Preventing outbreaks of foodborne pathogenic bacteria in edible sprouts via novel resistance-conferring seed treatments

摘要 这是欧洲最严重的食源性疫情之一，也是第二大“产滋贺毒素”大肠杆菌。杆菌 在全球范围内爆发，被追踪到E.大肠杆菌O 104：H4。它影响 16个国家的4，075名患者，包括908例溶血性尿毒综合征并发症 (HUS)50人死亡。在美国，豆芽被认为是58起食源性疫情的原因， 1996年和2017年，至少有1，953人患病，212人住院，5人死亡。又嫩又轻- 煮熟的可食用芽菜对通常起源于种子的食源性疾病的爆发具有高风险（vs. 典型的植物食源性疾病的加工条件发生）。虽然种子被少量污染， 人类肠道病原体，如沙门氏菌、大肠杆菌和单核细胞增生李斯特菌， 对最终的非发芽田间生长的作物几乎没有影响，发芽的明显温暖，潮湿的生长条件 有助于急剧放大这些病原体的生长到危险的水平。2 -5 包括苜蓿、绿豆和三叶草在内的豆芽在全球范围内继续增加，主要是由于它们的短 生长期长，容易获得，营养价值高，5与芽有关的食源性疾病的风险也是如此。 爆发FDA对越来越多的疫情表示严重关切。虽然FDA 建议将种子浸泡在20,000 ppm的次氯酸钙溶液中， 在发芽前立即进行批准的抗菌剂治疗，6种高浓度抗菌剂未能 彻底清除种子中的细菌，特别是那些已经渗入种子组织的细菌。根据 “到目前为止，还没有一种单一的治疗方法可以完全消除病原体。 引起食源性疾病而不影响发芽或产量的种子或芽。 为了防止食用豆芽中食源性致病菌的爆发，Ascribe Bioscience正在 开发基于天然微生物组衍生的 这种分子已被证明可以激活植物的天然防御， 在各种作物中，包括出苗前和出苗后，广泛的病原体。以确定可行性 建议的方法作为一种手段，有效地赋予保护芽免受人类肠道 第一阶段的开发将针对四个具体目标：1）开发一种有效的配方， 基于微生物组衍生的分子的种子处理，2）测试制剂对人类的功效， 3）在接种期间测试种子处理对人类肠道病原体的功效 4）测试另外的相关分子对人肝癌细胞生长抑制的功效， 肠道病原体第二阶段，我们将确定发芽种子处理配方，并进行广泛推广 其他类型的挑战。一旦充分发展，这种干预有可能减少萌芽- 相关的感染和爆发。

Abstract One of the most severe foodborne outbreaks in Europe, and the second-largest “Shiga toxin-producing” E. coli outbreak worldwide, was traced to E. coli O104: H4 in fresh fenugreek sprouts from a farm in Germany. It affected more than 4,075 individuals in 16 countries and included 908 cases complicated by hemolytic uremic syndrome (HUS) and 50 deaths. In the U.S., sprouts were implicated as the cause of 58 foodborne outbreaks between 1996 and 2017, encompassing at least 1,953 illnesses, 212 hospitalizations, and 5 deaths. Raw and lightly- cooked edible sprouts pose high risk for outbreaks of foodborne illness which typically originate in the seeds (vs. processing condition genesis of typical plant foodborne illnesses). While seeds contaminated with small amounts of human enteric pathogens, such as Salmonella enterica, Escherichia coli and Listeria monocytogenes have little to no impact on final non-sprout field grown crops, the distinct warm, humid growing conditions of sprouts serve to dramatically amplify growth of these pathogens to dangerous levels.2-5 As the consumption of edible sprouts, including alfalfa, mung bean and clover continues to increase worldwide, largely due to their short growing period, easy availability and high nutritive value,5 so too does the risk of sprout‐related foodborne illness outbreak. The FDA has expressed serious concern over the increasing number of outbreaks. While the FDA recommends soaking the seeds in 20,000 ppm solution of calcium hypochlorite, as well as applying a least one approved antimicrobial treatment immediately before sprouting,6 high concentrations of antimicrobials fail to completely eliminate bacteria from seed, particularly those that have infiltrated seed tissue. According to the agency, “There is no single treatment so far that has been shown to completely eliminate pathogens on seeds or sprouts that cause foodborne illness without affecting germination or yield.” To prevent outbreaks of foodborne pathogenic bacteria in edible sprouts, Ascribe Bioscience is developing novel resistance-conferring seed treatments based on a natural, microbiome-derived molecule that has been shown to activate a plant's natural defenses to provide protection against a broad range of pathogens in a variety of crops, both pre- and post-emergence. To establish the feasibility of the proposed approach as a means to effectively confer protection to sprouts against human enteric pathogens, Phase I development will target four specific aims: 1) Develop an efficacious formulation for sprout seed treatment based on the microbiome-derived molecule, 2) Test the efficacy of the formulation against human enteric pathogens, 3) Test the efficacy of the seed treatment against human enteric pathogens during seed production and after harvest, 4) Test the efficacy of additional related molecules on growth inhibition of human enteric pathogens. In Phase II, we will finalize the sprout seed treatment formulation and conduct broad spread challenges on other types of spouts. Once fully developed, this intervention has the potential to reduce sprout- related infections and outbreaks.