Rectification extraction of Chinese herbs’ volatile oils and comparison with conventional steam distillation

Drying of Chinese medicine residues (CMR) by hot air for potential utilization as renewable fuels: drying behaviors, effective moisture diffusivity, and pollutant emissions

High moisture in Chinese medicine residues (CMR) can decrease the energy efficiency of thermochemical conversion, which necessitates the pre-drying. Owing to the complex constituents and decoction, CMR may possess distinct drying characteristics. It is necessary to understand its drying behaviors, effective moisture diffusivity, and pollutant emissions for future design and optimization of an industrial-level dryer. In this study, the drying of four types of typical CMR in hot nitrogen was performed. Their condensate and exhaust gas were collected and characterized. The results indicated that their drying process was dominated by internal moisture transport mechanism with a long falling rate stage. Drying temperature influenced their drying process more greatly than N2 velocity did. Residual sum of squares, root mean square error, and coefficient of determination indicated that Weibull model demonstrated their drying process best. Their effective moisture diffusivity was in the range of 1.224 × 10-8 to 4.868 × 10-8 m2/s, while their drying activation energy ranged from 16.93 to 30.39 kJ/mol. The acidic condensate had high chemical oxygen demand and total nitrogen concentration and yet low total phosphorus concentration. The concentration of total volatile organic compounds, non-methane hydrocarbons, H2S, and NH3 in the exhaust gas met the national emission limitation, while the deodorization of exhaust gas was required to remove odor smell.

Supplementary information

The online version contains supplementary material available at 10.1007/s13399-022-03722-4.

Evaluation of the effects of active fractions of chinese medicine formulas on IL-1β, IL-6, and TNF-α release from ANA-1 murine macrophages

ETHNOPHARMACOLOGICAL RELEVANCE

Yaotongning (YTN) is a traditional Chinese Medicine (TCM) that contains ten component medicinal materials (CMMs) and uses Chinese rice wine as a vehicle to enhance its efficacy. YTN has been used for rheumatoid arthritis (RA) treatment in China for decades and has been reported to have anti-inflammatory and analgesic effects, as well as to strengthen the immune system.

AIM OF THE STUDY

The present work quantitatively evaluated the in vitro effects of active fractions from the ten CMMs that make up YTN and eight additional herbs commonly used in TCM formulas for RA treatment, as well as different combinations of these active fractions, on cellular immune response; the findings were used to determine which active fractions are responsible for promoting an immune response, and to assess whether YTN is superior to other similar formulas and whether YTN can be improved by simplifying its formula from the point of its cellular immunomodulatory activity.

MATERIALS AND METHODS

Using the YTN formulation principles and some concepts in combinatorial chemistry, 27 TCM samples were designed by combining some or all of the active fractions of YTN and other eight herbs used for RA treatment. Release of interleukin-1β (IL-1β), interleukin-6 (IL-6), and tumor necrosis factor-alpha (TNF-α) from ANA-1 murine macrophages was measured using an enzyme-linked immunosorbent assay (ELISA). The immunoregulatory effects of the TCM samples were evaluated by comparing their half-effective concentrations (EC50) for stimulating the release of these cytokines.

RESULTS

Among the investigated active fractions, the flavonoids from Carthamus tinctorius (Fct), Davallia mariesii (Fdm), and Cinnamomum cassia Twig volatile oils (Vca) from the eight selected herbs effectively promoted IL-1β and IL-6 release from ANA-1 cells. Saponins from the YTN CMM Glycyrrhiza uralensis (Sgu) were the most potent promoters of IL-1β and TNF-α release. The aqueous extract of YTN CMM Eupolyphaga sinensis (Ves) strongly enhanced the release of IL-1β, IL-6, and TNF-α from ANA-1 cells. The EC50 values for stimulating the secretion of IL-1β, IL-6, and TNF-α could be determined for only six samples. The full YTN formula and the sample containing 50% Glycyrrhiza uralensis saponins, 25% of the mixture of alkaloids, and 25% of the mixture of all flavonoids exhibited good comprehensive cellular immunomodulatory activity. The immunomodulatory activity of the complete YTN formula was better than that of the sample containing all active fractions of YTN without Chinese rice wine (the YTN vehicle).

CONCLUSIONS

Sgu and Ves are the primary active fractions of YTN involved in stimulating immune responses. The YTN prescription was reasonably effective at promoting cellular immune responses. Chinese rice wine, the YTN vehicle, strengthened the immunoregulatory activity of YTN. The results of this study demonstrate that the YTN recipe could be improved by reducing the number of CMMs and altering some active fractions without reducing its activity to promote cellular immune responses.

Determination of aroma components in Chinese southwest tobacco by directly suspended droplet microextraction combined with GC-MS

In this paper, a simple and efficient approach, directly suspended droplet microextraction (DSDME), has been applied to extract aroma components in Chinese southwest tobacco prior to analysis by gas chromatography-mass spectrometry (GC-MS). The extraction parameters such as organic solvent type, extraction time, temperature, stirring speed and volume were systemically optimized. A single drop of cyclohexane was placed on the top of the aqueous sample which was used as solvent. Under the optimal conditions of DSDME, 62 aroma components of tobacco were analyzed and identified by GC-MS. The approach was used to determine some important aromas in tobacco with the relative recoveries ranged from 75.92 to 102.88%, relative standard deviations in the range of 3.40-7.14% (n = 5) and the limits of detection of 0.0002-0.002 μg/mL. Moreover, the DSDME was applied to identify the aromatic components in Chinese southwest tobacco in this research for the first time and the results suggested that the method can be used as rapid determination of the tobacco. This method can enhance the extracting rate of tobacco aromatic components and meet the need of qualitative analysis of large amount samples.

Quantitative evaluation of in vitro effects and interactions of active fractions in a Chinese medicinal formula (Yaotongning Capsule) on rat chondrocytes

ETHNOPHARMACOLOGICAL RELEVANCE

Yaotongning Capsule (YTNC) is a Traditional Chinese Medicinal (TCM) formula that has been demonstrated to be effective for osteoarthritis (OA) treatment in clinical use. Many compounds and 10 component medicinal materials (CMMs for short, i.e., the fundamental elements used in TCM formulas) in YTNC are challenging to study the pharmacological effects and interactions of the CMMs. Besides, it is difficult to know whether the YTNC formula is reasonable, and if YTNC formula could be improved without comparing YTNC with other TCM formulas of treating OA. Based on different combinations of the active fractions from the 10 CMMs of YTNC and eight additional herbs frequently used in the TCM formulas of treating OA, the present study evaluated systematically the in vitro effects of these active fractions and the interactions among the active fractions from YTNC on rat chondrocytes to find possible solutions of the above questions.

MATERIALS AND METHODS

Based on the formulation of YTNC and the concept of combinatorial chemistry, the active fractions were applied to form the whole YTNC prescription (i.e., the combination of all YTNC active fractions and the extract of YTNC׳s vehicle), five disassembled formulas of YTNC (i.e., the combinations of some active fractions in YTNC) and 21 TCM samples consisted of different kinds of active fractions. The degenerated chondrocytes were induced with interleukin-1β (IL-1β), and then the half-effective concentration (EC50) value of the proliferation activity was analyzed to evaluate the 27 TCM samples. Nine samples were screened for the following evaluation on glycosaminoglycan (GAG) synthesis. Rat articular cartilage was obtained from six Sprague-Dawley rats (seven days of age), and then chondrocytes were isolated through enzymatic digestion with 0.2% Collagenase II. Proliferations of chondrocytes were examined through Cell Counting Kit-8 assay, when the intracellular levels of GAG were detected by 1,9-Dimethylmethylene blue staining. The interactions between the active fractions in YTNC were evaluated by comparing experimental EC50 values of the YTNC formulas with their additive EC50 values. The effects of every active fraction were estimated by comparing the EC50 values of the TCM sample containing the active fraction with that of the initial sample without the active fraction.

RESULTS

The whole formula of YTNC was very good at promoting the proliferation and GAG synthesis among all the 27 TCM samples. The vehicle of YTNC (Chinese rice wine) strengthened the two activities of YTNC. Refer to promoting the proliferation in chondrocytes, Davallia mariesii flavonoids (not belong to YTNC) were more potent than Glycyrrhiza uralensis flavonoids in YTNC, while the saponins, volatile oils and polysaccharides of YTNC were more potent than those from the eight additional herbs. Some samples including fewer active fractions were as good as YTNC. The YTNC formula and its disassembled formulas exhibited good activities both in promoting the proliferation and GAG synthesis, and the whole formula was most potent among the six YTNC formulas.

CONCLUSIONS

The YTNC formula is reasonable and has advantage in promoting the proliferation and GAG synthesis in IL-1β induced chondrocytes. YTNC׳s vehicle Chinese rice wine plays an important role in strengthening the activity of YTNC. YTNC may have the potential activity on treating chondrocytes degeneration caused by OA. However, the formula still can be simplified based on the combination of alkaloids, flavonoids and 50% of saponins from Glycyrrhiza uralensis to improve its quality controllability and safety. The present study can be a quite purposeful work for developing new YTNC-based formulas with maximal therapeutic efficacy and minimal adverse effects.

Quantitative evaluation of the in vitro effect and interactions of active fractions in Yaotongning-based formulae on prostaglandin E₂ production

ETHNOPHARMACOLOGICAL RELEVANCE

Traditional Chinese medicine (TCM) formula of Yaotongning Capsules (YTNC) is a common remedy to treat rheumatism (RA) in China and possesses diverse biological activities including anti-inflammation. However the effects of component material medicines (CMMs) in YTNC and different combinations of the CMMs on the efficacy of YTNC and the interactions of these CMMs have been being unclear due to ten CMMs and too many compounds involved in YTNC. Moreover, many TCM formulae are available for treating RA according to TCM theory. It is unknown if the YTNC prescription is better than other TCM formulae for treating RA or better efficacy could be obtained when some CMMs in YTNC are replaced by other herbs. Quantitatively investigate the in vitro effect of active fractions from the CMMs of YTNC and other eight herbs commonly used in the TCM formulae for RA treatment on anti-inflammatory activity of different combinations of the active fractions, the interactions of the active fractions to evaluate the reasonability, advantage (or disadvantage) of the YTNC prescription and to see if the prescription could be improved from the point of anti-inflammation.

MATERIALS AND METHODS

Twenty-six active fractions, which were categorized as alkaloids, flavonoids, saponins, volatile oils/aqueous extracts and polysaccharides were prepared to design TCM samples by combining some of the active fractions, based on the YTNC formulating principle, combination chemistry concept and the importance of the active fractions in YTNC. The anti-inflammatory activities of the samples were evaluated by their half-maximal inhibitory concentration (IC50) values that inhibiting the production of prostaglandin E2 (PGE2) in ANA-1 murine macrophages (ANA-1 cells). The cells plated in 96-well plates were classified into blank group and test sample group. Each group was stimulated with lipopolysaccharides (LPS, 1 mg/mL) for 2h. ANA-1 cells were pretreated with different concentrations of test samples prior to the addition of arachidonic acid (10 μmol/L). The supernatants were collected and measured using PGE2 ELISA Kit, and the cytotoxicity was assayed by cell counting Kit-8 (CCK8)-based test. The interactions of the active fractions in YTNC were evaluated by comparing the experimental IC50 values of the samples derived from YTNC to their corresponding additive IC50 values. The effect of each active fraction on cellular anti-inflammation-PGE2 secretion inhibition activity, and the reasonability, advantages (or disadvantages) of YTNC were evaluated based on the comparison of IC50 values of the samples.

RESULTS

The disassembled formulae consisted of some active fractions of YTNC and the whole prescription of YTNC consisted of the all active fractions from YTNC all demonstrate cellular anti-inflammatory activity, and there were no significant differences between these formulae. The vehicle of YTNC Chinese rice wine exhibits the ability to enhance the cellular anti-inflammation of YTNC. Synergistic effect exerts in the combination of alkaloids, flavonoids and saponins of YTNC, antagonistic or additive effects occur in the other combinations of active fractions from YTNC. The anti-inflammatory activities of some TCM samples which include some active fractions from the eight selected herbs are significantly higher than the samples derived from YTNC. The flavonoids of Carthamus tinctorius, the volatile oils of Cinnamomum cassia and Angelica pubescens perform better in cellular anti-inflammation than the flavonoids and volatile oils in YTNC.

CONCLUSIONS

The prescription of YTNC is reasonable in the view of anti-inflammation. The saponins and polysaccharides from the CMMs of YTNC have better anti-inflammatory activities than the saponins and polysaccharides from the other eight herbs. Reducing the varieties of YTNC CMMs and replacing the flavonoids and volatile oils of YTNC with the flavonoids of Carthamus tinctorius and the volatile oils of Cinnamomum cassia (or Angelica pubescens) would improve the safety and anti-inflammatory activity of YTNC. Synthetically evaluating various pharmacological activities of TCM formulae designed in the present work may lead to develop more effective and safer TCM using YTNC as prototypes.