Polyphenols extraction from creosote bush, tarbush, and soursop using ultrasound-microwave and their effect against Alternaria alternata and Fusarium solani

Abstract

<p>Crops are affected by different pathogens that cause damage to the plant and production losses. Quarantine restrictions may also occur due to the presence of a pathogen. In most cases, synthetic chemical products are used to control phytopathogens. However, some of these products have been associated with risks to human health or the environment. Therefore, it is necessary to search for more sustainable alternatives to control these pathogens. This research was carried out under the following objectives: 1. To extract polyphenols from Creosote bush, Tarbush and Soursop leaves using: different mass/volume ratios (m/v), different concentrations of ethanol, simultaneous ultrasound-microwave and 2. To determine the effect of these polyphenols against <em>Fusarium solani</em> and <em>Alternaria</em> <em>alternata</em>. Polyphenols were obtained from Creosote bush, Tarbush and Soursop leaves by combining ultrasound-microwave, and using different massvolume ratios and ethanol percentages. The group of polyphenols (CD) obtained with a mass/volume (m/v) ratio of 1:8 and 70% ethanol from Creosote bush leaves and the group of polyphenols (CA) obtained with a m/v ratio 1:16 and 70% ethanol from Tarbush leaves were the most effective against <em>Fusarium</em> <em>solani</em>, inhibiting 90.4 and 60.67%, respectively. For <em>Alternaria alternata</em>, no differences were found in the mycelial inhibition by the different groups of evaluated polyphenols, with inhibition values between 50-60% in comparison to the negative control (without polyphenols). In the profile of CD polyphenols group obtained from Creosote bush, different polyphenolic compounds reported to have antimicrobial activity were found, among which the following stand out: epirosmanol, rosmadiol, apigenin, catechin, and procyanidin C1. Polyphenolic compounds isolated from Creosote bush, Tarbush, and Soursop leaves using environmentally friendly methods (ultrasoundmicrowave) and solvents (water and ethanol) showed antifungal activity against <em>F. solani</em> and <em>A. alternata</em>.</p>