Chinese team research finds new lactam coffee diterpene

Yunnan Coffee relies on a unique plateau climate and rich and diverse ecology, forming a unique quality of rich accumulation of substances, rich taste without bitterness, fragrant but not strong, oily, fruity and other unique qualities, becoming a must-have raw material for Nestlé and other internationally renowned companies First, make Yunnan an important global production base for small grain coffee. The Yunnan Provincial Party Committee and Provincial Government have listed the coffee industry as one of the eight agricultural industries with plateau characteristics. The coffee industry also plays a very important role in implementing Yunnan's strategic goal of creating a world-class "green food brand."
 
All along, Qiu Minghua's research team at the Kunming Institute of Chinese Academy of Sciences has been studying the material basis and quality formation mechanism of Yunnan coffee's unique quality. In recent years, a series of biologically active inclusions have been discovered from Yunnan coffee, such as new coffee diterpene glycoside compounds, new coffee diterpene lactones, and dammarane-type triterpenes, which greatly enriched Yunnan coffee "inclusions Accumulate rich" diversity quality.
 
The team also reviewed the research progress in the synthetic pathways and biological activity of caffeine, chlorogenic acid, trigonelline, melanin, acrylamide, and diterpene in coffee, and reported that the coffee roasting degree and social concern in Yunnan are very high The trend of the content of acrylamide.
 
Recently, Qiu Minghua's research team discovered a series of coffee diterpene lactam-type compound Cafemide A-G from the cooked beans of Yunnan Coffee, and divided them into I-III subtypes according to the chemical structural characteristics. The molecular network technology based on LC-MS/MS was applied to the trace discovery of trace lactam coffee diterpenes, and 7 novel coffee diterpene II subtype lactam compounds were quickly identified and formed by multi-stage mass spectrometry fragments The derivation verified its structure.
 
LC-MS/MS analysis also proved that in addition to the presence of coffee diterpene I-III subtype lactam compounds, there are many other subtypes of nitrogen-containing diterpenoid compounds in roasted beans in Yunnan coffee. Studies on biological activity show that: Cafemetes A-C, E, and G exhibit good α-glucosidase inhibitory effect, and their activity is better than that of acarbose, a first-line clinical treatment drug for diabetes, and has the potential function of controlling blood sugar.
 
This is the first discovery of the nitrogen-containing coffee diterpene structure in coffee chemistry research, which once again interprets the unique quality of Yunnan coffee's rich accumulation of contents. The results were published in the Journal of Agriculture and Food Chemistry.
 
Unripe coffee beans are the main kind of defective beans, which will cause the bad astringency of coffee. Once they are mixed into commercial beans, it is difficult to distinguish them, thus affecting the overall quality of coffee.
 
Therefore, the research team of Qiu Minghua used the method of 1H NMR-based chemometric analysis to investigate and track the markers that affect coffee maturity, and established a partial least squares discriminant analysis (PLS-DA) to quickly identify coffee immature beans. ) Distinguish the model, in-depth study of the accumulation of maturity markers in fresh fruits of different degrees of maturity, combined with coffee cup measurement, to clarify the relationship between the accumulation of maturity markers and coffee quality, this is to understand the quality of Yunnan coffee The formation mechanism to control the best time for picking fresh coffee fruits and to ensure the high quality of Yunnan coffee provides an important theoretical basis. The research results were published in "International Food Research".