Biochar derived from alkali-treated sludge residue regulates anaerobic digestion: Enhancement performance and potential mechanisms.

Biochar produced from bio-wastes has been widely used to promote the performance of anaerobic digestion. Waste activated sludge (WAS) is considered as a kind of popular precursor for biochar preparation, but the abundant resources in WAS were neglected previously. In this study, the roles of biochar prepared from raw, pretreated, and fermented sludge on anaerobic digestion were investigated. That is, parts of carbon sources and nutrients like polysaccharides, proteins, and phosphorus were firstly recovered after sludge pretreatment or fermentation, and then the sludge residuals were used as raw material to prepare biochar. The methane yield improved by 22.1% with adding the biochar (AK-BC) prepared by sludge residual obtained from alkaline pretreatment. Mechanism study suggested that the characteristics of AK-BC like specific surface area and defect levels were updated. Then, the conversion performance of intermediate metabolites and electro-activities of extracellular polymeric substances were up-regulated. As a result, the activity of electron transfer was increased with the presence of AK-BC, with increase ratio of 21.4%. In addition, the electroactive microorganisms like Anaerolineaceae and Methanosaeta were enriched with the presence of AK-BC, and the potential direct interspecies electron transfer was possibly established. Moreover, both aceticlastic and CO2-reducing methanogenesis pathways were improved by up-regulating related enzymes. Therefore, the proposed strategy can not only obtain preferred biochar but also recover abundant resources like carbon source, nutrients, and bioenergy.

Growth, mortality, and resource utilization of Gymnocypris chui in Langcuo Lake of Tibetan Plateau, China.

To investigate the growth, mortality, and resource utilization of Gymnocypris chui in Langcuo Lake of Tibetan Plateau, we measured body length and body weight of 389 fish based on four sampling surveys from October 2018 to November 2019. We identified the ages through lapillus. Based on frequency distribution of body length, we estimated the growth and mortality coefficients of G. chui in Langcuo Lake and the utilization status of existing population resources according to the Beverton-Holt dynamic comprehensive model. The results showed that G. chui were mainly composed of individuals aged 2 to 19 years in Langcuo Lake, with a length-body weight relationship equation of W=0.0105L3.042. The von Bertalanffy growth equation revealed that the fish had an asymptotic body length of L∞=37.28 cm, growth coefficient of k=0.160, and theoretical growth starting age of t0=-0.887 a. The total mortality coefficient Z was estimated as 0.48, based on the length-converted catch curve method. According to Pauly's empirical formula, the natural mortality coefficient M was 0.34, fishing mortality coefficient F was 0.14, and exploitation rate E was 0.29, indicating that G. chui resources in Langcuo Lake were not over-exploited. Considering the growth and mortality of G. chui in Langcuo Lake, fishing is appropriate, with a recommended fishing length of Lc=22.37 cm.

Technical guidelines for risk assessment of heavy metals in traditional Chinese medicines.

BACKGROUND: Heavy metals are considered a global concern because they can deteriorate human health. This guideline aims to scientifically evaluate health risk of heavy metals in TCM and to propose a reference for decision making in developing TCM-related health policies. METHODS: Using a multidisciplinary approach, a steering committee oversaw the development of the guideline. To obtain a reasonable and accurate risk assessment, key exposure assessment parameters for TCM, e.g., exposure frequency (EF), exposure duration (ED), and daily ingestion rate (IR) were obtained from surveys. In addition, transfer rates for heavy metals from Chinese medicinal materials (CMM) to decoctions or preparations were examined. RESULTS: Based on the scientific theory of risk control, the guideline was designed systematically, and principles and procedures for the risk assessment of heavy metals in TCM were identified. The guideline can be utilized to assess the risk of heavy metals in CMM and Chinese patent medicines (CPM). CONCLUSION: This guideline may help standardize the risk assessment of heavy metals in TCM, advance regulatory standards for heavy metals in TCM, and ultimately improve human health through scientific TCM usage in clinic.

Progress in quality control, detection techniques, speciation and risk assessment of heavy metals in marine traditional Chinese medicine.

Marine traditional Chinese medicines (MTCMs) hold a significant place in the rich cultural heritage in China. It plays an irreplaceable role in addressing human diseases and serves as a crucial pillar for the development of China's marine economy. However, the rapid pace of industrialization has raised concerns about the safety of MTCM, particularly in relation to heavy metal pollution. Heavy metal pollution poses a significant threat to the development of MTCM and human health, necessitating the need for detection analysis and risk assessment of heavy metals in MTCM. In this paper, the current research status, pollution situation, detection and analysis technology, removal technology and risk assessment of heavy metals in MTCM are discussed, and the establishment of a pollution detection database and a comprehensive quality and safety supervision system for MTCM is proposed. These measures aim to enhance understanding of heavy metals and harmful elements in MTCM. It is expected to provide a valuable reference for the control of heavy metals and harmful elements in MTCM, as well as the sustainable development and application of MTCM.

Insights into the roles and mechanisms of a green-prepared magnetic biochar in anaerobic digestion of waste activated sludge.

Methane is one of the most promising renewable energies to alleviate energy crisis or replace fossil fuels, which can be recovered from anaerobic digestion of bio-wastes. However, the engineering application of anaerobic digestion is always hindered by low methane yield and production rate. This study revealed the roles and mechanisms of a green-prepared magnetic biochar (MBC) in promoting methane production performance from waste activated sludge. Results showed that the methane yield reached 208.7 mL/g volatile suspended solids with MBC additive dosage of 1 g/L, increasing by 22.1 % compared to that in control. Mechanism analysis demonstrated that MBC could promote hydrolysis, acidification, and methanogenesis stages. This was because the properties of biochar were upgraded by loading nano-magnetite, such as specific surface area, surface active sites, and surface functional groups, which made MBC have greater potential to mediate electron transfer. Correspondingly, the activity of α-glucosidase and protease respectively increased by 41.7 % and 50.0 %, and then the hydrolysis performances of polysaccharides and proteins were improved. Also, MBC improved the secretion of electroactive substances like humic substances and cytochrome C, which could promote extracellular electron transfer. Furthermore, Clostridium and Methanosarcina, as well-known electroactive microbes, were selectively enriched. The direct interspecies electron transfer between them was established via MBC. This study provided some scientific evidences to comprehensively understand the roles of MBC in anaerobic digestion, with important implications for achieving resource recovery and sludge stabilization.

Pyrrolizidine alkaloids and health risk of three Boraginaceae used in TCM.

Objective: The aim of this study was to systematically explore the pyrrolizidine alkaloids (PAs) type, content and risk assessment in the three Boraginaceae used in TCM, involving Arnebia euchroma (AE), A. guttata (AG), and Lithospermum erythrorhizon (LE). Method: A UHPLC-MS/MS method was established to simultaneously determine eight pyrrolizidine alkaloids (PAs), namely intermedine, lycopsamine, intermedine N-oxide, lycopsamine N-oxide, 7-acetyllycopsamine, 7-acetyllycopsamine N-oxide, echimidine N-oxide, and echimidine in the three herbs. Based on these results, the risk assessment was explored using the routine margin of exposure (MOE) combined with relative potency (REP) for oral and external usage, respectively. Results and Conclusion: Imermedine and imermedine N-oxide were common components in the eight tested PAs. 7-acetyllycopsamine and its N-oxide were not detected in AE; echimidine and its N-oxide were not detected in AG; lycopsamine and its N-oxide, 7-acetyllycopsamine and its N-oxide were not detected in LE. The total contents of 8 PAs in 11 batches of AG was341.56-519.51 µg/g; the content in 15 batches of LE was 71.16-515.73 µg/g, and the content in 11 batches of AE was 23.35-207.13 µg/g. Based on these results, the risk assessment was explored using MOE combined with REP for oral and external usage, respectively. The findings of the risk assessment method of PAs based on MOE combined with the REP factor were consistent with the clinical toxicity results. As an oral herb, AE had low risk or no risk due to its low PA contents, and individual batches of LE were medium risk, while attention should be paid to their clinical use.AG was also low risk. The external use of the three Boraginaceae used in TCM was not associated with any risk. This study systematically explored the PA type and content of the three Boraginaceae used in TCM. Additionally, the refined risk assessment of PAs based on REP provided a more scientific basis for quality evaluation and rational use of the medicinal Boraginaceae used in TCM to improve public health.

Innovative accumulative risk assessment strategy of co-exposure of As and Pb in medical earthworms based on in vivo-in vitro correlation.

Recent studies on risks assessment of heavy metal(loid) are usually based on their total concentrations. Nevertheless, such an analysis does not assess their real amounts absorbed by human body. To scientifically assess the health risks, in this study medical earthworms were analyzed for relative bioavailability (RBA) of arsenic (As) and lead (Pb) using a multiple gavage mouse model with liver, kidneys, brain, and leg bones as biomarkers for the first time. Metal(loid) bioaccessibility was determined using in vitro physiologically based extraction (PBET) assay. We are the first to develop a novel accumulative health risk assessment strategy by combinational analyzing bioavailability of heavy metal(loid) levels to calculate target organ toxicity dose (TTD) modification of the HI and total cancer risk (TCR), which has capacity to evaluate the health risks of co-exposure of Pb and As in medical earthworms. As a result, As-RBA ranged from 7.2% to 45.1%, and Pb-RBA ranged from 16.1% to 49.8%. Additionally, As and Pb bioaccessibility varied from 6.7% to 48.3% and 7.8% to 52.5%, respectively. Moreover, strong in vivo-in vitro correlations (IVIVCs) were observed between metal-RBA and bioaccessibility, indicating the robustness of the in vitro PBET assay to predict metal-RBA in medical earthworms. The refined accumulative assessment strategy revealed that when adjusted by heavy metal(loid) bioavailability, the TTD modification of HI method typically exhibited an acceptable health risk caused by the co-exposure of Pb and As for cardiovascular, hematological, neurological, and renal system. The TCR levels associated with exposure to Pb and As due to the ingestion of medical earthworms were also acceptable after adjustment by bioavailability. Collectively, our innovation on accumulative risk assessment based on in vivo-in vitro correlation provides a novel approach engaging in assessing the risks due to co-exposure of As and Pb in medical earthworms.

Comparative analyses of complete chloroplast genomes reveal interspecific difference and intraspecific variation of Tripterygium genus.

The genus Tripterygium was of great medicinal value and attracted much attention on the taxonomic study using morphological and molecular methods. In this study, we assembled 12 chloroplast genomes of Tripterygium to reveal interspecific difference and intraspecific variation. The sequence length (156,692-157,061 bp) and structure of Tripterygium were conserved. Comparative analyses presented abundant variable regions for further study. Meanwhile, we determined the ndhB gene under positive selection through adaptive evolution analysis. And the phylogenetic analyses based on 15 chloroplast genomes supported the monophyly of Tripterygium hypoglaucum and the potential sister relationship between Tripterygium wilfordii and Tripterygium regelii. Molecular dating analysis indicated that the divergence time within Tripterygium was approximately 5.99 Ma (95% HPD = 3.11-8.68 Ma). The results in our study provided new insights into the taxonomy, evolution process, and phylogenetic construction of Tripterygium using complete plastid genomes.

[Determination of content of nine components in Xinnaojian preparations from different manufacturers by QAMS].

This study established the ultra-performance liquid chromatography(UPLC) fingerprint of Xinnaojian preparations. With epicatechin gallate as the internal reference substance, a quantitative analysis of multi-components by single marker(QAMS) method for determining the content of nine components(gallic acid, epigallocatechin, catechin, caffeine, epicatechin, epigallocatechin gallate, gallocatechin gallate, epicatechin gallate, and catechin gallate) in Xinnaojian preparations was established. The content determined by the external standard method(ESM) and QAMS method was compared to evaluate the feasibility and accuracy of QAMS method. The results showed that the standard curves of nine components had good linear relationship within the test concentration ranges. The average recoveries were 87.57%-107.4%, and the RSD was 1.5%-2.9%. Except epigallocatechin, the other components showed good repeatability under different experimental conditions. Epigallocatechin could meet the requirements in the same instrument and at the same wavelength. The results generally showed no significant difference between QAMS and ESM. The content of 9 components varied between the samples from different manufacturers, while it showed no significant difference between the samples from the same manufacturer. In summary, the UPLC fingerprint combined with QAMS method is feasible and accurate for determining the content of the nine components, which can be used for rapid quality evaluation of Xinnaojian preparations.

Role of extracellular polymeric substances in methane production from waste activated sludge induced by conductive materials.

Conductive materials have been widely used to establish direct interspecies electron transfer (DIET) for enhancing methane production potential from anaerobic digestion of waste activated sludge (WAS). However, the roles of extracellular polymeric substances (EPSs) affected by conductive materials on anaerobic digestion have been rarely reported. This study selected four widely used conductive materials, i.e., granular active carbon (GAC), biochar (BC), zero-valent iron (ZVI), and magnetite (Mag), to reveal the roles of EPSs. Results showed that methane production potentials were increased by BC, ZVI and Mag compared to that of control, with increase ratios of 13.4 %, 22.2 %, and 12.2 %, while a decrease was observed by GAC. The contents, components and characteristics of EPSs were all affected by conductive materials. The contents of EPSs were increased by ZVI and Mag, while they were decreased by BC and GAC. The ratios between proteins and polysaccharides (PN/PS) in loosely bound EPSs (LB-EPSs) were reduced in all groups, while they were similar in tightly bound EPSs (TB-EPSs) of ZVI and Mag groups. In addition, the cytochrome C and redox properties were remarkably promoted in suspension rather than in LB- and TB-EPSs. It was found that the correlation relationships between the maximal methane production potential (Pmax) and PN/PS in EPSs were positive, as well as fluorescent substances, especially tyrosine-like and tryptophan-like substances, with R2 of 0.96 and 0.98. Furthermore, the correlation relationships also existed between EPSs and microbial communities. Clostridium and Methanobacterium, potential DIET partners, presented significant positive correlation relationships (P < 0.05) with Pmax, PN/PS and fluorescent substances in EPSs. The findings may provide some new insights for mechanism investigation of anaerobic digestion induced by conductive materials.

Novel Integrated Tiered Cumulative Risk Assessment of Heavy Metals in Food Homologous Traditional Chinese Medicine Based on a Real-Life-Exposure Scenario.

In order to serve population health better, the first integrated tiered decision tree for cumulative risk assessment of co-exposure of Pb-, Cd-, and As-associated health risks in food homologous traditional Chinese medicine (TCM) was designed, after measuring their concentrations by inductively coupled plasma-mass spectroscopy (ICP-MS). Basically, our three-step decision tree involving hazard quotient (HQ), hazard index (HI), and target-organ toxicity dose (TTD) modification of the HI method was developed to evaluate the potential risks of 949 batches of 15 types of food homologous TCM. To acquire a real-life exposure scenario, the cumulative risk assessment model was established by optimizing key parameters, such as ingestion rates, frequency, and duration of exposure to food homologous TCM based on questionnaire data. As a result, the mean concentrations of Pb, Cd, and As in 949 batches of food homologous TCM were 0.896, 0.133, and 0.192 mg/kg, respectively. The HQ values of As for Angelica sinensis (Oliv.) Diels and Houttuynia cordata Thunb. were 1.04 and 1.01, respectively, for females. Other HQs of Pb, Cd, or As in food homologous TCM were lower than 1 for both males and females. However, after rapid screening of the co-exposure health risks of heavy metals by the HI method, cumulative risk assessment results acquired by TTD modification of the HI method implied that the potential health risks associated with the co-exposure of Pb, Cd, and As in Lonicera japonica Thunb. and Houttuynia cordata Thunb. ingested as both TCM and food were of concern in the clinic. Additionally, the cumulative risks of Pb, Cd, and As in Mentha canadensis L., Chrysanthemum indicum L., and Zaocys dhumnades (Cantor) only used as food exceeded the human tolerance dose. Collectively, our innovation on the tiered strategy of decision tree based on a real-life exposure scenario provides a novel approach engaging in the cumulative risk assessment of heavy metals in food homologous TCM. All in all, such effort attempts to scientifically guide the rational use of TCM in the treatment of the complex diseases and the improvement of population health.

[Form and valence of arsenic in dry and fresh Cordyceps breeding products based on HPLC-ICP-MS and its risk assessment].

A comparative study was conducted for the first time on the form and valence of arsenic in the dry and fresh Cordyceps breeding products to clarify the specific morphology and valence of arsenic in Cordyceps breeding products and its safety. Arsenic betai-ne(AsB), arsenite(AsⅢ), dimethyl arsenic(DMA), arsenocholine(AsC), monomethyl arsenic(MMA), and arsenate(AsⅤ) in the dry and fresh samples were investigated using a bionic extraction method combined with HPLC-ICP-MS. The HPLC separation was performed on a DioncxIonPac~(TM) AS7 anion exchange column with a mobile phase of 100 mmol·L~(-1) ammonium carbonate-water for gradient elution at room temperature and the flow rate of 0.8 mL·min~(-1). HPLC was coupled with ICP-MS for the determination. The arsenic content was characterized in combination with chemometrics. The health safety risk of inorganic arsenic in the samples was assessed using the margin of exposure(MOE). The results of methodological validation showed that the six arsenic compounds showed good linearity(R~2>0.999) from 10 to 500 ng·mL~(-1), with precision RSDs of 1.8%-3.0%, recoveries(n=6) of 84.15%-98.28%, reproducibility RSDs of 6.4%-7.7%, and sample stability RSDs of 8.3%-14% within 10 h. Trace AsⅢ and AsⅤ were detected in 30 batches of dry and fresh Cordyceps breeding products, while arsenic compounds in other forms and valence were not detected. In the dry products, AsⅢ was 0.019-0.040 mg·kg~(-1) and AsV was 0.024-0.061 mg·kg~(-1), while in the fresh products, AsⅢ was 0.002 3-0.006 1 mg·kg~(-1) and AsⅤ was 0.008-0.016 mg·kg~(-1). The risk assessment results showed that the MOE of inorganic arsenic was much higher than 1 in both dry and fresh products, and the potential health safety risk of inorganic arsenic was low. The HPLC-ICP-MS method established in this study was efficient, rapid, accurate, and stable for the determination of six arsenic compounds in Cordyceps breeding products. The results of this study provide a basis for the safety and quality control of Cordyceps breeding products.

Potassium ferrate followed by alkali-stripping treatment to achieve short-chain fatty acids and nitrogen recovery from waste activated sludge.

Waste activated sludge (WAS) is a potential resource to achieve carbon-neutral goal of wastewater treatment plant. However, the solubilization is always the rate-limiting step for resource recovery from anaerobic digestion of WAS. This study reported a novel strategy, i.e., potassium ferrate (PF) followed by alkali-stripping treatment, to achieve short-chain fatty acids (SCFAs) and nitrogen recovery from WAS. Results showed that whether the stripping process was conducted under alkaline condition or not, the SCFAs production potential was increased rather than reduced. The promoted SCFAs production was due to the accelerated solubilization and hydrolysis stages but the inhibited methanogenesis stage. The SCFAs yield reached 258 mg chemical oxygen demand (COD)/g volatile suspended solids (VSS), and the carbon source, including SCFAs, soluble polysaccharides and proteins, reached 384 mg COD/g VSS. The potentially recovered nitrogen was about 8.71 mg NH4+-N/g VSS. This work may provide some new solutions for enhancing resource recovery from WAS.

A strategy for quality control of ginkgo biloba preparations based on UPLC fingerprint analysis and multi-component separation combined with quantitative analysis.

BACKGROUND: Many studies have assessed the fingerprint and quantitative analysis of Ginkgo biloba preparations, but the fingerprint mainly focuses on flavonoid glycosides. However, according to our previous study, the differences among diverse manufacturers mainly involve organic acids. METHODS: A novel reverse-phase liquid chromatography assay using diode array detection was developed for evaluating Ginkgo biloba preparations for quality based on a chromatographic fingerprint allowing the simultaneous assessment of eleven compounds, including four organic acids, six flavonol glycosides and one flavonoid aglycone. And the method was applied to 51 batches of Ginkgo biloba preparations from manufacturers in China. Chemometric approaches were performed for evaluating 51 batches of Ginkgo biloba preparations from various manufacturers. RESULTS: The similarity values among the chromatograms of 51 samples ranged from 0.45 to 1.00, showing that the quality of Ginkgo biloba preparations produced by different manufacturers varied greatly. Data analysis of the 51 batches of GBP samples suggested significant variations of the total contents of all 11 targets, also demonstrating the quality difference of GBP samples. There were significant differences in organic acids in particular. CONCLUSION: Combining the chemical fingerprint and quantitative assessment revealed significant variations in the examined commercial products with regard to organic acids. Thus, this study provided a more comprehensive tool for monitoring the quality consistency of Ginkgo biloba preparations.

Role and significance of water and acid washing on biochar for regulating methane production from waste activated sludge.

Methane recovered from anaerobic digestion of waste activated sludge (WAS) can be used as the energy supplement of the wastewater treatment plant, benefiting to its carbon-neutral operation. In order to enhance methane production, biochar (BC) has been widely selected as conductive material to build direct interspecies electron transfer (DIET) in anaerobic digestion of WAS. However, the role and significance of washing strategies, including water and acid washing, on BCs for regulating methane production have not been reported. This study selected the frequently used woody- (W) and straw (S)-BCs as mode. Compared to raw W-BC, water and acid washing W-BC increased the methane yields by 19.1% and 15.7%, respectively. Differently, the methane yields among raw, water and acid washing S-BCs were similar. Mechanism study showed that both the two washing strategies optimized the properties of raw W-BC for promoting methane production. Water and acid washing W-BCs increased the electron transfer functional groups, such as ketones and quinones, which were not observed in S-BCs. Moreover, the electron-active microorganisms were enriched with the presence of water and acid washing W-BCs, and the predominant pathway for methane production shifted from hydrogentrophic to acetotrophic and DIET methanogenesis, while the microbial communities, including bacteria and archaea, were similar with the presence of raw, water and acid washing S-BCs. These findings of this work provide some new insights for production improvement regulation of methane from anaerobic digestion of wastes induced by BCs.

Freezing-low temperature treatment facilitates short-chain fatty acids production from waste activated sludge with short-term fermentation.

This study proposed a novel and high-efficiency strategy, i.e., freezing followed by low-temperature thermal treatment, to significantly promote short-chain fatty acids (SCFAs) production from waste activated sludge compared to traditional freezing/thawing treatment. The maximal production of SCFAs was 212 mg COD/g VSS with a shortened retention time of five days, and the potentially recovered carbon source, including SCFAs, soluble polysaccharides and proteins, reached 321 mg COD/g VSS, increased by 92.1 and 28.3% compared to sole freezing and thermal treatment. Both the solubilization and hydrolysis steps of WAS were accelerated, and the acid-producing microorganisms, such as Macellibacteroides, Romboutsia and Paraclostridium, were greatly enriched, with a total abundance of 13.9%, which was only 0.54% in control. Interestingly, the methane production was inhibited at a shortened retention time, resulting in SCFAs accumulation, whereas it was increased by 32.0% at a longer sludge retention time, providing a potential solution for energy recovery from WAS.

Novel bioavailability-based risk assessment of Cd in earthworms and leeches utilizing in vitro digestion/Caco-2 and MDCK cells.

In the present study, the oral bioavailability of cadmium (Cd) in earthworms and leeches was investigated through in vitro physiologically based extraction test (PBET) digestion/Caco2 and MDKC cell models. We are the first to create an innovative assessment strategy which has capacity to offer a more precise evaluation of Cd-associated health risks in traditional animal medicines (TAMs), by combinational usage of bioavailable Cd levels, the duration and frequency of the exposure to TAMs obtained by questionnaire data, as well as safety factor of TAMs. Our data showed that the percentage of bioavailability for Caco-2 cells in earthworms and leeches ranged from 3.29 to 14.17% and 4.32 to 12.61%, respectively. The percentage of bioavailability of MDCK cells in earthworms and leeches ranged from 4.83 to 15.74% and 6.53 to 15.04%, respectively. After adjusting by the bioavailability of Cd to target hazard quotient (THQ), excitingly, our findings manifested that the health risks induced by the ingestion of earthworms and leeches were acceptable in the clinic. Our key findings suggest that bioavailability characterization cannot be ruled out and health risks should be assessed on the basis of the bioavailable Cd levels rather than total levels. Our novel strategy provides insight into the bio-accumulation of Cd in organisms as well as a more realistic and accurate assessment of Cd-associated health risks in TAMs, with the main purpose of improving public health by scientifically using TAMs.

Stepwise freezing-thawing treatment promotes short-chain fatty acids production from waste activated sludge.

Waste activated sludge (WAS), as the byproducts of wastewater treatment plants, has been greatly produced. With high cost and environmental risk of WAS disposal, to explore a low-cost and environment-friendly technology has been a great challenge. Considering that WAS is a collection of organic matters, anaerobic fermentation has been selected as a sustainable way to simultaneously recover resources and reduce environmental pollution. To recover short-chain fatty acids (SCFAs) has gained great concern because of the high value-added application and high-efficiency production process. Considering the temperature in some areas of the world can reach to below 0 °C, this study proposed an efficient strategy, i.e., stepwise freezing and thawing treatment, to promote SCFAs production. The maximal production of SCFAs, i.e., 246 mg COD/g volatile suspended solid, was obtained with the shortened retention time of five days. Mechanistic studies showed that the solubilization of both extracellular polymeric substances (EPSs) and microbial cells could be accelerated, with the EPSs removal of 58.3% for proteins and 59.0% for polysaccharides. Also, the hydrolysis process was promoted to provide more substrates for subsequent acidogenisis, and the functional microorganisms, such as Romboutsia, Paraclostridium, Macellibacteroides and Conexibacter, were greatly enriched, with a total abundance of 26.2%. Moreover, compared to control, methanogenesis was inhibited at a shortened sludge retention time (e.g., five days), which benefited to the accumulation of SCFAs, but the methane production was increased by 25.2% at a longer sludge retention time (e.g., ten days). Thus, these findings of this work may provide some new solutions for the enhanced resource recovery from WAS, and further for carbon-neutral operation of wastewater treatment plants.

[Current situation and problems of national standards for Chinese medicinal materials].

To learn the current situation and strengthen the management of national standards for Chinese medicinal materials, we sorted out the relevant national standards. According to incomplete statistics, there are 1 185 kinds of Chinese medicinal materials, including 1 024 kinds of plant medicines, 106 kinds of animal medicines, and 54 kinds of mineral medicines, in addition to ethnic medicinal materials with different functions. The relevant standards include 819 Pharmacopoeia standards, 342 standards issued by the Ministry of Health or National Medicinal Products Administration, 7 standards for new medicinal materials, and 17 standards for imported medicinal materials. In this paper, the sources of standards as well as the distribution of families and genera and the distribution of medicinal parts of medicinal materials are analyzed. The suggestions are as follows:(1)to improve the coordination among different national standards of Chinese medicinal materials;(2)to improve the standardization and controllability of relevant standards;(3)to revise the issued standards for Chinese medicinal materials(including Tibetan, Uygur, and Mongolian medicinal materials).

[Simultaneous determination of six pyrrolizidine alkaloids in different parts of Emilia sonchifolia by UPLC-MS/MS].

This study aims to develop a UPLC-MS/MS method for simultaneous determination of six pyrrolizidine alkaloids(PAs)--intermedine N-oxide(ImNO), lycopsamine N-oxide(LyNO), seneciphylline(Sp), seneciphylline N-oxide(SpNO), senecionine N-oxide(SnNO), and senkirkine(Sk) in different parts of Emilia sonchifolia. UPLC conditions are as follows: ACQUITY UPLC HSS T3 column(2.1 mm×100 mm, 1.8 µm), mobile phase consisting of 0.05% formic acid and 2.5 mmol·L~(-1) ammonium formate in water(A)-0.05% formic acid and 2.5 mmol·L~(-1) ammonium formate in acetonitrile(B) for gradient elution. MS conditions are as below: electrospray ionization(ESI) in the positive ion mode, multiple reaction monitoring(MRM), and the content of the six PAs was calculated with the external standard method. The results suggested the differences in the six PAs among different parts of E. sonchifolia. Sk was detected in all the four parts, with similar content. SnNO also existed in all the four parts, but the content in roots was significantly higher than that in other parts. Sp and SpNO were found in both roots and flowers, with the content higher in the former than in the later. ImNO and LyNO were only found in leaves, and the content was low. Among the six components detected, ImNO, LyNO, and SpNO were found and determined for the first time, which enriched the toxic components and laid a scientific basis for the quality and safety evaluation of E. sonchifolia.