Tong Shi-Ruo, Lee Ting-Hun, Cheong Soon-Keng, Lim Yang-Mooi
Department of Pre-clinical Sciences, Faculty of Medicine and Health Sciences, Universiti Tunku Abdul Rahman, Jalan Sungai Long, Bandar Sungai Long, 43000, Kajang, Cheras, Selangor, Malaysia.
Department of Bioprocess and Polymer Engineering, School of Chemical and Energy Engineering, Universiti Teknologi Malaysia, 81310, Johor Bahru, Johor, Malaysia.
Vet World. 2020 Feb;13(2):304-316. doi: 10.14202/vetworld.2020.304-316. Epub 2020 Feb 17.
Edible bird's nest (EBN) is the nutrient-rich salivary bioproduct produced by swiftlets in Southeast Asia. Currently, researchers are exploring the therapeutic effects of EBN, such as cell growth promotion, antioxidant content, antiviral effects, bone strengthening, eyes care, and neuroprotection bioactivities. The therapeutic effects of EBN have been studied through different extraction methods but the metabolites profile of the EBN in each extract has not yet been elucidated. This study aimed to profile the water-soluble metabolites of EBN prepared in different extraction methods. Subsequently, an extraction method will be selected as an ideal extraction method for untargeted metabolite profiling on the water-soluble metabolites in EBN.
In this study, water-soluble metabolites of EBN extracted by the four extraction methods were subjected to metabolite profiling through liquid chromatography-mass spectrometry (LC-MS). The extraction methods were acid extraction(ABN), pancreatic extraction (EzBN), eHMG extraction, and spray drying of HMG extraction (pHMG). The metabolite profiles, such as the number of metabolites and their identities in each extraction method, were evaluated through LC-MS analysis.
The identity of metabolites present in the four extraction methods is inconsistent. Based on LC-MS analysis, only one and six metabolites were extracted differently through EzBN and ABN, respectively, in the first pre-screening. Through the second LC-MS screening on pHMG and eHMG extraction methods, eHMG was selected as an ideal extraction method due to the highest numbers of water-soluble metabolites with an amount of 193 was detected. Besides, eHMG extraction method was able to extract sialic acid and a high percentage of secondary metabolites.
This study suggests that eHMG is the ideal extraction method for extracting higher number of water-soluble metabolites from EBN and could be further developed as an extraction method for industry application. In addition, this study also has identified the types of primary and secondary metabolites present in EBN.
食用燕窝（EBN）是东南亚金丝燕分泌的富含营养的唾液生物制品。目前，研究人员正在探索食用燕窝的治疗效果，如促进细胞生长、抗氧化成分、抗病毒作用、增强骨骼、眼部护理和神经保护生物活性。已经通过不同的提取方法研究了食用燕窝的治疗效果，但每种提取物中食用燕窝的代谢物谱尚未阐明。本研究旨在分析不同提取方法制备的食用燕窝的水溶性代谢物。随后，将选择一种提取方法作为对食用燕窝中水溶性代谢物进行非靶向代谢物分析的理想提取方法。
在本研究中，通过液相色谱-质谱联用（LC-MS）对采用四种提取方法提取的食用燕窝的水溶性代谢物进行代谢物分析。提取方法包括酸提取（ABN）、胰酶提取（EzBN）、eHMG提取以及HMG提取的喷雾干燥法（pHMG）。通过LC-MS分析评估每种提取方法中的代谢物谱，如代谢物数量及其特性。
四种提取方法中存在的代谢物特性不一致。基于LC-MS分析，在第一次预筛选中，通过EzBN和ABN分别仅不同地提取出一种和六种代谢物。通过对pHMG和eHMG提取方法的第二次LC-MS筛选，由于检测到的水溶性代谢物数量最多，为193种，eHMG被选为理想的提取方法。此外，eHMG提取方法能够提取唾液酸和高比例的次生代谢物。
本研究表明，eHMG是从食用燕窝中提取更多水溶性代谢物的理想提取方法，可进一步开发为工业应用的提取方法。此外，本研究还确定了食用燕窝中存在的初级和次级代谢物类型。
