Effects of Different Storage Methods and Storage Time on the Quality of Codonopsis pilosula

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1. Shanxi Zhendong Genuine Medicinal Medicine Development Co., Ltd., Changzhi 047100, China; 2. Agricultural and Rural Bureau of Shangdang District in Changzhi City, Changzhi 047100, China; 3. Jun He & Baian Lily Storage Technology (Beijing) Co., Ltd., Beijing 100020, China; 4. Shanxi Zhendong Pharmaceutical Co., Ltd., Changzhi 047100, China

Abstract [Objectives] To study the effects of different storage methods and storage time on the quality of Codonopsis pilosula. [Methods] Experiment was performed by setting three different storage methods and times. [Results] When stored for 12 months, the extract content in the natural storage, conventional sealing, and controlled atmosphere storage was slightly lower than 77.32% before storage, and decreased by 2.82%, 3.62%, and 1.71%, respectively. When stored for 18 months, the extract content was 74.14%, 73.21%, and 72.08%, decreased by 4.11%, 5.31%, and 6.78%, respectively compared with that before storage, all of which met the specified content in Chinese Pharmacopoeia. [Conclusions] The three storage times had significant effects on moisture and extract content of C. pilosula, but had no significant effects on atractylenolide III. With the extension of storage time, the moisture, extract, and content declined, so the storage time theoretically should not exceed 12 months.

Key words Codonopsis pilosula, Storage methods, Quality, Effects

1 Introduction

Codonopsispilosula(Franch.)Nannf.) (genusCodonopsis, family Campanulaceae) is a traditional tonic medicine commonly used in China. In ancient time,C.pilosulaproduced in Shanxi was considered as top grade. It has functions of reinforcing the middle and benefiting qi, and strengthening spleen and tonifying lung.C.pilosulahas functions of enhancing immunity, dilating blood vessels, lowering blood pressure, improving microcirculation, and enhancing hematopoietic function. In addition,C.pilosulahas functions of lifting the decline of leucocyte resulted from chemotherapy and radiotherapy[1-3].

C.pilosulacontains more nutrients such as starch and sugars, and it is extremely susceptible to damage by worms, mildew, stickiness, and discoloration during the actual storage. At present,C.pilosulastorage still mainly uses traditional sulfur and aluminum phosphide fumigation to prevent mildew and worm damage, and some large enterprises or individuals use low-temperature cold storage to keepC.pilosula[4-5]. The sulfur and aluminum phosphide fumigation method is low in cost and simple, but it often causes excessive residues of harmful substances such as SO2in the medicinal materials, which greatly destroys the intrinsic quality of the medicinal materials, greatly reduces the efficacy, and even generates drug-induced adverse reactions, and seriously harm people’s health. Low-temperature cold storage can effectively prevent worm damage and mildew, and can better maintain the quality of medicinal materials, but cold storage is expensive, and the cost of use and maintenance is high, so it is not favorable for popularization. Besides, the quality of medicinal materials inside and outside will change sharply after medicinal materials leave warehouse[6-8].

In view of these, we performed storage experiment onC.pilosulastorage through a green and environment-friendly air regulating agent, so as to establish a safe and environmentalC.pilosulastorage technical system with simple operation and comprehensive maintenance and low cost.

2 Materials and methods

2.1ExperimentdesignIn this experiment,C.pilosuladecoction pieces were used as test materials, which were divided into three treatments: natural storage (C1), conventional sealing (C2) and controlled atmosphere storage (C3). Under each treatment, there are three different storage periods: 6 months (S1), 12 months (S2), and 18 months (S3). The experiment adopted split plot design, the storage method was the primary plot, and the storage time was the secondary plot, forming a total of 9 treatments, each treatment repeated three times. The specific treatment and number are indicated in Table 1. The storage time of 6 months was from June 2015 to December 2015; the storage time of 12 months was from June 2015 to June 2016; the storage time of 18 months was from June 2015 to December 2016. The specific experimental design is as follows:

Randomly selected 3.5 kg ofC.pilosulamedicinal material with normal color, no insect mold, moisture < 16%, cut them with a slicer into about 0.5 cm thick slices with relatively uniform thickness, and then fully and evenly mixed. Then, randomly weighed 3 kg ofC.pilosulaslices, evenly divided into 10 pieces, each piece 0.3 kg; randomly selected 3 pieces to conduct controlled atmosphere storage experiment (added the air regulating agent produced by Jun He & Baian Storage Technology (Beijing) Co., Ltd.), selected 3 pieces to conduct conventional sealing, and 3 pieces for natural storage treatment (piercing holes after conventional sealing), and the remaining one piece used as the reference.

2.2AnalysisofappearancechangesDuring the controlled atmosphere storage experiment, it is necessary to observe the changes in discoloration, insect damage, mold, and oil weeping phenomenon ofC.pilosula. In non-rainy seasons, it is generally enough to observe one time with the naked eye every 30 d; in the rainy seasons, it is usually observed once every 7 d, and make a detailed record of the time, type and degree of first deterioration ofC.pilosula, and use the same digital camera to take photos for storage. The degree of deterioration is roughly divided into four levels: mild, general, severe, and very severe. Specifically, individual cases are recorded as mild level, deterioration of less than 1/3 cases are recorded as general level, and 1/2 cases are recorded as severe level, and more than 1/2 cases are deemed as very severe level.

2.3AnalysisofchangesinmoistureandextractsThe moisture content and extract content ofC.pilosulain controlled atmosphere, conventional sealing, and natural storage treatments were measured separately by drying method and alcohol-soluble extract determination method. The effects of each treatment and storage methods on the main substance components ofC.pilosulawere compared before and after storage.

2.4AnalysisofchangesinmainactivecomponentsThe effects ofC.pilosulaatractylenolide III content before and after controlled atmosphere storage, conventional seal, and natural storage treatment were measured by high performance liquid chromatography (HPLC), and the effects of different treatments and storage methods on the main active components ofC.pilosulawere compared.

2.5DataanalysisThe analysis was performed with the aid of Excel 2016 and SPSS 19.0. The analysis of variance showed that all were at the 0.05 level, and theLSDmethod was used.

3 Results and analysis

3.1DynamicchangesintemperatureFrom Fig.1, it can be seen that in January 2015 in Changzhi of Shanxi Province, the temperature was the lowest, with an average monthly minimum temperature of -5.80 ℃ and an average monthly maximum temperature of 4.73 ℃; in February, it began to gradually rise, with the highest temperature in July and an average monthly maximum temperature of 28.5 ℃, the average monthly minimum temperature of 17.43 ℃; in August, it began to decline, and it was the lowest in December (the same as the average monthly maximum temperature in January), the average monthly maximum temperature of 4.73 ℃, and the average monthly minimum temperature of -5.63 ℃. In January 2016, the temperature was the lowest, with an average monthly minimum temperature of -9.57 ℃ and an average monthly maximum temperature of 1.77 ℃; in February, it began to gradually rise, with the highest temperature in July and an average monthly maximum temperature of 27.47 ℃, the average monthly minimum temperature of 18.27 ℃; in August, it began to decline, and it was the lowest in December, the average monthly maximum temperature of 6.10 ℃, and the average monthly minimum temperature of -3.50 ℃. Compared with 2015, the winter temperature in 2016 was lower, with the monthly minimum temperature in January being 3.77 ℃, and the summer temperature was higher, and the average monthly maximum temperature in July was 1.03 ℃ higher.

Fig.1Dynamicchangesoftemperaturein2015and2016

3.3AppearanceofsamplesbeforeandafterstorageDuring June 2015 and December 2016, the changes in appearance of the samples before and after storage ofC.pilosulaare shown in Table 1.

3.3EffectsofdifferentstoragemethodsonmoistureandextractcontentFrom Fig.2, it can be seen that in the three treatment methods, the changes of moisture ofC.pilosulaare slightly different. The moisture ofC.pilosulain natural storage increased sequentially with the increase of time. By 18 months of storage, the moisture reached a maximum of 12.2%, which was 16.06% higher than that of 6 months. By comparison, the moisture ofC.pilosulain conventional sealing and controlled atmosphere first increased and then decreased with the increase of time; the moisture of conventional sealing increased from 10.71% to 12% and

Table1ComparisonofappearanceofsamplesofCodonopsispilosulabeforeandafterstorage

TreatmentBefore storage After storageEffects of insect andmildew prevention∥%DeteriorationdegreeC1S1No discoloration,insect damage, mil-Insect and rat damage occurs in some medicinal materials after storage of 4-6 months90MildC2S1dew, or oil weepingNo discoloration, insect damage, mildew, or oil weeping100N/AC3S1No discoloration, insect damage, mildew, or oil weeping100N/AC1S2No discoloration, insect damage, mildew, or oil weeping95MildC2S2No discoloration, insect damage, mildew, or oil weeping100N/AC3S2No discoloration, insect damage, mildew, or oil weeping100N/AC1S3No discoloration, insect damage, mildew, or oil weeping100N/AC2S3No discoloration, insect damage, mildew, or oil weeping100N/AC3S3No discoloration, insect damage, mildew, or oil weeping100N/A

Note: the degree of deterioration is roughly divided into four levels: mild, general, severe, and very severe.

decreased to 11.4%, which was 6.05% higher than that of 6 months. The moisture of controlled atmosphere increased from 10.78% to 12.08% and decreased to 11.72%, which was 8.02% higher than that of 6 months. The moisture of all the three storage methods increased compared with 10.22% before storage. Natural storage, conventional sealing, and controlled atmosphere storage increased by 16.23%, 10.35%, and 12.79%, respectively, but all met the stipulation ofChinesePharmacopoeia(lower than 16%).

Note: C1: natural storage, C2: conventional sealing, C3: controlled atmosphere.

Fig.2MoistureofCodonopsispilosulabeforeandafterstorage

From Fig.3, it can be seen that with the increase of storage time, the extract content reached the maximum when the storage time of all three treatment methods was 12 months, and finally decreased. When the storage time was 12 months, the extract content of natural storage, conventional sealing, and controlled atmosphere storage methods was 75.14%, 74.52%, and 76.00%, respectively, but the extract of all three storage methods was lower than 77.32% before storage, being 2.82%, 3.62%, 1.71%, respectively, and the decline of controlled atmosphere was the smallest. When the storage time was 18 months, the extract content was 74.14%, 73.21%, and 72.08%, decreased by 4.11%, 5.31%, and 6.78%, respectively compared with that before storage, all of which met the specified content ofChinesePharmacopoeia(≥55%).

3.4EffectsofdifferentstoragemethodsonmainactivecomponentsAccording to Fig.4, forC.pilosulain natural storage, the content of atractylone III decreased with the extension of time,

Note: C1: natural storage, C2: conventional sealing, C3: controlled atmosphere.

Fig.3ExtractcontentofCodonopsispilosulabeforeandafterstorage

it was 0.76‰ at 6 months, 0.65‰ at 12 months, and 0.6‰ at 18 months, all were lower than 0.78‰ before storage. By comparison, the content of atractylone III inC.pilosulain conventional sealing and controlled atmosphere first increased then decreased with the extension of time. After storage for 12 months, the content of atractylone III was 0.71‰ and 0.7‰, both were lower than that before storage, the maximum value was 0.71‰; after storage for 18 months, the content of atractylone III was 0.65‰.

Note: C1: natural storage, C2: conventional sealing, C3: controlled atmosphere.

Fig.4ContentofatractyloneIIIinCodonopsispilosulabeforeandafterstorage

3.5Effectsofdifferentstoragemethodsonmoistureandextract,andatractyloneIIIFrom Table 2, it can be seen that there is no significant difference in moisture and atractylone III among different storage methods; in natural storage, the extract ofC.pilosulawas 75.23%, which was significantly higher than that of the conventional sealing and controlled atmosphere treatment. In nature storage, the atractylone III inC.pilosulawas 6.66‰, which was significantly higher than that of the conventional sealing and controlled atmosphere treatment.

Table2Effectsofdifferentstoragemethodsonmoisture,extract,andatractyloneIIIinCodonopsispilosula

TreatmentMoisture∥%Extract∥%Atractylone III∥‰C111.31 a75.23 a6.66 aC211.37 a73.62 b6.54 aC311.52 a73.33 b6.49 a

Note: different small letters denote significant differences in the moisture, extract, and atractylone III between different storage methods (P<0.05).

3.6Effectsofdifferentstoragetimeonmoistureandextract,andatractyloneIIIAccording to Table 3, the difference in moisture at different storage time was significant. The moisture at 6 months of storage was 10.58%, which was significantly lower than that at 12 months and 18 months. The extract at 12 months of storage was 75.22%, which was significantly higher than that at 6 months and 18 months; there was no significant difference in atractylone III between different treatments.

Table3Effectsofdifferentstoragetimeonmoisture,extract,andatractyloneIIIinCodonopsispilosula

TreatmentMoisture∥%Extract∥%Atractylone III∥‰S110.58 a73.81 b6.66 aS211.86 b75.22 a6.84 aS311.77 c73.15 b6.32 a

Note: different small letters denote significant differences in the moisture, extract, and atractylone III between different storage time (P<0.05).

3.7Correlationbetweenstoragemethodsandmoisture,extract,andatractyloneIIIAccording to Table 4, there was significant correlation between the storage method and the moisture, extract, and atractylone III. Therefore, finding a scientific and reasonable storage method is of great significance for the content and quality ofC.pilosula.

Table4Correlationbetweenstoragemethodsandmoisture,extract,andatractyloneIII

MoistureExtractAtractylone IIIMoisture1Extract0.231Atractylone III0.120.931Storage method0.960.940.95

4 Discussions

There are many factors that affect the quality of traditional Chinese medicine decoction pieces. In the first place, it is necessary to establish a scientific, objective, and operable processing standard and quality standard, and establish a sound and standardized quality standard system for Chinese medicine decoction pieces. More important, we must overcome the influence of external factors during the storage of decoction pieces to the greatest extent. In actual work, it is necessary to adopt various scientific storage methods according to the properties, seasonal changes and decoction piece stocks of traditional Chinese medicine, and to introduce advanced concepts, methods and technologies of modern warehouse management into traditional Chinese medicine storage, such as controlled atmosphere maintenance technology, computer technology, Co60 radiation technology,etc. During the storage of decoction pieces, modern methods such as computer technology, biotechnology, and traditional Chinese medicine fingerprinting technology can be adopted to monitor the quality of decoction pieces and improve their clinical efficacy to meet the medical requirements and the needs of formulated preparations to ensure the safety and effectiveness of clinical application of drugs[9].

Controlled atmosphere packaging (CAP) is also called modified atmosphere packaging (MAP). It replaces the active gas (such as oxygen, ethylene,etc.) inside the packaging unit with inactive gas, such as nitrogen, CO2, or a mixture of them, so that the medicinal materials can be kept fresh in the modified atmosphere. In order to ensure the preservation effect of gas replacement packaging, different gas compositions should be used according to the storage requirements of different medicinal materials, and it is required to consider the airtightness and sealing adaptability of packaging materials. Some studies have shown that whenAngelicasinensisis stored under CO2, at 5 ℃, and 15% moisture, it can be ensured that the effective content of ferulic acid will not change significantly for a long time[10].

This study is expected to make the tuber type Chinese medicinal materials highly effective, prevent deterioration, and provide a basic guarantee for the source materials of traditional Chinese medicine, so it will have a far-reaching significance, and the method is practical and feasible.

5 Conclusions

The effects of natural storage, conventional sealing, and controlled atmosphere storage methods on moisture and atractylone III are not significant, but are significant on the extract content. In natural storage, the extract content ofC.pilosulais significantly higher than that of conventional sealing and controlled atmosphere storage methods. With the extension of storage time, the extract content reaches the maximum when the storage time is 12 months. The extract content ofC.pilosulain natural storage, conventional sealing, and controlled atmosphere is slightly lower than 77.32% before the storage, by 2.82%, 3.62%, and 1.71%, respectively, and the decline of controlled atmosphere is the smallest. When the storage time is 18 months, the extract content declined by 4.11%, 5.31%, and 6.78%, respectively compared with that before storage, but all of which met the specified content ofChinesePharmacopoeia(≥55%). In conclusion, the three storage times have significant effects on moisture and extract content ofC.pilosula, but have no significant effects on atractylenolide

III. Besides, the moisture ofC.pilosulain nature storage is significantly higher than that of conventional sealing and controlled atmosphere; the extract content ofC.pilosulain conventional sealing is significantly higher than that of controlled atmosphere and natural storage. With the extension of storage time, the moisture, extract and atractylone III decline slightly, so the storage time should not exceed 12 months.