Interviews with Faculty Researchers

– Interview with Prof. Xia Xiaodong
Associate Professor, Department of Food Science and Nutrition

Microorganisms, though invisible to the naked eye, play a fundamental role in the global food system. Prof. Xia Xiaodong’s research focuses on these “invisible players” and their dual roles in enhancing food quality and posing risks to human health. His work integrates food safety with gut microbiome science, aiming to balance the control of harmful pathogens with the utilization of beneficial microbes.

Microbes are present throughout the food chain. Beneficial microorganisms support soil health, plant growth and fermentation processes that produce foods such as yogurt, cheese, and bread. In contrast, harmful microbes—including pathogens such as Salmonella and Escherichia coli—could cause food spoilage and illness, creating significant public health and economic challenges.

A central focus of Prof. Xia’s research is understanding how pathogens survive in complex environments. His laboratory investigates mechanisms such as biofilm formation, quorum sensing, and two-component regulatory systems, which enable microbial adaptation and resistance. Quorum sensing allows bacteria to coordinate collective behaviours through signalling molecules, while two-component systems translate environmental cues into gene regulation via sensor kinases and response regulators. Together, these processes form an integrated multi-component signalling framework that enhances bacterial survival and persistence.

Building on this understanding, his team develops innovative strategies to detect and control harmful microbes. Notably, they have developed a hydroxyl radical water-based decontamination method for pathogens in foods, enabling rapid and eco-friendly food sanitation.

In parallel, Prof. Xia explores the beneficial roles of microbes in human health. His research on Akkermansia muciniphila demonstrates its potential in alleviating hyperuricemia, highlighting the therapeutic value of gut microbiota and supporting the development of next-generation probiotics.

A key challenge in this field is balancing pathogen control with the preservation of beneficial microbes. Translating microbiome research into practical applications remains difficult due to the complexity of microbial identification and the need for both broad-spectrum and targeted interventions.

Despite these challenges, his work demonstrates strong real-world potential in improving food safety, advancing precision nutrition, and enabling microbiome-based therapies, contributing to safer, healthier and more sustainable food systems.
 

平衡安全與健康：微生物於食品系統中的角色

– 夏效東教授專訪
食品科學及營養學系副教授

微生物雖然不能被肉眼所見，卻在全球食品系統中扮演着舉足輕重的角色。夏效東教授致力研究微生物如何提升食品品質，同時又可能對人體健康構成風險。他結合了食品安全腸道微生物組科學，以在控制有害病原體與善用有益微生物之間取得平衡。

從農田到餐桌，微生物無處不在。有益微生物有助改善土壤健康、促進農作物生長，亦在乳酪、芝士及麵包等食品的發酵過程中發揮作用；相反，有害微生物，包括沙門氏菌及大腸桿菌等，則可能引致食物變質及疾病，對公共衛生及經濟帶來挑戰。

夏教授研究的一個重點，是了解病原體如何在複雜環境中存活。其團隊深入研究生物膜形成、群體感應及雙組分調控系統等機制，了解細菌如何適應環境並產生抗逆能力。當中，群體感應讓細菌透過訊號分子進行「溝通」，協調集體行為；雙組分系統則可將外界變化轉化為基因調控反應。這些機制共同構建出一個精密的訊號網絡，大大提升細菌的生存與持續能力。

對此，其團隊研發出創新的檢測管控技術，包括以羥基自由基水為基礎的食品去污法，能夠快速環保地消除食品中的病原體。

夏教授亦積極探索微生物對人體健康的正面作用。他發現黏蛋白阿克曼菌在緩解高尿酸血症方面具有潛力，突顯腸道微生物群的治療價值，並為新一代益生菌的發展開拓新方向。

然而，抑制有害微生物同時保留有益菌，仍是一大挑戰。由於微生物種類繁多且鑑定過程複雜，部分需要具針對性的應對策略，將之轉化為實際應用仍需進一步突破。

儘管如此，夏教授的研究在提升食品安全水平，及推動精準營養及微生物組醫療的發展已展現出巨大潛力，為建立更安全健康及可持續的食品系統注入了新動力。