Identification and Quantification of Carbohydrates, Amino Acids, and Protein in Gazo (Oak Manna)

Abstract

Background: Gazo, or oak manna, is a natural exudate of Quercus species formed through insect activity. Although traditionally valued as a sweetener and folk remedy, its biochemical composition and health potential remain poorly defined. Objectives: This study aimed to characterize the biochemical properties of Gazo, focusing on its carbohydrate, amino acid, and protein content, to provide a scientific foundation for its nutritional and medicinal value. Methods: Gazo samples were collected from Quercus infectoria trees in the Kurdistan province of Iran. Qualitative biochemical tests were conducted to identify the presence of carbohydrates, amino acids, and proteins. Quantitative analyses were performed using LC-MS/MS for sugars, HPLC for amino acids, and the Kjeldahl method for total protein content. Results: Qualitative assays confirmed the presence of monosaccharides, disaccharides, and various amino acids, but not starch or intact proteins. Quantitatively, sucrose (11.79%), maltose (5.98%), and glucose (2.95%) were the dominant carbohydrates. Leucine, isoleucine, valine, and threonine were the most abundant amino acids, while total protein content was relatively low (2.18% w/w). Conclusions: Gazo is rich in digestible sugars and essential amino acids, particularly branched-chain amino acids (BCAAs), but contains minimal protein and no complex carbohydrates. These findings support its traditional use and suggest its potential in nutritional, functional food, and health-related applications. Further research is needed to explore its bioactive compounds and therapeutic properties.