Consumer preference for clean-label products is driving interest in natural antioxidants and antimicrobials that can replace synthetic preservatives. Ziziphus mauritiana (sidr), a resilient desert tree native to the arid Gulf region, has being tested as a multifunctional bio-preservative. This study evaluated the extraction yield, total phenolic content (TPC), total flavonoid content (TFC), antioxidant and antimicrobial activities, and poultry meat-preserving potential of Z. mauritiana. Methanol and ethanol produced the highest extract recoveries, with bark exhibiting the maximum extraction yield of up to 10.7 mg/100 g. Fruits demonstrated the highest total phenolic content (TPC) of around 175 mg gallic acid equivalents per gram (GAE/g) and total flavonoid content (TFC) of around 7.4 mg catechin equivalents per gram (CE/g), followed by leaves and bark. The antioxidant activity was significantly correlated with the concentration of phenolic compounds in the fruit extracts, which exhibited DPPH inhibition exceeding 60% in the majority of instances. The RP-HPLC investigation revealed a diverse polyphenolic profile, predominantly featuring gallic acid (up to 8.77 mg/g in leaves), catechin (6.30 mg/g in fruits), catechol, and caffeic acid. Leaf extracts showed 24 mm inhibitory zones against E. coli and Y. enterocolitica, while bark and fruit were not very effective. Adding ethanolic leaf extract (0–1%) to chicken breast meat reduced microbial degradation during chilled storage at 4 °C. At day 15, total aerobic counts reached only 5.34 log CFU/g with 1% extract compared with 8.53 log CFU/g in the control. Similar suppression was found for yeasts and molds, while challenge tests showed >3-log reductions in C. jejuni and Salmonella senftenberg. Sensory evaluation confirmed no detrimental effects on color, odor, flavor, or texture. Overall, Z. mauritiana was a valuable, renewable source of phenolic antioxidants and antimicrobial agents and showed strong promise as a natural preservative capable of improving the safety and shelf life of poultry meat in clean-label applications.
Shehata et al. (Wed,) studied this question.