Antioxidant, Antidiabetic, and Antihypertensive Properties of Echinacea purpurea Flower Extract and Caffeic Acid Derivatives Using In Vitro Models

Phenolic Profile, Bioactivities and In Silico Analysis of the Trunk Bark of Acacia Cyanophylla Lindl

In the current investigation, total phenolics and flavonoids of the methanolic extract obtained from the trunk bark of Acacia cyanophylla Lindl. were quantified by LC-HRMS technique. DPPH and ABTS reagents were employed to assay the antioxidant potential. The anti-tyrosinase and anti-α-amylase potentials were also assayed. The findings revealed that thirteen polyphenolic compounds were detected in the methanolic extract with trans-taxifolin (23.2 g/kg), as the major constituent. A. cyanophylla extract displayed a higher activity with DPPH test (IC50=10.14±1.00 μg/mL) than with ABTS (IC50=15.27±2.09 μg/mL). The same extract also exhibited interesting α-amylase inhibitory action (IC50 value of 4.00±0.17 μg/mL). Moreover, methanolic trunk bark extract exerted strong anti-tyrosinase capacity with an IC50 of 5.12±0.41 μg/mL in comparison to kojic acid (IC50=10.22±0.85 μg/mL) used as positive control. The antioxidant, anti-tyrosinase and anti-α-amylase potentials of the methanolic extract of A. cyanophylla trunk bark were reinforced by in silico molecular docking analyses, which confirmed the results of the in vitro tests.

Chemical Characterization of Phoenix dactylifera L. Seeds and their Beneficial Effects on the Vascular Response in Hypertensive Rats

Although Phoenix dactylifera dates are traditionally consumed for their health benefits, no research has been done on the vascular response in hypertensive animals. This study evaluated the vascular relaxation of hydroalcoholic extracts from seeds of three varieties of P. dactylifera; Sukkari seed (SS), Ajwa seed (AS), and Mabroom seed (MS) on L-NAME-induced hypertension and spontaneously hypertensive rats (SHR). Results showed that all extracts (10 µg/mL) caused relaxations higher than 60% in the aortic rings precontracted with 10- 6 M phenylephrine in normotensive rats, the SS extract was the most potent. Endothelial nitric oxide (NO) pathway is involved as significantly reduced vascular relaxation in denuded-endothelium rat aorta and with an inhibitor (10- 4 M L-Nω-Nitro arginine methyl ester; L-NAME) of endothelial nitric oxide synthase (eNOS). Confocal microscopy confirmed that 10 µg/mL SS extract increases NO generation as detected by DAF-FM fluorescence in intact aortic rings. Consistent with these findings, vascular relaxation in intact aortic rings at 10 µg/mL SS extract was significantly decreased in L-NAME-induced hypertensive rats (endothelial dysfunction model), but not in SHR. In both hypertensive models, the denuded endothelium blunted the vascular relaxation. In conclusion, the hydroalcoholic extract of the seed of P. dactylifera (Sukkari, Ajwa and Mabroom varieties) presents a potent endothelium-dependent vascular relaxation, via NO, in normotensive rats as well as in two different models of hypertension. This effect could be mediated by the presence of phenolic compounds identified by UHPLC-ESI-MS/MS, such as protocatechuic acid, and caftaric acid.

The consequences of fermentation metabolism on the qualitative qualities and biological activity of fermented fruit and vegetable juices

Fermentation of fruit and vegetable juices with probiotics is a novel nutritional approach with potential health benefits. Lactic acid fermentation-based biotransformation results in changes in the profile and nature of bioactive compounds and improves the organoleptic properties, shelf life and bioavailability of vitamins and minerals in the fermented juices. This process has been shown to enrich the phenolic profile and bioactivity components of the juices, resulting in a new type of functional food with improved health benefits. Fruits and vegetables are the ideal substrate for microbial growth, and fruit and vegetable juice will produce rich nutrients and a variety of functional activities after fermentation, so that the high-quality utilization of fruits and vegetables is realized, and the future fermented fruit and vegetable juice products have a wide application market. This paper explores the typical fermentation methods for fruit and vegetable juices, investigates the bioactive components, functional activities, and the influence of fermentation on enhancing the quality of fruit and vegetable juices. The insights derived from this study carry significant implications for guiding the development of fermented fruit and vegetable juice industry.

A multichannel closed bipolar platform to visual electrochemiluminescence sensing of caffeic acid as a model: Potential for multiplex detection

In this study, a fully-featured electrochemiluminescence (ECL) sensing platform based on a multichannel closed bipolar system (closed-BP, C-BP) for the determination of caffeic acid (CA) was successfully developed. The system comprises three individual reservoirs connected to each other by two pairs of gold rods as bipolar electrodes. Moreover, a single pair of gold rods functions as the driving electrodes. Due to configuration consisting of three channels and double-bipolar electrodes, the detection of CA was accomplished in two oxidation and reduction pathways within a single device. Firstly, through close observation of the reactions occurring within the device and utilizing a universal pH indicator and bipolar electrodes, a precise mechanism for the current bipolar systems was initially proposed. Then, the concentration of CA was monitored in the reporting chamber through the following ECL intensities resulting from luminol oxidation and H2O2. The monitoring process was performed using both a photomultiplier tube (PMT) and a digital camera. In the process of analyte oxidation, the PMT and visual (camera)-based detection exhibited a linear response from 5 μmol L-1 to 700 μmol L-1 (limit of detection (LOD) 1.2 μmol L-1) and 50 μmol L-1 to 600 μmol L-1 (LOD 14.8 μmol L-1), respectively. In the analyte reduction pathway, the respective values were 30 μmol L-1 to 450 μmol L-1 (LOD 8.6 μmol L-1) and 55 μmol L-1 to 400 μmol L-1 (LOD 21.2 μmol L-1), for the PMT and visual-based detection, respectively. Our experiments have demonstrated the practical application of the sensor array for efficient and high-performance analysis. This innovative design holds significant potential for diverse fields and paves the way for the development of a user-friendly device.

Development of Promising Flower-like Ag/SrFeO3 Nanosheet Electrode Materials: An Efficient and Selective Electrocatalytic Detection of Caffeic Acid in Coffee and Green Tea

The development of highly efficient electrocatalytic sensors is necessary for detection in various paramedical and industrial applications. Motivated by this concept, we demonstrate flower-like Ag/SrFeO3 nanostructures prepared by a facile route to modify electrocatalyst material for the detection of caffeic acid (CA). The surface morphology, phase structure, particle size, and pore volume were investigated through different physicochemical analytical techniques. The cyclic voltammetry technique was employed to evaluate the electrochemical behavior of both glassy carbon and modified Ag/SrFeO3 electrodes toward CA. The study revealed that the modified electrode shows excellent electrocatalytic activity toward CA compared to the reported values, with a wide linear range of 1-15 nM, a detection limit of 23 nM, good stability, and excellent repeatability. The superior results are attributed to numerous factors such as rapid electron transfer ability, tunable texture, high surface area, and good conductivity. The created Ag/SrFeO3 nanostructure-based electrochemical biosensor is a potential candidate for real-time analytical performance to directly detect CA in commercially available coffee and green tea without any pre-treatment.

Determination of the Bioactive Compounds from Echinacea purpurea (L.) Moench Leaves Extracts in Correlation with the Antimicrobial Activity and the In Vitro Wound Healing Potential

This study aimed at the relationship between antioxidant capacity, antimicrobial activity, and in vitro evaluation of the wound healing effect of the extract obtained from Echinaceae purpureae folium (EPF). This study's objective was to assess the bioactive components (total phenol and flavonoid content) and antioxidant activity of EPF extracts using the DPPH test method. The antioxidant capacity and the quantities of the compounds with antioxidant capacity were evaluated by spectrophotometric methods. Antimicrobial activity has been investigated against various pathogenic microorganisms. The minimum inhibitory concentration was determined by the microdilution method. Additionally, our work used a scratch test to examine the in vitro wound healing effects of EPF extract on NHDF cells. Statistical analysis was used to quantify the rate of migration and proliferation of fibroblast cells within the wound. Microscope pictures of fibroblast cells exposed to various EPF extract dosages were processed to estimate the width of the wound, area of the wound, and cell density inside the wound. The study proved that there was a relationship between the antioxidant, antimicrobial, and wound healing ability of EPF extracts.

Extraction, characterization of polyphenols from certain medicinal plants and evaluation of their antioxidant, antitumor, antidiabetic, antimicrobial properties, and potential use in human nutrition

Introduction

Dietary medicinal plants are among the most sought-after topics in alternative medicine today due to their preventive and healing properties against many diseases.

Aim

This study aimed to extract and determine the polyphenols from indigenous plants extracts, i.e., Mentha longifolia, M. arvensis, Tinospora cordifolia, Cymbopogon citratus, Foeniculum vulgare, Cassia absus, Camellia sinensis, Trachyspermum ammi, C. sinensis and M. arvensis, then evaluate the antioxidant, cytotoxicity, and antimicrobial properties, besides enzyme inhibition of isolated polyphenols.

Methods

The antioxidant activity was evaluated by DPPH, Superoxide radical, Hydroxyl radical (OH.), and Nitric oxide (NO.) scavenging activity; the antidiabetic activity was evaluated by enzymatic methods, and anticancer activity using MTT assay, while the antibacterial activity.

Results

The results showed that tested medicinal plants' polyphenolic extracts (MPPE) exhibited the most significant antioxidant activity in DPPH, hydroxyl, nitric oxide, and superoxide radical scavenging methods because of the considerable amounts of total polyphenol and flavonoid contents. UHPLC profile showed twenty-five polyphenol complexes in eight medicinal plant extracts, categorized into phenolic acids, flavonoids, and alkaloids. The main polyphenol was 3-Feroylquinic acid (1,302 mg/L), also found in M. longifolia, C. absus, and C. sinensis, has a higher phenolic content, i.e., rosmarinic acid, vanillic acid, chlorogenic acid, p-coumaric acid, ferulic acid, gallic acid, catechin, luteolin, 7-O-neohesperideside, quercetin 3,7-O-glucoside, hesperidin, rutin, quercetin, and caffeine in the range of (560-780 mg/L). At the same time, other compounds are of medium content (99-312 mg/L). The phenolics in C. sinensis were 20-116% more abundant than those in M. longifolia, C. absus, and other medicinal plants. While T. cordifolia is rich in alkaloids, T. ammi has a lower content. The MTT assay against Caco-2 cells showed that polyphenolic extracts of T. ammi and C. citratus had maximum cytotoxicity. While M. arvensis, C. sinensis, and F. vulgare extracts showed significant enzyme inhibition activity, C. sinensis showed minor inhibition activity against α-amylase. Furthermore, F. vulgare and C. sinensis polyphenolic extracts showed considerable antibacterial activity against S. aureus, B. cereus, E. coli, and S. enterica.

Discussion

The principal component analysis demonstrated clear separation among medicinal plants' extracts based on their functional properties. These findings prove the therapeutic effectiveness of indigenous plants and highlight their importance as natural reserves of phytogenic compounds with untapped potential that needs to be discovered through advanced analytical methods.

Physicochemical, Antioxidant, Sensory, and Starch Digestibility Properties of Steamed Bread Fortified with Tamarillo Powder

The effects of lyophilized tamarillo powder (TP) on the physicochemical, antioxidant, sensory, and starch digestibility characteristics of steamed breads were studied. The TP was used to substitute 5-20% of wheat flour to make steamed breads, assigned as T5, T10, T15, and T20, respectively. The results showed that TP is rich in dietary fiber (36.45%). Its extract is rich in bioactive components, including phenolic compounds (28.90 mg GAE/g extract), ascorbic acid (3.25 mg/g extract), total anthocyanins (316.35 μg C3GE/g extract), and total carotenoids (12.68 μg βCE/g extract) and has good antioxidant capacity. As the level of TP increased, the color of steamed breads became darker, redder, and yellower; the texture became harder, and the overall consumption preference decreased. However, their bioactive components content and antioxidant activity increased. The starch hydrolysis percentage of T5 (43.82%), T10 (41.57%), T15 (37.41%), and T20 (35.63%) at 180 min was significantly lower than that of the control (49.80%) (p < 0.05). The in vitro predicted glycemic index (80.02) of T20 was categorized as a medium-GI food when bread was used as the reference. On a nine-point hedonic test, control and T5 had the highest overall preference scores (7.1-7.4). The T20 supplemented with extra 15-20% water improved its volume and specific volume, and the overall preference scores (7.4-7.5) were not significantly different from the control (p > 0.05). Overall, a partial replacement of wheat flour with TP in steamed bread making could be developed as a new type of medium-GI value food containing more bioactive components and effective antioxidant capacity.

In Vivo Acute Toxicity and Immunomodulation Assessment of a Novel Nutraceutical in Mice

Achieving and maintaining a well-balanced immune system has righteously become an insightful task for the general population and an even more fundamental goal for those affected by immune-related diseases. Since our immune functions are indispensable in defending the body against pathogens, diseases and other external attacks, while playing a vital role in maintaining health and modulating the immune response, we require an on-point grasp of their shortcoming as a foundation for the development of functional foods and novel nutraceuticals. Seeing that immunoceuticals are considered effective in improving immune functions and reducing the incidence of immunological disorders, the main focus of this study was to assess the immunomodulatory properties and possible acute toxicity of a novel nutraceutical with active substances of natural origin on C57BL/6 mice for 21 days. We evaluated the potential hazards (microbial contamination and heavy metals) of the novel nutraceutical and addressed the acute toxicity according to OECD guidelines of a 2000 mg/kg dose on mice for 21 days. The immunomodulatory effect was assessed at three concentrations (50 mg/kg, 100 mg/kg and 200 mg/kg) by determining body and organ indexes through a leukocyte analysis; flow cytometry immunophenotyping of lymphocytes populations and their subpopulations (T lymphocytes (LyCD3+), cytotoxic suppressor T lymphocytes (CD3+CD8+), helper T lymphocytes (CD3+CD4+), B lymphocytes (CD3-CD19+) and NK cells (CD3-NK1.1.+); and the expression of the CD69 activation marker. The results obtained for the novel nutraceutical referred to as ImunoBoost indicated no acute toxicity, an increased number of lymphocytes and the stimulation of lymphocyte activation and proliferation, demonstrating its immunomodulatory effect. The safe human consumption dose was established at 30 mg/day.

Evaluation of anti-Alzheimer activity of Echinacea purpurea extracts in aluminum chloride-induced neurotoxicity in rat model

Alzheimer's disease (AD) is one of the neurodegenerative illnesses that impair individual life & increase the demand for caregivers with no available curative medication right now. Therefore, there is a growing concern about employing herbal medicine to limit AD progression & improve patients' life quality, thus potentiating its add-on therapy. In addition, herbs are cost-effective & accessible with nearly no side effects. In the same vein, our study aimed to investigate the potency of Echinacea purpurea (EP) flower extracts to ameliorate the neurodegenerative effect of Aluminum chloride (AlCl3) in a rat model. Moreover, mechanistic studies, including impact on the cholinesterase activity, redox status, inflammatory mediators, behavior performance, glucose level & histopathology, were carried on. Our results showed that 250 mg/kg of Aqueous (AQ) & Alcoholic (AL) extracts of EP inhibited cholinesterase, restored oxidative balance, down-regulated IL-6 & TNF-α cytokines & improved behavior performance in vivo that was reflected in the brain picture by decreasing neuronal degeneration & amyloid plaques in cerebral cortex & hippocampus. The potency of both extracts was compared to reference drugs & AlCl3 positive control group. The AQ extract showed greater potency against COX-1, COX-2 & α-amylase in vitro, while the AL extract was more potent against cholinesterase in vitro, inflammatory cytokines, behavior & pathological improvement in vivo. Conclusively EP overcame AlCl3-induced neurobehavioral toxicity in the rat model via different pathways, which support its regular administration to postpone progressive neural damage in AD patients.

Bioactive Compounds of Underground Valerian Extracts and Their Effect on Inhibiting Metabolic Syndrome-Related Enzymes Activities

Extractions of the underground parts of valerian were prepared with water and ethanol (25-95%) at 25-75 °C. Extraction yields, bioactive compounds, and the 1,1-Diphenyl-2-picrylhydrazyl (DPPH) radical scavenging ability of lyophilized extracts were determined. The inhibitory effects of the extracts, valerenic acid derivatives and phenolic acids, on metabolic syndrome (MS)-related enzymes activities were further examined. Both roots and rhizomes extracted with 95% ethanol at 75 °C had the highest levels of bioactive compounds. The antioxidant capacity and inhibition of MS-related enzymes of the roots extract were better than those of the rhizomes. The roots extract more strongly inhibited pancreatic lipase (inhibition of 50% of enzyme activity (IC₅₀), 17.59 mg/mL), angiotensin-converting enzyme (ACE, IC₅₀, 3.75 mg/mL), α-amylase (IC₅₀, 12.53 mg/mL), and α-glucosidase (IC₅₀, 15.40 mg/mL). These four phenolic acids inhibited the activity of MS-related enzymes. Valerenic acid demonstrated more of an inhibitory ability for ACE (IC₅₀, 0.225 mg/mL, except for caffeic acid) and α-glucosidase (IC₅₀, 0.617 mg/mL) than phenolic acids. Valerian extract inhibited key enzyme activities that were associated with obesity (lipase), hypertension (ACE), and type 2 diabetes (α-amylase and α-glucosidase), suggesting that it is a potential candidate for the development of functional supplements.

Ameliorative Effect of Ethanolic Echinacea purpurea against Hyperthyroidism-Induced Oxidative Stress via AMRK and PPAR Signal Pathway Using Transcriptomics and Network Pharmacology Analysis

Echinacea purpurea (L.) Moench (EP) is a well-known botanical supplement with antioxidant characteristics. However, the effects of EP on oxidative stress induced by hyperthyroidism have not yet been studied. This study was designed to evaluate the antioxidative effect of ethanolic Echinacea Purpurea (EEP) on hyperthyroidism-induced oxidative stress mice using an integrated strategy combining transcriptomics with network pharmacology analysis. Firstly, a hyperthyroidism mice model was induced via thyroxine (160 mg/kg) and EEP (1, 2, or 4 g/kg) once daily for 2 weeks. Body weight, thyroid-stimulating hormones, and oxidative stress markers were tested. Secondly, EEP regulating the potential genes at transcript level were analyzed. Thirdly, a network pharmacology based on the constituents of EEP identified using UPLC-Q-TOF-MS analysis was adopted. Finally, a joint analysis was performed to identify the key pathway. The results showed that EEP significantly changed the thyroid-stimulating hormones and oxidative stress markers. Meanwhile, RT-qPCR and Western Blotting demonstrated that the mechanism of the antioxidant effect of EEP reversed the mRNA expression of EHHADH, HMGCR and SLC27A2 and the protein expression of FABP and HMGCR in AMPK and PPAR signaling pathways. This study integrates transcriptomics with network pharmacology to reveal the mechanism of ameliorative effect of EEP on hyperthyroidism-induced oxidative stress.

The Pros and Cons of Using Elderberry (Sambucus nigra) for Prevention and Treatment of COVID-19

BACKGROUND

The novel severe acute respiratory syndrome coronavirus 2 emerged in 2019. Health-care systems around the world are looking for alternative prevention and treatment remedies. Herbal supplements are popular among consumers as a complementary method to prevent and treat illnesses. One of them is Sambucus nigra.

METHODS

We searched for related articles in Scopus, Web of Science, PubMed, Google Scholar, and the Directory of Open Access Journals using the following keywords: elderberry, S. nigra, and COVID-19.

RESULTS

Elderberry has antiviral properties due to its ability to modulate inflammatory cytokines. The current evidence suggests elderberry is appropriate for the prevention and initial treatment of viral disease. Concerns have been raised that elderberry may overstimulate the immune system, increasing the risk of a cytokine storm. There is not yet enough evidence to support this claim.

CONCLUSIONS

For COVID-19 patients, further research is required since elderberry may provoke a cytokine storm if administered therapeutically.

Phytovid19: a compilation of phytochemicals research in coronavirus

The COVID-19 pandemic has immensely impacted global health causing colossal damage. The recent outbreak of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) has increased the quest to explore phytochemicals as treatment options. We summarize phytochemicals with activity against various coronaviruses including SARS-CoV and Middle East respiratory syndrome coronavirus (MERS-CoV). We compiled 705 phytochemical compounds through text mining of 893 PubMed articles. The physicochemical properties including molecular weight, lipophilicity, and the number of hydrogen bond donors and acceptors were determined from the structures of these compounds. A structure-based evaluation of these properties with respect to drug likeness showed that most compounds have a positive score of drug likeness. QSAR analysis showed that 5 descriptors, namely polar surface area, relative polar surface area, number of hydrogen bond donors, solubility, and lipophilicity, are significantly related to IC50. We envisage that these phytochemicals could be further explored for developing new potential therapeutic molecules for COVID-19.

Eco-friendly synthesis of sulphur-doped graphenes with applicability in caffeic acid electrochemical assay

A new electrode based on glassy carbon modified with a sulphur-doped graphene material was successfully developed and applied for caffeic acid (CA) voltammetric detection and quantification. The structural features of sulphur-doped graphene (exfGR-S) characterized by different physicochemical and analytical techniques are presented. Cyclic voltammetry (CV) technique was employed to evaluate the electrochemical behavior of both bare glassy carbon (GCE) and modified GCE/exfGr-S electrodes towards CA oxidation. The study revealed that the modified electrode exhibits superior electrochemical performances compared to the bare electrode, with a broad CA detecting range (from 0.1 to 100.0 µM), a low detection limit 3.03 × 10^-8 M), excellent anti-interference capabilities, as well as good stability and repeatability. The developed electrochemical sensor appears to be a promising candidate for real sample quality control analysis since it successfully displayed its ability to directly detect CA in commercially available coffee product without any pretreatment.

Caffeic Acid, an Active Ingredient in Coffee, Combines with DOX for Multitarget Combination Therapy of Lung Cancer

Adjuvant diet therapy is an important means of comprehensive treatment of cancer. It is recognized by patients for its high safety, painlessness, and ease to operate. However, the development of adjuvant dietary therapy is limited by unclear targets and unclear anticancer mechanisms. In this work, caffeic acid was found as an inhibitor of TMEM16A with an IC₅₀ of 29.47 ± 3.19 μM by fluorescence quenching and whole-cell patch-clamp experiments. Caffeic acid regulated the proliferation, migration, and apoptosis of lung cancer cells targeting TMEM16A, which was detected by CCK-8, colony formation, wound healing, and Annexin V assays. In addition, molecular docking combined with site-directed mutagenesis confirmed that the binding sites of caffeic acid to TMEM16A were D439, E448, and R753. Western blot results indicated that caffeic acid regulated the growth of lung cancer through the MAPK pathway. In vitro experiments showed that the inhibitory effect of caffeic acid combined with hydroxydaunorubicin (DOX) on lung cancer cell growth was better than a double concentration of any single dose. In vivo pharmacokinetic experiments and tumor xenograft experiments indicated that the combination of 5.4 mg/kg caffeic acid and 4.1 mg/kg DOX achieved 85.6% tumor suppression rate and offset the side effects. Therefore, caffeic acid is a safe and efficient antitumor active ingredient of food that can enhance the antitumor effect of DOX.

Plant-Derived Natural Products as Lead Agents against Common Respiratory Diseases

Never has the world been more challenged by respiratory diseases (RDs) than it has witnessed in the last few decades. This is evident in the plethora of acute and chronic respiratory conditions, ranging from asthma and chronic obstructive pulmonary disease (COPD) to multidrug-resistant tuberculosis, pneumonia, influenza, and more recently, the novel coronavirus (COVID-19) disease. Unfortunately, the emergence of drug-resistant strains of pathogens, drug toxicity and side effects are drawbacks to effective chemotherapeutic management of RDs; hence, our focus on natural sources because of their unique chemical diversities and novel therapeutic applications. This review provides a summary on some common RDs, their management strategies, and the prospect of plant-derived natural products in the search for new drugs against common respiratory diseases.

Echinacea purpurea (L.) Moench: Biological and Pharmacological Properties. A Review

Echinacea purpurea (L.) Moench (EP)is a perennial herbaceous flowering plant, commonly known as purple coneflower and it belongs to the Asteraceae family. The Echinacea genus is originally from North America, in the United States, and its species are widely distributed throughout. There are nine different species of Echinacea, but only three of them are used as medicinal plants with wide therapeutic uses: Echinacea purpurea (L.) Moench, Echinacea pallida (Nutt.) Nutt. and Echinacea angustifolia DC. Several significant groups of bioactive compounds with pharmacological activities have been isolated from Echinacea species. Numerous beneficial effects have been demonstrated about these compounds. The immunomodulatory effect was initially demonstrated, but over time other effects have also been highlighted. The present review gives a comprehensive summary of the chemical constituents, bioactive compounds, biological effects and therapeutical uses of purple coneflower. Research shows that such a well-known and recognized species needs to be further studied to obtain efficient products with a guarantee of the safety.

Potential Therapeutic Implications of Caffeic Acid in Cancer Signaling: Past, Present, and Future

Caffeic acid (CA) has been present in many herbs, vegetables, and fruits. CA is a bioactive compound and exhibits various health advantages that are linked with its anti-oxidant functions and implicated in the therapy and prevention of disease progression of inflammatory diseases and cancer. The anti-tumor action of CA is attributed to its pro-oxidant and anti-oxidant properties. CA’s mechanism of action involves preventing reactive oxygen species formation, diminishing the angiogenesis of cancer cells, enhancing the tumor cells’ DNA oxidation, and repressing MMP-2 and MMP-9. CA and its derivatives have been reported to exhibit anti-carcinogenic properties against many cancer types. CA has indicated low intestinal absorption, low oral bioavailability in rats, and pitiable permeability across Caco-2 cells. In the present review, we have illustrated CA’s therapeutic potential, pharmacokinetics, and characteristics. The pharmacological effects of CA, the emphasis on in vitro and in vivo studies, and the existing challenges and prospects of CA for cancer treatment and prevention are discussed in this review.

Protective effect of ethanolic extract of Echinacea purpurea contained nanoparticles on meniscal/ligamentous injury induced osteoarthritis in obese male rats

Osteoarthritis (OA) is a chronic degenerative joint disease associated with age, mechanical stress, and obesity. Echinacea purpurea is a medicinal plant that shows good anti-inflammatory, antioxidant, and immunomodulatory activities. In this study, Echinacea purpurea ethanol extract nanoparticles (Nano-EE) were prepared by encapsulating Echinacea purpurea ethanol extract (EE) in chitosan-silica nanoparticles. Obesity (OB) in Sprague-Dawley (SD) rats was induced by fed 40% high-fat diet and then anterior cruciate ligament and meniscus injury were performed to induce OA. The rats got different doses of samples by oral gavage. The encapsulation efficiency and loading capacity of Nano-EE were 69.1% and 36.1%, respectively. The average size, polydispersity index (PDI), and zeta potential (ZP) of the Nano-EE were 145 ± 11 nm, 0.24 ± 0.01, − 4.57 ± 0.44 mV, respectively. Furthermore, electron microscopic images showed that the particles were spherical and were slightly agglomerated. Moreover, it showed that the leptin content, expression of MMPs, cytokines level, NF-κB level, and iNOS production were decreased whereas collagen II expression was increased after treatment. Besides, Nano-EE ameliorated the pain caused by OA and reduced the proteoglycan loss in cartilage. These results indicated that encapsulated EE (Nano-EE) can ameliorate OA with a low dosage and are more effective than unencapsulated EE.

Potential Therapeutic Implications of Caffeic Acid in Cancer Signaling: Past, Present, and Future

Caffeic acid (CA) has been present in many herbs, vegetables, and fruits. CA is a bioactive compound and exhibits various health advantages that are linked with its anti-oxidant functions and implicated in the therapy and prevention of disease progression of inflammatory diseases and cancer. The anti-tumor action of CA is attributed to its pro-oxidant and anti-oxidant properties. CA’s mechanism of action involves preventing reactive oxygen species formation, diminishing the angiogenesis of cancer cells, enhancing the tumor cells’ DNA oxidation, and repressing MMP-2 and MMP-9. CA and its derivatives have been reported to exhibit anti-carcinogenic properties against many cancer types. CA has indicated low intestinal absorption, low oral bioavailability in rats, and pitiable permeability across Caco-2 cells. In the present review, we have illustrated CA’s therapeutic potential, pharmacokinetics, and characteristics. The pharmacological effects of CA, the emphasis onin vitro and in vivostudies, and the existing challenges and prospects of CA for cancer treatment and prevention are discussed in this review.

Root Cultures, a Boon for the Production of Valuable Compounds: A Comparative Review

Medicinal plants are an inevitable source of pharmaceutical drugs and most of the world population depends on these plants for health benefits. The increasing global demand for bioactive compounds from medicinal plants has posed a great threat to their existence due to overexploitation. Adventitious root and hairy root culture systems are an alternative approach to the conventional method for mass production of valuable compounds from medicinal plants owing to their rapid growth, biosynthetic and genetic stability. The main purpose of this review is to investigate the recent scientific research published worldwide on the application of adventitious and hairy root cultures to produce valuable compounds from medicinal plants. Furthermore, a comparison of adventitious root vs. hairy root cultures to produce valuable compounds has also been discussed. Various aspects such as medium composition, carbon source, pH, amount of macronutrients, optimization strategy, scale-up cultures, and use of biotic abiotic and nano-elicitors at various concentrations are the topic of discussion in this review. Several studies on adventitious and hairy root cultures of Polygonum multiflorum&cedil; Withania somnifera&cedil; Echinacea purpurea and Ajuga bracteosa have been discussed in detail which highlights the importance of elicitation strategies and bioreactor system, presenting commercial applications.

The effects of ultrasonication on the phytochemicals, antioxidant, and polyphenol oxidase and peroxidase activities in coffee leaves

In the present study, we investigated the impacts of ultrasonic conditions on the phytochemical profiles, antioxidant activity, and polyphenol oxidase (PPO) and peroxidase (POD) activities in coffee leaves. Ultrasonic frequency, power, and time, pH, and incubation time affected PPO and POD differently, thus resulting in different ABTS scavenging capacity and phenolic content in coffee leaves. Triple-frequency (20/35/50 kHz) ultrasound significantly (P < 0.05) inhibited trigonelline, caffeine, mangiferin, rutin, chlorogenic acids, antioxidant activity, and PPO activity, while the single frequency of 35 kHz increased the phenolics compounds, which was associated with the lowest POD activity. Increasing the incubation time after ultrasonication gradually decreased phenolic compounds and antioxidant activities, however, POD activity followed a temporal pattern of first increase and then decrease. Our results showed that PPO and POD were temporally inactivated after ultrasonication, which leading to the continuous decrease of phenolics in coffee leaves.

Quantification of Major Bioactive Constituents, Antioxidant Activity, and Enzyme Inhibitory Effects of Whole Coffee Cherries (Coffea arabica) and Their Extracts

Coffee cherry is a rich source of chlorogenic acids (CGAs) and caffeine. In this study we examined the potential antioxidant activity and enzyme inhibitory effects of whole coffee cherries (WCC) and their two extracts on α-amylase, α-glucosidase and acetylcholinesterase (AChE) activities, which are targets for the control of diabetes and Alzheimer’s diseases. Whole coffee cherry extract 40% (WCCE1) is rich in chlorogenic acid compounds, consisting of a minimum of 40% major isomers, namely 3-caffeoylquinic acids, 4-caffeoylquinic acids, 5-caffeoylquinic acids, 3,4-dicaffeoylquinic acid, 3,5-dicaffeoylquinic acid, 4,5-dicaffeoylquinic acid, 4-feruloylquinc acid, and 5-feruloylquinc acid. Whole coffee cherry extract 70% (WCCE2) is rich in caffeine, with a minimum of 70%. WCCE1 inhibited the activities of digestive enzymes α-amylase and α-glucosidase, and WCCE2 inhibited acetylcholinesterase activities with their IC₅₀ values of 1.74, 2.42, and 0.09 mg/mL, respectively. Multiple antioxidant assays—including DPPH, ABTS, FRAP, ORAC, HORAC, NORAC, and SORAC—demonstrated that WCCE1 has strong antioxidant activity.

Antioxidant and anticancer potentials of edible flowers: where do we stand?

Edible flowers are attracting special therapeutic attention and their administration is on the rise. Edible flowers play pivotal modulatory roles on oxidative stress and related interconnected apoptotic/inflammatory pathways toward the treatment of cancer. In this review, we highlighted the phytochemical content and therapeutic applications of edible flowers, as well as their modulatory potential on the oxidative stress pathways and apoptotic/inflammatory mediators, resulting in anticancer effects. Edible flowers are promising sources of phytochemicals (e.g., phenolic compounds, carotenoids, terpenoids) with several therapeutic effects. They possess anti-inflammatory, anti-diabetic, anti-microbial, anti-depressant, anxiolytic, anti-obesity, cardioprotective, and neuroprotective effects. Edible flowers potentially modulate oxidative stress by targeting erythroid nuclear transcription factor-2/extracellular signal-regulated kinase/mitogen-activated protein kinase (Nrf2/ERK/MAPK), reactive oxygen species (ROS), nitric oxide (NO), malondialdehyde (MDA) and antioxidant response elements (AREs). As the interconnected pathways to oxidative stress, inflammatory mediators, including tumor necrosis factor (TNF)-α, nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB), interleukins (ILs) as well as apoptotic pathways such as Bcl-2-associated X protein (Bax), Bcl-2, caspase and cytochrome C are critical targets of edible flowers in combating cancer. In this regard, edible flowers could play promising anticancer effects by targeting oxidative stress and downstream dysregulated pathways.

Natural Agents Modulating ACE-2: A Review of Compounds with Potential against SARS-CoV-2 Infections

One of the biggest challenges of public health worldwide is reducing the number of events and deaths related to severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infections. The angiotensinconverting enzyme 2 (ACE-2), a carboxypeptidase that degrades angiotensin II into angiotensin 1-7, has been identified as a potent receptor for SARS-CoV-2. In the last decades, ACE inhibition has assumed a central role in reducing cardiovascular and renal events. However, with the advent of COVID-19, attention has been turned to ACE-2 as a possible target to reduce virus binding to different human cells. This review aims to discuss recent developments related to the medicinal properties of natural compounds as ACE/ACE-2 inhibitors, which should be highlighted in the future development of studies looking for modulators in SARS-CoV-2 infection. Data show that bioactive compounds isolated from several natural products act by inhibiting ACE/ACE-2, which changes the entire axis of this system. Of the compounds addressed in this review, 7 phenolic compounds, including quercetin, curcumin, naringenin, luteolin, hesperidin, mangiferin, and gallic acid showed binding affinity with molecular ACE-2 target in silico, and 1, esculetin, decreased ACE-2 expression in vivo. Regarding terpenoids and alkaloids, nimbin, withaferin A, andrographolide, zingiberene and, berberine, piperine and thebaine, respectively, showed a binding affinity with molecular ACE-2 target in silico. These findings reinforce the need for future preclinical and clinical studies on these compounds and specific inhibitory effects on ACE-2 of all the other compounds described herein only as nonspecific ACE inhibitors. It is important to mention that some natural compounds such as magnolol, resveratrol, rosmarinic acid, tanshinone IIA, and nicotine have also demonstrated the potential to increase the activity or expression of ACE-2, and could therefore aggravate SARS-CoV-2 infection.

Biochemometric Analysis of Fatty Acid Amide Hydrolase Inhibition by Echinacea Root Extracts

Recent research demonstrates that Echinacea possesses cannabimimetic activity with potential applications beyond common contemporary uses for relief of cold and flu symptoms. In this study, we investigated the in vitro inhibitory effect of root extracts of Echinacea purpurea and Echinacea angustifolia on fatty acid amide hydrolase, the main enzyme that degrades the endocannabinoid anandamide. The objective was to relate variation in bioactivity between commercial Echinacea genotypes to their phytochemical profiles and to identify determinants of activity using biochemometric analysis. Forty root extracts of each of species were tested for inhibition of fatty acid amide hydrolase and analyzed by HPLC-DAD/MS to identify and quantitate alkylamides and caffeic acid derivatives. Fatty acid amide hydrolase inhibition ranged from 34 - 80% among E. angustifolia genotypes and from 33 - 87% among E. purpurea genotypes. Simple linear regression revealed the caffeic acid derivatives caftaric acid and cichoric acid, and the alkylamide dodeca-2E,4Z-diene-8,10-diynioc acid 2-methylbutylamide, as the strongest determinants of inhibition in E. purpurea (r* = 0.53, 0.45, and 0.20, respectively) while in E. angustifolia, only CADs were significantly associated with activity, most notably echinacoside (r* = 0.26). Regression analysis using compound groups generated by hierarchical clustering similarly indicated that caffeic acid derivatives contributed more than alkylamides to in vitro activity. Testing pure compounds identified as determinants of activity revealed cichoric acid (IC₅₀ = 45 ± 4 µM) and dodeca-2E,4E,8Z,10E-tetraenoic acid isobutylamide (IC₅₀ = 54 ± 2 µM) as the most active. The results suggest that several phytochemicals may contribute to Echinacea's cannabimimetic activity and that ample variation in genotypes exists for selection of high-activity germplasm in breeding programs.

Can Echinacea be a potential candidate to target immunity, inflammation, and infection - The trinity of coronavirus disease 2019

Coronavirus disease 2019 (COVID-19) pandemic caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), is an ongoing public health emergency. The pathogenesis and complications advanced with infection mainly involve immune-inflammatory cascade. Therefore, the therapeutic strategy relies on immune modulation, reducing infectivity and inflammation. Given the interplay of infection and immune-inflammatory axis, the natural products received attention for preventive and therapeutic usage in COVID-19 due to their potent antiviral and anti-immunomodulatory activities. Recently, Echinacea preparations, particularly E. purpurea, have been suggested to be an important antiviral agent to be useful in COVID-19 by modulating virus entry, internalization and replication. In principle, the immune response and the resultant inflammatory process are important for the elimination of the infection, but may have a significant impact on SARS-CoV-2 pathogenesis and may play a role in the clinical spectrum of COVID-19. Considering the pharmacological effects, therapeutic potential, and molecular mechanisms of Echinacea, we hypothesize that it could be a reasonably possible candidate for targeting infection, immunity, and inflammation in COVID-19 with recent recognition of cannabinoid-2 (CB2) receptors and peroxisome proliferator-activated receptor gamma (PPARγ) mediated mechanisms of bioactive components that make them notable immunomodulatory, anti-inflammatory and antiviral agent. The plausible reason for our hypothesis is that the presence of numerous bioactive agents in different parts of plants that may synergistically exert polypharmacological actions in regulating immune-inflammatory axis in COVID-19. Our proposition is to scientifically contemplate the therapeutic perspective and prospect of Echinacea on infection, immunity, and inflammation with a potential in COVID-19 to limit the severity and progression of the disease. Based on the clinical usage for respiratory infections, and relative safety in humans, further studies for the evidence-based approach to COVID-19 are needed. We do hope that Echinacea could be a candidate agent for immunomodulation in the prevention and treatment of COVID-19.

A Review on Plant Bioactive Compounds and Their Modes of Action Against Coronavirus Infection

The rapid outbreak of coronavirus disease 2019 (COVID-19) has demonstrated the need for development of new vaccine candidates and therapeutic drugs to fight against the underlying virus, severe acute respiratory syndrome-coronavirus-2 (SARS-CoV-2). Currently, no antiviral treatment is available to treat COVID-19 as treatment is mostly directed to only relieving the symptoms. Retrospectively, herbal medicinal plants have been used for thousands of years as a medicinal alternative including for the treatment of various viral illnesses. However, a comprehensive description using various medicinal plants in treating coronavirus infection has not to date been described adequately, especially their modes of action. Most other reports and reviews have also only focused on selected ethnobotanical herbs such as Traditional Chinese Medicine, yet more plants can be considered to enrich the source of the anti-viral compounds. In this review, we have screened and identified potential herbal medicinal plants as anti-coronavirus medication across major literature databases without being limited to any regions or ethnobotanic criteria. As such we have successfully gathered experimentally validated in vivo, in vitro, or in silico findings of more than 30 plants in which these plant extracts or their related compounds, such as those of Artemisia annua L., Houttuynia cordata Thunb., and Sambucus formosana Nakai, are described through their respective modes of action against specific mechanisms or pathways during the viral infection. This includes inhibition of viral attachment and penetration, inhibition of viral RNA and protein synthesis, inhibition of viral key proteins such as 3-chymotrypsin-like cysteine protease (3CLpro) and papain-like protease 2 (PLpro), as well as other mechanisms including inhibition of the viral release and enhanced host immunity. We hope this compilation will help researchers and clinicians to identify the source of appropriate anti-viral drugs from plants in combating COVID-19 and, ultimately, save millions of affected human lives.

Exploring the protective effect of Gynura procumbens against type 2 diabetes mellitus by network pharmacology and validation in C57BL/KsJ db/db mice

Flowchart of the experimental procedures.

Anti-COVID-19 drug candidates: A review on potential biological activities of natural products in the management of new coronavirus infection

Background and aim

The novel coronavirus disease (COVID-19) caused by severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is now become a worldwide pandemic bringing over 71 million confirmed cases, while the specific drugs and vaccines approved for this disease are still limited regarding their effectiveness and adverse events. Since virus incidences are still on rise, infectivity and mortality may also rise in the near future, natural products are highly considered to be valuable sources for the discovery of new antiviral drugs against SARS-CoV-2. This present review aims to comprehensively summarize the up-to-date scientific literatures on biological activities of plant- and mushroom-derived compounds relevant to mechanistic targets involved in SARS-CoV-2 infection and inflammatory-associated pathogenesis, including viral entry, replication and release, and the renin-angiotensin-aldosterone system (RAAS).

Experimental procedure

Data were retrieved from a literature search available on PubMed, Scopus and Google Scholar databases and collected until the end of May 2020. The findings from in vitro cell and non-cell based studies were considered, while the results of in silico studies were excluded.

Results and conclusion

Based on the previous findings in SARS-CoV studies, except in silico molecular docking analysis, herein, we provide a total of 150 natural compounds as potential candidates for development of new anti-COVID-19 drugs with higher efficacy and lower toxicity than the existing therapeutic agents. Several natural compounds have showed their promising actions on multiple therapeutic targets, which should be further explored. Among them, quercetin, one of the most abundant of plant flavonoids, is proposed as a lead candidate with its ability on the virus side to inhibit SARS-CoV spike protein-angiotensin-converting enzyme 2 (ACE2) interaction, viral protease and helicase activities, as well as on the host cell side to inhibit ACE activity and increase intracellular zinc level.

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Relevant and up-to-date publications in natural products with anti-COVID-19 potential.

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Emphasis on the potential of anti-COVID-19 plant/mushroom-based medicine.

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Twenty four proposed natural compounds for the anti-COVID-19 drug candidates.

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Quercetin emerged as the most promising compound acting on multiple therapeutic targets.

Voltamperometric Sensors and Biosensors Based on Carbon Nanomaterials Used for Detecting Caffeic Acid-A Review

Caffeic acid is one of the most important hydroxycinnamic acids found in various foods and plant products. It has multiple beneficial effects in the human body such as antioxidant, antibacterial, anti-inflammatory, and antineoplastic. Since overdoses of caffeic acid may have negative effects, the quality and quantity of this acid in foods, pharmaceuticals, food supplements, etc., needs to be accurately determined. The present paper analyzes the most representative scientific papers published mostly in the last 10 years which describe the development and characterization of voltamperometric sensors or biosensors based on carbon nanomaterials and/or enzyme commonly used for detecting caffeic acid and a series of methods which may improve the performance characteristics of such sensors.

Water-Based Extraction of Bioactive Principles from Blackcurrant Leaves and Chrysanthellum americanum: A Comparative Study

The water-based extraction of bioactive components from flavonoid-rich medicinal plants is a key step that should be better investigated. This is especially true when dealing with easy-to-use home-made conditions of extractions, which are known to be a bottleneck in the course for a better control and optimization of the daily uptake of active components from medicinal plants. In this work, the water-based extraction of Blackcurrant (Ribes nigrum) leaves (BC) and Chrysanthellum americanum (CA), known to have complementary pharmacological properties, was studied and compared with a previous work performed on the extraction of Hawthorn (Crataegus, HAW). Various extraction modes in water (infusion, percolation, maceration, ultrasounds, microwaves) were compared for the extraction of bioactive principles contained in BC and CA in terms of extraction yield, of amount of flavonoids, phenolic compounds, and proanthocyanidin oligomers, and of UHPLC profiles of the extracted compounds. The qualitative and quantitative aspects of the extraction, in addition to the kinetic of extraction, were studied. The optimized easy-to-use-at-home extraction protocol developed for HAW was found very efficient to easily extract bioactive components from BC and CA plants. UHPLC-ESI-MS and high-resolution Fourier transform ion cyclotron resonance mass spectrometry (FT-ICR MS) were also implemented to get more qualitative information on the specific and common chemical compositions of the three plants (including HAW). Their antihyaluronidase, antioxidant, and antihypertensive activities were also determined and compared, demonstrating similar activities as the reference compound for some of these plants.

Comparative Study of Leaf and Rootstock Aqueous Extracts of Foeniculum vulgare on Chemical Profile and In Vitro Antioxidant and Antihyperglycemic Activities

Foeniculum vulgare is a medicinal plant used in Moroccan folk medicine to treat several diseases such as diabetes. The aim of this study was to determine the phenolic bioactive compounds and to evaluate the antioxidant and antihyperglycemic activities of Foeniculum vulgare leaf and rootstock extracts. Phenolic compounds of F. vulgare rootstock and leaf extracts were determined using HPLC-DAD-QTOFMS analysis. The antioxidant activity was evaluated using 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2,2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS•+) radicals. Moreover, the in vitro antihyperglycemic effects were tested by measuring the inhibition of α-amylase and α-glucosidase activities. HPLC-DAD-QTOFMS analysis identified thirty-two phenolic components in both leaf and rootstock extracts. Caffeic acid, quinic acid, and chlorogenic acid were the major compounds of F. vulgare leaf extract (FVLE), while the main compound of F. vulgare rootstock extracts (FVRE) was quinic acid. In the DPPH assay, F. vulgare leaf extract showed important antioxidant activity (IC50 = 12.16 ± 0.02 μg/mL) than F. vulgare rootstock extract (IC50 = 34.36 ± 0.09 μg/mL). Moreover, fennel leaf extracts revealed also the most powerful antioxidant activity (IC50 = 22.95 ± 0.4 μg/mL) in the ABTS assay. The in vitro antihyperglycemic activity showed that F. vulgare rootstock extract exhibited a remarkable inhibitory capacity (IC50 = 194.30 ± 4.8 μg/mL) of α-amylase compared with F. vulgare leaf extract (IC50 = 1026.50 ± 6.5 μg/mL). Furthermore, the inhibition of α-glucosidase was more importantly with F. vulgare rootstock (IC50 of 165.90 ± 1.2 μg/mL) than F. vulgare leaf extracts (203.80 ± 1.3 μg/mL). The funding of this study showed that F. vulgare rootstock and leaf extracts presented several phenolic compounds and showed important antioxidant and antidiabetic effects. We suggest that the identified molecules are responsible for the obtained activities. However, further studies focusing on the isolation and the determination of antioxidant and antidiabetic effects of F. vulgare rootstock and leaf main compounds are required.

An update on the health benefits promoted by edible flowers and involved mechanisms

The aim of this review is to provide new findings on health effects of edible flowers since 2015. The antioxidant, anti-inflammatory, anti-cancer, hepatoprotective, neuroprotective, anti-diabetic, anti-osteoporosis, anti-obesity, and anti-hypertensive have been reviewed, and the effective concentrations of flower extracts have been summarized. Among all the health benefits mentioned, anti-osteoporosis, anti-obesity, and anti-hypertensive have rarely been mentioned before 2015. Some health benefits mechanisms of edible flowers were discussed frequently after 2015. Some newly found phytochemicals such as polysaccharides were shown to be beneficial to human health. Species of Rosa, Chrysanthemum, and Osmanthus have been reported to exert different health effects on human. For the toxicity studies, the safe level of flower extracts in cell and animal models were at hundreds of parts per million (ppm) level. In consideration of health promoting effects and toxicities of edible flowers, they could serve as potential natural health products for different health benefits.

Natural Sources, Pharmacokinetics, Biological Activities and Health Benefits of Hydroxycinnamic Acids and Their Metabolites

Hydroxycinnamic acids (HCAs) are important natural phenolic compounds present in high concentrations in fruits, vegetables, cereals, coffee, tea and wine. Many health beneficial effects have been acknowledged in food products rich in HCAs; however, food processing, dietary intake, bioaccessibility and pharmacokinetics have a high impact on HCAs to reach the target tissue in order to exert their biological activities. In particular, metabolism is of high importance since HCAs' metabolites could either lose the activity or be even more potent compared to the parent compounds. In this review, natural sources and pharmacokinetic properties of HCAs and their esters are presented and discussed. The main focus is on their metabolism along with biological activities and health benefits. Special emphasis is given on specific effects of HCAs' metabolites in comparison with their parent compounds.

Inhibitory Activities of Polyphenolic Extracts of Bangladeshi Vegetables against α-Amylase, α-Glucosidase, Pancreatic Lipase, Renin, and Angiotensin-Converting Enzyme

The aim of the study was to determine the in vitro enzyme inhibition activities of aqueous polyphenolic extracts of nine popular Bangladeshi vegetables, namely ash gourd, bitter gourd, brinjal, Indian spinach, kangkong, okra, ridge gourd, snake gourd, and stem amaranth. Polyphenolic glycosides were the major compounds present in the extracts. Inhibition of α-amylase (up to 100% at 1 mg/mL) was stronger than α-glucosidase inhibition (up to 70.78% at 10 mg/mL). The Indian spinach extract was the strongest inhibitor of pancreatic lipase activity (IC₅₀ = 276.77 µg/mL), which was significantly better than that of orlistat (381.16 µg/mL), a drug. Ash gourd (76.51%), brinjal (72.48%), and snake gourd (66.82%) extracts were the most effective inhibitors of angiotensin-converting enzyme (ACE), an enzyme whose excessive activities have been associated with hypertension. Brinjal also had a significantly higher renin-inhibitory activity than the other vegetable extracts. We conclude that the vegetable extracts may have the ability to reduce enzyme activities that have been associated with hyperglycemia, hyperlipidemia, and hypertension.

Echinacea purpurea (L.) Moench: Chemical Characterization and Bioactivity of Its Extracts and Fractions

Echinacea purpurea (L.) Moench is widely known for its medicinal properties, being one of the most used medicinal plants for its immunostimulant properties. Nevertheless, there is still scarce information on its cytotoxic activity. Thus, this study aims at evaluating the cytotoxicity and antimicrobial activity of several aqueous and organic extracts of the aerial parts of this plant and chemically characterizing the obtained extracts. The analysis was performed by HPLC-DAD-ESI/MS. Fifteen compounds were identified; of these, seven were phenolic acids and eight were flavonoids. Non-polar compounds were evaluated by GC/MS, with a total of sixty-four compounds identified, and the most abundant groups were the sterols, fatty acids and long-chain hydrocarbons. The highest antimicrobial activity was exhibited by the dichloromethane, ethyl acetate, and acetone extracts. Dichloromethane and n-hexane extracts showed the highest cytotoxic activity. Therefore, they were fractionated, and the obtained fractions were also assessed for their cytotoxicity. Notwithstanding, the cytotoxicity of the extracts was superior to that of the obtained fractions, evidencing a possible synergistic effect of different compounds in the whole extracts.

Recent Advances in the Knowledge of Naturally-derived Bioactive Compounds as Modulating Agents of the Renin-angiotensin-aldosterone System: Therapeutic Benefits in Cardiovascular Diseases

BACKGROUND

One of the biggest challenges to public health worldwide is to reduce the number of events and deaths related to the cardiovascular diseases. Numerous approaches have been applied to reach this goal, and drug treatment intervention has been indispensable along with an effective strategy for reducing both cardiovascular morbidity and mortality. Renin-angiotensin-aldosterone system (RAAS) blockade is currently one of the most important targets of cardiovascular drug therapy. Many studies have proven the valuable properties of naturally-derived bioactive compounds to treat cardiovascular diseases.

METHODS

The goal of this review, therefore, is to discuss the recent developments related to medicinal properties about natural compounds as modulating agents of the RAAS, which have made them an attractive alternative to be available to supplement the current therapy options.

RESULTS

Data has shown that bioactive compounds isolated from several natural products act either by inhibiting the angiotensin-converting enzyme or directly by modulating the AT1 receptors of angiotensin II, which consequently changes the entire classical axis of this system.

CONCLUSION

While there are a few evidence about the positive actions of different classes of secondary metabolites for the treatment of cardiovascular and renal diseases, data is scarce about the clinical assays established to demonstrate their value in humans.

Antiviral activity of Sambucus FormosanaNakai ethanol extract and related phenolic acid constituents against human coronavirus NL63

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Sambucus FormosanaNakai extract reduced cytopathicity and virus yield in HCoV-NL63-infected cells.

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Among phenolic acid constituents, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity.

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Sambucus FormosanaNakai extract and caffeic acid concentration-dependently inhibited HCoV-NL63 attachment onto cells.

Human coronavirus NL63 (HCoV-NL63), one of the main circulating HCoVs worldwide, causes respiratory tract illnesses like runny nose, cough, bronchiolitis and pneumonia. Recently, a severe respiratory illness outbreak of HCoV-NL63 has been reported in a long-term care facility. Sambucus FormosanaNakai, a species of elderberry, is a traditional medicinal herb with anti-inflammatory and antiviral potential. The study investigated the antiviral activity of Sambucus FormosanaNakai stem ethanol extract and some phenolic acid constituents against HCoV-NL63. The extract was less cytotoxic and concentration-dependently increased anti-HCoV-NL63 activities, including cytopathicity, sub-G1 fraction, virus yield (IC50 = 1.17 μg/ml), plaque formation (IC50 = 4.67 μg/ml) and virus attachment (IC50 = 15.75 μg/ml). Among the phenolic acid constituents in Sambucus FormosanaNakai extract, caffeic acid, chlorogenic acid and gallic acid sustained the anti-HCoV-NL63 activity that was ranked in the following order of virus yield reduction: caffeic acid (IC₅₀ = 3.54 μM) > chlorogenic acid (IC₅₀ = 43.45 μM) > coumaric acid (IC₅₀ = 71.48 μM). Caffeic acid significantly inhibited the replication of HCoV-NL63 in a cell-type independent manner, and specifically blocked virus attachment (IC₅₀ = 8.1 μM). Therefore, the results revealed that Sambucus Formosana Nakai stem ethanol extract displayed the strong anti-HCoV-NL63 potential; caffeic acid could be the vital component with anti-HCoV-NL63 activity. The finding could be helpful for developing antivirals against HCoV-NL63.

Medicinal plants with concomitant anti-diabetic and anti-hypertensive effects as potential sources of dual acting therapies against diabetes and hypertension: A review

ETHNOPHARMACOLOGICAL RELEVANCE

Diabetes and hypertension are pathophysiologically related diseases that co-exist with a wider complex of metabolic diseases having similar set of risk factors. There are numerous ethnopharmacological evidences on the anti-diabetic and/or anti-hypertensive properties of medicinal plants from various parts of the world, which are used as therapies to concomitantly manage diabetes and hypertension.

AIM OF THE REVIEW

This article reviewed findings on medicinal plants with both anti-diabetic and anti-hypertensive effects reported in same experimental study to facilitate the development of dual-acting therapies against diabetes and hypertension.

MATERIALS AND METHODS

A literature search was carried out on different scientific search engines including, but not limited to "PubMed", "Google Scholar", "Scopus" and ScienceDirect to identify published data in which plants in same experimental studies were reported to possess both anti-hyperglycemic and anti-hypertensive effects. Subsequently, the anti-diabetic/anti-hypertensive potency ratio (ψ) of the medicinal plants was computed.

RESULTS

Sixty-four studies with 102 plant species matched the selection criteria. Members of the Fabaceae family were the most investigated plants, while the ψ greatly varied across the plants, with only 11 plants having a ψ ≃ 1. Withania somnifera Dunal was the only plant reported to show blood glucose-lowering and diuretic effects in humans, comparable to daonil. Caffeic acid, chlorogenic acid, caftaric acid, cichoric acid, verbascoside, leucosceptoside A, isoacteoside, fucoxanthin and nicotinamide were the reported dual acting anti-diabetic and anti-hypertensive compounds identified and/or isolated in the plants.

CONCLUSIONS

This review suggests that medicinal plants possess varied therapeutic dynamics against hypertension and diabetes that could be exploited for the discovery of therapeutic preparation(s) or agent(s) for treating the two diseases.

Synthesis of Rosmarinic Acid Amides as Antioxidative and Hypoglycemic Agents

Type 2 diabetes mellitus (T2DM) is an important metabolic disorder for which there is an urgent need for new antidiabetic drugs. α-Glucosidase inhibition is an established protocol for T2DM therapy. Because hyperglycemia causes oxidative tissue damage, the development of agents with both α-glucosidase inhibition and antioxidant activity from natural or natural-derived polyphenols such derivatives of rosmarinic acid (RA) represents an attractive therapeutic option. We report a study on amides 1-10 derived from RA and their evaluation for yeast α-glucosidase inhibition and antioxidant activity (DPPH and ORAC tests). All amides showed higher inhibitory activity than that of RA, were by far more potent than the antidiabetic drug acarbose, and proved to be effective antioxidants. A molecular docking study displayed significant binding interactions of RA amides with the active site of α-glucosidase. This in silico optimization study led to the design and synthesis of amides 9 (IC50 = 42.3 μM) and 10 (IC50 = 35.2 μM), showing the most potent α-glucosidase inhibition and good antioxidative properties. A kinetic study showed that 10 acts as a mixed type inhibitor.

Secondary metabolite profiling, cytotoxicity, anti-inflammatory potential and in vitro inhibitory activities of Nardostachys jatamansi on key enzymes linked to hyperglycemia, hypertension and cognitive disorders

ETHNOPHARMACOLOGICAL RELEVANCE

Nardostachys jatamansi (D. Don) DC., 'Spikenard' or 'Jatamansi', a highly valued, aromatic herb from alpine Himalayas has a long history of use as ethnomedicine and dietary supplements in Ayurveda, Unani and Chinese system of medicine since Vedic ages (1000-800 BC). In Ayurveda and traditional system of medicine, the species is used as stimulant, sedative, brain tonic or mind rejuvenator, antidiabetic, cardio tonic, and in the treatment of various neurological disorders such as insomnia, epilepsy, hysteria, anxiety and depression. It is considered as Sattvic herb in Ayurveda and is now commercially marketed either as single or poly-herbal formulations by many companies in national and international markets.

AIM OF THE STUDY

The species has become threatened in its natural habitats due to over exploitation and illegal trade of its rhizomes for drug preparation in herbal and pharmaceutical industries. Considering the increasing demand and tremendous medicinal importance of this threatened plant species, a detailed study was undertaken to evaluate its antioxidant potential, secondary metabolite profiling, cytotoxicity, anti-inflammatory potential and in vitro enzyme inhibitory activities on key enzymes linked to hyperglycemia, hypertension and cognitive disorders in different plant parts of wild and in vitro-raised plants with respect to different solvent systems for its sustainable utilization.

MATERIALS AND METHODS

Anti-cholinesterase activity of leaves and rhizome of wild and cultured plant extracts was investigated against both acetylcholinesterase (AChE) and butyrylcholinesterase (BuChE) enzymes. In vitro anti-hyperglycemic (α-amylase and PTP1B), anti-hypertensive (angiotensin-converting enzyme), anti-tyrosinase and anti-inflammatory potential (5-lipoxygenase and hyaluronidase) of different plant parts of wild and in vitro-raised plants with respect to different solvent systems were also evaluated. In vitro cytotoxic effect of rootstock extracts of wild and in vitro-derived plants were against cancer (HCT-116, MCF-7 and OE33) and two normal (HEK and MEF) cell lines. Secondary metabolite profiling of rhizome segments of wild and in vitro-derived plants was carried out by quantitative gas chromatography-mass spectrometry (GC-MS).

RESULTS

In vitro-raised plantlets showed comparative higher yield of various secondary metabolites with a significantly high antioxidant activity as compared to the wild plants. Methanolic rootstock extracts of both wild and in vitro-derived plants of N. jatamansi exhibited significant AChE (IC₅₀ 36.46 ± 2.1 and 31.18 ± 2.6 µg/ml, respectively) and BuChE (IC₅₀ 64.6 ± 3.5 and 60.12 ± 3.6 µg/ml, respectively) inhibitory potential as compared to standard inhibitor galanthamine (IC₅₀ 0.94 ± 0.03 and 4.45 ± 0.5 µg/ml). Methanolic rootstock extract of in vitro-derived plants showed significant α-amylase (IC₅₀ 90.69 ± 2.1 µg/ml), PTP1B (IC₅₀ 24.56 ± 0.8 µg/ml), angiotensin-converting enzyme (IC₅₀ 42.5 ± 3.6 µg/ml) and tyrosinase (IC₅₀ 168.12 ± 3.6 µg/ml) inhibitory potential as compared to standard acarbose (IC₅₀ 52.36 ± 3.1 µg/ml), ursolic acid (IC₅₀ 5.24 ± 0.8 µg/ml), captopril (IC₅₀ 32.36 ± 2.5 µg/ml) and kojic acid (IC₅₀ = 54.44 ± 2.3 µg/ml). Both the methanolic rootstock and leaf extracts of tissue culture-derived plants exhibited promising anti-5-LOX and anti-hyaluronidase activities against the known inhibitor of 5-LOX and hyaluronidase. Furthermore, methanolic rootstock extracts of both wild and in vitro-derived plants exhibited promising cytotoxic effects to HCT-116, MCF-7 and OE33 cell lines as compared to the normal HEK and MEF after 12 h of treatment. Secondary metabolite profiling of wild and in vitro-derived plants by quantitative GC-MS analysis revealed the presence of different classes of terpenoids and phenolic acids might be responsible for its effective biological activities.

CONCLUSION

In vitro-derived plants revealed a substantial anti-cholinesterases, anti-hyperglycemic anti-inflammatory, anti-hypertensive and anti-tyrosinase potential with higher yield of various bioactive metabolites and significantly higher antioxidant activity which substantially explain medicinal importance of N. jatamansi in traditional medicine, used for centuries in different Ayurvedic formulations. The present findings suggest that cultured plants could be a promising alternative for the production of bioactive metabolites with comparative biological activities to the wild plants.