case of mulberry infusions, the amounts of individual polyphenols were several times lower than in the preparations, which was due to the degree of dilution. Their amounts tended to decrease in the course of digestion. Taking this into account, it seems justified to continue research on the in vivo bioavailability of bioactive components from conditioned Morus alba L. leaves.

Morus alba L. Leaves (WML) Modulate Sweet (TAS1R) and Bitter (TAS2R) Taste in the Studies on Human Receptors - A New Perspective on the Utilization of White Mulberry Leaves in Food Production?

From the nutritional perspective, the main direction of the utilization of white mulberry (Morus alba L.) parts so far has been to produce dietary supplements or functional foods for individuals with diabetes or over-weight. Its leaves are widely known as a valuable source of bioactive compounds responsible for its antioxidant and antidiabetic effects, both in animals and humans. The authors found that processed leaves can also be investigated as potential bitter and/or sweet taste modulators-an important property of new functional foods. The study aimed to validate the inhibitory effect of Morus alba L. on the TAS2R3 and TAS2R13 bitter taste and TSA1R2/TSA1R3 receptors and determine the changes that the conditioning process caused in such receptors. The effect on the receptors was evaluated in specially transfected HEK293T cells, and the inhibition ratio was measured using the calcium release test. Moreover, the stability of phenolics in the simulated intestinal in vitro digestion process was determined. Results showed that the Morus alba leaf extracts were rich in gallic, chlorogenic and caffeic acids together with rutin and quercetin 3-(6-malonyl)-glucoside, while the conditioning process positively affected their amount. Most identified phenolics were reduced during in vitro digestion. In the taste receptors test, it was found that the phytochemicals from conditioned Morus alba leaf extract enhanced sweet taste, together with a reduction of bitter taste receptor activity in some cases. To conclude, the study has found that Morus alba, especially when conditioned for 4 h, seems to be a valuable modulator of taste, which should be considered in future research as a crucial reason for its new utilization.

Cornelian Cherry (Cornus mas) Powder as a Functional Ingredient for the Formulation of Bread Loaves: Physical Properties, Nutritional Value, Phytochemical Composition, and Sensory Attributes

In the current study, Cornelian cherry powder (CCP, Cornus mas) was investigated as a functional ingredient for bread production. Experimental bread loaves were prepared using five levels of CCP (0, 1, 2, 5, and 10% w/w) to replace wheat flour in bread formulation. The final products were analyzed regarding their proximate composition, content of selected biologically active substances, antioxidant activity (AA), volume, and sensory attributes. Increasing the incorporation of CCP led to significantly (p < 0.05) higher concentrations of carbohydrate, ash, energetic value, total polyphenols, phenolic acids and AA, and reduced fat and protein contents (p < 0.05). Moreover, up to 5% addition of CCP positively affected the volume (642.63 ± 7.24 mL) and specific volume (2.83 ± 0.02 cm³/g) of bread loaves, which were significantly (p < 0.05) higher compared to the control (no addition of CCP; 576.99 ± 2.97 mL; 2.55 ± 0.002 cm³/g). The sensory attributes chewiness, crumb springiness, bitterness, and sourness had lower scores (p < 0.05) in bread formulated with 10% CCP compared to the control. Overall, results show that the bread loaves produced with up to 5% CCP addition were considered the preferred formulation among the experimental samples tested, taking into consideration their composition, bioactive content, sensory, and physical properties.