Analysis Of Microbial Pollution In Fructus Aurantii

Objective The microbial load level of Fructus aurantii was investigated,the bacterial strains were isolated and identified,and the potential harm of the contaminated microorganisms was evaluated.Secondly,the bacteria in fructus aurantii,medicinal materials,decoction pieces and processed decoction pieces were examined by microbial limit test and the strains were isolated and identified,and the identification results were traced.The changes of microbial load level and bacterial species in Fructus aurantii before and after water boiling and alcohol precipitation were analyzed.The effects of temperature and water activity on the microbial load level of Fructus aurantii were investigated.Finally,measures were proposed to solve the problem of microbial contamination by scientific pre-treatment of medicinal materials from the source according to the pollution source,improve the processing environmental conditions to avoid exogenous pollution,and prevent microbial reproduction during storage and transportation by optimizing the packaging materials,which provided a reference for the directional and purposeful control of the microbial load level of traditional Chinese medicine production and processing enterprises.Method and ResultA total of 36 batches of Fructus aurantii,42 batches of decoction pieces and 3batches of fruit were collected in this study.The producing area was mainly Jiangxi Province.According to Chinese Pharmacopoeia General Rule 1109,microbial limit test for Chinese herbal decoction pieces was performed on all collected samples,and SPSS software was used for statistical analysis.There were significant(P<0.05)or extremely significant(P<0.01)differences in the total number of aerobic bacteria,mold,yeast and heat-resistant bacteria in Fructus aurantii products from different habitats and different processing technologies,which indicated that processing technology and climate environment were independent factors affecting the microbial load in Fructus aurantii.Among all the samples,there were 11 batches of medicinal materials and 4 batches of ready-to-drink pieces.The results of microbial limit test exceeded the standard of direct oral and oral ready-to-drink pieces in four parts of Chinese Pharmacopoeia(2020 edition),indicating quality risks.In this study,470 strains of bacteria and 91 strains of fungi were identified by traditional biochemical identification and molecular biological methods.According to the identification results,the bacteria could be classified into 17 genera and 60 species.The fungi were classified into 21 genera and 37 species.Bacillus and other heat-resistant bacteria were the absolute dominant bacteria in Fructus aurantii,Aspergillus had the highest fungal isolation ratio.The detection of pathogenic bacteria,conditioned pathogenic bacteria,heat-resistant bacteria and toxigenic fungi suggested that the microorganisms in Fructus aurantii would pose a serious threat to the safety of drug patients and seriously affect the quality and safety of drugs.By analyzing the identification results of bacteria isolated from samples in different processing stages of Fructus aurantii,it was found that in the whole processing process from fresh fruit to Fructus aurantii stir-fried with bran,the microbial load types of products in different stages were reduced.Under the selective pressure of dehydration and heat treatment,such as drying and roasting,bacillus type heat-resistant bacteria are enriched,and there are new microbial contamination in the process of processing.By using Bio Numerics3.0database software and other tractive analysis,it was found that the homology of isolated bacteria at different processing stages was more than 90%,and some even reached 100%.Most of the bacteria isolated from decoction pieces could cluster with the bacteria isolated from fruits or medicinal materials,indicating that raw materials are an important source of microbial pollution in Fructus aurantii.It was found through the simulation process of water extraction and alcohol precipitation that the number and types of microorganisms obtained after water extraction and alcohol precipitation were very small,and even could completely kill mold and yeast,indicating that water extraction and alcohol precipitation can effectively reduce the microbial load in traditional Chinese medicine preparations.However,conditional pathogenic bacteria and heat-resistant bacteria were still detected,indicating the risk of microbial contamination.By simulating the microbial load changes in Fructus aurantii under different water activity storage conditions,it was found that the number of aerobic bacteria,mold and yeast did not change significantly under lower water activity storage conditions.The water activity of storage environment had a great impact on the microbial load in Aurantii at 0.902 and 0.973.After 1 to 2 months of storage,with the increase of sample water activity,the number of microorganisms showed a typical S-shaped curve growth,which suggested that we should focus on the moisture permeability and sealing property when selecting pharmaceutical packaging materials.Conclusion In this study,we found that the microbial pollution in Fructus aurantii is not optimistic.Compared with the methods such as irradiation sterilization with cobalt-60,which may cause the chemical composition changes of medicinal materials and radiation residues,According to the source of pollution,the problem of microbial pollution can be solved by scientific pre-treatment of medicinal materials from the source,improvement of processing environmental conditions to avoid exogenous pollution,and prevention of microbial propagation in the process of storage and transportation by optimizing the packaging materials,which can help the production and processing enterprises of traditional Chinese medicine have directional and purposeful control of the microbial load level of traditional Chinese medicine,and improve the quality of Chinese traditional Chinese medicine products.So that it can step over the threshold of international standards,enter the international stage with new quality,and show the advantages of Chinese genuine medicinal materials in international competition.