Whole-process optimization for industrial production of glucosamine sulfate sodium chloride based on QbD concept

The double salt of glucosamine sulfate sodium chloride(glucosamine-SP) is an important pharmaceuticals ingredient for healing osteoarthritis. However, the study about its industrial production is rarely documented, let alone the optimization over the whole process to produce glucosamine-SP using glucosamine hydrochloride and anhydrous sodium sulfate as synthetic raw materials. In order to improve the production efficiency, this study screened the process parameters based on the concept of quality by design(QbD), optimized 13 operational parameters related to reaction and separation in the process, and finally proposed the mixed dropping process. The reaction conditions for the preparation of glucosamineSP were found as follows: the molar ratio of anhydrous sodium sulfate to glucosamine hydrochloride is 0.42, the mass ratio of water to glucosamine hydrochloride is is 2.0, the reaction temperature is 50 ℃ and the reaction time is 1 h. Through step-by-step scaling up following QbD, the mixed dropping process was successfully applied to achieve a trial production of 200 kg products satisfying national quality standards.In all, the results of this study have high technical value and guiding significance for the industrial mass production of glucosamine-SP.

Microfossil evidence of rice cultivation on the Southeast China Coast 7500 years ago

Located on the southeast coast of China,Fujian is an important junction for the spread and migration of agriculture and populations from mainland Asia to Taiwan and the Island Southeast Asia.Research on the emergence of agriculture and its relationship with the regional environmental context is key to understanding the evolution of ancient human-land interactions in the coastal zone of China.This paper presents a detailed microfossil analysis of the Dapingding site,which is located in the lower reaches of the Min River on the southeast coast of China.We found a large number of phytoliths produced in rice stems and leaves from the cultural layers of this site,dated to 7,500 cal.a BP.In addition,we found rice husk impressions and rice phytoliths in the pottery sherds of these cultural layers.Among these phytoliths,rice bulliform phytoliths with≥9 fish-scale patterns indicating the degree of rice domestication,accounted for 44%.This percentage is much higher than the established standard for wild rice bulliform phytoliths with fish-scale patterns,suggesting that rice cultivation had already occurred on the southeast coast of China approximately 7,500 years ago.Subsequently,the starting time of agricultural activity on the southeast coast of China was pushed from 5,000 to 7,500 years ago.Comparing the regional history of sea level and coastline changes in the early to mid-Holocene,we suggest that the emergence of early rice cultivation in Southeast China was associated with high sea levels in the midHolocene and the last transgression in the Fuzhou Basin.The’Fuzhou Bay’,formed by the retreating coastline and transgression driven by high sea levels,may have provided a sea channel for the southward movement of northern rice farmers.