Nutritional value of plants is related to their natural compounds content and growth conditions. In this research, total phenols, favonoids, antioxidant activities and fatty acid contents of purslane (Portulaca oleracea L.) leaves and calli were studied under cold and wound stresses. For chilling stress, 7-week-old plants were incubated at 5, 10, 20, and 25 °C for one week. To induce wound, fssures were created into leaves of 8-week-old plants. Plants were maintained for 24 h under cold and normal conditions for evaluation the wounding and chilling stresses. For callus induction, stems segments were inoculated in MS medium comprising 0.5 mg L−1 naphthaleneacetic acid and 0.5 mg L−1 6-benzylaminopurine. Twelve-week-old calli were maintained at 5, 10, 20, and 25 °C for 1 week. Plants subjected to both chilling and wounding stresses showed higher phenols, favonoids and antioxidant activity than plants exposed to individual stress. Negative signifcant correlations were observed between temperature with the total phenols and favonoid contents in leaves. In this case, a similar result was observed for calli. Although in wounded plants exposed to cold stress, there was a sharp increment in the saturated fatty acids and reducing the saturated fatty acids regardless of butyric acid, saturated and unsaturated fatty acids of calli were enhanced by chilling stress. It could be concluded that chilling in calli and creating wound on the leaves subjected to lower temperatures are efective methods for improving the nutritional value of purslane .

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