Antagonism of phenanthrene cytotoxicity for human embryo lung fibroblast cell line HFL-I by green tea polyphenols

Current understanding on antibacterial mechanisms and research progress of tea polyphenols as a supplementary disinfectant for drinking water

Disinfection by-products (DBPs) generated during the disinfection of drinking water have become an urgent problem. So, tea polyphenol, a natural green disinfectant, has attracted widespread attention in recent years. This review summarizes the antibacterial mechanism of tea polyphenols and the recent findings on tea polyphenols as disinfectants for drinking water. These studies show that tea polyphenol is an antibacterial agent that works through different mechanisms and can be used as a supplementary disinfectant because of its higher lasting effect and economical cost. The dosage of tea polyphenols as a disinfectant of ultrafiltration effluent is the lowest among all the tea polyphenols disinfection methods, which can ensure the microbial safety of drinking water. This application of tea polyphenols is deemed a practical solution to solving the issue of disinfecting drinking water and reducing DBPs. However, it is necessary to further explore the influence of factors such as pipeline materials on the disinfection process and efficacy to expand the application scope of tea polyphenols. The large-scale application of tea polyphenols still needs to be fine-tuned but with new developments in tea polyphenol purification technology and the long-term need for drinking water that is safe for human consumption, tea polyphenols have good prospects for further development.

Degradation and detoxification of phenanthrene by actinobacterium Zhihengliuella sp. ISTPL4

Polycyclic aromatic hydrocarbons (PAHs) are universal environmental contaminants of great concern with regard to their potential exposure and deleterious effect on human health. The current study is the first report of phenanthrene degradation by a psychrotolerant (15 °C), halophilic (5% NaCl), and alkalophilic (pH 8) bacterial strain Zhihengliuella sp. ISTPL4, isolated from the sediment sample of the Pangong Lake, Ladakh, Jammu and Kashmir, India. Degradation studies revealed that the optimum specific growth rate was observed at 250 ppm of phenanthrene with 81% and 87% removal of phenanthrene in 72 h and 168 h, respectively. During the degradation of phenanthrene; 9,10-dihydrophenanthrene; 1-phenanthrenecarboxylic acid; and phthalic acid were detected as intermediates. Whole-genome sequencing of strain ISTPL4 has predicted phenanthrene; 9,10-monooxygense; and epoxide hydrolase B that are involved in the phenanthrene metabolism. Phenanthrene cytotoxicity was evaluated with human hepatic carcinoma cell line (HepG2) and it was observed that the cytotoxicity decreased with increased duration of bacterial incubation and maximum cell viability was observed at 168 h (89.92%). Our results suggest, Zhihengliuella sp. ISTPL4 may promise a great potential for environmental remediation applications.

Consequences of hydrogenated vegetable fat substitution with Ajwa seed oil on physicochemical and nutritional aspects of functional cookies

The core objectives of the current study were to explore and compare the proximate and nutritive composition of both types of cookies prepared either with Ajwa seed oil (ASO) or hydrogenated vegetable fat (HVF) and comparative analysis of the antioxidantal potential of both cookies and to reconnoiter the storage effects on the quality parameters of the cookies over a period of 60 days. Outcomes revealed that the cookies prepared with the ASO were superior (p < .05) in fat% and energy as compared to the cookies with HVF. Due to the presence of functional moieties, ASO cookies were found with better palatability, increased shelf life with enhanced physical properties and better functionality. Therefore, the findings of the current study revealed that ASO could be used as an alternative fat source for the preparation of novel functional cookies instead of conventional vegetable fats.

Green tea polyphenols and their potential role in health and disease

There is a growing body of evidence that plant polyphenols such as resveratrol, anthocyanins, catechins, and terpenes like taxol are effectively used in the treatment of chronic conditions including cancer, Alzheimer, Parkinsonism, diabetes, aging, etc. The link between oxidative stress and inflammation is well accepted. Thus, the mechanism of action of these natural products is partly believed to be through their significant antioxidant properties. The main constituent of green tea, with clinical significance, is epigallocatechin gallate (EGCG). It has been associated with antitumor, anti-Alzheimer, and anti-aging properties, improve redox status at the tissue level possibly preventing system level structural damage. This review focuses on EGCG and its potential therapeutic role in health and disease.

Interaction effects of polycyclic aromatic hydrocarbons and heavy metals on a soil microalga, Chlorococcum sp. MM11

Environmental risk assessment of sites contaminated with chemicals needs to also consider mixtures of chemicals as these toxicants act more differently in a mixture than when they occur alone. In this study, we describe, for the first time, the use of a full factorial design experiment to evaluate the toxicity of a quaternary mixture comprising two polycyclic aromatic hydrocarbons (PAHs; benzo[a]pyrene (BaP) and phenanthrene (Phe)) and two heavy metals (cadmium (Cd) and lead (Pb)) toward a soil microalga, Chlorococcum sp. MM11. Biomass, in terms of cell number, and proline accumulation were used to evaluate toxicity responses. Factorial analysis of the data revealed statistically significant interaction effects between the mixtures of toxicants on 96-h biomass endpoint, while no significant interaction effects were observed on proline accumulation in the microalga. A comparison of the data on the toxicity of individual chemicals and those of the factorial main effect analysis clearly showed that Cd is more toxic to the alga, followed by BaP, Pb, and Phe. There was a substantial heavy metal accumulation and PAH degradation by the strain MM11 at EC10 and EC50 of the chemical mixtures.

Black tea polyphenols: a mechanistic treatise

Dietary interventions are among the emerging trends to curtail physiological malfunctioning like cancer, diabetes, cardiac complications, etc. The essence of phytonutrients has developed the concept of nutraceuticals at the junction of diet health linkages. In this context, theaflavin & thearubigins are the oxidized derivatives of black tea catechins during fermentation having nutraceutical potential owing to esterification of hydroxyl ring with digallate esters. Theaflavin may influence activation of transcription factors such as NFnB or AP-1 that ultimately hinder the formation of nitric oxide expression gene. Likewise, black tea contains a unique amino acid theanine acts as neurotransmitter owing to its ability to cross the blood-brain barrier. Moreover, it boasts immunity by enhancing the disease-fighting ability of gamma delta T cells. Theaflavin & thearubigins act as safeguard against oxidative stress thereby effective in the cardiac functioning. The mechanistic approach of these antioxidants is likely to be associated with inhibition of redox sensitive transcription factors & pro-oxidant enzymes such as xanthine oxidase or nitric oxide synthase. However, their involvement in antioxidative enzyme induction as in glutathione-S-transferases is also well documented. They act as curative agent against numerous pathological disorders by disrupting the electron chain thus inhibiting the progression of certain ailments. Black tea polyphenols established themselves as strong antioxidants due to their standard one-electron potential, and their vitality is dependent on the concentration of polyphenols and pH for their inclusive execution. Present review is an attempt to enrich the readers regarding the health promoting aspects of black tea polyphenols. Concomitantly, it needs core attention of researchers for the exploitations of black tea flavanols as an important dietary constituent for the vulnerable segment.