Analysis of Rancidity Mechanism of Armeniacae Semen Amarum During Storage / 中国实验方剂学杂志

Objective:To explore the mechanism of rancidity during storage by researching the changes of water content， relative permeability of cell membrane and rancidity levels of Armeniacae Semen Amarum in deterioration process. Method:Armeniacae Semen Amarum samples under different storage conditions were evaluated and classified by sensory assessors， and samples with different levels of rancidity were obtained. Water content was measured by toluene method， and water activity was obtained by water activity meter. Malondialdehyde （MDA） and relative conductivity were measured using thiobarbituric acid colorimetry and conductivity meter， respectively. The content of fatty oil was obtained by Soxhlet extraction. The acid value and peroxide value were measured in accordance with the general rules 0713 and 2303 of the 2020 edition of <italic>Chinese Pharmacopoeia</italic> （part Ⅳ）， respectively. Based on the above experimental data， chemometric methods （cluster analysis， principal component analysis） were selected to establish classification and discriminant models of Armeniacae Semen Amarum with different rancidity levels， in order to verify the accuracy of the classification results. Result:According to the results of sensory evaluation， Armeniacae Semen Amarum samples were divided into three classes， including no rancidity， slight rancidity and rancidity. Compared with the no rancid samples， the color of surface and cotyledon were deepened in rancid samples， and the oil was appeared on surface with rancid taste. The values of water content， water activity， MDA content and relative conductivity were all significantly increased in deterioration process （<italic>P</italic><0.01）. The content of fatty oil was significantly decreased with the occurrence of rancidness （<italic>P</italic><0.01）， while the acid value and peroxide value increased significantly （<italic>P</italic><0.01）. The results of cluster analysis and principal component analysis showed that the rancid samples could be distinguished from the no rancid and slightly rancid samples. Conclusion:The storage conditions under high temperature and high humidity can accelerate the rancidness of Armeniacae Semen Amarum， which is accompanied by the increase of internal water content， the increase of cell membrane permeability and the occurrence of fatty acid rancidity. It is suggested that Armeniacae Semen Amarum should be stored in low temperature， dry environment， as well as short storage time.

Change pattern and correlation analysis of macroscopic characteristics, active components and rancidness degrees of Armeniacae Semen Amarum in deterioration process / 中国中药杂志

To discuss the effect of deterioration on the quality of Armeniacae Semen Amarum by observing the changes of macroscopic characteristics, active components and rancidness degrees of Armeniacae Semen Amarum in deterioration process. The traditional macroscopic identification was used to observe, identify and classify the morphologic and organleptic characteristics of Armeniacae Semen Amarum. The contents of amygdalin and fatty oil(two representatives of active components) were detected by HPLC and general rule 0713 in Chinese Pharmacopoeia, respectively. Acid value and peroxide value of the samples were selected as the representative indices of different rancidness degrees, and the general rule 2303 was adopted as the method for quantitative analysis. Then principal component analysis(PCA), partial least square analysis discrimination analysis(PLS-DA) were further utilized to establish the discriminative models of samples with different rancidness degrees, and also to screen out the largest contribution factors. In sensory evaluation, Armeniacae Semen Amarum samples were divided into three groups: non-rancid, slightly-rancid, and noticeably-rancid. The color of seed coat, cotyledon and surface of noticeably-rancid samples was deepened, and the odor differed much from non-rancid samples. Average content of amygdalin and fatty oil in non-rancid samples was 4.12% and 67.77%, respectively, both meeting the requirements of Chinese Pharmacopoeia; and decreased to some extent in slightly-rancid samples. However, the content of amygdalin sharply dropped to 0.074% in noticeably-rancid samples. The acid value and peroxide value were increased significantly with the intensifying of the rancidness degree, from only 1.363 and 0.016 74 in non-rancid samples to 1.865 and 0.023 70 in slightly-rancid samples, even doubled in noticeably-rancid samples(2.167 and 0.033 82). The discriminative models established by PCA and PLS-DA could complete the task of distinguishing the non-rancid samples from noticeably-rancid ones. The contribution degree of amygdalin content as one of the input attributes of discriminative model was higher than 1. Rancidness affected the quality of Armeniacae Semen Amarum, resulting in appearance changes, decrease in content of active components, and increase in acid value and peroxide value. Obviously, noticeably-rancid samples were non-conforming to Chinese Pharmacopoeia and no longer suitable for medicinal use. Rancidness can significantly reduce the quality of Armeniacae Semen Amarum, and even could possibly produce toxicity, which should attach more attention.

Discrimination of Armeniacae Semen Amarum from different processed products and various rancidness degrees by electronic nose and support vector machine / 中国中药杂志

This study was aimed to develop a simple, rapid and reliable method for identifying Armeniacae Semen Amarum from different processed products and various rancidness degrees. The objective odor information of Armeniacae Semen Amarum was obtained by electronic nose. 105 batches of Armeniacae Semen Amarum samples were studied, including three processed products of Armeniacae Semen Amarum, fried Armeniacae Semen Amarum and peeled Armeniacae Semen Amarum, as well as the samples with various rancidness degrees: without rancidness, slight rancidness, and rancidness. The discriminant models of different processed products and rancidness degrees of Armeniacae Semen Amarum were established by Support Vector Machine(SVM), respectively, and the models were verified based on back estimation of blind samples. The results showed that there were differences in the characteristic response radar patterns of the sensor array of different processed products and the samples with different rancidness degrees. The initial identification rate was 95.90% and 92.45%, whilst validation recognition rate was 95.38% and 91.08% in SVM identification models. In conclusion, differentiation in odor of different processed and rancidness degree Armeniacae Semen Amarum was performed by the electronic nose technology, and different processed and rancidness degrees Armeniacae Semen Amarum were successfully discriminated by combining with SVM. This research provides ideas and methods for objective identification of odor of traditional Chinese medicine, conducive to the inheritance and development of traditional experience in odor identification.

Rancidness of Armeniacae Semen Amarum involving Bianzhuang Lunzhi / 中国中药杂志

This article aims to compare the qualities of Armeniacae Semen Amarum before and after rancidness, in order to study the rancidness of Armeniacae Semen Amarum. In the experiment, content of fatty oil, acid value and peroxide value were determined before and after rancidness,respectively. Meanwhile, HPLC, GC-MS were utilized to analyze laetrile and fatty acid components. Besides, colorimeter and e-nose were introduced to quantify and compare "color and odor". A correlation analysis was conducted on the above results. The results showed that color of post-rancidness Armeniacae Semen Amarum changed from yellow to brown, with sour and lower content of laetrile. On the contrary, acid and peroxide values increased significantly, with changes in fatty acid component. There was a considerable correlation between appearance characteristics and changes in internal quality. The "sensory analysis-quality identification system" can provide a certain scientific basis for prediction of the content of chemical components in traditional Chinese medicine, preliminary judgment of quality of traditional Chinese medicine and real-time quality monitoring, which offers us novel ideas and reference for storage principles of traditional Chinese medicines of "pre-event prediction, during-event intervention and post-event identification".