Antioxidant Activity and Cytotoxicity of Nepalese Nak Cheese

Katawal I., Kharel G.P., Poudel B.H.

Abstract: Nepal was the first country in Asia to make any Western-style cheeses, and until the 1980s certainly the only Asian country making nak Cheese (McGee, 2008). The aims of this work were to study the functional aspects of nak cheese produced in Nepal in respect to its antioxidant activity and cytotoxicity. Three nak cheeses and a cow cheese were collected randomly from regional factories of Dairy Development Corporation (DDC) in Nepal, located at altitude of 2900 m, 2600 m, 2400 m and 1900 m respectively. The cheeses were subjected to phytochemical extraction using methanol as solvent followed by quantification of the total phenol content (TPC) and flavonoid content (TFC) in their extracts. The TPC and TFC of the nak cheeses were 6.06-10.9 mg GA/g dry extract and 4.12-7.70 mg QE/g dry extract respectively which were significantly higher (p<0.05) than the cow cheese that gave the corresponding values of 2.75 mg GA/g dry extract and 1.80 mg QE/g dry extract respectively. Similarly, antioxidant activity (IC50) assayed using DPPH radicals and toxicity (LC50) determined using Brine shrimp lethality test, of the studied nak cheeses extract were 371.64-518.30 mg/L and 350.19-698.95 µg/mL (i.e., moderate toxicity) respectively. In contrast, cow cheese (1900m) gave IC50 of 626.24 mg/L, significantly lower (P<0.05) than the studied nak cheeses but its toxicity (LC50) of 376.84 µg/mL was in the range obtained for nak cheeses. Thus, nak cheese may be considered as good source of antioxidants and its regular consumption might improve consumer health due to antioxidant activity and anti-cancerous effect.

Keywords: Functional food, Nak cheese, Phytochemicals, antioxidant, cytotoxicity.

Pages: 234 – 245 | Full PDF Paper