Dlamini Sicelo B, Gigante Adriano M, Hooton Steven P T, Atterbury Robert J
School of Agricultural Sciences, Faculty of Agriculture and Natural Sciences, University of Mpumalanga, Nelspruit 1200, South Africa.
School of Veterinary Medicine and Science, University of Nottingham, Sutton Bonington, Leicestershire LE12 5RD, UK.
Microorganisms. 2023 Sep 25;11(10):2389. doi: 10.3390/microorganisms11102389.
causes a range of diseases in humans and livestock of considerable public health and economic importance. Widespread antimicrobial use, particularly in intensively produced livestock (e.g., poultry and pigs) may contribute to the rise of multidrug-resistant strains. Alternative treatments such as bacteriophages have shown promise when used to reduce the intestinal carriage of in livestock. However, the digestive enzymes and low pH encountered in the monogastric GI tract can significantly reduce phage viability and impact therapeutic outcomes. This study deployed alginate-carrageenan microcapsules with and without CaCO to protect a genomically diverse set of five bacteriophages from simulated gastrointestinal conditions. None of the unprotected phage could be recovered following exposure to pH < 3 for 10 min. Alginate-carrageenan encapsulation improved phage viability at pH 2-2.5 after exposure for 10 min, but not at pH 2 after 1 h. Including 1% (/) CaCO in the formulation further reduced phage loss to <0.5 log PFU/mL, even after 1 h at pH 2. In all cases, phage were efficiently released from the microcapsules following a shift to a neutral pH (7.5), simulating passage to the duodenum. In summary, alginate-carrageenan-CaCO encapsulation is a promising approach for targeted intestinal delivery of genomically diverse bacteriophages.
在人类和牲畜中引发一系列具有相当大公共卫生和经济重要性的疾病。广泛使用抗菌药物，尤其是在集约化养殖的牲畜（如家禽和猪）中使用，可能会导致多重耐药菌株的增加。诸如噬菌体等替代疗法在用于减少牲畜肠道携带（某种病菌）时已显示出前景。然而，单胃动物胃肠道中遇到的消化酶和低pH值会显著降低噬菌体的活力并影响治疗效果。本研究采用了含和不含碳酸钙的藻酸盐-卡拉胶微胶囊，以保护一组基因组多样的五种噬菌体免受模拟胃肠道条件的影响。在暴露于pH < 3 10分钟后，未受保护的噬菌体均无法回收。藻酸盐-卡拉胶包封在暴露10分钟后提高了噬菌体在pH 2 - 2.5时的活力，但在pH 2 1小时后则没有。在配方中加入1%（/）碳酸钙进一步将噬菌体损失降低至<0.5 log PFU/mL，即使在pH 2 1小时后也是如此。在所有情况下，模拟进入十二指肠后，将pH值转变为中性（7.5）后，噬菌体均能有效地从微胶囊中释放出来。总之，藻酸盐-卡拉胶-碳酸钙包封是一种有前景的方法，可用于将基因组多样的噬菌体靶向递送至肠道。
