Effects of different medical masks on acoustic and aerodynamic voice assessment during the COVID-19 pandemic.

The purpose of the study was to investigate the effect of the surgical masks and N95 masks on the acoustic and aerodynamic parameters of voice assessment during the coronavirus disease 2019 pandemic. The challenge of the study was to enable each inexperienced participant to perform a number of acoustic and aerodynamic voice assessment in a qualified and homogeneous manner without and with medical masks, and to minimize the individual differences. There were 32 healthy participants recruited in the study, including 16 males and 16 females. The acoustic parameters analyzed included fundamental frequency, standard deviation of fundamental frequency (fundamental frequency standard deviation), percentage of jitter (%), percentage of shimmer (%), glottal-to-noise excitation ratio (GNE), and the parameters of irregularity, noise and overall severity. The aerodynamic parameters included s time, z time, s/z ratio and maximum phonation time. When wearing surgical masks, the GNE ratio (P = .043) significantly increased, whereas noise (P = .039) and s time (P = .018) significantly decreased. When wearing N95 masks, the percentage of shimmer (P = .049), s time (P = .037) and s/z ratio (P = .048) significantly decrease. In general, performing voice assessment with a medical mask proved to be reliable for most of the acoustic and aerodynamic parameters. It is worth noting that the shimmer (%), could be slightly impacted when wearing N95 masks. Wearing surgical masks might slightly influence the measurement of noise and higher GNE ratio. The s/z ratio could be affected when wearing N95 masks. The contribution of the study is to explore acoustic and aerodynamic parameters that might be easily affected by wearing masks during the voice assessment, and provide references for clinical evaluation of voice disorders during the pandemic of coronavirus disease 2019.

Antioxidant activity and effective compounds of immature calamondin peel.

The antioxidant activity and the flavonoids of mature and immature calamondin (Citrus mitis Blanco) peel were investigated. The hot water extract of immature calamondin peel exhibited the highest oxygen radical absorbance capacity (ORAC), reducing power, and superoxide scavenging effect. 3',5'-Di-C-ß-glucopyranosylphloretin, naringin, hesperidin, nobiletin, and tangeretin are the five major flavonoids found in hot water extract with the levels of 6888±522, 2333±157, 1350±94, 165±13, and 8±4 mg/100 g dry basis, respectively. The contents of nobiletin and tangeretin increased after ripening. The hot water extract of immature calamondin peel was fractionated using a semi-preparative HPLC. Fraction VI showed the highest ORAC value (28.02±2.73 mmol Trolox equivalents (TE)/g fraction) and two compounds, naringin and hesperidin, were identified as the major active components attributed to the antioxidant activity. Fraction V contained 3',5'-di-C-ß-glucopyranosylphloretin, which revealed low ORAC value with 7.43 mmol TE/g fraction. However, it might also contribute to antioxidant activity in immature calamondin peel due to its greatest quantity.

Tyrosinase inhibitory components of immature calamondin peel.

There is broad range of applications in the use of tyrosinase inhibitors for suppressing unwanted hyperpigmentation in human skin and enzymic browning in fruits. In searching effective tyrosinase inhibitors from natural products, the components in unripe calamondin (Citrus mitis Blanco) peel were investigated by performing bioassay-directed fractionation and chromatographic separation coupled with tyrosinase inhibition assay. Herein it is reported for the first time that (1) there is a rich content of 3',5'-di-C-ß-glucopyranosylphloretin in unripe calamondin peel, 3.69±0.44g/100g dry basis, (2) this C-glycosylated flavonoid showed the strongest inhibitory activity against tyrosinase among the components in this fruit, with an IC(50) of 0.87mg/ml, and (3) that unripe calamondin peel is also a rich source of naringin and hesperidin, 1.25% and 0.73% by dry weight, respectively, which also expressed strong tyrosinase inhibitory property.

Enhancement of the encapsulation and transmembrane permeation of isoflavone-containing red clover extracts in phospholipid-based microemulsions using different extraction processes.

Several isoflavone-enriched red clover extracts (RCE) prepared by using solid- or liquid-phase extraction or a combination of both were studied for their encapsulation into a phospholipid-based microemulsion system. The optimization process with regard to the bioactive ingredient-encapsulated amounts and transmembrane efficiency of various RCE micelles was demonstrated. The results indicated that the encapsulated amounts of isoflavones in RCE-encapsulated microemulsions (ME) of ME-RC5, ME-RC6, and ME-RC7 were increased by >10-fold when compared with that of the raw red clover extracts. Comparison of the permeability coefficient K(p) of the formononetin among the ME-RCs from the in vitro skin permeation study showed that ME-RC5 significantly exhibited the least permeability, whereas ME-RC6 exhibited enhanced permeability after two-stage solid-phase extraction, indicating the potential role of the matrix material as a barrier or enhancer in the transmembrane study.