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The COVID-19 pandemic continues unabated, emphasizing the need for additional antiviral treatment options to prevent hospitalization and death of patients infected with SARS-CoV-2. The papain-like protease (PLpro) domain is part of the SARS-CoV-2 non-structural protein (nsp)-3, and represents an essential protease and validated drug target for preventing viral replication. PLpro moonlights as a deubiquitinating (DUB) and deISGylating enzyme, enabling adaptation of a DUB high throughput (HTS) screen to identify PLpro inhibitors. Drug repurposing has been a major focus through the COVID-19 pandemic as it may provide a fast and efficient route for identifying clinic-ready, safe-in-human antivirals. We here report our effort to identify PLpro inhibitors by screening the ReFRAME library of 11,804 compounds, showing that none inhibit PLpro with any reasonable activity or specificity to justify further progression towards the clinic. We also report our latest efforts to improve piperidine-scaffold inhibitors, 5c and 3k, originally developed for SARS-CoV PLpro. We report molecular details of binding and selectivity, as well as in vitro absorption, distribution, metabolism and excretion (ADME) studies of this scaffold. A co-crystal structure of SARS-CoV-2 PLpro bound to inhibitor 3k guides medicinal chemistry efforts to improve binding and ADME characteristics. We arrive at compounds with improved and favorable solubility and stability characteristics that are tested for inhibiting viral replication. Whilst still requiring significant improvement, our optimized small molecule inhibitors of PLpro display decent antiviral activity in an in vitro SARS-CoV-2 infection model, justifying further optimization.

Introduction Methods for assessing the quality of herbal medicine preparations have advanced significantly in recent years in conjunction with increases in herbal medicine use and reports of adulteration and contamination. Objective This study examined the quality of analgesic and anti-inflammatory herbal medicine preparations available on the Australian market by detecting the presence of listed ingredients, adulterants and contaminants. Methods Forty-nine analgesic and anti-inflammatory herbal medicine preparations were randomly sourced from Australian capital cities. They were audited using a dual approach of liquid chromatography-mass spectrometry (LC–MS) combined with next-generation DNA sequencing. Once screened, a comparison of listed ingredients with verified ingredients was conducted to determine the accuracy of labelling, and the extent of adulteration and contamination. Results Twenty-six of 49 (53%) herbal medicines were adulterated or contaminated with undeclared ingredients. LC–MS revealed the presence of pharmaceutical adulterants including atropine and ephedrine. DNA sequencing uncovered concerning levels of herbal substitution, adulteration and contamination, including the use of fillers (alfalfa, wheat and soy), as well as pharmacologically relevant species (Centella asiatica, Panax ginseng, Bupleurum and Passiflora). Pig/boar and bird DNA was found in some preparations, inferring substandard manufacturing practices. Of the 26 contaminated samples, 19 (73%) were manufactured in Australia, and 7 (27%) were imported from other countries (6 from China, 1 from New Zealand). In 23 of 49 (47%) herbal medicine samples, no biological ingredients were detected at all. These were predominantly pain and anti-inflammatory preparations such as glucosamine and eicosapentaenoic and docosahexaenoic acids found in krill and fish oils, so DNA would not be expected to survive the manufacturing process. Conclusion The high level of contamination and substitution of he

Use of herbal medicines and supplements by consumers to prevent or treat disease, particularly chronic conditions continues to grow, leading to increased awareness of the minimal regulation standards in many countries. Fraudulent, adulterated and contaminated herbal and traditional medicines and dietary supplements are a risk to consumer health, with adverse effects and events including overdose, drug-herb interactions and hospitalisation. The scope of the risk has been difficult to determine, prompting calls for new approaches, such as the combination of DNA metabarcoding and mass spectrometry used in this study. Here we show that nearly 50% of products tested had contamination issues, in terms of DNA, chemical composition or both. Two samples were clear cases of pharmaceutical adulteration, including a combination of paracetamol and chlorpheniramine in one product and trace amounts of buclizine, a drug no longer in use in Australia, in another. Other issues include the undeclared presence of stimulants such as caffeine, synephrine or ephedrine. DNA data highlighted potential allergy concerns (nuts, wheat), presence of potential toxins (Neem oil) and animal ingredients (reindeer, frog, shrew), and possible substitution of bird cartilage in place of shark. Only 21% of the tested products were able to have at least one ingredient corroborated by DNA sequencing. This study demonstrates that, despite current monitoring approaches, contaminated and adulterated products are still reaching the consumer. We suggest that a better solution is stronger pre-market evaluation, using techniques such as that outlined in this study.

Global consumption of complementary and alternative medicines, including herbal medicines, has increased substantially, and recent reports of adulteration demonstrate the need for high throughput and extensive pharmacovigilance to ensure product safety and quality. Three different standard reference materials and five previously analyzed herbal medicines have been used as a proof of concept for the application of adulteration/contamination screening using a Direct Sample Analysis (DSA) ion source with TOF MS on the Perkin Elmer AxION 2 TOF. This technique offers the advantages of minimum sample preparation, rapid analysis, and mass accuracies of 5 ppm. The DSA TOF analysis correlates well with the previous analysis on the initial sample set (which found undeclared herbal ingredients), with the added advantage of detecting previously untargeted compounds, including species-specific flavonoids and alkaloids. The rapid analysis using the DSA-TOF facilitates screening for hundreds of compounds in minutes with minimal sample preparation, generating a comprehensive profile for each sample.

Introduction The role of herbal medicine in the treatment of common psychiatric disorders such as anxiety, depression and insomnia has become more established over the past decade. Some herbal preparations such as St John’s wort (Hypericum perforatum) have demonstrated clinical evidence but have also been included in recent reports of widespread adulteration and contamination. Herbal medicines sold in Australia are required to be listed on the Therapeutic Goods Administration’s (TGA) Australian Register of Therapeutic Goods (ARTG) and must comply with strict ingredient and manufacturing guidelines to assure quality and safety. Objective The aim of this research was to assess whether pharmaceutical adulterants and contaminants were present in psychotropic herbal medicines available in Australia, as a measure of quality, and the effectiveness of regulation. Methods A two-pronged approach combining next-generation DNA sequencing and small-molecule analysis techniques was undertaken to audit a subset of herbal medicines for the presence of prescription medications, illicit drugs, pesticides, herbicides, heavy metals and contaminant DNA. Small-molecule analysis included liquid chromatography with quadrupole time-of-flight mass spectrometer (LC-QTOF-MS) detection, liquid chromatography with UV/vis diode array (LC-UV) detection, gas chromatography with nitrogen–phosphorus and mass spectrometer detection (GC-NPD/MS) and heavy metal analysis using inductively coupled plasma with mass spectrometer (ICP-MS) detection. Results In total, 49% (29 of 59) of the investigated herbal medicines had one or more materials not listed on their labels or ARTG registration, including Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)-listed material (one medicine), heavy metals (12%) or components that could trigger food sensitivity, such as wheat (12%). In contrast to previous studies, no prescription pharmaceutical adulterants were detected, although 1

Introduction: The role of herbal medicine in the treatment of common psychiatric disorders such as anxiety, depression and insomnia has become more established over the past decade. Some herbal preparations such as St John’s wort (Hypericum perforatum) have demonstrated clinical evidence but have also been included in recent reports of widespread adulteration and contamination. Herbal medicines sold in Australia are required to be listed on the Therapeutic Goods Administration’s (TGA) Australian Register of Therapeutic Goods (ARTG) and must comply with strict ingredient and manufacturing guidelines to assure quality and safety. Objective: The aim of this research was to assess whether pharmaceutical adulterants and contaminants were present in psychotropic herbal medicines available in Australia, as a measure of quality, and the effectiveness of regulation. Methods: A two-pronged approach combining next-generation DNA sequencing and small-molecule analysis techniques was undertaken to audit a subset of herbal medicines for the presence of prescription medications, illicit drugs, pesticides, herbicides, heavy metals and contaminant DNA. Small-molecule analysis included liquid chromatography with quadrupole time-of-flight mass spectrometer (LC-QTOF-MS) detection, liquid chromatography with UV/vis diode array (LC-UV) detection, gas chromatography with nitrogen–phosphorus and mass spectrometer detection (GC-NPD/MS) and heavy metal analysis using inductively coupled plasma with mass spectrometer (ICP-MS) detection. Results: In total, 49% (29 of 59) of the investigated herbal medicines had one or more materials not listed on their labels or ARTG registration, including Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES)-listed material (one medicine), heavy metals (12%) or components that could trigger food sensitivity, such as wheat (12%). In contrast to previous studies, no prescription pharmaceutical adulterants were detected, althou

Herbal medicines are growing in popularity, use and commercial value; however, there remain problems with the quality and consequently safety of these products. Adulterated, contaminated and fraudulent products are often found on the market, a risk compounded by the fact that these products are available to consumers with little or no medical advice. Current regulations and quality control methods are lacking in their ability to combat these serious problems. Metabolomics is a biochemical profiling tool that may help address these issues if applied to quality control of both raw ingredients and final products. Using the example of the popular herbal medicine, ginseng, this essay offers an overview of the potential use of metabolomics for quality control in herbal medicines and also highlights where more research is needed.

Globally, there has been an increase in the use of herbal remedies including traditional Chinese medicine (TCM). There is a perception that products are natural, safe and effectively regulated, however, regulatory agencies are hampered by a lack of a toolkit to audit ingredient lists, adulterants and constituent active compounds. Here, for the first time, a multidisciplinary approach to assessing the molecular content of 26 TCMs is described. Next generation DNA sequencing is combined with toxicological and heavy metal screening by separation techniques and mass spectrometry (MS) to provide a comprehensive audit. Genetic analysis revealed that 50% of samples contained DNA of undeclared plant or animal taxa, including an endangered species of Panthera (snow leopard). In 50% of the TCMs, an undeclared pharmaceutical agent was detected including warfarin, dexamethasone, diclofenac, cyproheptadine and paracetamol. Mass spectrometry revealed heavy metals including arsenic, lead and cadmium, one with a level of arsenic >10 times the acceptable limit. The study showed 92% of the TCMs examined were found to have some form of contamination and/or substitution. This study demonstrates that a combination of molecular methodologies can provide an effective means by which to audit complementary and alternative medicines.

Globally, there has been an increase in the use of herbal remedies including traditional Chinese medicine (TCM). There is a perception that products are natural, safe and effectively regulated, however, regulatory agencies are hampered by a lack of a toolkit to audit ingredient lists, adulterants and constituent active compounds. Here, for the first time, a multidisciplinary approach to assessing the molecular content of 26 TCMs is described. Next generation DNA sequencing is combined with toxicological and heavy metal screening by separation techniques and mass spectrometry (MS) to provide a comprehensive audit. Genetic analysis revealed that 50% of samples contained DNA of undeclared plant or animal taxa, including an endangered species of Panthera (snow leopard). In 50% of the TCMs, an undeclared pharmaceutical agent was detected including warfarin, dexamethasone, diclofenac, cyproheptadine and paracetamol. Mass spectrometry revealed heavy metals including arsenic, lead and cadmium, one with a level of arsenic >10 times the acceptable limit. The study showed 92% of the TCMs examined were found to have some form of contamination and/or substitution. This study demonstrates that a combination of molecular methodologies can provide an effective means by which to audit complementary and alternative medicines.