On-Chip Cytotoxicity Testing of Nepali Chiya Extract

Here, we report a threshold limit value (TLV) of on-chip cytotoxicity of Nepali Chiya, the Nepali traditional black tea. To demonstrate our proof-of-concept validation, we used the active sealing chip with serial dilution that can directly perform on-chip cytotoxicity testing onto the cells cultured in a petri dish. In our experiments, the TLV for mortality on HeLa cells was observed as 400 μg/ml for Nepali Chiya extract. We believe this approach would be a rapid and simple method for on-chip TLV screening of potability of tea extract at the laboratory level, and furthermore as a new potential drug supplement in pharmaceutical industries.

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Rotary Beveling for In Situ Thin-Section Microscopy of Cell Cultures

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100099192 ◽

1981 ◽

Vol 39 ◽

pp. 550-551

Author(s):

Dean A. Handley ◽

Jack T. Alexander ◽

Shu Chien

Keyword(s):

Cell Growth ◽

Cell Cultures ◽

Molecular Interactions ◽

Convenient Method ◽

Petri Dish ◽

Simple Method ◽

Thin Section Microscopy ◽

Thin Sectioning ◽

Organic Fluids

In situ preparation of cell cultures for ultrastructural investigations is a convenient method by which fixation, dehydration and embedment are carried out in the culture petri dish. The in situ method offers the advantage of preserving the native orientation of cell-cell interactions, junctional regions and overlapping configurations. In order to section after embedment, the petri dish is usually separated from the polymerized resin by either differential cryo-contraction or solvation in organic fluids. The remaining resin block must be re-embedded before sectioning. Although removal of the petri dish may not disrupt the native cellular geometry, it does sacrifice what is now recognized as an important characteristic of cell growth: cell-substratum molecular interactions. To preserve the topographic cell-substratum relationship, we developed a simple method of tapered rotary beveling to reduce the petri dish thickness to a dimension suitable for direct thin sectioning.

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EXPERIMENTAL SUBSTANTIATION OF THE MAXIMUM ALLOWABLE CONCENTRATION OF DIOCTYL TEREPHTHALATE IN THE AIR OF THE WORKING AREA

Токсикологический вестник ◽

10.36946/0869-7922-2020-1-34-38 ◽

2020 ◽

pp. 34-38

Author(s):

A. S. Radilov ◽

S. A. Solntseva ◽

I. E. Shkaeva ◽

S. A. Dulov ◽

E. V. Vivulanets ◽

...

Keyword(s):

Central Nervous System ◽

Nervous System ◽

Functional State ◽

Hematological Parameters ◽

Inhalation Exposure ◽

Threshold Limit Value ◽

Maximum Allowable Concentration ◽

Limit Value ◽

Threshold Limit ◽

The Central Nervous System

Toxicity and hazard assessment of dioctyl terephthalate (DOTP) was performed in acute, subacute, and chronic experiments, and its principal toxicometry parameters were determined.It was found that on single exposure DOTP exhibits low toxicity and hazard. No resorptive and irritant effects on skin and mucous membrane of eyes were detected in animal experiments. The single inhalation exposure threshold limit value was set at 300 mg/m3, based on the results of monitoring of the functional state of the central nervous system and myocardium and hematological parameters.Thirty-day subacute experiments (oral administration, inhalation exposure, and skin applications) revealed no accumulation of the compound.Four-month chronic exposure to DOTP aerosols (concentration 96,8 mg/m3) caused disorder of the functional state of the central nervous system and myocardium, changes in the hematological and biochemical parameters, gas and acid-base status of the blood, and morphological changes in the lungs and heart. Embryotoxic, genotoxic and gonadotoxic effects were not detected.The chronic inhalation exposure threshold limit value for DOTP (Limch) was set at 18,6 mg/m3, and the concentration of 3,4 mg/m3 was found to be ineffective.The maximum allowable concentration of DOTP in the air of the working area was set at 3,0 mg/m3, hazard class 3.

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Theaflavin Enriched Black Tea Extract Alleviates Diabetic Nephropathy by Suppressing Hyperglycaemia-Mediated Oxidative Stress and Inflammation in Streptozotocin-Induced Rats

The Natural Products Journal ◽

10.2174/2210315510999200607182700 ◽

2020 ◽

Vol 10 ◽

Author(s):

Dhrubajyoti Sarkar ◽

Sekhar Kumar Bose ◽

Tania Chakraborty ◽

Souvik Roy

Keyword(s):

Oxidative Stress ◽

Diabetic Nephropathy ◽

Blood Glucose ◽

Blood Urea Nitrogen ◽

Phenolic Content ◽

Black Tea ◽

Total Phenolic ◽

Urea Nitrogen ◽

Black Tea Extract ◽

Tea Extract

Background: Diabetic nephropathy (DN), a microvascular complication of diabetes has been a significant health issue globally. However, theaflavin enriched black tea extract (BTE-TF) could restrain DN. Objective: The main objective of this exploration was to elucidate the effect of BTE-TF on DN, though the underlying mechanism remains unclear and requires further investigation. Method: The tea leaves were fermented to get black tea extract. Total phenolic content and HPLC were carried out to determine the phenolic content and theaflavin in the extract. Streptozotocin induced diabetic rats were treated with 100, 200, and 400 mg/kg/day BTE-TF extract for 12 weeks. Biochemical parameters like blood glucose, creatinine, blood urea nitrogen (BUN), triglyceride and antioxidant parameters of kidney tissue were measured. Histology, immunohistochemistry and TUNEL assay were performed to observe the effect of the extract with comparison to the standard drug (Metformin 200mg/kg/day). Result: Treated animals exhibited reduced blood glucose levels, blood urea nitrogen (BUN), creatinine, and serum triglycerides. Further, BTE-TF restored the histological alterations in the kidney. Chronic hyperglycaemia resulted in a significant increase in oxidative stress and pro-inflammatory cytokines of NF-kβ pathway. BTE-TF attenuated oxidative stress (p<0.01), inflammation (p<0.05) and apoptosis (p<0.05). Conclusion: This study suggests that BTE-TF exerts a protective role against diabetes-induced renal injury by ameliorating oxidative stress, inflammation, and apoptosis.

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Development and Characterization of Functional Starch-Based Films Incorporating Free or Microencapsulated Spent Black Tea Extract

Molecules ◽

10.3390/molecules26133898 ◽

2021 ◽

Vol 26 (13) ◽

pp. 3898

Author(s):

Surakshi Wimangika Rajapaksha ◽

Naoto Shimizu

Keyword(s):

Antioxidant Activity ◽

Lipid Oxidation ◽

Food Packaging ◽

Uv Light ◽

Antioxidant Properties ◽

Black Tea ◽

Wall Material ◽

Food Simulants ◽

Black Tea Extract ◽

Tea Extract

Antioxidant polyphenols in black tea residue are an underused source of bioactive compounds. Microencapsulation can turn them into a valuable functional ingredient for different food applications. This study investigated the potential of using spent black tea extract (SBT) as an active ingredient in food packaging. Free or microencapsulated forms of SBT, using a pectin–sodium caseinate mixture as a wall material, were incorporated in a cassava starch matrix and films developed by casting. The effect of incorporating SBT at different polyphenol contents (0.17% and 0.34%) on the structural, physical, and antioxidant properties of the films, the migration of active compounds into different food simulants and their performance at preventing lipid oxidation were evaluated. The results showed that adding free SBT modified the film structure by forming hydrogen bonds with starch, creating a less elastic film with antioxidant activity (173 and 587 µg(GAE)/g film). Incorporating microencapsulated SBT improved the mechanical properties of active films and preserved their antioxidant activity (276 and 627 µg(GAE)/g film). Encapsulates significantly enhanced the release of antioxidant polyphenols into both aqueous and fatty food simulants. Both types of active film exhibited better barrier properties against UV light and water vapour than the control starch film and delayed lipid oxidation up to 35 d. This study revealed that starch film incorporating microencapsulated SBT can be used as a functional food packaging to protect fatty foods from oxidation.

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