NBT, NADH, Ethanol, PMS, l-ascorbic acid
1. The superoxide radicals is generated in 3 ml of TrisHCl buffer (16 mM, pH 8.0) containing 1 ml of NBT (50 μM), 1 ml NADH (78 μM) and ethanol extract of sample (25 – 50 μg).
2. The reaction was started by adding 1 ml of PMS solution (10 μM) to the mixture.
3. The reaction mixture was incubated at 25° C for 5 min, the absorbance was read at 560 nm using a spectrophotometer (Schimadzu UV-Vis 1700) against blank samples using l- ascorbic acid as a control.
4. Decreased absorbance of the reaction mixture indicated increasing superoxide anion scavenging activity.
5. The percentage inhibition of superoxide anion generation was calculated using the following formula:
% inhibition = [(A0-A1)/A0] x 100
where A0 was the absorbance of the control (l- ascorbic acid), and A1 was the absorbance in the presence of ethanol extract of sample or standards.
DPPH (2,2-diphenyl-1-picryl-hydrazyl-hydrate) free radical method is an antioxidant assay based on electron-transfer that produces a violet solution in ethanol . This free radical, stable at room temperature, is reduced in the presence of an…
Concentration of Vitamin C in Kale
IB Number: 002811-00
How do different methods of cooking, namely steaming, baking, and frying, affect the amount of ascorbic acid in Kale?
In a daily diet, arguably the most important thing to get a proper amount of is vitamins. Vitamins provide countless services and roles in the human body including helping with your immune system, repairing skin and bone tissues, and converting what you eat into…
known as ascorbic acid. Ascorbic acid, also known as vitamin C, played a key role primarily throughout the Age of Exploration.
The first indication of vitamin C was detected through a condition known as scurvy. Scurvy is a disease resulting from a deficiency of the ascorbic acid molecule. Humans and certain animals depend upon vitamin C in their diets in order to synthesize a protein known as collagen. Lack of collagen justifies the early symptoms of scurvy. Some of these symptoms include…
Through observations and results, the hypothesis ‘natural orange juice has higher vitamin C concentration than store bought juice’ contradicted and the hypothesis ‘when the temperature of the juice increases, the concentration of vitamin C in the juice decreases’ was supported. This was because manufacturers add vitamin C to appeal to markets whereas natural oranges only have natural source of vitamin C. Also, the increase in temperature destroyed vitamin C because when temperature increases,…
This may reduce post-exercise perceived muscle soreness levels and may even help in recovering from exercise bouts (Benardot, 2006).
The only negative effects of vitamin A and/or precursor consumption comes from over-indulgence. Over-consuming vitamin A may lead to toxicity that manifests itself as ?dry skin, headache, irritability, vomiting, bone pain, and vision problems? (Benardot, 2006). Beta-carotene can also be overconsumed, which may lead to a change in skin tone to a yellowish-tint…
Table 1: Experimental data for standardization of iodine solution.
Calculation of standardization factor
Standardization factor = (mass of vitamin C titrated) / (Volume of iodine solution used)
= (125g) / (41.3ml)
= 3.03 mg vitamin C/ml iodine solution
Experiment B: Vitamin C titration using fresh fruit sample to determine the content
The tabulated experimental data for this experiment is shown below (Table 2). In this experiment, the amount of vitamin C was calculated by multiplying…
Ascorbic acid is a form of vitamin C and is used as an antioxidant preservative. Ascorbic acid and its salt such as calcium ascorbate are added to food to slow down the oxidation reaction, which, for example, causes browning of newly-cut apples. Increased acidity caused by the addition of vitamin C addition, helps to prevent microbial growth and therefore preserves the freshness of the product. Provided there is good manufacturing practice, the amount of ascorbic acid that can be…
Table 2: KHP Vs. NaOH Titration data
Initial KHP acid Volume (ml)
End KHP acid volume (ml)
Volume difference (ml)
Volume of NaOH Base Used (ml)
Table 3: Titration of HCl with NaOH
Initial NaOH Volume (ml)
End NaOH base volume (ml)
Volume difference (ml)
Volume of HCl acid Used (ml)
While the binding affinity increased in urea catechol complex, cysteine catechol complex and citric acid catechol complex when compared with their individual binding energies of -3.99 kJ mol-1, -0.87 kJ mol-1 and -1.27 kJ mol-1 respectively indicating lesser inhibition effect. The results are shown in table 5 and the interactions are shown in figure 5.
Table 5: Multiple substrate simultaneous docking
Compound Binding energy
(kJ mol-1) Intermol energy
(kJ mol-1) Total internal energy…
The concept of dentin adhesion presently used involves the nanomechanical retention which is due to polymerisation of hydrophilic monomers around acid exposed collagen fibres.1 The entanglement of these monomers within the exposed collagen fibres gives rise to the so called Hybrid layer , which is also referred as Resin infiltrated Dentin layer.2 The presence of hybrid layer is important for attainment of a leakage free interface between the cavity walls and resin composite.2…