*4.5. Chlorophyll Content*

It has been confirmed that ethanol retards chlorophyll degradation [45], repining and senescence [46]. The maintained chlorophyll content of the samples treated with ethanol is due to its inhibited effects on the activities and gene expression of chlorophyll enzymes [21]. It has been reported that AsA reduced the degradation of chlorophyll, which is correlated to photosystem and therefore resulted in higher chlorophyll content [47]. Our results shown in Figure 1d are in concurrence with Barzegar et al. [42], who found that AsA treatment maintained chlorophyll content in stored sweet pepper and green chilies, respectively.

Our results indicated that PMO and TTO treatments had a positive role in maintaining the chlorophyll content of fresh-cut green beans. This effect can be explained by a lower breakdown of chlorophyll pigments induced by PMO treatment, which acts as a coating agent [48]. Moreover, the thin coating layer around samples formed by TTO treatment could protect them from oxidation and colour changes [49].
