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The purpose of this paper is to evaluate the effect of green tea polyphenols addition on physicochemical, microbiological and bioactive characteristics of yogurt.

Two incorporation methods of polyphenols were evaluated: direct addition or incorporated within protein particles of whey protein concentrate and gelatin. During yogurt’s shelf life, structure characteristics (water holding capacity, textural and rheological parameters), lactic acid bacteria (LAB) viability and polyphenols antioxidant activity were analyzed. Also, polyphenol bioaccesibility after in vitro digestion was evaluated.

Polyphenols addition (by the two methods used) did not affect the dynamics of the fermentation process, nor the LAB viability during storage. The color parameter a* for the yogurts with the highest polyphenol concentrations showed positive values (tending to red), but not visible to the naked eye. Because of the ability of polyphenols to interact with milk proteins, yogurts with polyphenols presented higher values in firmness and cohesiveness with respect to the control. Additionally, the incorporation of polyphenols in protein particles increased even more these parameters because of the higher protein content of these formulations. After simulated digestion, a high polyphenol bioaccesibility was observed, and the antioxidant activity was retained, which could be explained by the “protector” effect of the milk matrix.

Yogurt supplementation with green tea polyphenols is feasible for the development of functional food. However, the use of protein particles would not provide an extra benefit because milk proteins already act as protective molecules of polyphenols.

This study shows not only the physico-chemical implications of including polyphenols in yogurt but also their bioaccesibility after an in vitro digestion, revealing a suitable manner for delivery of antioxidants in a dairy product like yogurt.

The purpose of this paper was to determine total polyphenols (TP), total flavonoids (TF) and (-)-epigallocatechin gallate (EGCG) in five commercial tea extracts and in their infusions at various temperatures (95-60°C) and brewing times (5-30 min).

TP was determined by the Folin–Ciocalteu method, TF by the aluminium chloride colorimetric method and EGCG by HPLC method.

The results showed that White tea – Silver needle had the highest content of TP and EGCG when extracted, but its infusions had very poor concentrations of these compounds. Green tea infusion was better source of TP and EGCG than white or black tea, although its extract did not contain a very high amount of TP compared to the latter two types. Black tea extract had a relatively high content of TP and TF in its extract. Its infusions as well contained higher concentrations of TP than white tea, but lower concentrations of EGCG than all studied teas.

Increasing infusion time and temperature does not necessarily increase the concentration, according to the results. To the authors’ knowledge, this is the first report on comparing these types of tea, especially the white tea, with other well-known teas under various infusion conditions. The extraction of the white tea leaves was also not found in previous works.

Metabolic syndrome (MetS) is a complex disorder that exacerbates the risk of cardiovascular disease and diabetes mellitus; some studies have indicated the beneficial effects of green tea on human health. The purpose of this study is to investigate the effects of green tea consumption on the MetS indicators in women.

A randomized clinical trial was carried out on 70 eligible women with confirmed diagnosis of MetS who visited Shabani Diabetes Clinic (Isfahan, Iran). Participants were randomly divided into two groups. Participants in the Green Tea Group were asked to consume three 200 cc of green tea in the morning, at noon and at night for eight weeks, while people in the control group were asked to take identical amount of lukewarm water at the same schedule. Anthropometric indicators, blood pressure, blood sugar, lipid profile, diet and physical activity were assessed at the beginning and the end of the study.

An independent t-test showed that weight (p = 0.001), body mass index (p = 0.001), waist circumference (p < 0.001) and waist–hip ratio (p = 0.02), systolic blood pressure (p = 0.04), fasting blood glucose (p = 0.01) and low density lipoprotein (p = 0.03) changed significantly more in the Green Tea Group than in the control group; but no such inter-group difference was observed in diastolic blood pressure, triglyceride, total cholesterol and high density lipoprotein (HDL) values (p > 0.05).

Regular consumption of green tea for eight weeks significantly improved anthropometric indices, blood pressure, blood sugar and lipid profile in women with MetS. Therefore, this beverage can serve as part of an effective dietary strategy to control MetS.

It is argued that COVID-19 patients show various neuropsychiatric symptoms, including fatigue, depression and anxiety. On the other hand, epidemiological and experimental evidence indicated that green tea could potentially have antiviral effects and ameliorate psychiatric disorders. However, there is a lack of clinical evidence. The purpose of this study was to investigate whether drinking green tea can clinically improve psychiatric complications of COVID-19 infection.

This study included 40 patients with laboratory confirmed mild-to-moderate COVID-19 disorder in the current randomized open-label controlled trial. Patients were instructed to include three cups/day of green tea (intervention) or black tea (control) to their usual diet for four weeks immediately after diagnosis of the disease. At the study baseline and after the intervention, the enrolled patients’ fatigue, depression and anxiety were assessed by the Chalder Fatigue Scale, Beck Depression Inventory-Fast Screen and State-Trait Anxiety Inventory questionnaires.

A total of 19 COVID-19 cases in the intervention group (mean age = 52 years) and 14 cases (mean age = 50 years) in the control group completed the study. Analysis of covariance adjusted for baseline levels, and confounders revealed that those who consumed three cups/day of green tea compared to the patients who received black tea experienced significantly lower fatigue, depression and state and trait anxiety levels (adjusted means for fatigue = 12.3 vs 16.2 (P = 0.03), depression = 0.53 vs 1.8 (P = 0.01), 37.4 vs 45.5 (P < 0.01) and 37.9 vs 45.2 (P < 0.01)).

The open-label design may bias the evaluation of the self-reported status of fatigue, depression or anxiety as the main outcomes assessed. Moreover, as this study did not include patients with severe COVID-19, this might affect the generalizability of the present results. Thus, the recommendation of daily drinking green tea may be limited to the subjects diagnosed with mild-to-moderate type of infection or those with long-term neuropsychiatric complications owing to COVID-19. Besides, considering the ethical issues, this study could not exclude the drug therapy’s confounding effects; thereby, this point should be considered when interpreting the current results. Besides, it is worth noting that Guilan province in the north of Iran is recognized as a tea (and particularly green tea) producing region; thereby, it is an available and relatively inexpensive product. Considering this issue, the recommendation to consume this medicinal plant in adjunct to the routine treatment approach among patients with mild-to-moderate COVID-19 based on its beneficial effects may be widely accepted.

Green tea consumption could be considered an option to combat COVID-19 associated psychological complications, including fatigue, depression and anxiety among patients suffering from mild-to-moderate type of this viral infection.

To the best of the authors’ knowledge, in this study, for the first time, the effects of green tea compared to black tea on COVID-19 associated fatigue, depression and anxiety status within an open-label controlled trial have been investigated.

The prayer against the Poultry (Hygiene) Regulations which we briefly mentioned in the editorial of our last issue, was lodged as a result of activity by the Environmental Health Officers' Association. Incidentally it is the first occasion as far as we can recall that a prayer has been lodged against any of the rash of food regulations of recent years, and reflects the strong feelings of the public health inspectorate.

White tea is an unfermented tea made from young shoots of Camellia sinensis protected from sunlight to avoid polyphenol degradation. White tea contains a high level of polyphenolic compounds known as catechins. Several types of evidence have suggested that tea consumption has benefits in body weight and endurance maintenance. This study was designed to evaluate the effect of white tea on body weight and endurance of animal models.

This research was an intervention design using 20 Wistar white rats (Rattus Norvegicus) in body weight between 150 and 200 g. The rats were randomized into four groups, three groups receiving white tea drink (WTD) with different doses and the other group receiving plain water in equal volume as a control group for four weeks. The forced swim test (FST) was done to measure their struggling capacity, and digital bodyweight to measure the weight.

Intervention (WTD Groups and Control) caused weight gain among except G3 with the highest doses of white tea. The result showed that WTD intake in G3 had a significant difference (p < 0.05) on body weight gain compared to control. The authors found that WTD in a specific dose (G3: 0.22 mg) tends to maintain the body weight of animals (219.2 ± 41.96; 212.6 ± 46.90, respectively), while other doses caused weight gain. WTD also significantly increased the swimming and struggling capacity of rats that represented improvements the endurance along with the test. There was a statistically significant difference in endurance among all groups (p < 0.05).

The results of this study can be followed as human intervention research as an input for nutritionists and sports scientists to explore the beneficial effect of white tea.

The results of this study can be followed as human intervention research as an input for nutritionists and sports scientists to explore the beneficial effect of white tea.

This study adds more evidence and information about the advantages of white tea as potential beverages in future healthy lifestyles.

The purpose of the study is to highlights the conceptual and scientific knowledge regarding bioavailability of food bioactive components which is essential for the thorough understanding of their role in disease prevention and factors that limit their absorption.

Nutrikinetics is an extended version of pharmacokinetics that is used for studying the bioavailability and bioaccessibility of components through different techniques such as metabolic profiling, multi-level data analysis and population-based modeling.

There are different phases of nutrikinetics study of the bioactive components. The initial stage of nutrikinetics is starting from simplest in-vitro assay which is applicable in the early stage of functional foods development. Thereafter, the next stage of nutrikinetics studies are related to human intervention studies as designed by European Food Safety Authority. The aim of such studies are to develop dose-exposure and exposure response study of a bioactive component.

This paper will enlighten the concept of nutrikinetics, its requirement and the future perspectives of nutrikinetics study including long-term efficacy studies and multi-compartmental analysis of the different bioactive components.

The purpose of this paper is to investigate the effects of green tea extract on kidney function tests, in male rats that received different doses of acrylamide (AA).

Animals were dispensed at random to one of the following treatments: group 1 served as control, whereas groups 2, 3 received seven, 14 mg/100 g B.W/day of AA, respectively, in drinking water for 15 and 30 days. Group 4 received green tea 1.5 percent concentration and groups 5, 6 received seven, 14 mg/100 g B.W/day in a mixture with green tea for 15 and 30 days.

Serum urea and creatinine significantly increase with AA. However, Total protein, albumin and A/G ratio showed significant drop in all treated groups when compared with control. Supplementation of rats with antioxidant (green tea) enhanced the general health condition, reduced the severity of genotoxic effect and the alteration in blood and serum parameters produced by AA.

The authors suggest that green tea may deliver a cushion for long therapeutic option against toxins-induced nephrotoxicity without damaging side effects.

The study uses green tea as a natural antioxidant source. Epigallocatechin-3 gallate is the most plentiful catechin preserved in green tea and a high source of flavonoids. Flavonoids are a group of phenolic products of plant metabolism with high antioxidant properties to reduce nephrotoxicity without side effects.

The purpose of this paper is to investigate the health and medicinal importance of bush tea (Athrixia phylicoides DC) and special tea (Monsonia burkeana Planch. ex Harv), two of Southern African indigenous herbal teas.

The two herbal teas, A. phylicoides and M. burkeana were extracted individually and in combined ratios for analysis. The phenolic content was determined and the different phenolic compounds were identified using thin-layer chromatography (TLC) and high-performance liquid chromatography (HPLC). The anti-diabetic activity of the teas was determined by evaluating the inhibition of both α-amylase and α-glucosidase in vitro. The anti-proliferative activity was measured on human cervical cancer (HeLa) cell line using the MTT (3-(4,5-dimethylthiazol-2-yl)2,5-diphenyltetrazolium) assay.

Gallic acid, chlorogenic acid and quercetin were identified to be present in significant quantities by TLC. The HPLC quantified the presence of catechin (1.567 mg/g) and chlorogenic acid (1.862 mg/g) in special tea while chlorogenic acid (1.288 mg/g) was present in bush tea. Bush tea and special tea expressed significant levels of phenolic content and high antioxidant activities. Special tea (S100) expressed high inhibition of α-amylase, α-glucosidase and HeLa cell line proliferation when compared to bush tea (B100).

Both bush tea and special tea could provide an alternative for treatment and management of both diabetes and cervical cancer. However, future studies are needed to investigate their synergistic effect with a wide range of other commercial herbal teas.

This study was carried out to examine the effect of cocoa extract (CE) on plasma glucose levels in hyperglycaemic rats induced with streptozotocin. Three concentrations of CE were used to study its effect on oral glucose tolerance test (OGTT). In the normal group, CE at 0.5 per cent concentration had significantly reduced the glucose level (p<0.05) at 0 and 60 min, 1.0 per cent at 0 (p<0.05), 60 (p<0.01) and 180 min (p<0.01), 3.0 per cent at 60 (p<0.05) and 180 min (p<0.01) as compared to control. In hyperglycaemic group, 3.0 per cent CE had reduced the glucose level significantly (p<0.05) at 60 as compared to control. Based on the results from OGTT, 3.0 per cent concentration was used to evaluate the effect of CE in a 2‐week study. There was no significant difference in reduced plasma glucose levels and lipid profiles in hyperglycaemic and normal rats, which were given basal diet enriched with 3.0 per cent CE extracted from cocoa powder as compared to the control (basal diet).