Dammak Islem, Abdelkefi Nourelhouda, Atitallah Imen Ben, Brysch-Herzberg Michael, Alessa Abdulrahman H, Lasram Salma, Zouari-Mechichi Hela, Mechichi Tahar
Laboratory of Biochemistry and Enzymatic Engineering of Lipases, National Engineering School of Sfax (ENIS), University of Sfax, 3038, Sfax, Tunisia.
Hochschule Heilbronn, Heilbronn University Fakultät für International Business, Max-Planck-Str. 39, 74081, Heilbronn, Germany.
Heliyon. 2024 Oct 16;10(20):e39504. doi: 10.1016/j.heliyon.2024.e39504. eCollection 2024 Oct 30.
Seven yeast strains were isolated from Tunisian dates. The strains were identified by sequence analysis of the D1/D2 domain of the nuclear large subunit (LSU) rRNA gene. Based on this all strains in the study were almost identical with that of the type strain of (CBS 5767) indicating that they belong to this species. All strains were characterized physiologically and biochemically. All strains grew in the presence of 50 % sucrose, 10 % sodium chloride and at 42 °C. The potential of these yeasts as biocontrol agent against mycotoxigenic species inhabiting date, was evaluated. All yeast strains inhibited the growth of P10 and C17 previously isolated from dates, with inhibition percentages ranging between 43.6 % and 70.3 % on dual culture plate assays. Moreover, the volatile compounds (VCs) produced by these yeasts inhibited the mycelial growth rate and sporulation of both fungus strains, up to 76.5 and 100 %, respectively, on inverted culture plate assay. The VCs of strains Y4 and Y24, which exhibit strong inhibitory activity against toxigenic , were determined by head-space solid-phase microextraction (HS-SPME) combined with gas chromatography coupled with mass spectrometry (GC-MS) analysis. Results revealed significant levels of alcohols (27.36 % for Y4 and 23.35 % for Y24) and esters (66.19 % for Y4 and 75.82 % for Y24). Their significant bioactivity, along with the lack of reported adverse effects on consumer health or the environment, makes them a sustainable and effective alternative to synthetic fungicides for the biocontrol of mycotoxigenic affecting stored dates.
从突尼斯枣中分离出七株酵母菌株。通过对核大亚基（LSU）rRNA基因的D1/D2结构域进行序列分析来鉴定这些菌株。基于此，研究中的所有菌株与（CBS 5767）模式菌株几乎相同，表明它们属于该物种。对所有菌株进行了生理生化特性分析。所有菌株都能在50%蔗糖、10%氯化钠存在的条件下以及42℃生长。评估了这些酵母作为生物防治剂对栖息在枣中的产毒霉菌物种的潜力。所有酵母菌株都抑制了先前从枣中分离出的P10和C17的生长，在双培养平板试验中，抑制率在43.6%至70.3%之间。此外，这些酵母产生的挥发性化合物（VCs）抑制了两种真菌菌株的菌丝生长速率和孢子形成，在倒置培养平板试验中，抑制率分别高达76.5%和100%。通过顶空固相微萃取（HS-SPME）结合气相色谱-质谱联用（GC-MS）分析，确定了对产毒霉菌具有强抑制活性的Y4和Y24菌株的挥发性化合物。结果显示，醇类（Y4为27.36%，Y24为23.35%）和酯类（Y4为66.19%，Y24为75.82%）含量显著。它们显著的生物活性，以及未报道的对消费者健康或环境的不利影响，使其成为用于生物防治影响储存枣的产毒霉菌的合成杀菌剂的可持续且有效的替代品。
