Efficient identification of palatability-related genes using QTL mapping in rice breeding.

The gelatinization temperature of rice is an important factor in determining the eating and cooking quality, and it affects consumer preference. The alkali digestion value (ADV) is one of the main methods used to test the quality of rice and has a high correlation with the gelatinization temperature. For the development of high-quality rice, it is important to understand the genetic basis of palatability-related traits, and QTL analysis is a statistical method linking phenotypic data and genotype data and is an effective method to explain the genetic basis of variation in complex traits. QTL mapping related to the ADV of brown and milled rice was performed using the 120 Cheongcheong/Nagdong double haploid (CNDH) line. As a result, 12 QTLs related to ADV were detected, and 20 candidate genes were selected from the RM588-RM1163 region of chromosome 6 through screening by gene function analysis. The comparison of the relative expression level of candidate genes showed that OsSS1q6 is highly expressed in CNDH lines with high ADV in both brown rice and milled rice. In addition, OsSS1q6 has high homology with the starch synthase 1 protein and interacts with various starch biosynthesis-related proteins, such as GBSSII, SBE, and APL. Therefore, we suggest that OsSS1q6 identified through QTL mapping could be one of the various genes involved in the gelatinization temperature of rice by regulating starch biosynthesis. This study can be used as basic data for breeding high-quality rice and provides a new genetic resource that can increase the palatability of rice. Supplementary Information: The online version contains supplementary material available at 10.1007/s11032-023-01392-2.

Palladium oxidative addition complex-enabled synthesis of amino-substituted indolyl-4(3H)-quinazolinones and their antitumor activity evaluation.

The indolyl-4(3H)-quinazolinone core is an important structural motif in functional molecules. However, few methods exist for its direct modification, which limits its potential application. Reported herein is a palladium-mediated amination of halogen-containing indolyl-4(3H)-quinazolinones with a variety of primary and secondary amines via the corresponding palladium oxidative addition complexes. The protocol allows the facile synthesis of indolyl-4(3H)-quinazolinone derivatives with amino groups at all the positions of the benzene ring in moderate to good yields with mild reaction conditions and good functional group tolerance. Furthermore, the antitumor activity of these products was evaluated.

Establishment of an in vitro safety assessment model for lipid-lowering drugs using same-origin human pluripotent stem cell-derived cardiomyocytes and endothelial cells.

Cardiovascular safety assessment is vital for drug development, yet human cardiovascular cell models are lacking. In vitro mass-generated human pluripotent stem cell (hPSC)-derived cardiovascular cells are a suitable cell model for preclinical cardiovascular safety evaluations. In this study, we established a preclinical toxicology model using same-origin hPSC-differentiated cardiomyocytes (hPSC-CMs) and endothelial cells (hPSC-ECs). For validation of this cell model, alirocumab, a human antibody against proprotein convertase subtilisin kexin type 9 (PCSK9), was selected as an emerging safe lipid-lowering drug; atorvastatin, a common statin (the most effective type of lipid-lowering drug), was used as a drug with reported side effects at high concentrations, while doxorubicin was chosen as a positive cardiotoxic drug. The cytotoxicity of these drugs was assessed using CCK8, ATP, and lactate dehydrogenase release assays at 24, 48, and 72 h. The influences of these drugs on cardiomyocyte electrophysiology were detected using the patch-clamp technique, while their effects on endothelial function were determined by tube formation and Dil-acetylated low-density lipoprotein (Dil-Ac-LDL) uptake assays. We showed that alirocumab did not affect the cell viability or cardiomyocyte electrophysiology in agreement with the clinical results. Atorvastatin (5-50 µM) dose-dependently decreased cardiovascular cell viability over time, and at a high concentration (50 µM, ~100 times the normal peak serum concentration in clinic), it affected the action potentials of hPSC-CMs and damaged tube formation and Dil-Ac-LDL uptake of hPSC-ECs. The results demonstrate that the established same-origin hPSC-derived cardiovascular cell model can be used to evaluate lipid-lowering drug safety in cardiovascular cells and allow highly accurate preclinical assessment of potential drugs.

Identification of a Major QTL and Validation of Related Genes for Tiller Angle in Rice Based on QTL Analysis.

An ideal plant architecture is an important condition to achieve high crop yields. The tiller angle is an important and complex polygenic trait of rice (Oryza sativa L.) plant architecture. Therefore, the discovery and identification of tiller angle-related genes can aid in the improvement of crop architecture and yield. In the present study, 222 SSR markers were used to establish a high-density genetic map of rice doubled haploid population, and a total of 8 quantitative trait loci (QTLs) were detected based on the phenotypic data of the tiller angle and tiller crown width over 2 years. Among them, four QTLs (qTA9, qCW9, qTA9-1, and qCW9-1) were overlapped at marker interval RM6235-RM24288 on chromosome 9 with a large effect value regarded as a stable major QTL. The selected promising related genes were further identified by relative gene expression analysis, which gives us a basis for the future cloning of these genes. Finally, OsSAURq9, which belongs to the SMALL AUXIN UP RNA (SAUR), an auxin-responsive protein family, was selected as a target gene. Overall, this work will help broaden our knowledge of the genetic control of tiller angle and tiller crown width, and this study provides both a good theoretical basis and a new genetic resource for the breeding of ideal-type rice.

QTL Mapping and Candidate Gene Analysis for Seed Germination Response to Low Temperature in Rice.

Low temperature is a serious threat to the seed emergence of rice, which has become one of the main limiting factors affecting rice production in the world. It is of great significance to find the candidate genes controlling low-temperature tolerance during seed germination and study their functions for breeding new rice cultivars with immense low-temperature tolerance during seed germination. In the current experiment, 120 lines of the Cheongcheong Nagdong Double Haploid (CNDH) population were used for quantitative trait locus (QTL) analysis of low-temperature germinability. The results showed a significant difference in germination under low different temperature (LDT) (15 °C, 20 °C) conditions. In total, four QTLs were detected on chromosome 3, 6, and 8. A total of 41 genes were identified from all the four QTLs, among them, 25 genes were selected by gene function annotation and further screened through quantitative real-time polymerase chain reaction (qRT-PCR). Based on gene function annotation and level of expression under low-temperature, our study suggested the OsGPq3 gene as a candidate gene controlling viviparous germination, ABA and GA signaling under low-temperature. This study will provide a theoretical basis for marker-assisted breeding and lay the basis for further mining molecular mechanisms of low-temperature germination tolerance in rice.

[Neuroprotective effect of cinnamaldehyde in MPTP-induced mouse model of subacute Parkinson's disease].

This paper aims to explore the neuroprotective effect of cinnamaldehyde(CA) in mice with 1-methyl-4-phenyl-1,2,3,6-tetrahydropyridine(MPTP)-induced subacute Parkinson's disease(PD) and the mechanism. To be specific, male C57 BL/6 mice(n=72, SPF) were randomized into control group, model group, positive control(madopar 0.1 mg·g~(-1)) group, and low-dose, me-dium-dose, and high-dose CA groups(0.15, 0.30, 0.60 mg·g~(-1)). MPTP(intraperitoneal injection, 0.03 mg·g~(-1), once a day for 5 days) was used to induce subacute PD in mice except for the control group. The administration began from the day of modeling and lasted 19 days. On the 0 th, 12 th, and 19 th day, the open field test, pole test, and rotarod test were carried out. After the tests, the mice were killed and brains were separated. In addition, the organ index was measured. The number of cells in substantia nigra(SN) in the midbrain of MPTP-induced PD model mice was detected based on hematoxylin and eosin(HE) staining. The levels of tyrosine hydroxylase(TH)-and α-synuclein(α-Syn)-positive cells in SN were determined by immunohistochemical staining, and the protein levels of TH and α-Syn in SN by Western blot. The results showed that the MPTP-stimulated mice had abnormal behaviors such as erect hair, arched back, rigidity of the tail, slow movement, and tremor, decreased number of crossings and rearing, increased frequency of urination and defecation, longer time of pole climbing, and shorter time of staying on the rotating rod. In addition, the mice showed obvious damage of neurons in the SN and reduced neuron cells in irregular arrangement with some shrinking. In addition, the average optical density of TH in SN decreased and that of α-Syn increased. All these suggested the successful modeling. CA displayed obvious therapeutic effect on the PD mice, as manifested by the increased number of crossings and rearing, decreased frequency of urination and defecation, shorter time of climbing pole, longer time of staying on the rotating rod, and more neuron cells in the SN with a few pykno-tic cells. Moreover, CA significantly alleviated the decrease of TH and the overexpression of α-Syn in SN. As a result, the MPTP-induced injury of dopaminergic neurons was alleviated. The performance of 0.3 mg·g~(-1) CA was the best. This study is expected to lay a scientific basis for the development of CA products.

Bacillus subtilis BSH has a protective effect on Salmonella infection by regulating the intestinal flora structure in chickens.

Salmonellosis is a worldwide zoonotic disease that poses a serious threat to the reproduction of livestock and poultry and the health of young animals. Probiotics including Bacillus species, have received increasing attention as a substitute for antibiotics. In this study, chicks infected with Salmonella were fed feed supplemented with the BSH to observe the pathological changes in the liver, detect the number of viable bacteria in the liver and spleen, and record the death of the chicks. The results showed that BSH could reduce the pathological changes in the liver and the invasion of Salmonella into the liver and spleen of chicks. In addition, the survival rate of chicks in the BSH experimental group was 60%, while that in the infected control group was 26%, indicating that BSH had a protective effect on chicks infected with Salmonella. Finally, the fecal microflora of 9-day-old chicks was analyzed by 16S rRNA high-throughput sequencing. The results showed that Salmonella infection could cause intestinal flora changes, while BSH could alleviate this change. In addition, BSH also promoted the proliferation of Lactobacillus salivarius in the cecum of chick. This study emphasized that BSH has anti- Salmonella infection effects in chickens and can be used as a candidate microecological preparation strain.

Combined analysis of whole-exon sequencing and lncRNA sequencing in type 2 diabetes mellitus patients with obesity.

This study sought to find more exon mutation sites and lncRNA candidates associated with type 2 diabetes mellitus (T2DM) patients with obesity (O-T2DM). We used O-T2DM patients and healthy individuals to detect mutations in their peripheral blood by whole-exon sequencing. And changes in lncRNA expression caused by mutation sites were studied at the RNA level. Then, we performed GO analysis and KEGG pathway analysis. We found a total of 277 377 mutation sites between O-T2DM and healthy individuals. Then, we performed a DNA-RNA joint analysis. Based on the screening of harmful sites, 30 mutant genes shared in O-T2DM patients were screened. At the RNA level, mutations of 106 differentially expressed genes were displayed. Finally, a consensus mutation site and differential expression consensus gene screening were performed. In the current study, the results revealed significant differences in exon sites in peripheral blood between O-T2DM and healthy individuals, which may play an important role in the pathogenesis of O-T2DM by affecting the expression of the corresponding lncRNA. This study provides clues to the molecular mechanisms of metabolic disorders in O-T2DM patients at the DNA and RNA levels, as well as biomarkers of the risk of these disorders.

Proteomics Analysis of Testis of Rats Fed a High-Fat Diet.

BACKGROUND/AIMS: The adverse effects of obesity on male fertility have been widely reported. In recent years, the relationship between the differential expression of proteins and long non-coding RNAs with male reproductive disease has been reported. However, the exact mechanism in underlying obesity-induced decreased male fertility remains unclear. METHODS: We used isobaric tags for relative and absolute quantification to identify differential protein expression patterns in the testis of rats fed a high-fat diet and normal diet. A microarray-based gene expression analysis protocol was used to compare the differences in long non-coding RNAs in high-fat diet-fed and normal diet-fed rats. Five obviously upregulated or downregulated proteins were examined using western blot to verify the accuracy of their expression. Then, we carried out functional enrichment analysis of the differentially expressed proteins using gene ontology and pathway analysis. Finally, the metabolic Gene Ontology terms and pathways involved in the differential metabolites were analyzed using the MetaboAnalyst 2.0 software to explore the co-expression relationship between long non-coding RNAs and proteins. RESULTS: We found 107 proteins and 263 long non-coding RNAs differentially expressed between rats fed a high-fat diet and normal diet. The Gene Ontology term enrichment analysis showed that the protein function most highly enriched was related to negative regulation of reproductive processes. We also found five Gene Ontology terms and two metabolic pathways upregulated or downregulated for both proteins and long non-coding RNAs. CONCLUSION: The study revealed different expression levels for both proteins and long non-coding RNAs and showed that the function and metabolic pathways of differently expressed proteins were related to reproductive processes. The Gene Ontology terms and metabolic pathways upregulated or downregulated in both proteins and long non-coding RNAs may provide new candidates to explore the mechanisms of obesity-induced male infertility for both protein and epigenetic pathways.

Molecular characterization and expression profiling of ryanodine receptor gene in the pink stem borer, Sesamia inferens (Walker).

The susceptibilities of three field populations of pink stem borer (PSB), Sesamia inferens (walker) to diamide insecticides, chlorantraniliprole and flubendiamide, were evaluated in this study. The results showed that these PSB field populations were still sensitive to the two diamide insecticides after many years of exposure. To further understand PSB and diamide insecticide, the full-length ryanodine receptor (RyR) cDNA (named as SiRyR), the molecular target of diamide insecticides was cloned from PSB and characterized. The SiRyR gene contains an open reading frame of 15,420 nucleotides, encoding 5140 amino acid residues, which shares 77% to 98% sequence identity with RyR homologous of other insects. All hallmarks of RyR proteins are conserved in the SiRyR protein, including the conserved C-terminal domain with the consensus calcium-biding EF-hands (calcium-binding motif), the six transmembrane domains, as well as mannosyltransferase, IP3R and RyR (pfam02815) (MIR) domains. Real-time qPCR analysis revealed that the highest mRNA expression levels of SiRyR were observed in pupa and adults, especially in males. SiRyR was expressed at the highest level in thorax, and the lowest level in wing. The full genetic characterization of SiRyR could provide useful information for future functional expression studies and for discovery of new insecticides with selective insecticidal activity.

Anticancer Phenolics from Dryopteris fragrans (L.) Schott.

Cancer is one of the most major diseases that threatens human health and life. The aim of this work was to obtain novel anticancer molecules from D. fragrans, a kind of medicinal plant. The structure of the new compound was identified using spectroscopic data (¹H-NMR, 13C-NMR and two dimensions NMR). Its anticancer properties were evaluated using the 3-(4,5-dimethyl-2-thiazolyl)-2,5-diphenyl-2-H-tetrazolium bromide (MTT) assay against four human cells including lung cancer cells (A549), breast cancer cells (MCF-7), gastric cancer cells (SGC7901) and noncancerous human umbilical vein endothelial cells (HUVEC). A new phenylpropanoid-(E)-caffeic acid-9-O-ß-d-xylpyranosyl-(1→2)-ß-d-glucopyranosyl ester (1), with seven known compounds (2-8)-was isolated. The IC50 value of compound 1 against MCF-7 cells was 2.65 ± 0.14 µM, and the IC50 values of compound 8 against three cancer cells were below 20 µM.

Characterization of Klebsiella sp. strain S1: a bacterial producer of secoisolariciresinol through biotransformation.

Secoisolariciresinol (SECO) is a lignan of potential therapeutic value for diseases such as cancer, but its use has been limited by the lack of ideal production methods, even though its precursors are abundant in plants, such as flaxseeds. Here, we report the characterization of a bacterial strain, S1, isolated from the human intestinal flora, which could produce secoisolariciresinol by biotransformation of precursors in defatted flaxseeds. This bacterium was a Gram-negative and facultatively anaerobic straight rod without capsules. Biochemical assays showed that it was negative for production of oxidase, lysine decarboxylase, ornithine decarboxylase, arginine dihydrolase, and ß-glucolase. The G + C content of genomic DNA was 57.37 mol%. Phylogenetic analysis by 16S rRNA and rpoB gene sequences demonstrated S1's close relatedness to Klebsiella. No homologues were found for wzb or wzc (capsular genes), which may explain why Klebsiella sp. strain S1 does not have the capsule and was isolated from a healthy human individual. Based on the percentages of homologous genes with identical nucleotide sequences between the bacteria in comparison, we found that clear-cut genetic boundaries had been formed between S1 and any other Klebsiella strains compared, dividing them into distinct phylogenetic lineages. This work demonstrates that the intestinal Klebsiella, well known as important opportunistic pathogens prevalent in potentially fatal nosocomial infections, may contain lineages that are particularly beneficial to the human health.

Involvement of aurantiactinomyxon in the life cycle of Thelohanellus testudineus (Cnidaria: Myxosporea) from allogynogenetic gibel carp Carassius auratus gibelio, with morphological, ultrastructural, and molecular analysis.

During the investigation of actinosporean fauna diversity from commercial fish ponds in Hubei Province, China, a novel aurantiactinomyxon type was found from Branchiura sowerbyi. Spore body of the aurantiactinomyxon was ellipsoidal in side view and triangular in apical view, 15.5 ± 0.5 (14.5-16.4) µm in diameter; three leaf-like caudal processes were approximately equal, measuring 13.2 ± 0.9 (11.5-16.2) µm long and 7.4 ± 0.4 (6.7-8.0) µm wide at the base; three polar capsules were located at the apex of spore body, globular in apical view, 2.2 ± 0.1 (2.0-2.3) µm in diameter, and pyriform in side view, 2.5 ± 0.2 (2.3-2.9) µm in length and 2.0 ± 0.2 (1.8-2.4) µm in width; a total of 32 germ cells were observed within the sporoplasm. Ultrastructural analysis showed that the development was asynchronous between pansporocysts but synchronous within a pansporocyst. The formation of sporoblast and the development of sporogonic stage were also described and discussed. The 18S ribosomal DNA sequences of the current aurantiactinomyxon type corresponded to that of a previously reported Thelohanellus testudineus, suggesting that the newly identified aurantiactinomyxon type is the actinosporean stage in the life cycle of T. testudineus.

A New Human Cancer Cell Proliferation Inhibition Sesquiterpene, Dryofraterpene A, from Medicinal Plant Dryopteris fragrans (L.) Schott.

The global burden of cancer continues to increase largely with the aging and growth of the world population. The purpose of the present work was to find new anticancer molecules from a natural source. We utilized chromatographic methods to isolate compounds from medicinal plant Dryopteris fragrans (L.) Schott. The structure of the new compounds was determined by spectroscopic and spectrometric data (1D NMR, 2D NMR, and EMI-MS). Their anti-proliferation effects against five human cancer cell lines including A549, MCF7, HepG2, HeLa, and PC-3 were evaluated by CCK-8 andlactate dehydrogenase (LDH) assay. A new sesquiterpene, (7S, 10S)-2,3-dihydroxy-calamenene-15-carboxylic acid methyl ester (1), and two known compounds (2 and 3) were isolated. The new sesquiterpene was named dryofraterpene A and significantly inhibited cancer cell proliferation without any obvious necrosis below a 10 µM concentration. In conclusion, a novel anticancer sesquiterpene together with two known compounds was isolated, which might be a promising lead compound for the treatment of cancer.

PP2Acα positively regulates the termination of liver regeneration in mice through the AKT/GSK3ß/Cyclin D1 pathway.

BACKGROUND & AIMS: Liver injury triggers a highly organized and ordered liver regeneration (LR) process. Once regeneration is complete, a stop signal ensures that the regenerated liver is an appropriate functional size. The inhibitors and stop signals that regulate LR are unknown, and only limited information is available about these mechanisms. METHODS: A 70% partial hepatectomy (PH) was performed in hepatocyte-specific PP2Acα-deleted (PP2Acα(-/-)) and control (PP2Acα(+/+)) mice. LR was estimated by liver weight, serum alanine aminotransferase (ALT) and aspartate aminotransferase (AST) levels and cell proliferation, and the related cellular signals were analyzed. RESULTS: We found that the catalytic subunit of PP2A was markedly upregulated during the late stage of LR. PP2Acα(-/-) mice showed prolonged LR termination, an increased liver size compared to the original mass and lower levels of serum ALT and AST compared with control mice. In these mice, cyclin D1 protein levels, but not mRNA levels, were increased. Mechanistically, AKT activated by the loss of PP2Acα inhibited glycogen synthase kinase 3ß (GSK3ß) activity, which led to the accumulation of cyclin D1 protein and accelerated hepatocyte proliferation at the termination stage. Treatment with the PI3K inhibitor wortmannin at the termination stage was sufficient to inhibit cyclin D1 accumulation and hepatocyte proliferation. CONCLUSIONS: PP2Acα plays an essential role in the proper termination of LR via the AKT/GSK3ß/Cyclin D1 pathway. Our findings enrich the understanding of the molecular mechanism that controls the termination of LR and provides a potential therapeutic target for treating liver injury.

Characterization and application of droplet spray ionization for real-time reaction monitoring.

RATIONALE: The ionization source for real-time reaction monitoring has attracted tremendous interest in recent years. We have previously reported a reliable approach in which droplet spray ionization (DSI) was used for monitoring chemical reactions in real-time. Herein, we systematically investigated the characterization and application of DSI for real-time reaction monitoring. METHODS: Analyte ions are generated by loading a sample solution onto a corner of a microscope cover glass positioned in front of the MS inlet and applying a high voltage to the sample. The tolerance to positioning, solvent effect, spray angle and spray time were investigated. Extension to real-time monitoring of macromolecule reactions was also demonstrated by the charge state change of cytochrome c in the presence of acetic acid. RESULTS: The corner could be positioned within an area of approximately 10 × 6 × 5 mm (x, y, z) in front of the MS inlet. The broad polarities of solvents from methanol to PhF were suitable for DSI. It featured monitoring real-time changes in reactions on the time scale of seconds to minutes. A real-time charge state change of cytochrome c was captured. CONCLUSIONS: DSI-MS features ease of use, durability of the spray platform and reusability of the ion source. Eliminating the need for a sample transport capillary, DSI opens a new avenue for the in situ analysis and real-time monitoring of short-lived key reaction intermediates even at subsecond dead times. Copyright © 2016 John Wiley & Sons, Ltd.

Chemical Components and Pharmacological Activities of Terpene Natural Products from the Genus Paeonia.

Paeonia is the single genus of ca. 33 known species in the family Paeoniaceae, found in Asia, Europe and Western North America. Up to now, more than 180 compounds have been isolated from nine species of the genus Paeonia, including terpenes, phenols, flavonoids, essential oil and tannins. Terpenes, the most abundant naturally occurring compounds, which accounted for about 57% and occurred in almost every species, are responsible for the observed in vivo and in vitro biological activities. This paper aims to give a comprehensive overview of the recent phytochemical and pharmacological knowledge of the terpenes from Paeonia plants, and enlighten further drug discovery research.

Proteomics of methyl jasmonate induced defense response in maize leaves against Asian corn borer.

BACKGROUND: Jasmonic acid (JA) and methyl jasmonate (MeJA) regulate plant development, resistance to stress, and insect attack by inducing specific gene expression. However, little is known about the mechanism of plant defense against herbivore attack at a protein level. Using a high-resolution 2-D gel, we identified 62 MeJA-responsive proteins and measured protein expression level changes. RESULTS: Among these 62 proteins, 43 proteins levels were increased while 11 proteins were decreased. We also found eight proteins uniquely expressed in response to MeJA treatment. Data are available via ProteomeXchange with identifier PXD001793. The proteins identified in this study have important biological functions including photosynthesis and energy related proteins (38.4%), protein folding, degradation and regulated proteins (15.0%), stress and defense regulated proteins (11.7%), and redox-responsive proteins (8.3%). The expression levels of four important genes were determined by qRT-PCR analysis. The expression levels of these proteins did not correlate well with their translation levels. To test the defense functions of the differentially expressed proteins, expression vectors of four protein coding genes were constructed to express in-fusion proteins in E. coli. The expressed proteins were used to feed Ostrinia furnacalis, the Asian corn borer (ACB). Our results demonstrated that the recombinant proteins of pathogenesis-related protein 1 (PR1) and thioredoxin M-type, chloroplastic precursor (TRXM) showed the significant inhibition on the development of larvae and pupae. CONCLUSIONS: We found MeJA could not only induce plant defense mechanisms to insects, it also enhanced toxic protein production that potentially can be used for bio-control of ACB.

[Quality standard study on Tibetan medicine Gentianae Szechenyii Flos].

In order to efficiently control the quality of the Tibetan medicine Gentianae Szechenyii Flos, the quality standard was established in this study. The tests of water content, total ash and ethanol-soluble extractives of the crude drugs were carried out based on the methods recorded in appendix of Chinese Pharmacopeia (2010 edition, volume 1). The TLC method was established by using reference drug and gentiournoside A as reference substance, and a mixture of ethyl acetate-methanol-water-formic acid (7: 1.5: 1: 0.2) as the developing solvent system on silica gel G TLC plate. The content of gentiournoside A was assayed by HPLC on a Ultimate XB-C18 (4.6 mm x 250 mm, 5 µm) column, using methanol-water (0.02% phosphoric acid) (52:48) as the mobile phase at a flow rate of 1.0 mL x min(-1). The column temperature is 25 degrees C and the detection wavelength is at 240 nm. As a result, gentiournoside A and the other constituents were separated and presented the same fluorescence light comparing with the reference substance on TLC detected under the UV light(366 nm). The methodology validation for the assay of gentiournoside A showed that it was in a good linear correlation in the range of 10.01-400.32 mg x L(-1) with the regression equation of Y = 1 539.5X - 33.339 (r = 0.999 7), and the average recovery was 99.68% (RSD 1.92%). The mass fractions of gentiournoside A, water content, ethanol-soluble extractives of 19 batches samples were varied in the ranges of 14.48-31.51 mg x g(-1), 11.25% -12.74% and 24.21% - 31.60%, respectively, and total ash was 4.64% - 6.12% detected from 10 batches samples. The recommended standards of quantitative indexes are that the mass fractions of gentiournoside A and extractives are not less than 15.0 mg x g(-1) (1.5%) and 21.0%, respectively; the water and total ash are not more than 13.0% and 6.0%, respectively.

Compounds from Dryopteris fragrans (L.) Schott with cytotoxic activity.

One new coumarin, dryofracoumarin A (1), and eight known compounds 2-9 were isolated from Dryopteris fragrans (L.) Schott. Their structures were established on the basis of extensive spectroscopic data analyses and comparison with reported spectroscopic data. The new compound 1 was determined to be 8-hydroxyl-4-isopropyl-7-methyl-6-methyl-2H-benzopyran-2-one. Two dimers, trans- and cis-3-(3,4-dimethoxyphen-yl)-4-[(E)-3,4-dimethoxystyryl]cyclohex-1-ene (compounds 8 and 9), were isolated from the Dryopteris genus for the first time. The other six were esculetin (2), isoscopoletin (3), methylphlorbutyrophenone (4), aspidinol (5), albicanol (6) and (E)-4-(3,4-dimethoxyphen-yl)but-3-en-1-ol (7). All compounds were evaluated for their cytotoxic effects by the MTT assay. Compounds 2, 3, 8 and 9 showed significantly cytotoxic effects against three cell lines (A549, MCF7 and HepG2), 1 and 5 against two cell lines (A549 and MCF7), and 6 against one cell line (MCF7). Their IC50 values ranged between 2.73 ± 0.86 µM and 24.14 ± 3.12 µM. These active compounds might be promising lead compounds for the treatment of cancer.