Silva Vanessa, Silva Adriana, Ribeiro Jessica, Aires Alfredo, Carvalho Rosa, Amaral Joana S, Barros Lillian, Igrejas Gilberto, Poeta Patrícia
Microbiology and Antibiotic Resistance Team (MicroART), Department of Veterinary Sciences, University of Trás-os-Montes and Alto Douro (UTAD), 5000-801 Vila Real, Portugal.
Associated Laboratory for Green Chemistry (LAQV-REQUIMTE), University NOVA of Lisbon, 2829-516 Caparica, Portugal.
Antibiotics (Basel). 2023 Jun 21;12(7):1086. doi: 10.3390/antibiotics12071086.
Antimicrobial resistance is increasing globally and is now one of the major public health problems. Therefore, there is a need to search for new antimicrobial agents. The food industry generates large amounts of by-products that are rich in bioactive compounds, such as phenolic compounds, which are known to have several health benefits, including antioxidant and antimicrobial properties. Thus, we aimed to characterize the phenolic compounds present in pomegranate, quince, and persimmon by-products, as well as their antioxidant and antimicrobial activities. Phenolic compounds were extracted from pomegranate, quince, and persimmon leaves, seeds, and peels using a mixture of ethanol/water (80/20). The polyphenol profile of the extracts was determined by high-performance liquid chromatography. The antioxidant activity of the extracts was determined by the 2,2-diphenyl-1-picrylhydrazyl (DPPH), ferric reducing antioxidant power (FRAP), and cupric reducing antioxidant capacity (CUPRAC) methods. Antimicrobial susceptibility was evaluated using the Kirby-Bauer disk diffusion method. In general, leaves showed higher concentrations of phenolics than the peel and seeds of fruits. In total, 23 phenolic compounds were identified and quantified, with sanguiin and apigenin-3--galactoside being present in the highest concentrations. Leaf extracts of pomegranate showed higher antioxidant activities than the other components in all methods used. In general, all extracts had a greater antimicrobial activity against Gram-positive bacteria. Persimmon leaf and seed extracts inhibited a greater number of bacteria, both Gram-positive and -negative. The lowest minimum inhibitory concentration (MIC) detected among Gram-positive and -negative bacteria was 10 mg/mL for pomegranate peel and leaf extracts against and and for pomegranate leaf extract against . Our results reinforce the need to value food industry by-products that could be used as food preservatives and antibiotic adjuvants against multiresistant bacteria.
全球范围内抗菌药物耐药性正在增加，现已成为主要的公共卫生问题之一。因此，需要寻找新的抗菌剂。食品工业产生大量富含生物活性化合物的副产品，如酚类化合物，已知其具有多种健康益处，包括抗氧化和抗菌特性。因此，我们旨在表征石榴、榅桲和柿子副产品中存在的酚类化合物及其抗氧化和抗菌活性。使用乙醇/水（80/20）混合物从石榴、榅桲和柿子的叶子、种子和果皮中提取酚类化合物。通过高效液相色谱法测定提取物的多酚谱。通过2,2-二苯基-1-苦基肼（DPPH）、铁还原抗氧化能力（FRAP）和铜还原抗氧化能力（CUPRAC）方法测定提取物的抗氧化活性。使用 Kirby-Bauer 纸片扩散法评估抗菌药敏性。一般来说，叶子中酚类物质的浓度高于果实的果皮和种子。总共鉴定并定量了23种酚类化合物，其中桑色素和芹菜素-3--半乳糖苷的含量最高。在所有使用的方法中，石榴叶提取物的抗氧化活性均高于其他成分。一般来说，所有提取物对革兰氏阳性菌的抗菌活性更强。柿子叶和种子提取物对革兰氏阳性菌和阴性菌的抑制作用更强。在革兰氏阳性菌和阴性菌中检测到的最低最低抑菌浓度（MIC）为10 mg/mL，分别是石榴果皮和叶提取物对 和 以及石榴叶提取物对 。我们的结果进一步证明了重视食品工业副产品的必要性，这些副产品可用作食品防腐剂和对抗多重耐药菌的抗生素佐剂。
