Zandona Elizabeta, Vukelić Maja, Hanousek Čiča Karla, Zandona Antonio, Mrvčić Jasna, Katalinić Maja, Cindrić Ines, Abdurramani Almir, Jurina Irena Barukčić
Department of Food Technology, Karlovac University of Applied Sciences, Trg J.J. Strossmayera 9, 47000 Karlovac, Croatia.
Department of Food Engineering, Faculty of Food Technology and Biotechnology, University of Zagreb, Pierottijeva 6, 10000 Zagreb, Croatia.
Foods. 2025 Apr 25;14(9):1496. doi: 10.3390/foods14091496.
The food industry generates large quantities of biowaste, including olive ( L.) leaves, which are rich in phenolic compounds with proven antioxidant and antimicrobial activity. In this study, a microwave-assisted olive leaf extract was produced and evaluated. Antioxidant potential (20.23 ± 0.31 µmol TE g), antimicrobial activity against (MIC 17.62 mg GAE g), and cytotoxic effects in breast (MDA-MB-231 (IC = 38.9 ± 1.8 µg mL), MCF-7 (IC = 58.9 ± 5.4 µg mL) and prostate cancer PC-3 (IC = 69.2 ± 7.6 µg mL) cell models were confirmed. Further, the extract was incorporated into a whey protein isolate (WPI) edible coating mixture and applied to semi-hard cheese over a 60-day ripening period. When applied to cheese, WPI-based coatings enriched with OLE contributed to an improved antioxidant potential (289.79 ± 16.16 µmol TE L), elevated retention of total phenols and flavonoids, and slightly reduced microbial growth without compromising cheese safety. Compared to the uncoated control, coated samples showed higher total solids (up to 62.87 ± 0.13%, CWPIM) and fat contents (up to 26.59 ± 0.17%, CWPIM), moderated proteolysis (WSN in CWPIM: 3.15 ± 0.09% vs. 4.48 ± 0.02% in C0), maintained cohesiveness and resilience compared to the control, and exhibited less pronounced color deviation (ΔE) in some coated samples during ripening. These results highlight the potential of olive leaf extract as a bioactive, sustainable ingredient for functional edible coatings that improve the nutritional, technological, and microbiological quality of ripened cheese.
食品工业产生大量生物废料，包括油橄榄（Olea europaea L.）叶，其富含具有经证实的抗氧化和抗菌活性的酚类化合物。在本研究中，制备并评估了微波辅助提取的油橄榄叶提取物。证实了其抗氧化潜力（20.23±0.31微摩尔TE/克）、对大肠杆菌的抗菌活性（MIC为17.62毫克GAE/克）以及在乳腺癌（MDA-MB-231（IC50 = 38.9±1.8微克/毫升）、MCF-7（IC50 = 58.9±5.4微克/毫升））和前列腺癌PC-3（IC50 = 69.2±7.6微克/毫升）细胞模型中的细胞毒性作用。此外，将该提取物掺入乳清蛋白分离物（WPI）可食用涂层混合物中，并应用于半硬质奶酪的60天成熟期。当应用于奶酪时，富含油橄榄叶提取物（OLE）的基于WPI的涂层有助于提高抗氧化潜力（289.79±16.16微摩尔TE/升）、提高总酚和黄酮类化合物的保留率，并在不影响奶酪安全性的情况下略微减少微生物生长。与未涂层对照相比，涂层样品显示出更高的总固形物含量（高达62.87±0.13%，CWPIM）和脂肪含量（高达26.59±0.17%，CWPIM），蛋白水解作用得到缓和（CWPIM中的水溶性氮：3.15±0.09%，而C0中为4.48±0.02%），与对照相比保持了内聚性和弹性，并且在成熟过程中一些涂层样品的颜色偏差（ΔE）不太明显。这些结果突出了油橄榄叶提取物作为一种生物活性、可持续成分用于功能性可食用涂层的潜力，该涂层可改善成熟奶酪的营养、工艺和微生物质量。
