Flavanone

About: Flavanone is a research topic. Over the lifetime, 1965 publications have been published within this topic receiving 54729 citations. The topic is also known as: flavanones.

Encapsulation and micronization effectively improve orange beverage flavanone bioavailability in humans.

Abstract: The effect of hesperidin encapsulation and particle size reduction on hesperetin bioavailability was assessed after the intake of orange flavanone beverages. Hesperidin micronization (5.1 μm) increased flavanone's bioavailability 2-fold compared to conventional hesperidin (32.8 μm). Gum Arabic encapsulated hesperidin, with enhanced dispersion in water, also showed increased bioavailability despite having a higher particle size than conventional hesperidin (74.2 μm), showing that flavanone dispersion also enhances its bioavailability. The bioavailability of micronized hesperetin was also evaluated to overcome the need for gut microbiota rhamnosidase hydrolysis. When volunteers were stratified for their flavanone excretion capability, differences among treatments were better observed. The treatments used to increase solubility and decrease particle size to facilitate the interaction with intestinal cells and gut microbiota enhanced bioavailabilty especially in high (9.2 ± 1.5 mg) and medium (5.5 ± 0.3 mg) flavanone excretors. On the contrary, micronized hesperetin bioavailability was particularly high in the case of low excretors (4.3 ± 0.6 mg), showing that the low excretion in these volunteers should be associated with the lack of the appropriate microbiota to release hesperetin from hesperidin. Not all of the low excretors, however, reached the excretion levels of high excretors when hesperetin was supplied, suggesting that differences in intestinal transporters of the volunteers could also affect the flavanone excretion rates observed.

Indirect and direct routes to C-glycosylated flavones in Saccharomyces cerevisiae

Abstract: C-glycosylated flavones have recently attracted increased attention due to their possible benefits in human health. These biologically active compounds are part of the human diet, and the C-linkage makes them more resistant to hydrolysis and degradation than O-glycosides. In contrast to O-glycosyltransferases, few C-glycosyltransferases (CGTs) have so far been characterized. Two different biosynthetic routes for C-glycosylated flavones have been identified in plants. Depending on the type of C-glycosyltransferase, flavones can be glycosylated either directly or indirectly via C-glycosylation of a 2-hydroxyflavanone intermediate formed by a flavanone 2-hydroxylase (F2H). In this study, we reconstructed the pathways in the yeast Saccharomyces cerevisiae, to produce some relevant CGT substrates, either the flavanones naringenin and eriodictyol or the flavones apigenin and luteolin. We then demonstrated two-step indirect glycosylation using combinations of F2H and CGT, to convert 2-hydroxyflavanone intermediates into the 6C-glucoside flavones isovitexin and isoorientin, and the 8C-glucoside flavones vitexin and orientin. Furthermore, we established direct glycosylation of flavones using the recently identified GtUF6CGT1 from Gentiana triflora. The ratio between 6C and 8C glycosylation depended on the CGT used. The indirect route resulted in mixtures, similar to what has been reported for in vitro experiments. In this case, hydroxylation at the flavonoid 3′-position shifted the ratio towards the 8C-glucosylated orientin. The direct flavone glycosylation by GtUF6CGT1, on the other hand, resulted exclusively in 6C-glucosides. The current study features yeast as a promising host for production of flavone C-glycosides, and it provides a set of tools and strains for identifying and studying CGTs and their mechanisms of C-glycosylation.

Antibacterial activity of flavanone isolated from Sophora exigua against methicillin‐resistant Staphylococcus aureus and its combination with antibiotics

Abstract: 5,7,2',4'-Tetrahydroxy-8-lavandulyl-flavanone, isolated from Sophora exigua, completely inhibited the growth of 21 strains of methicillin-resistant Staphylococcus aureus (MRSA) at concentrations of 3.13-6.25 μg/mL. The anti-MRSA effect was based on bactericidal action. In combinations of the flavanone with vancomycin, minocycline and rifampicin, the fractional inhibitory concentration indices were 0.90, 0.88 and 0.85, respectively, indicating partial synergistic effects with anti-MRSA antibiotics. The proposed flavanone would be a potent phytotherapeutic agent against MRSA infections.

A new flavanone and other flavonoids from green perilla leaf extract inhibit nitric oxide production in interleukin 1β-treated hepatocytes

Abstract: A new flavanone, shisoflavanone A (1), and several flavonoids were purified from the ethyl acetate-soluble fraction of green perilla leaves (Perilla frutescens Britton var. crispa form viridis), and their structures were identified. Shisoflavanone A was elucidated as 8-hydroxy-6,7-dimethoxyflavanone based on its spectral data. Other constituents of the ethyl acetate-soluble fraction, i.e. 5,8-dihydroxy-7-methoxyflavanone (2), negletein (5,6-dihydroxy-7-methoxyflavone) (3), luteolin (4), apigenin (5), esculetin (6), and protocatechuic acid (7), were identified. This is the first time that constituents 2, 3, and 6 have been found in green perilla. Shisoflavanone A and the other constituents (except 7) significantly inhibited nitric oxide production in interleukin 1β-stimulated rat hepatocytes, which have been used to monitor the anti-inflammatory effects of herbal constituents. The present findings suggest that these constituents, including shisoflavanone A, may be involved in the anti-inflammatory effects of green perilla leaves.