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Some Fungi Degrade Polyurethanes

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Conidia and conidiophore of Cladosporium cladosporioides  (Source: commons.wikimedia.org) Fungi , a separate kingdom in living organisms, includes vast numbers of species with diverse usage to humanity and roles in the ecosystem. They are known to have a potential to reduce human-induced pollution by degrading numbers of toxic as well as non-toxic xenobiotics and transforming a wide variety of hazardous chemicals. In a recent study done by a group of scientists under the leadership of Ivano Brunner from Switzerland showed an ability of fungi to degrade plastic waste in the environment. The results are published in the PLOS ONE journal (Date: August 22, 2018) showing the power of fungi isolated from plastic debris floating in the shoreline of  Zurich lake, Switzerland, to degrade plastics.  Memory foam cushion made up of viscoelastic polyurethane (Source: commons.wikimedia.org) The team of researchers isolated over a hundred fungal strain...

How to Determine Cytotoxic Activity of Crude extracts by MTT assay

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After total flavonoids content (TFC), total polyphenolics content (TPC), and antioxidant activity of different crude extracts of orchid including Dondrobium longicornu have been estimated, we decided to determine their cytotoxic activity using MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on human brain tumor cells ( U251 ) and cervical cancer cells ( HeLa ).  We employed previously established protocols (Mosmann, 1983; Sargent and Taylor, 1989) which is presented below point wisely.  Culture human brain tumor cells (U251) and cervical cancer cells (HeLa) in RPMI 1640 medium and incubate them under 5% CO 2 at 37 ° C for 48 hours to reach  80% confluence. Harvest by gentle scraping with a cell scraper and resuspended in the medium.  Dispense 100 μ L of such medium with 5 × 10 3 cells into each well of 96-well microtiter cell culture plate and incubated under the same conditions of cell culture for 48 hours to...

The Rapid Method of Estimating Antioxidant Activity and Total Polyphenols Content of Sample Plant Extracts

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Estimation of total polyphenols content Figure1. The appearance of bluish-black colour after the addition of reagents on sample plant extracts during the estimation of total polyphenols content.  We estimated  total polyphenol content  by a standard protocol (Singleton et al . 1999 and Stankovic 2011) with slight modification. Briefly, we  separately mixed  each plant extract (0.5 ml; 1 mg/ml)  with the Folin-Ciocalteu phenol reagent (2.5 ml; 10%) and aqueous sodium bicarbonate solution (2.5 ml; 7.5%). Then, the reaction mixture was allowed to stand for about 45 minutes and the absorbance was measured at 765 nm using the UV- spectrophotometer (Thermo Fisher Scientific, Genesystem -10.5).The calibration curve was plotted using gallic acid as standard in ethanol (absolute) using the concentration series of 25, 50, 75, and 100 µg/ml. Here, the reagent mixture with the  same volume of ethanol instead of plant extract solution was used ...

How we performed the estimation of total flavonoid content ?

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This time I am sharing a method for the estimation of total flavonoid content in our experiments. We Flowchart. the process of estimating total flavonoids content. followed a previously done standard protocol  (Quettier  et al.  2000 and Stankovic 2011)  with slight modification.  Firstly, we  mixed  e ach plant extract (2 ml; 0.5 mg/ml) separately  with aluminium chloride solution (1 ml; 2 %). Then, we allowed the reaction mixture to stand for an hour at room temperature. Again, we measured the absorbance of the mixture at 415 nm using the UV-spectrophotometer. We  obtained  calibration curve (see Fig 1.) using quercetin solution series (25, 50 75, and 100 µg/ml) as a standard. Here, we used the reagent mixture with the same volume of ethanol instead of plant extract solution as a blank. Thus, the obtained curve was calibrated to estimate the concentration of total flavonoid in each plant extract. The total ...