Impact of Lactic Acid Bacteria Fermentation on (Poly)Phenolic Profile and In Vitro Antioxidant and Anti-Inflammatory Properties of Herbal Infusions.

Recently, the development of functional beverages has been enhanced to promote health and nutritional well-being. Thus, the fermentation of plant foods with lactic acid bacteria can enhance their antioxidant capacity and others like anti-inflammatory activity, which may depend on the variations in the total content and profile of (poly)phenols. The present study aimed to investigate the impact of fermentation with two strains of Lactiplantibacillus plantarum of several herbal infusions from thyme, rosemary, echinacea, and pomegranate peel on the (poly)phenolic composition and whether lacto-fermentation can contribute to enhance their in vitro antioxidant and anti-inflammatory effects on human colon myofibroblast CCD18-Co cells. HPLC-MS/MS analyses revealed that fermentation increased the content of the phenolics present in all herbal infusions. In vitro analyses indicated that pomegranate infusion showed higher antioxidant and anti-inflammatory effects, followed by thyme, echinacea, and rosemary, based on the total phenolic content. After fermentation, despite increasing the content of phenolics, the antioxidant and anti-inflammatory effects via reduction pro-inflammatory markers (IL-6, IL-8 and PGE2) were similar to those of their corresponding non-fermented infusions, with the exception of a greater reduction in lacto-fermented thyme. Overall, the findings suggest that the consumption of lacto-fermented herbal infusions could be beneficial in alleviating intestinal inflammatory disorders.

Polyphenolic Characterization and Anti-Inflammatory Effect of In Vitro Digested Extracts of Echinacea purpurea L. Plant Parts in an Inflammatory Model of Human Colon Cells.

Echinacea purpurea L. (EP) preparations are globally popular herbal supplements known for their medicinal benefits, including anti-inflammatory activities, partly related to their phenolic composition. However, regarding their use for the management of inflammation-related intestinal diseases, the knowledge about the fate of orally ingested constituents throughout the human gastrointestinal tract and the exposition of in vitro digested extracts in relevant inflammatory models are unknown. This study investigated for the first time the impact of in vitro gastrointestinal digestion (INFOGEST) on the phenolic composition and anti-inflammatory properties of EP extracts from flowers (EF), leaves (EL), and roots (ER) on IL-1ß-treated human colon-derived CCD-18Co cells. Among the seven hydroxycinnamic acids identified using HPLC-UV-MS/MS, chicoric and caftaric acids showed the highest concentrations in EL, followed by EF and ER, and all extracts exerted significant reductions in IL-6, IL-8, and PGE2 levels. After digestion, despite reducing the bioaccessibility of their phenolics, the anti-inflammatory effects were preserved for digested EL and, to a lesser extent, for EF, but not for digested ER. The lower phenolic content in digested EF and ER could explain these findings. Overall, this study emphasizes the potential of EP in alleviating intestinal inflammatory conditions and related disorders.

Chewable tablet with herbal extracts and propolis arrests Wuhan and Omicron variants of SARS-CoV-2 virus.

Prevention of COVID-19 is of paramount importance for public health. Some natural extracts might have the potential to suppress COVID-19 infection. Therefore, this study aimed to design a standardised, efficient, and safe chewable tablet formulation (with propolis and three herbal extracts) for possible prevention against two variants (Wuhan B.1.36 and Omicron BA.1.1) of SARS-CoV-2 virus and other viral infections. Green tea, bilberry, dried pomegranate peel, and propolis extracts were selected for this purpose. Cytotoxicity and antiviral activity of each component, as well as the developed chewable tablet, were examined against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) virus using Vero E6 cells with the xCELLigence real-time cell analyser-multiple plates system. Anti-inflammatory and analgesic activities, as well as mutagenicity and anti-mutagenicity of the chewable tablet were also analysed. Compared to the control, it was observed that the chewable tablet at concentrations of 110 and 55 µg/mL had antiviral activity rates of 101% and 81%, respectively, for the Wuhan variant and 112% and 35%, respectively, for the Omicron variant. The combination of herbal extracts with propolis extract were synergically more effective (∼7-fold higher) than that of individual extract. The present work suggests that a combination of herbal extracts with propolis at suitable concentrations can effectively be used as a food supplement for the prevention of both variants of the SARS-CoV-2 virus in the oral cavity (the first entry point of the SARS-CoV-2 virus).

Development of propolis and essential oils containing oral/throat spray formulation against SARS-CoV-2 infection.

A broad range of evidence has confirmed that natural products and essential oils might have the potential to suppress COVID-19 infection. Therefore, this study aimed to develop an oral/throat spray formulation for prophylactic use in the oral cavity or help treatment modalities. Based on a reference survey, several essential oils, a cold-pressed oil, and propolis were selected, and cytotoxicity and antiviral activity of each component and the developed spray formulation were examined against severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) infection using Vero E6 cells. Anti-inflammatory, antimicrobial, and analgesic activities as well as mutagenicity and anti-mutagenicity of the formulation were analysed. Forty-three phenolics were identified in both propolis extract and oral/throat spray. The spray with 1:640-fold dilution provided the highest efficacy and the cytopathic effect was delayed for 54 h at this dilution, and the antiviral activity rate was 85.3%. A combination of natural products with essential oils at the right concentrations can be used as a supplement for the prevention of SARS-CoV-2 infection.

Phenolic profiles and antioxidant activity of Turkish Tombul hazelnut samples (natural, roasted, and roasted hazelnut skin).

The phenolic profiles and antioxidant status of hazelnut samples [natural (raw) hazelnut, roasted hazelnut, and roasted hazelnut skin] were compared. Free and bound (ester-linked and glycoside-linked) phenolic acids were examined using liquid chromatography-tandem mass spectrometry (LC-MS/MS). Comprehensive identification of phenolics was carried out using Q-exactive hybrid quadrupole-orbitrap mass spectrometer (Q-OT-MS). Samples were also assessed for their total phenolics and antioxidant activities using three different assays. Ten free and bound phenolic acids were quantified in hazelnut samples. Roasted hazelnut skin contained the highest content of total phenolic acids, followed by natural and roasted hazelnuts. The majority of phenolic acids were present in the bound form. Using a Q-OT-MS, 22 compounds were tentatively identified, 16 of which were identified for the first time in hazelnut samples. The newly identified compounds consisted of flavonoids, phenolic acids and related compounds, hydrolysable tannins and related compounds, and other phenolics. Three antioxidant assays demonstrated similar trends that roasted hazelnut skin rendered the highest activity. The present work suggests that roasted hazelnut skin is a rich source of phenolics and can be considered as a value-added co-product for use as functional food ingredient and antioxidant.

Volatile compounds and sensory characteristics of various instant teas produced from black tea.

Various instant teas produced differently from black tea [freeze-dried instant tea (FDIT), spray-dried instant tea (SDIT), and decaffeinated instant tea (DCIT)], were compared for their differences in volatile compounds as well as descriptive sensory analysis (DSA). A total of 63 volatile compounds in all tea samples (eight aldehydes, ten alcohols, nine ketones, five esters, eight acids, ten terpenes/terpenoids, ten furans/furanones, two pyrroles, and one miscellaneous compound) were tentatively identified. Black tea, FDIT, SDIT, and DCIT contained 60, 55, 47, and 40 volatile compounds, respectively. Ten flavour attributes such as after taste, astringency, bitter, caramel-like, floral/sweet, green/grassy, hay-like, malty, roasty, and seaweed were identified. Intensities for a number of flavour attributes (except for caramel-like in SDIT and bitter and after taste in DCIT) were not significantly different (p>0.05) among tea samples. The present study suggests that instant teas can also be used as good alternative to black tea.

Validated Method for the Characterization and Quantification of Extractable and Nonextractable Ellagitannins after Acid Hydrolysis in Pomegranate Fruits, Juices, and Extracts.

Pomegranates are one of the main highly valuable sources of ellagitannins. Despite the potential health benefits of these compounds, reliable data on their content in pomegranates and derived extracts and food products is lacking, as it is usually underestimated due to their complexity, diversity, and lack of commercially available standards. This study describes a new method for the analysis of the extractable and nonextractable ellagitannins based on the quantification of the acid hydrolysis products that include ellagic acid, gallic acid, sanguisorbic acid dilactone, valoneic acid dilactone, and gallagic acid dilactone in pomegranate samples. The study also shows the occurrence of ellagitannin C-glycosides in pomegranates. The method was optimized using a pomegranate peel extract. To quantify nonextractable ellagitannins, freeze-dried pomegranate fruit samples were directly hydrolyzed with 4 M HCl in water at 90 °C for 24 h followed by extraction of the pellet with dimethyl sulfoxide/methanol (50:50, v/v). The method was validated and reproducibility was assessed by means of an interlaboratory trial, showing high reproducibility across six laboratories with relative standard deviations below 15%. Their applicability was demonstrated in several pomegranate extracts, different parts of pomegranate fruit (husk, peels, and mesocarp), and commercial juices. A large variability has been found in the ellagitannin content (150-750 mg of hydrolysis products/g) and type (gallagic acid/ellagic acid ratios between 4 and 0.15) of the 11 pomegranate extracts studied.

Compositional, nutritional, and functional characteristics of instant teas produced from low- and high-quality black teas.

Two types of instant teas produced from low- and high-quality black teas were examined for their proximate composition, dietary fiber, minerals, water-soluble vitamins, total phenolic content, various antioxidant assays, phenolics (flavanols, condensed phenolics, and phenolic acids), alkaloids, and carotenoids as well as taste-active compounds (sugars, organic acids, and free amino acids). Some variations, albeit to different extents, were observed (p < 0.05) among these parameters between instant teas produced from low- and high-quality black teas. With respect to proximate composition, carbohydrate was the predominant component (56.68-59.84 g/100 g), followed by protein (19.31-19.86 g/100 g). Ash, moisture, and, to a lesser extent, dietary fiber and fat were also present in both instant teas. Thirteen minerals, four water-soluble vitamins, six flavanols, two alkaloids, three condensed phenolics, one phenolic acid, and one carotenoid were identified. Total phenolic content varied between 17.35 and 17.82 g of gallic acid equivalents (GAE)/100 g instant tea. With regard to antioxidant activities, three different assays such as oxygen radical absorbance capacity (ORAC), trolox equivalent antioxidant capacity (TEAC), and cupric ion reducing antioxidant capacity (CUPRAC) were measured. No significant differences (p > 0.05) in total phenolic, ORAC, TEAC, and CUPRAC contents between low- and high-quality instant teas were observed. With regard to taste-active compounds, 3 sugars, 5 organic acids, and 18 free amino acids were positively identified, of which fructose, tannic acid, and theanine predominated, respectively. The present work suggests that despite some differences, instant teas produced from low- and high-quality black teas should not be distinguished on the basis of their compositional, nutritional, and functional characteristics as well as taste-active compounds.

Effects of a traditional fermented grape-based drink 'hardaliye' on antioxidant status of healthy adults: a randomized controlled clinical trial.

BACKGROUND: The antioxidative effects of the traditional grape-based beverage, hardaliye, were investigated with a 40-day randomized controlled clinical trial on 89 healthy adults. Subjects were randomly divided into three groups: high hardaliye (HH), low hardaliye (LH) and control group. HH and LH groups consumed 500 mL and 250 mL hardaliye per day, respectively, and the control group did not consume any hardaliye. Dien conjugate (DC), malondialdehyde (MDA), vitamin C, total antioxidant capacity (TAC) and homocysteine concentrations were measured in fasting blood samples collected at baseline and after intervention. RESULTS: Significant decreases in DC, MDA and homocysteine concentrations were observed in HH and LH groups (P < 0.001) after intervention, whereas the control group showed no change. The reduction in homocysteine was significantly different between HH and LH groups (P < 0.001), except for DC and MDA. TAC and vitamin C were slightly increased; however, the change was not statistically significant. CONCLUSION: Dietary supplementation with hardaliye affect the MDA, DC and homocysteine levels in blood, possibly due to the presence of antioxidant compounds. Dose response was only observed for homocysteine. Further studies need to be performed to assess the effects on antioxidant capacity.

Nutritional and functional characteristics of seven grades of black tea produced in Turkey.

Seven grades of black tea [high-quality black tea (grades 1-3) and low-quality black tea (grades 4-7)], processed by ÇAYKUR Tea Processing Plant (Rize, Turkey), were examined for their proximate composition, dietary fiber, minerals, and water-soluble vitamins as well as total phenolic content, various antioxidant assays, phenolics (flavanols, alkoloids, condensed phenolics, and phenolic acids), chlorophylls, and carotenoids. Some variations, albeit to different extents, were observed (p < 0.05) among these parameters in seven grades of black tea. With respect to proximate composition, dietary fiber was the predominant compound (ranging from 49.68 to 54.31 g/100 g), followed by protein, carbohydrate, and, to a lesser extent, ash, moisture, and fat. Thirteen minerals, four water-soluble vitamins, six flavanols, two alkoloids, three condensed phenolics, one phenolic acid, two chlorophylls, and two carotenoids were identified in the seven grades of black tea. Total phenol content ranged from 7.52 to 8.29 g of gallic acid equivalents (GAE)/100 g, being lowest in grade 6 and highest in grade 1. With regard to antioxidant activities, a large variation in oxygen radical absorbance capacity (ORAC) values was observed among all grades of black tea (ranging from 777 µmol of trolox equivalents (TE)/g in grade 7 to 1210 µmol of TE/g in grade 3). The present work suggests that high- and low-quality black teas should not be distinguished on the basis of their nutritional and functional characteristics. The combination of nutritional compounds together with functional characteristics renders combination effects that provide the characteristic quality of each grade of black tea.

Flavor characteristics of seven grades of black tea produced in Turkey.

Seven grades of black tea [high-quality black tea (grades 1-3) and low-quality black tea (grades 4-7)], processed by ÇAYKUR Tea Processing Plant (Rize, Turkey), were compared for their differences in descriptive sensory analysis (DSA), aroma-active compounds (volatile compounds), and taste-active compounds (sugar, organic acid, and free amino acid compositions). Ten flavor attributes such as 'after taste', 'astringency', 'bitter', 'caramel-like', 'floral/sweet', 'green/grassy', 'hay-like', 'malty', 'roasty', and 'seaweed' were identified. Intensities for a number of flavor attributes ('after taste', 'caramel-like', 'malty', and 'seaweed') were not significantly different (p > 0.05) among seven grades of black tea. A total of 57 compounds in seven grades of black tea (14 aldehydes, eight alcohols, eight ketones, two esters, four aromatic hydrocarbons, five aliphatic hydrocarbons, nine terpenes, two pyrazines, one furan, two acids, and two miscellaneous compounds) were tentatively identified. Of these, aldeyhdes comprised more than 50% to the total volatile compounds identified. In general, high-grade quality tea had more volatiles than low-grade quality tea. With respect to taste-active compounds, five sugars, six organic acids, and 18 free amino acids were positively identified in seven grades of black tea, of which fructose, tannic acid, and theanine predominated, respectively. Some variations (p < 0.05), albeit to different extents, were observed among volatile compounds, sugars, organic acids, and free amino acids in seven grades of black tea. The present study suggests that a certain flavor attributes correlate well with taste- and aroma-active compounds. High- and low-quality black teas should not be distinguished solely on the basis of their DSA and taste- and aroma-active compounds. The combination of taste-active compounds together with aroma-active compounds renders combination effects that provide the characteristic flavor of each grade of black tea.

Effects of roasting on the antioxidant status and phenolic profiles of commercial Turkish hazelnut varieties (Corylus avellana L.).

The effect of roasting on the antioxidant status and phenolic profiles of seven commercial Turkish hazelnut varieties (namely, Çakildak, Fosa, Karafindik, Mincane, Palaz, Sivri, and Tombul) was assessed. Samples were examined for their total phenolics, oxygen radical absorbance capacity (ORAC) values, condensed tannins, and phenolic acids (free and bound forms). Significant losses (p < 0.05) in total phenolics (~66.3%), ORAC values (~41.6%), condensed tannins (~75.2), and phenolic acids (~42.7) were noted when the hazelnuts were roasted. Some variations both between and within natural and roasted hazelnuts were observed (p < 0.05). Phenolic acids were mainly found in the bound form. Gallic, protocatechuic, p-coumaric, and ferulic + sinapic acids were present in all hazelnut varieties, albeit to different extents, and the first two were dominant. Mincane, in roasted form, had the highest total phenolics, ORAC values, condensed tannins, and phenolic acids. This was due to the presence of some skin in roasted Mincane. No skin was left in all other varieties upon roasting. The present work suggests that roasting results in a significant loss in the antioxidant status and phenolic profiles because of the removal of the skin, which is a rich source of phenolics. It is highly recommended to consume natural hazelnut instead of the roasted counterpart to take advantage of all of the functional benefits of this nut.

Effects of roasting on taste-active compounds of Turkish hazelnut varieties ( Corylus avellana L.).

The effect of roasting on taste-active components of 18 native hazelnut varieties, grown in the Giresun province of Turkey, was assessed. Samples were examined for their sugars, organic acids, condensed tannins, and free phenolic acids. Six sugars (fructose, glucose, sucrose, myo-inositol, raffinose, and stachyose), seven organic acids (oxalic, maleic, citric, malic, lactic, succinic, and acetic), and one phenolic acid (gallic acid) were positively identified in natural and roasted hazelnut varieties; among these, sucrose, malic acid, and gallic acid predominated, respectively. Total sugars among hazelnut varieties ranged from 1.99 to 4.94 g/100 g, organic acids from 0.96 to 2.72 g/100 g, condensed tannins from 3.99 to 40.56 mg of catechin equivalents/g, and gallic acid from 0.159 to 0.871 mg/100 g. Differences existed in the sugar and organic acid contents between natural and roasted hazelnut varieties, but they did not follow any particular trend. Significant losses (p < 0.05) in condensed tannins ( approximately 97.3%) and gallic acid ( approximately 66.7%) were noted when the hazelnuts were roasted. The present work suggests that roasting resulted in significant loss in condensed tannins and gallic acid due to the removal of the brown skin. The effect of roasting on sugars and organic acids was not noteworthy.

Effects of roasting on oil and fatty acid composition of Turkish hazelnut varieties (Corylus avellana L.).

A total of 18 natural and roasted hazelnut varieties (namely, Aci, Cavcava, Cakildak, Fosa, Ham, Incekara, Kalinkara, Kan, Karafindik, Kargalak, Kus, Mincane, Palaz, Sivri, Tombul, Uzunmusa, Yassi Badem, and Yuvarlak Badem), grown in the Giresun province of Turkey, were compared for their differences in oil content and fatty acid profiles. The oil content in natural and roasted hazelnut varieties ranged from 57.85% for Kargalak to 68.31% for Incekara and from 61.37% for Kargalak to 71.72% for Incekara, respectively. A total of 20 fatty acids were identified in oils extracted from different varieties of natural and roasted hazelnuts. Among the identified fatty acids in natural hazelnut oils, 18:1omega9 was the dominant fatty acid (ranging from 77.77 to 86.91%). Roasting had minor influence on the fatty acid profiles. These results suggest that semi-commercial hazelnut varieties are as good source of oils and possess valuable fatty acid profiles as commercial varieties (Tombul, Cakildak, Fosa, Karafindik, Mincane, Palaz, and Sivri).