Isatis tinctoria L. (Woad): A Review of its Botany, Ethnobotanical Uses, Phytochemistry, Biological Activities, and Biotechnological Studies

The dawn of ethnomicrobiology: an interdisciplinary research field on interactions between humans and microorganisms

BACKGROUND

Ethnobiologists commonly analyze local knowledge systems related to plants, animals, fungi, and ecosystems. However, microbes (bacteria, yeasts, molds, viruses, and other organisms), often considered invisible in their interactions with humans, are often neglected. Microorganisms were the earliest life forms on Earth, and humans have interacted with them throughout history. Over time, humans have accumulated ecological knowledge about microbes through attributes such as smell, taste, and texture that guide the management of contexts in which microorganisms evolve. These human-microbe interactions are, in fact, expressions of biocultural diversity. Thus, we propose that ethnomicrobiology is a distinct interdisciplinary field within ethnobiology that examines the management practices and knowledge surrounding human-microbe interactions, along with the theoretical contributions that such an approach can offer.

METHODS

We reviewed scientific journals, books, and chapters exploring human-microbe relationships. Our search included databases such as Web of Science, Scopus, Google Scholar, and specific journal websites, using keywords related to ethnomicrobiology and ethnozymology. To categorize activities involving deliberate human-microbial interactions, we examined topics such as fermentation, pickling, food preservation, silaging, tanning, drying, salting, smoking, traditional medicine, folk medicine, agricultural practices, composting, and other related practices.

RESULTS

Our research identified important precedents for ethnomicrobiology through practical and theoretical insights into human-microbe interactions, particularly in their impact on health, soil, and food systems. We also found that these interactions contribute to biodiversity conservation and co-evolutionary processes. This emerging interdisciplinary field has implications for food ecology, public health, and the biocultural conservation of hidden microbial landscapes and communities. It is essential to explore the socioecological implications of the interwoven relationships between microbial communities and humans. Equally important is the promotion of the conservation and recovery of this vast biocultural diversity, along with sustainable management practices informed by local ecological knowledge.

CONCLUSION

Recognizing the dawn of ethnomicrobiology is essential as the field evolves from a descriptive to a more theoretical and integrative biological approach. We emphasize the critical role that traditional communities have played in conserving food, agriculture, and health systems. This emerging field highlights that the future of ethnobiological sciences will focus not on individual organisms or cultures, but on the symbiosis between microorganisms and humans that has shaped invisible but often complex biocultural landscapes.

Anti-diabetes and neuroprotection potential and primary safety studies of Isatis tinctoria L. hydroalcoholic leaf extract

PURPOSE

Natural plant raw materials, previously underestimated in therapeutics, are becoming the subject of research for new applications in medicine. In our research, the hydroalcoholic extract of Isatis tinctoria leaf, rich in flavonoid compounds such as vicenin-2 and quercetin, was examined as a potential antidiabetic and neuroprotective agent.

METHODS

The effect of the extract and its main flavonoid compounds on protein glycation, alpha-glucosidase activity, and acetylcholinesterase activity was tested. In vitro, in the mouse hippocampal neuronal cell line and in vivo, using a mouse model, the safety of the extract was screened for.

RESULTS

Our experiments demonstrated significant inhibition of protein glycation, alpha-glucosidase activity, acetylcholinesterase activity, and β-amyloid aggregation by the extract, in a concentration-dependent manner. The extract had a strong reducing effect and did not exhibit cytotoxicity up to a concentration of 25 mg/mL. Intraperitoneal administration of the extract to mice did not have negative effects on body mass, locomotor activity, coordination, and liver cell integrity.

CONCLUSIONS

Our research sheds new light on this raw material and deepens knowledge of its activity. This may result in the recognition of its therapeutic effects and even in its introduction in the modern treatment of diseases characterized by pathological changes associated with hyperglycemia, oxidation, and inflammation.

2,4-Quinolinedione alkaloids: occurrence and biological activities

Natural products are an important source of chemical scaffolds that have diverse biological activities. They can be used directly or as starting templates for the development of innovative pharmaceutical agents. Among natural products, quinoline alkaloids are one of the most extensively studied groups. 2,4-Quinolinedione (2,4-QD) alkaloids, which are found in a variety of natural sources, possess valuable biological properties. This review examines the natural occurrence and bioactivities of 2,4-QD alkaloids, which have not been studied in as much depth in previous research.

Indirubin mediates adverse intestinal reactions in guinea pigs by downregulating the expression of AchE through AhR

Indirubin is the main component of the traditional Chinese medicine Indigo naturalis (IN), a potent agonist of aryl hydrocarbon receptors (AhRs). In China, IN is used to treat psoriasis and ulcerative colitis, and indirubin is used for the treatment of chronic myelogenous leukaemia. However, IN and indirubin have adverse reactions, such as abdominal pain, diarrhoea, and intussusception, and their specific mechanism is unclear.The purpose of our research was to determine the specific mechanism underlying the adverse effects of IN and indirubin. By tracking the modifications in guinea pigs after the intragastric administration of indirubin for 28 days.The results demonstrate that indirubin could accelerate bowel movements and decrease intestinal acetylcholinesterase (AchE) expression. Experiments with NCM460 cells revealed that indirubin significantly reduced the expression of AchE, and the AchE levels were increased after the silencing of AhR and re-exposure to indirubin.This study showed that the inhibition of AchE expression by indirubin plays a key role in the occurrence of adverse reactions to indirubin and that the underlying mechanism is related to AhR-mediated AchE downregulation.

Indigofera suffruticosa aerial parts extract induce G2/M arrest and ATR/CHK1 pathway in Jurkat cells

BACKGROUND

Indigofera suffruticosa Mill. is used as a folk medicine for treating patients with leukemia, however very little is known regarding the molecular mechanism of its anti-leukemic activity and the chemical profile of the active extract. The present study aimed to reveal the molecular effect of I. suffruticosa aerial parts extract (ISAE) on leukemia cells and its chemical constituents.

METHODS

Cytotoxicity of ISAE were determined by resazurin viability assay, multitox - Glo multiplex cytotoxicity assay, and Annexin V staining assay. Cell cycle profiles were revealed by propidium iodide staining assay. The effects of ISAE on G2/M arrest signaling and DNA damage were evaluated by Western blot assay and phospho-H2A.X staining assay. The chemical profile of ISAE were determined by tandem mass spectroscopy and molecular networking approach.

RESULTS

We showed that the acute lymphoblastic leukemia cell line Jurkat cell was more responsive to ISAE treatment than other leukemia cell lines. In contrast, ISAE did not induce cytotoxic effects in normal fibroblast cells. Cell cycle analysis revealed that ISAE triggered G2/M arrest in Jurkat cells in dose- and time-dependent manners. Elevation of annexin V-stained cells and caspase 3/7 activity suggested ISAE-induced apoptosis. Furthermore, ISAE alone could increase the phosphorylation of CDK1 at Y15 and activate the ATR/CHK1/Wee1/CDC25C signaling pathway. However, the addition of caffeine, a widely used ATR inhibitor to ISAE, reduced the phosphorylation of ATR, CHK1, and CDK1, as well as G2/M arrest in Jurkat cells. Moreover, increased phospho-H2A.X stained cells indicated the involvement of DNA damage in the anti-leukemic effect of ISAE. Finally, qualitative analysis using UPLC-tandem mass spectroscopy and molecular networking revealed that tryptanthrin was the most abundant organoheterocyclic metabolite in ISAE. At equivalent concentrations to ISAE, tryptanthrin induced G2/M arrest of Jurkat cells, which can be prevented by caffeine.

CONCLUSIONS

ISAE causes G2/M arrest via activating ATR/CHK1/CDK1 pathway and tryptanthrin is one of the active components of ISAE. Our findings provide subtle support to the traditional use of I. suffruitcosa in leukemia management in folk medicine.

Natural colour extraction from horticultural crops, advancements, and applications-a review

The scope for natural colours is increasing because of the awareness of allergic, toxic, and hazardous reactions associated with synthetic dyes. Natural colours are extracted from sources that are naturally available, such as flora, fauna, and minerals. Nature sourced us multiple possibilities of colours with varied shades and hues that are subtle and harmonious when combined. Reasons like the instability of natural colours during industrial processing, seasonal availability of raw materials, fading of colour over time, cost of the benefit, and struggles in attaining sustainability have reduced commercialisation success as synthetic colours. Some plants that yield natural colours are also included in crop rotation practice. Natural dye extraction is a source of employment for the countrified subdivisions of poor developing countries. Indigenous technologies on natural colour extraction are available and have been practiced over the years; due to a lack of documentation and information on colour-yielding plants or products from horticultural crops, and their extraction methods, the use of natural colours is diminishing day by day. Even in recent years, emerging techniques have been adopted in research and development, and the information has not been brought together for the use of industries and allied sectors. Several modern approaches, such as Ultrasonication, microwave, enzymatic, supercritical, pressurised liquid extraction, etc., have proven to give better results in extracting natural colours. Thereby, having instantaneous information will help to go green, be eco-friendly, and effectively utilise all the resources without compromising industrial benefits. Reviewing the availability of natural colours from horticultural crops, classifications, recent trends in their extraction process, and applications in various fields will help achieve the above.

Silver and salicylic acid-chitosan nanoparticles alter indole alkaloid production and gene expression in root and shoot cultures of Isatis tinctoria and Isatis ermenekensis

Isatis spp. are well-known for their industrial significance due to natural sources of indigotin and indirubin, important indole alkaloids, used in the dye and pharmaceutical industries. In this study, silver nanoparticles (AgNP) and salicylic acid-chitosan nanoparticles (SA-CNP) were synthesized and applied to enhance the production of indigotin and indirubin in shoot and root cultures of Isatis tinctoria and Isatis ermenekensis. Different doses of AgNP and SA-CNP were administered to three-week-old shoot and root cultures, and the effects were assessed at 12, 24, and 48 h. The harvested samples were analyzed to quantify indigotin and indirubin levels. Furthermore, the expression levels of It-TSA and CYP79B2 genes, known to be involved in indole alkaloid biosynthesis, were determined. In I. tinctoria roots, the highest levels of indigotin and indirubin were observed after applying 150 mg L-1 of SA-CNP for 48 h while in I. ermenekensis shoots, indigotin and indirubin reached the maximum levels with the application of 8 mg L-1 AgNP for 48 h. NP application had no remarkable effects on the accumulation of indigotin and indirubin in I. tinctoria shoots and I. ermenekensis roots compared to controls. Additionally, shoot cultures demonstrated superior indirubin production, which significantly increased with AgNP applications. The gene expression analysis also exhibited significant correlations with the changes in indigotin and indirubin levels. The findings of this study lay the groundwork for enhancing in vitro production of indigotin and indirubin in Isatis species through NP applications, and for developing high-capacity production strategies by determining optimal dosages in scale-up studies.

Atrazine Toxicity: The Possible Role of Natural Products for Effective Treatment

There are various herbicides which were used in the agriculture industry. Atrazine (ATZ) is a chlorinated triazine herbicide that consists of a ring structure, known as the triazine ring, along with a chlorine atom and five nitrogen atoms. ATZ is a water-soluble herbicide, which makes it capable of easily infiltrating into majority of the aquatic ecosystems. There are reports of toxic effects of ATZ on different systems of the body but, unfortunately, majority of these scientific reports were documented in animals. The herbicide was reported to enter the body through various routes. The toxicity of the herbicide can cause deleterious effects on the respiratory, reproductive, endocrine, central nervous system, gastrointestinal, and urinary systems of the human body. Alarmingly, few studies in industrial workers showed ATZ exposure leading to cancer. We embarked on the present review to discuss the mechanism of action of ATZ toxicity for which there is no specific antidote or drug. Evidence-based published literature on the effective use of natural products such as lycopene, curcumin, Panax ginseng, Spirulina platensis, Fucoidans, vitamin C, soyabeans, quercetin, L-carnitine, Telfairia occidentalis, vitamin E, Garcinia kola, melatonin, selenium, Isatis indigotica, polyphenols, Acacia nilotica, and Zingiber officinale were discussed in detail. In the absence of any particular allopathic drug, the present review may open the doors for future drug design involving the natural products and their active compounds.

Improvement in the Biosynthesis of Antioxidant-Active Metabolites in In Vitro Cultures of Isatis tinctoria (Brassicaceae) by Biotechnological Methods/Elicitation and Precursor Feeding

This study aimed to establish the in vitro shoot culture of Isatis tinctoria L. and its ability to produce antioxidant bioactive compounds. The Murashige and Skoog (MS) medium variants, containing different concentrations (0.1-2.0 mg/L) of benzylaminopurine (BAP) and 1-naphthaleneacetic acid (NAA) were tested. Their influence on the growth of biomass, accumulation of phenolic compounds, and antioxidant potential was evaluated. To improve the phenolic content, agitated cultures (MS 1.0/1.0 mg/L BAP/NAA) were treated with different elicitors, including the following: Methyl Jasmonate, CaCl₂, AgNO₃, and yeast, as well as with L-Phenylalanine and L-Tyrosine-precursors of phenolic metabolites. The total phenolic content (TPC) of hydroalcoholic extracts (MeOH 70%) obtained from the biomass grown in vitro was determined spectrophotometrically; phenolic acids and flavonoids were quantified by RP-HPLC. Moreover, the antioxidant potential of extracts was examined through the DPPH test, the reducing power, and the Fe²⁺ chelating assays. The biomass extracts obtained after 72 h of supplementation with Tyr (2 g/L), as well as after 120 and 168 h with Tyr (1 g/L), were found to be the richest in TPC (49.37 ± 0.93, 58.65 ± 0.91, and 60.36 ± 4.97 mg GAE/g extract, respectively). Whereas among the elicitors, the highest TPC achieved was with CaCl₂ (20 and 50 mM 24 h), followed by MeJa (50 and 100 µM, 120 h). The HPLC of the extracts led to the identification of six flavonoids and nine phenolic acids, with vicenin-2, isovitexin, syringic, and caffeic acids being the most abundant compounds. Notably, the amount of all flavonoids and phenolic acids detected in the elicited/precursor feeding biomass was higher than that of the leaves of the parental plant. The best chelating activity was found with the extract of biomass fed with Tyrosine 2 g/L, 72 h (IC₅₀ 0.27 ± 0.01 mg/mL), the strongest radical scavenging (DPPH test) for the extract obtained from biomass elicited with CaCl₂ 50 mM, after 24 h of incubation (25.14 ± 0.35 mg Trolox equivalents (TE)/g extract). In conclusion, the in vitro shoot culture of I. tinctoria supplemented with Tyrosine, as well as MeJa and/or CaCl₂, could represent a biotechnological source of compounds with antioxidant properties.

Anti-Atopic Effect of Isatidis Folium Water Extract in TNF-α/IFN-γ-Induced HaCaT Cells and DNCB-Induced Atopic Dermatitis Mouse Model

Isatidis folium or Isatis tinctoria L. is a flowering plant of the Brassicaceae family, commonly known as woad, with an ancient and well-documented history as an indigo dye and medicinal plant. This study aimed to evaluate the anti-atopic dermatitis (AD) effects of Isatidis folium water extract (WIF) using a 2,4-dinitrochlorobenzene (DNCB)-induced AD-like mouse model and to investigate the underlying mechanism using tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ)-activated HaCaT cells. Oral administration of WIF reduced spleen weight, decreased serum IgE and TNF-α levels, reduced epidermal and dermal thickness, and inhibited eosinophil and mast cell recruitment to the dermis compared to DNCB-induced control groups. Furthermore, oral WIF administration suppressed extracellular signal-regulated kinase and p38 mitogen-activated protein kinase protein expression levels, p65 translocation from the cytoplasm to the nucleus, and mRNA expression of TNF-α, IFN-γ, interleukin (IL)-6, and IL-13 in skin lesion tissues. In HaCaT cells, WIF suppressed the production of regulated upon activation, normal T cell expressed and secreted (RANTES), thymus and activation-regulated chemokine (TARC), macrophage-derived chemokine (MDC), MCP-1, and MIP-3a, which are inflammatory cytokines and chemokines related to AD, and inhibited the mRNA expression of RANTES, TARC, and MDC in TNF-α/IFN-γ-stimulated HaCaT cells. Overall, the results revealed that WIF ameliorated AD-like skin inflammation by suppressing proinflammatory cytokine and chemokine production via nuclear factor-κB pathway inhibition, suggesting WIF as a potential candidate for AD treatment.

Research progress on antiviral constituents in traditional Chinese medicines and their mechanisms of action

CONTEXT

Viruses have the characteristics of rapid transmission and high mortality. At present, western medicines still lack an ideal antiviral. As natural products, many traditional Chinese medicines (TCM) have certain inhibitory effects on viruses, which has become the hotspot of medical research in recent years.

OBJECTIVE

The antiviral active ingredients and mechanisms of TCM against viral diseases was studied in combination with the pathogenesis of viral diseases and antiviral effects.

MATERIALS AND METHODS

English and Chinese literature from 1999 to 2021 was collected from databases including Web of Science, PubMed, Elsevier, Chinese Pharmacopoeia 2020 (CP), and CNKI (Chinese). Traditional Chinese medicines (TCM), active ingredients, antiviral, mechanism of action, and anti-inflammatory effect were used as the key words.

RESULTS

The antiviral activity of TCM is clarified to put forward a strategy for discovering active compounds against viruses, and provide reference for screening antivirus drugs from TCM. TCM can not only directly kill viruses and inhibit the proliferation of viruses in cells, but also prevent viruses from infecting cells and causing cytophilia. It can also regulate the human immune system, enhance human immunity, and play an indirect antiviral role.

DISCUSSION AND CONCLUSION

Based on the experimental study and antiviral mechanism of TCM, this paper can provide analytical evidence that supports the effectiveness of TCM in treating virus infections, as well as their mechanisms against viruses. It could be helpful to provide reference for the research and development of innovative TCMs with multiple components, multiple targets and low toxicity.

A focused natural compound screen reveals senolytic and senostatic effects of Isatis tinctoria

Natural products and their derivatives historically represent alternatives to conventional synthetic molecules for pharmacotherapy, ranging from cancer chemotherapeutics to cosmetic ingredients that exert anti-aging activities. Cellular senescence is considered a main driver of skin aging, yet natural products that target skin senescence in a specific manner are not thoroughly explored. Here, we performed a focused compound screen to identify natural products that exert anti-senescence effects. We found that Isatis tinctoria, woad extracts, displayed a senolytic effect on senescent human skin fibroblasts. Furthermore, treatment with woad extracts attenuated the expression of pro-inflammatory senescence-associated secretory phenotype (SASP), showing a senostatic activity. Intriguingly, woad extracts displayed only a marginal cytotoxic effect toward senescent human lung fibroblasts. Thus, our results reveal the potential activities of woad extracts for targeting skin senescence and suggest that woad extracts could be an attractive ingredient for cosmetics to prevent skin aging.

Hydroalcoholic Leaf Extract of Isatis tinctoria L. via Antioxidative and Anti-Inflammatory Effects Reduces Stress-Induced Behavioral and Cellular Disorders in Mice

Stress that can occur at different levels of a person’s life can cause and exacerbate various diseases. Oxidative stress and inflammation underlie this process at the cellular level. There is an urgent need to identify new and more effective therapeutic targets for the treatment of stress-induced behavioral disorders and specific drugs that affect these targets. Isatis tinctoria L. is a herbaceous species in the Brassicaceae family. Due to its potential antioxidant, nitric oxide- (NO-) inhibiting, anti-inflammatory, and neuroprotective properties, I. tinctoria could be used to treat depression, anxiety, and stress resistance. Hence, the present study is aimed at delineating whether administration of I. tinctoria leaf extract may improve stress-induced disorders in mice. A set of four behavioral tests was selected that together are suitable for phenotyping acute restraint stress-associated behaviors in mice, namely locomotor activity, social integration, dark/light box, and splash tests. The plasma and brains were collected. A brain-derived neurotrophic factor, tumor necrosis factor-alpha, C-reactive protein, corticosterone, NO, reactive oxygen species levels, superoxide dismutase and catalase activity, and ferric-reducing antioxidant power were measured. In mice stressed by immobilization, decreased locomotor activity, anxiety-like behavior, and contact with other individuals were observed, as well as increased oxidative stress and increased levels of nitric oxide in the brain and plasma C-reactive protein. A single administration of I. tinctoria leaf extract was able to reverse the behavioral response to restraint by a mechanism partially dependent on the modulation of oxidative stress, neuroinflammation, and NO reduction. In conclusion, Isatis tinctoria hydroalcoholic leaf extract can reduce stress-induced behavioral disturbances by regulating neurooxidative, neuronitrosative, and neuroimmune pathways. Therefore, it could be recommended for further research on clinical efficacy in depression and anxiety disorder treatment.

Identification and characterization of two Isatis indigotica O-methyltransferases methylating C-glycosylflavonoids

Isatis indigotica accumulates several active substances, including C-glycosylflavonoids, which have important pharmacological activities and health benefits. However, enzymes catalyzing the methylation step of C-glycosylflavonoids in I. indigotica remain unknown. In this study, three O-methyltransferases (OMTs) were identified from I. indigotica that have the capacity for O-methylation of the C-glycosylflavonoid isoorientin. The Type II OMTs IiOMT1 and IiOMT2 efficiently catalyze isoorientin to form isoscoparin, and decorate one of the aromatic vicinal hydroxyl groups on flavones and methylate the C6, C8, and 3'-hydroxyl positions to form oroxylin A, wogonin, and chrysoeriol, respectively. However, the Type I OMT IiOMT3 exhibited broader substrate promiscuity and methylated the C7 and 3'-hydroxyl positions of flavonoids. Further site-directed mutagenesis studies demonstrated that five amino acids of IiOMT1/IiOMT2 (D121/D100, D173/D149, A174/A150R, N200/N176, and D248/D233) were critical residues for their catalytic activity. Additionally, only transient overexpression of Type II OMTs IiOMT1 and IiOMT2 in Nicotiana benthamiana significantly increased isoscoparin accumulation, indicating that the Type II OMTs IiOMT1 and IiOMT2 could catalyze the methylation step of C-glycosylflavonoid, isoorientin at the 3'-hydroxyl position. This study provides insights into the biosynthesis of methylated C-glycosylflavonoids, and IiOMTs could be promising catalysts in the synthesis of bioactive compounds.

Desorption Electrospray Ionization Mass Spectrometry Imaging Illustrates the Quality Characters of Isatidis Radix

For a long history, herbal medicines have made significant contributions to human health all around the world. However, the exploration of an effective approach to illustrate their inner quality remains a challenge. So, it is imperative to develop new methods and technologies to characterize and identify quality markers of herbal medicines. Taking Isatidis Radix, the dried root of Isatis indigotica as an example, desorption electrospray ionization (DESI), in combination with quadrupole-time-of-flight mass spectrometry (Q-TOF/MS), was applied in this work for the first time to reveal the comprehensive spatial distribution of metabolites and, further, to illustrate quality characters of this herbal medicine. After simple pretreatment, 102 metabolites including alkaloids, sulfur-containing compounds, phenylpropanoids, nucleosides, amino acids, organic acids, flavonoids, phenols, terpenes, saccharides, peptides, and sphingolipids were characterized, some of which were successfully localized and visualized in the transverse section of the root. Based on the ion images, samples with different quality characters were distinguished unambiguously by the pattern recognition method of orthogonal partial least squares discrimination analysis (OPLS-DA). Simultaneously, 11 major influencing components exerting higher ion intensities in superior samples were identified as the potential quality markers of Isatidis Radix. Desorption electrospray ionization (DESI) mass spectrometry imaging (MSI), together with chemometric analysis could not only improve the understanding of the plant biology of herbal medicines but also be beneficial in the identification of quality markers, so as to carry out better quality control of herbal medicines.

Functional Characterization of UDP-Glycosyltransferases Involved in Anti-viral Lignan Glycosides Biosynthesis in Isatis indigotica

Isatis indigotica is a popular herbal medicine with its noticeable antiviral properties, which are primarily due to its lignan glycosides such as lariciresinol-4-O-β-D-glucoside and lariciresinol-4,4'-bis-O-β-D-glucosides (also called clemastanin B). UDP-glucose-dependent glycosyltransferases are the key enzymes involved in the biosynthesis of these antiviral metabolites. In this study, we systematically characterized the UGT72 family gene IiUGT1 and two UGT71B family genes, IiUGT4 and IiUGT71B5a, with similar enzymatic functions. Kinetic analysis showed that IiUGT4 was more efficient than IiUGT1 or IiUGT71B5a for the glycosylation of lariciresinol. Further knock-down and overexpression of these IiUGTs in I. indigotica's hairy roots indicates that they play different roles in planta: IiUGT71B5a primarily participates in the biosynthesis of coniferin not pinoresinol diglucoside, and IiUGT1 primarily participates in the biosynthesis of pinoresinol diglucoside, while IiUGT4 is responsible for the glycosylation of lariciresinol and plays a dominant role in the biosynthesis of lariciresinol glycosides in I. indigotica. Analysis of the molecular docking and site-mutagenesis of IiUGT4 have found that key residues for its catalytic activity are H373, W376, E397, and that F151 could be associated with substrate preference. This study elucidates the biosynthetic route of anti-viral lignan glycosides in I. indigotica, and provides the foundation for the production of anti-viral lignan glycosides via synthetic biology under the heterologous model.

Isatis tinctoria L. Leaf Extract Inhibits Replicative Senescence in Dermal Fibroblasts by Regulating mTOR-NF-κB-SASP Signaling

Senescent fibroblasts progressively deteriorate the functional properties of skin tissue. Senescent cells secrete senescence-associated secretory phenotype (SASP) factor, which causes the aging of surrounding non-senescent cells and accelerates aging in the individuals. Recent findings suggested the senomorphic targeting of the SASP regulation as a new generation of effective therapeutics. We investigated whether Isatis tinctoria L. leaf extract (ITE) inhibited senescence biomarkers p53, p21^CDKN1A, and p16^INK4A gene expression, and SASP secretions by inhibiting cellular senescence in the replicative senescent human dermal fibroblast (RS-HDF). ITE has been demonstrated to inhibit the secretion of SASP factors in several senomorphic types by regulating the MAPK/NF-κB pathway via its inhibitory effect on mTOR. ITE suppressed the inflammatory response by inhibiting mTOR, MAPK, and IκBα phosphorylation, and blocking the nuclear translocation of NF-κB. In addition, we observed that autophagy pathway was related to inhibitory effect of ITE on cellular senescence. From these results, we concluded that ITE can prevent and restore senescence by blocking the activation and secretion of senescence-related factors generated from RS-HDFs through mTOR-NF-κB regulation.

In Vitro Anthelmintic Activity of Isatis tinctoria Extracts against Ewes' Gastrointestinal Nematodes (GINs), a Possible Application for Animal Welfare

Sheep gastrointestinal nematode (GIN) infestation represents a limiting factor for sheep farming and milk production in Italy. The development of anthelmintic resistance to conventionally used drugs suggests the path towards the use of natural remedies as a possible alternative. The purpose of this study is to evaluate the in vitro anthelmintic efficacy of the hydroalcoholic extracts of basal leaves (It-BL), cauline leaves (It-CL) and flowers (It-F) of Isatis tinctoria (Brassicaceae), a spontaneous Sicilian species renowned as an important source of bioactive compounds. The dry extracts of the different parts of the plant were tested using the egg hatch test (EHT) in vitro to verify the efficacy against ovine GIN at different concentrations (1.00, 0.5, 0.25, 0.125 mg/mL). Thiabendazole and deionized water were used as positive and negative controls, respectively. The results obtained from EHT indicated that all the I. tinctoria extracts were highly effective (p < 0.0001) in inhibiting egg hatching within 48 h of exposure. The in vitro inhibitory effect was never less than 84% in all doses tested, and it was only slightly lower than the standard drug thiabendazole (95.6%). The current study documents the anthelmintic activity of I. tinctoria against sheep’s GIN, suggesting its application as alternative natural method to limit the use of antiparasitic drugs.

Computational Workflow to Study the Diversity of Secondary Metabolites in Fourteen Different Isatis Species

The screening of real features among thousands of ions remains a great challenge in the study of metabolomics. In this research, a workflow designed based on the MetaboFR tool and “feature-rating” rule was developed to screen the real features in large-scale data analyses. Seventy-four reference standards were used to test the feasibility, with 83.21% of real features being obtained after MetaboFR processing. Moreover, the full workflow was applied for systematic characterization of 14 species of the genus Isatis, with the result that 87.72% of real features were retained and 69.19% of the in-source fragments were removed. To gain insights into metabolite diversity within this plant family, 1697 real features were tentatively identified, including lipids, phenylpropanoids, organic acids, indole derivatives, etc. Indole derivatives were demonstrated to be the best chemical markers with which to differentiate different species. The rare existence of indole derivatives in Isatis cappadocica (cap) and Isatis cappadocica subsp. Steveniana (capS) indicates that the biosynthesis of indole derivatives could play a key role in driving the chemical diversity and evolution of genus Isatis. Our workflow provides the foundations for the exploration of real features in metabolomics, and has the potential to reveal the chemical composition and marker metabolites of secondary metabolites in plant fields.

A Systemic Review for Ethnopharmacological Studies on Isatis indigotica Fortune: Bioactive Compounds and their Therapeutic Insights

Isatis indigotica Fortune is a biennial Chinese woad of the Cruciferae family. It is primarily cultivated in China, where it was a staple in indigo dye manufacture till the end of the 17th century. Today, I. indigotica is used primarily as a therapeutic herb in traditional Chinese medicine (TCM). The medicinal use of the plant is separated into its leaves (Da-Qing-Ye) and roots (Ban-Lan-Gen), whereas its aerial components can be processed into a dried bluish-spruce powder (Qing-Dai), following dehydration for long-term preservation. Over the past several decades, I. indigotica has been generally utilized for its heat-clearing effects and bodily detoxification in TCM, attributed to the presence of several classes of bioactive compounds, including organic acids, alkaloids, terpenoids, and flavonoids, as well as lignans, anthraquinones, glucosides, glucosinolates, sphingolipids, tetrapyrroles, and polysaccharides. This paper aims to delineate I. indigotica from its closely-related species (Isatis tinctoria and Isatis glauca) while highlighting the ethnomedicinal uses of I. indigotica from the perspectives of modern and traditional medicine. A systematic search of PubMed, Embase, PMC, Web of Science, and Google Scholar databases was done for articles on all aspects of the plant, emphasizing those analyzing the bioactivity of constituents of the plant. The various key bioactive compounds of I. indigotica that have been found to exhibit anti-inflammatory, antimicrobial, anticancer, and anti-allergic properties, along with the protective effects against neuronal injury and bone fracture, will be discussed. Collectively, the review hopes to draw attention to the therapeutic potential of I. indigotica not only as a TCM, but also as a potential source of bioactive compounds for disease management and treatment.

Potential therapeutic effect of Shufeng Jiedu capsule and its major herbs on coronavirus disease 2019 (COVID-19): A review

The outbreak and rapid spread of coronavirus disease 2019 (COVID-19) poses a huge threat to human health and social stability. Shufeng Jiedu capsule (SFJDC), a patented herbal drug composed of eight medicinal plants, is used to treat different viral respiratory tract infectious diseases. Based on its antiviral, anti-inflammatory, and immunoregulatory activities in acute lung injury, SFJDC can be effectively used as a treatment for COVID-19 patients according to the diagnosis and treatment plan issued in China and existing clinical data. SFJDC has been recommended in 15 therapeutic regimens for COVID-19 in China. This review summarizes current data on the ingredients, chemical composition, pharmacological properties, clinical efficacy, and potential therapeutic effect of SFJDC on COVID-19, to provide a theoretical basis for its anti-viral mechanism and the clinical treatment of COVID-19.

Isatis phytogenic relieved atrazine induced growth retardation, hepato-renal dysfunction, and oxidative stress in Nile tilapia

The influence of herbicides causes health and economic loss, which requires innovative solutions to sustain the aquaculture industry. In this regard, dietary isatis is included in Nile tilapia diets to relieve atrazine (ATZ)-induced growth retardation, hepato-renal dysfunction, and oxidative stress. The first and second groups offered the control diet (control), while the third and fourth groups offered the isatis supplemented diet (1%). Meantime, half of the water was replaced and mixed with ATZ (1.39 mg/L) in the second and fourth groups for 30 days. The group of fish delivered isatis had significantly enhanced FBW, WG, and SGR, while fish intoxicated with ATZ had meaningfully impaired growth behavior (p < 0.05). Further, the FCR was improved by isatis, and ATZ resulted in the worst FCR among the groups. Interestingly fish fed isatis and exposed with ATZ (88.89%) had a higher survival rate than fish exposed with ATZ without isatis feeding, and both are lower than the control (97.78%) (p < 0.05). The histological structure in the isatis-treated groups showed distinguished enhancement and branching of the intestinal villi. The intestine of ATZ-treated fish revealed damage and inflammatory cell infiltration in the intestinal mucosa with separation of lining epithelium. Generally, fish fed isatis and intoxicated with ATZ had lower uric acid, urea, creatinine, ALT, and AST and higher total protein, globulin, and albumin than fish exposed with ATZ without feeding with isatis (p < 0.05). Markedly, fish-fed isatis had the highest SOD, CAT, GPx, and the lowest MDA level compared to the other groups (p < 0.05). Meanwhile, fish exposed with ATZ had the worst SOD, CAT, GPx, and the highest MDA level compared to the other groups (p < 0.05). In summary, dietary isatis relieved ATZ induced growth retardation, hepato-renal dysfunction, and oxidative stress in Nile tilapia.

Isatis indigotica: from (ethno) botany, biochemistry to synthetic biology

Isatis indigotica Fort. (Chinese woad) is a species with an ancient and well-documented history as an indigo dye and medicinal plant. It is often confused with Isatis tinctoria L. (European woad), a medicinal plant in Europe. Here, the differences between I. indigotica and I. tinctoria are systematically described. The usage development history, clinical applications and pharmacological activities, and chemical components of I. indigotica are also summarized. Lignans, indole alkaloids, and their corresponding derivatives have been identified as the major active ingredients of I. indigotica and are associated with anti-viral, anti-inflammatory, anti-cancer, and other health-promoting activities. Notable progress has been made in understanding the biosynthetic pathway and regulation mechanism of lignans and indole alkaloids in I. indigotica, the results from which should facilitate the process of targeted metabolic engineering or synthetic biology. Moreover, multiple biotechnology methods such as polyploid breeding and genetic engineering have been used with I. indigotica to result in, for example, greater yields, higher levels of bioactive component accumulation, and enhanced stress tolerance to salt, drought, and insects. Some issues require additional analyses, and suggestions for future research on I. indigotica are also discussed.

Synthetic Tryptanthrin Derivatives Induce Cell Cycle Arrest and Apoptosis via Akt and MAPKs in Human Hepatocellular Carcinoma Cells

Trytanthrin, found in Ban-Lan-Gen, is a natural product containing an indoloquinazoline moiety and has been shown to possess anti-inflammatory and anti-viral activities. Chronic inflammation and hepatitis B are known to be associated with the progression of hepatocellular carcinoma (HCC). In this study, a series of tryptanthrin derivatives were synthesized to generate potent anti-tumor agents against HCC. This effort yielded two compounds, A1 and A6, that exhibited multi-fold higher cytotoxicity in HCC cells than the parent compound. Flow cytometric analysis demonstrated that A1 and A6 caused S-phase arrest and downregulated the expression of cyclin A1, B1, CDK2, and p-CDC2. In addition to inducing caspase-dependent apoptosis, A1 and A6 exhibited similar regulation of the phosphorylation or expression of multiple signaling targets, including Akt, NF-κB, and mitogen-activated protein kinases. The anti-tumor activities of A1 and A6 were also attributable to the generation of reactive oxygen species, accompanied by an increase in p-p53 levels. Therefore, A1 and A6 have potential clinical applications since they target diverse aspects of cancer cell growth in HCC.

Integrative analyses of targeted metabolome and transcriptome of Isatidis Radix autotetraploids highlighted key polyploidization-responsive regulators

Background

Isatidis Radix, the root of Isatis indigotica Fort. (Chinese woad) can produce a variety of efficacious compound with medicinal properties. The tetraploid I. indigotica plants exhibit superior phenotypic traits, such as greater yield, higher bioactive compounds accumulation and enhanced stress tolerance. In this study, a comparative transcriptomic and metabolomic study on Isatidis Radix autotetraploid and its progenitor was performed.

Results

Through the targeted metabolic profiling, 283 metabolites were identified in Isatidis Radix, and 70 polyploidization-altered metabolites were obtained. Moreover, the production of lignans was significantly increased post polyploidization, which implied that polyploidization-modulated changes in lignan biosynthesis. Regarding the transcriptomic shift, 2065 differentially expressed genes (DEGs) were identified as being polyploidy-responsive genes, and the polyploidization-altered DEGs were enriched in phenylpropanoid biosynthesis and plant hormone signal transduction. The further integrative analysis of polyploidy-responsive metabolome and transcriptome showed that 1584 DEGs were highly correlated with the 70 polyploidization-altered metabolites, and the transcriptional factors TFs-lignans network highlighted 10 polyploidy-altered TFs and 17 fluctuated phenylpropanoid pathway compounds.

Conclusions

These results collectively indicated that polyploidization contributed to the high content of active compounds in autotetraploid roots, and the gene–lignan pathway network analysis highlighted polyploidy–responsive key functional genes and regulators.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12864-021-07980-w.

Microscopic Mass Spectrometry Imaging Reveals the Distribution of Phytochemicals in the Dried Root of Isatis tinctoria

The dried root of Isatis tinctoria L. (Brassicaceae) is one of the most popular traditional Chinese medicines with well-recognized prevention and treatment effects against viral infections. Above 300 components have been isolated from this herb, but their spatial distribution in the root tissue remains unknown. In recent years, mass spectrometry imaging (MSI) has become a booming technology for capturing the spatial accumulation and localization of molecules in fresh plants, animal, or human tissues. However, few studies were conducted on the dried herbal materials due to the obstacles in cryosectioning. In this study, distribution of phytochemicals in the dried root of Isatis tinctoria was revealed by microscopic mass spectrometry imaging, with application of atmospheric pressure-matrix-assisted laser desorption/ionization (AP-MALDI) and ion trap-time-of-flight mass spectrometry (IT-TOF/MS). After optimization of the slice preparation and matrix application, 118 ions were identified without extraction and isolation, and the locations of some metabolites in the dried root of Isatis tinctoria were comprehensively visualized for the first time. Combining with partial least square (PLS) regression, samples collected from four habitats were differentiated unambiguously based on their mass spectrometry imaging.

A Brief Overview of Potential Treatments for Viral Diseases Using Natural Plant Compounds: The Case of SARS-Cov

The COVID-19 pandemic, as well as the more general global increase in viral diseases, has led researchers to look to the plant kingdom as a potential source for antiviral compounds. Since ancient times, herbal medicines have been extensively applied in the treatment and prevention of various infectious diseases in different traditional systems. The purpose of this review is to highlight the potential antiviral activity of plant compounds as effective and reliable agents against viral infections, especially by viruses from the coronavirus group. Various antiviral mechanisms shown by crude plant extracts and plant-derived bioactive compounds are discussed. The understanding of the action mechanisms of complex plant extract and isolated plant-derived compounds will help pave the way towards the combat of this life-threatening disease. Further, molecular docking studies, in silico analyses of extracted compounds, and future prospects are included. The in vitro production of antiviral chemical compounds from plants using molecular pharming is also considered. Notably, hairy root cultures represent a promising and sustainable way to obtain a range of biologically active compounds that may be applied in the development of novel antiviral agents.

Plant Products as Inhibitors of Coronavirus 3CL Protease

Background: The ongoing COVID-19 pandemic has created an alarming situation due to extensive loss of human lives and economy, posing enormous threat to global health security. Till date, no antiviral drug or vaccine against SARS-CoV-2 has reached the market, although a number of clinical trials are under way. The viral 3-chymotrypsin-like cysteine protease (3CLpro), playing pivotal roles in coronavirus replication and polyprotein processing, is essential for its life cycle. In fact, 3CLpro is already a proven drug discovery target for SARS- and MERS-CoVs. This underlines the importance of 3CL protease in the design of potent drugs against COVID-19. Methods: We have collected one hundred twenty-seven relevant literatures to prepare the review article. PubMed, Google Scholar and other scientific search engines were used to collect the literature based on keywords, like "SARS-CoVs-3CL protease," "medicinal plant and anti-SARS-CoVs-3CL protease" published during 2003-2020. However, earlier publications related to this topic are also cited for necessary illustration and discussion. Repetitive articles and non-English studies were excluded. Results: From the literature search, we have enlisted medicinal plants reported to inhibit coronavirus 3CL protease. Some of the plants like Isatis tinctoria L. (syn. Isatis indigotica Fort.), Torreya nucifera (L.) Siebold and Zucc., Psoralea corylifolia L., and Rheum palmatum L. have exhibited strong anti-3CLpro activity. We have also discussed about the phytochemicals with encouraging antiviral activity, such as, bavachinin, psoralidin, betulinic acid, curcumin and hinokinin, isolated from traditional medicinal plants. Conclusion: Currently, searching for a plant-derived novel drug with better therapeutic index is highly desirable due to lack of specific treatment for SARS-CoV-2. It is expected that in-depth evaluation of medicinally important plants would reveal new molecules with significant potential to inhibit coronavirus 3CL protease for development into approved antiviral drug against COVID-19 in future.

A global profiling strategy using comprehensive two-dimensional liquid chromatography coupled with dual-mass spectrometry platforms: Chemical analysis of a multi-herb Chinese medicine formula as a case study

Although ultraviolet detector or mass spectrometer could be coupled with two-dimensional liquid chromatography (2DLC) to analyze complex constituents, full detection and identification of the compounds are difficult. Suffering from biased UV detection and insufficient MS data interpretation, a number of minor compounds are neglected though they are separated. In this study, we report a global chemical profiling strategy using comprehensive 2DLC coupled with dual-MS platforms, including Orbitrap-MS and QqQ-MS. It was exemplified by an 11-herb Chinese medicine formula Xiaoer-Feire-Kechuan (XFK). Firstly, constituents in XFK were separated on a CSH C₁₈ × Phenyl-Hexyl 2DLC system with a practical peak capacity of 990.5 and an orthogonality of 90.3%. Secondly, untargeted mass spectral data was collected using dd-MS² scan on an Orbitrap-MS. In total 542 peaks were detected, which was 4 times of that detected by 2DLC/UV (131 peaks). A total of 108 compounds were tentatively identified. Thirdly, targeted mass spectral data was collected for 8 characteristic substructures using neutral loss and precursor ion (NL/PRE) scan on a QqQ-MS. Extracted ion chromatogram was used to recognize minor constituents. An additional of 151 compounds were detected. Our study indicated that comprehensive 2DLC coupled with dd-MS² and NL/PRE-MS is a powerful technique for the global profiling of multi-component systems.

COVID-19 Prophylaxis Efforts Based on Natural Antiviral Plant Extracts and Their Compounds

During the time of the novel coronavirus disease 2019 (COVID-19) pandemic, it has been crucial to search for novel antiviral drugs from plants and well as other natural sources as alternatives for prophylaxis. This work reviews the antiviral potential of plant extracts, and the results of previous research for the treatment and prophylaxis of coronavirus disease and previous kinds of representative coronaviruses group. Detailed descriptions of medicinal herbs and crops based on their origin native area, plant parts used, and their antiviral potentials have been conducted. The possible role of plant-derived natural antiviral compounds for the development of plant-based drugs against coronavirus has been described. To identify useful scientific trends, VOSviewer visualization of presented scientific data analysis was used.

Mechanisms of Plant Antioxidants Action

The plant kingdom is a rich source of health-promoting compounds and has always played a fundamental role in the isolation, identification, and modification of compounds able to perform several properties on live organisms. Among them, the so-called “antioxidants” have a major potentiality to increase human wellness. Antioxidants are important components in the signaling and defense mechanisms in some plants, where they are precursors of compounds of greater complexity, the modulator of plant growth, and the defensive system against pathogenic organisms and predators. The extraordinary variety of chemical structure and substitution present in the different plant antioxidants make them an inestimable source of interesting compounds, with the ability to counter reactive oxygen/nitrogen species (ROS/RNS) and to stimulate the activation of signal cascade inside the cells. The mechanisms by which antioxidants detoxify these dangerous compounds are complex and involve either direct or indirect interaction with radicals. Antioxidants inhibit or quench free radical reactions mainly based on their reducing capacity or hydrogen atom-donating capacity, their solubility, and chelating properties. Moreover, their ability to modulate key metabolic enzymes and activate/block gene transcription also has remarkable importance.

Therapeutic potential of medicinal plants against COVID-19: The role of antiviral medicinal metabolites

There are numerous trials underway to find treatment for the COVID-19 through testing vaccines as well as existing drugs. Apart from the many synthetic chemical compounds, plant-based compounds could provide an array of \suitable candidates for testing against the virus. Studies have confirmed the role of many plants against respiratory viruses when employed either as crude extracts or their active ingredients in pure form. The purpose of this review article is to highlight the importance of phytomedicine against COVID-19. The main aim is to review the mechanistic aspects of most important phytochemical compounds that have showed potential against coronaviruses. Glycyrrhizin from the roots of Glycyrrhiza glabra has shown promising potential against the previously epidemic coronavirus, SARS-CoV. Other important plants such as Artemisia annua, Isatis indigotica, Lindera aggregate, Pelargonium sidoides, and Glychirrhiza spp. have been employed against SARS-CoV. Active ingredients (e.g. emodin, reserpine, aescin, myricetin, scutellarin, apigenin, luteolin, and betulonic acid) have shown promising results against the coronaviruses. Phytochemicals have demonstrated activity against the coronaviruses through mechanisms such as viral entry inhibition, inhibition of replication enzymes and virus release blockage. However, compared to synthetic drugs, phytomedicine are mechanistically less understood and should be properly evaluated before application. Nonetheless, phytochemicals reduce the tedious job of drug discovery and provide a less time-consuming alternative for drug testing. Therefore, along with other drugs currently tested against COVID-19, plant-based drugs should be included for speedy development of COVID-19 treatment.