Ethnomedical uses and pharmacological activities of most prevalent species of genus Piper in Panama: A review

Piper auritum ethanol extract is a potent antimutagen against food-borne aromatic amines: mechanisms of action and chemical composition

An ethanol extract of Piper auritum leaves (PAEE) inhibits the mutagenic effect of three food-borne aromatic amines (2-amino-1-methyl-6-phenylimidazo[4,5-b]pyridine (PhIP); 2-amino-3,8-dimethylimidazo[4,5-f]quinoxaline (MeIQx); 2-amino-3,4,8-trimethylimidazo[4,5-f]quinoxaline (4,8-DiMeIQx)) in the TA98 Salmonella typhimurium strain. Preincubation with MeIQx demonstrated in mutagenesis experiments that inhibition of Cytochrome P450 (CYP), as well as direct interaction between component(s) of the plant extract with mutagens, might account for the antimutagenic observed effect. Gas chromatography/mass spectrometry analysis revealed that safrole (50.7%), α-copaene (7.7%), caryophyllene (7.2%), β-pinene (4.2%), γ-terpinene (4.1%), and pentadecane (4.1%) as the main components (PAEE). Piper extract and safrole were able to inhibit the rat liver microsomal CYP1A1 activity that participates in the amines metabolism, leading to the formation of the ultimate mutagenic/ molecules. According to this, safrole and PAEE-inhibited MeIQx mutagenicity but not that of the direct mutagen 2-nitrofluorene. No mutagenicity of plant extract or safrole was detected. This study shows that PAEE and its main component safrole are associated with the inhibition of heterocyclic amines activation due in part to the inhibition of CYP1A subfamily activity.

Undescribed (2-7')-neolignans and polyoxygenated cyclohexene glycosides from the aerial parts of Piper mutabile C. DC. and their inhibitory effects on nitric oxide production

A phytochemical study of the aerial parts of Piper mutabile C. DC. revealed seven undescribed compounds [two (2-7')-neolignans and five polyoxygenated cyclohexene glycosides] and six known propenylcatechol derivatives. The chemical structures of the isolated compounds were elucidated by extensive HR-ESI-MS and NMR analyses, as well as comparison with the literature. The absolute configurations of the (2-7')-neolignans were confirmed by GIAO 13C NMR calculations with a sorted training set strategy and TD-DFT calculation ECD spectra. The (2-7')-neolignans and polyoxygenated cyclohexene glycosides are unusual in natural sources. Undescribed neolignans 1 and 2 inhibited NO production in RAW 264.7 cells, with respective IC50 values of 14.4 and 9.5 μM.

The ameliorative effect of Piper trioicum in attenuating cognitive deficit in scopolamine induced neurotoxicity in experimental rats

ETHNOPHARMACOLOGICAL RELEVANCE

In traditional system of medicine, Piper species, or its components are widely used to treat many diseases including memory improvement. One of the wild species Piper trioicum Roxb. (Piperaceae) is found in South Asian countries. The whole plant is used as folk medicine to improve memory.

AIM OF THE STUDY

To our knowledge, no previous research has investigated the neuroprotective activities of P. trioicum. So, we studied the ameliorative effect of P. trioicum in attenuating cognitive deficit in scopolamine induced neurotoxicity in experimental rats.

MATERIALS AND METHODS

Wistar rats were exposed to scopolamine (3 mg/kg, i. p.) for 14 consecutive days, and the effect of P. trioicum (HAPT; oral, 300, 400 mg/kg) on scopolamine-invoked neurotoxicity in brain were studied. During the experimental period, behaviour analyses of rats were observed 30 min post-drug administration. The role of antioxidants of HAPT in scavenging cellular oxygen/peroxyl radicals were studied. Acetylcholinesterase and butyrylcholinesterase inhibitions, and mode of inhibition kinetics of HAPT were studied. Pathogenic cellular oxidative (MDA, GSH, SOD, and CAT), DNA damage (8-oxodG), neurochemical (acetyl- and, butyryl-cholinesterase), β-secretase (BACE-1 and 2), MAPτ, and neuroinflammation (IL-6, TNF-α) biomarkers in extension to the histopathological observation of brain cortex were studied. GC-MS/MS analysis was carried out to investigate the presence of bioactive constituents in HAPT.

RESULTS

HAPT, a rich source of phenol and flavonoid type antioxidants were responsible in quenching oxygen/peroxyl radicals and protected the cellular membrane, and lipoproteins against ROS in DPPH, ORAC, and CAPe tests. HAPT inhibited acetylcholinesterase and butyrylcholinesterase activities, and showed competitive-inhibition (reversible) towards cholinesterase activities. HAPT-400 significantly improved the learning and memory-impairment by restoring oxidative MDA, GSH, SOD, CAT, and DNA damage (8-oxodG) markers of serum, and cortex. It also improved acetyl- and, butyryl-cholinesterase, β-secretase, and MAPτ level in brain by restoring proinflammatory cytokines IL-6, and TNF-α indicators in neurotoxic rats. GC-MS/MS reported therapeutic significance active compounds were molecular-docked towards target proteins, found that proscillaridin showed the highest affinity towards AChE, BuChE, BACE1, and BACE2 with binding energy of ΔGb -9.1, ΔGb -10.2, ΔGb -11.4 and ΔGb -11.5 Kcal/mol, respectively. Cymarin and morphine-3-glucuronide showed the second highest binding affinity towards AChE (ΔGb -8.8) and BuChE (ΔGb -10.0), respectively. In BACE-1, betulin showed the second highest binding affinity ΔGb -10.7 Kcal/mol and in BACE-2, morphine-3-glucuronide showed the second highest binding affinity ΔGb -9.8 Kcal/mol.

CONCLUSIONS

Synergistic impact of proscillaridin, Cymarin, morphine-3-glucuronide, betulin like compounds in HAPT improved memory impairment, healing of tissue architecture of cortex with the restoration of neurochemical, neuroinflammation, and oxidative indicators in neurotoxic rats.

Antifungal Constituents of Piper crocatum and Their Activities as Ergosterol Biosynthesis Inhibitors Discovered via In Silico Study Using ADMET and Drug-Likeness Analysis

Along with the increasing resistance of Candida spp. to some antibiotics, it is necessary to find new antifungal drugs, one of which is from the medicinal plant Red Betel (Piper crocatum). The purpose of this research is to isolate antifungal constituents from P. crocatum and evaluate their activities as ergosterol biosynthesis inhibitors via an in silico study of ADMET and drug-likeness analysis. Two new active compounds 1 and 2 and a known compound 3 were isolated, and their structures were determined using spectroscopic methods, while their bioactivities were evaluated via in vitro and in silico studies, respectively. Antifungal compound 3 was the most active compared to 1 and 2 with zone inhibition values of 14.5, 11.9, and 13.0 mm, respectively, at a concentration of 10% w/v, together with MIC/MFC at 0.31/1.2% w/v. Further in silico study demonstrated that compound 3 had a stronger ΔG than the positive control and compounds 1 and 2 with -11.14, -12.78, -12.00, and -6.89 Kcal/mol against ERG1, ERG2, ERG11, and ERG24, respectively, and also that 3 had the best Ki with 6.8 × 10-3, 4 × 10-4, 1.6 × 10-3, and 8.88 μM. On the other hand, an ADMET analysis of 1-3 met five parameters, while 1 had one violation of Ro5. Based on the research data, the promising antifungal constituents of P. crocatum allow P. crocatum to be proposed as a new antifungal candidate to treat and cure infections due to C. albicans.

Effect of ethanolic extracts from Piperaceae leaves on the reduction of skin necrosis and wound healing in an animal model of degloving injuries

PURPOSE

To assess the effect of the ethanolic extract of the leaves of three species of plants from the Piperaceae family on reducing necrosis and enhancing wound healing in an animal model of degloving injuries.

METHODS

The animals were divided into six groups, each consisting of six animals: sham, negative control, EEPA (Piper amalago ethanolic extract), EEPG (Piper glabratum ethanolic extract), EEPV (Piper vicosanum ethanolic extract), and positive control receiving hyperbaric oxygenation. The animals underwent surgery to induce excision wounds, and the extent of cutaneous necrosis was evaluated using graphic software, while wound healing was assessed through histopathology.

RESULTS

Skin necrosis percentage area was: sham group = 62.84% 6.38; negative control group = 63.03% 4.11; P. vicosanum = 40.80% 4.76 p < 0.05; P. glabratum 32.97% 4.01 p < 0.01; P. amalago = 32.40% 4.61 p < 0.01; hyperbaric oxygenation = 33.21% 4.29 p < 0.01. All treated groups showed higher collagen deposition and less intense, plus predominantly mononuclear inflammatory infiltrate, suggesting improved healing process.

CONCLUSIONS

The three tested extracts demonstrated efficacy in reducing the extent of cutaneous necrosis caused by degloving injuries and also showed evidence of improvement in the wound healing process.

Recent advances in the discovery of plant-derived antimicrobial natural products to combat antimicrobial resistant pathogens: insights from 2018-2022

Covering: 2018 to 2022Antimicrobial resistance (AMR) poses a significant global health threat. There is a rising demand for innovative drug scaffolds and new targets to combat multidrug-resistant bacteria. Before the advent of antibiotics, infections were treated with plants chosen from traditional medicine practices. Of Earth's 374 000 plant species, approximately 9% have been used medicinally, but most species remain to be investigated. This review illuminates discoveries of antimicrobial natural products from plants covering 2018 to 2022. It highlights plant-derived natural products with antibacterial, antivirulence, and antibiofilm activity documented in lab studies. Additionally, this review examines the development of novel derivatives from well-studied parent natural products, as natural product derivatives have often served as scaffolds for anti-infective agents.

Metabolomic analysis of Thai Herbal Analgesic Formula based on ultra-high-performance liquid chromatography-quadrupole time-of-flight mass spectrometry

Sahatsatara formula (STF), a Thai herbal medicine formula which has been commonly used as analgesic drugs to relieve musculoskeletal pain and numbness in Thai traditional medicine. The pharmacological studies of its ingredients have represented that have anti-inflammatory and antioxidant properties. However, the quality markers (Q-markers) for STF are still unknown and require further investigation. The primary goal of this study was to establish the chemical profile of STF though metabolomic analysis. Untargeted metabolomics were used to analyze global components and accurately qualify compounds. Multivariate analysis (MVA) was used to classify STF extract at three different concentrations and a quality control sample. Furthermore, samples' characteristics and identification-related markers were observed and compounds matched to the Traditional Chinese medicine library in UNIFI software. According to the results, chemical analysis revealed 63 compounds in positive mode and 33 compounds in negative mode within STF. Notably, 19 potential Q-markers were tentative identified in all three concentrations of STF, including alkaloids, terpenes, phenols, organic acids, disaccharides, fatty acids, glycosides, quinonoids, and steroids. The compounds exhibited pharmacological effects such as anti-inflammatory activity, anti-oxidant activity, and analgesic properties, which correlated to traditional properties of STF. Consequently, this study provides insights into the chemical profiles of the STF and identifies potential markers that can be utilized for qualitative and quantitative quality control of STF. Additionally, the findings can also be useful for further research into STF's anti-inflammatory properties through in vitro assays, as well as exploring its clinical efficacy to support evidence-based medicine for STF.

Deciphering anti-infectious compounds from Peruvian medicinal Cordoncillos extract library through multiplexed assays and chemical profiling

High prevalence of parasitic or bacterial infectious diseases in some world areas is due to multiple reasons, including a lack of an appropriate health policy, challenging logistics and poverty. The support to research and development of new medicines to fight infectious diseases is one of the sustainable development goals promoted by World Health Organization (WHO). In this sense, the traditional medicinal knowledge substantiated by ethnopharmacology is a valuable starting point for drug discovery. This work aims at the scientific validation of the traditional use of Piper species ("Cordoncillos") as firsthand anti-infectious medicines. For this purpose, we adapted a computational statistical model to correlate the LCMS chemical profiles of 54 extracts from 19 Piper species to their corresponding anti-infectious assay results based on 37 microbial or parasites strains. We mainly identified two groups of bioactive compounds (called features as they are considered at the analytical level and are not formally isolated). Group 1 is composed of 11 features being highly correlated to an inhibiting activity on 21 bacteria (principally Gram-positive strains), one fungus (C. albicans), and one parasite (Trypanosoma brucei gambiense). The group 2 is composed of 9 features having a clear selectivity on Leishmania (all strains, both axenic and intramacrophagic). Bioactive features in group 1 were identified principally in the extracts of Piper strigosum and P. xanthostachyum. In group 2, bioactive features were distributed in the extracts of 14 Piper species. This multiplexed approach provided a broad picture of the metabolome as well as a map of compounds putatively associated to bioactivity. To our knowledge, the implementation of this type of metabolomics tools aimed at identifying bioactive compounds has not been used so far.

Antiquorum and Antibiofilm Activities of Piper bogotense C. DC. against Pseudomonas aeruginosa and Identification of Bioactive Compounds

The present study describes the anti-biofilm and quorum sensing (QS) inhibitory potential of extracts and chemical constituents from Piper bogotense. Antibiofilm potential was determined through crystal violet assay against Pseudomonas aeruginosa, while QS inhibition efficacy was determined through violacein inhibition assay using Chromobacterium violaceum as a bacterial model. Additionally, this study reports the effects of the chemical constituents isolated in P. bogotense against various virulent factors associated with QS, such as the percentage decrease in pyocyanin, elastase, and protease production. The chemical study led to the isolation and identification of two prenylated benzoic acids (1 and 2) and a prenylated hydroquinone 3, of which compounds 1 and 2 are reported for the first time for P. bogotense. The ethanolic extract and the DCM fraction from P. bogotense stand out for reducing violacein production in C. violaceum, as well as the biofilm formation in P. aeruginosa. Compounds 2 and 3 stand out for having the lowest violacein production (43.8% and 68.3%), as well as the lowest production of virulence factors such as elastase (60.2% and 51.4%) and pyocyanin (39.7% and 33.2%). These results demonstrate the potential of P. bogotense components to be used as an alternative control against multidrug-resistant P. aeruginosa.

Phytochemical profiling of Piper crocatum and its antifungal mechanism action as Lanosterol 14 alpha demethylase CYP51 inhibitor: a review

Mycoses or fungal infections are general health problem that often occurs in healthy and immunocompromised people in the community. The development of resistant strains in Fungi and the incidence of azole antibiotic resistance in the Asia Pacific which reached 83% become a critical problem nowadays. To control fungal infections, substances and extracts isolated from natural resources, especially in the form of plants as the main sources of drug molecules today, are needed. Especially from Piperaceae, which have long been used in India, China, and Korea to treat human ailments in traditional medicine. The purpose of this review is to describe the antifungal mechanism action from Piper crocatum and its phytochemical profiling against lanosterol 14a demethylase CYP51. The methods used to search databases from Google Scholar to find the appropriate databases using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Flow Diagram as a clinical information retrieval method. From 1.150.000 results searched by database, there is 73 final results article to review. The review shows that P. crocatum contains flavonoids, tannins, terpenes, saponins, polyphenols, eugenol, alkaloids, quinones, chavibetol acetate, glycosides, triterpenoids or steroids, hydroxychavikol, phenolics, glucosides, isoprenoids, and non-protein amino acids. Its antifungal mechanisms in fungal cells occur due to ergosterol especially lanosterol 14a demethylase (CYP51) inhibition, which is one of the main target sites for antifungal activity because it functions to maintain the integrity and function of cell membranes in Candida. P. crocatum has an antifungal activity through its phytochemical profiling against fungal by inhibiting the lanosterol 14a demethylase, make damaging cell membranes, fungal growth inhibition, and fungal cell lysis.

Essential Oils from Colombian Plants: Antiviral Potential against Dengue Virus Based on Chemical Composition, In Vitro and In Silico Analyses

Currently, there are no therapies to prevent severe dengue disease. Essential oils (EOs) can serve as primary sources for research and the discovery of phytomedicines for alternative therapy. Fourteen EOs samples were obtained by distillation from six plants used in Colombian folk medicine. GC/MS analysis identified 125 terpenes. Cytopathic effect (CPE) reduction assays revealed differences in antiviral activity. EOs of Lippia alba, citral chemotype and carvone-rich fraction; Lippia origanoides, phellandrene chemotype; and Turnera diffusa, exhibited strong antiviral activity (IC50: 29 to 82 µg/mL; SI: 5.5 to 14.3). EOs of Piper aduncum, Ocimum basilicum, and L. origanoides, carvacrol, and thymol chemotypes, exhibited weak antiviral activity (32 to 53% DENV-CPE reduction at 100 µg/mL; SI > 5.0). Cluster and one-way ANOVA analyses suggest that the strong antiviral activity of EOs could be attributed to increased amounts of non-phenolic oxygenated monoterpenes and sesquiterpene hydrocarbons. Docking analyses (AutoDock Vina) predicted binding affinity between the DENV-2 E protein and terpenes: twenty sesquiterpene hydrocarbons (−8.73 to −6.91 kcal/mol), eight oxygenated monoterpenes (−7.52 to −6.98 kcal/mol), and seven monoterpene hydrocarbons (−7.60 to −6.99 kcal/mol). This study reports for the first time differences in the antiviral activity of EOs against DENV, corresponding to their composition of monoterpenes and sesquiterpenes.

A Review of Bioactive Compounds and Antioxidant Activity Properties of Piper Species

Antioxidants are compounds that are able to inhibit the negative effects that come from free radicals. The phenomenon of imbalanced antioxidant production and the accumulation of free radicals in cells and tissues can cause oxidative stress. Excessive free radicals that enter the body cannot be warded off by endogenous antioxidant compounds so that the required antioxidant compounds can come from the outside, which helps in the performance of endogenous antioxidants. Antioxidants that come from outside consist of synthetic and natural antioxidants; however, synthetic antioxidants are not an option because they have toxic and carcinogenic effects. Therefore, the use of natural ingredients is an alternative method that is needed to create a new natural antioxidant compound. Piper species are being considered as possible medicinal plants for the development of new sources of antioxidants. Several studies have been carried out starting from the extract levels, fractions, and compounds of the Piper species, which showed good antioxidant activity. Currently, some of these plants are being used as ingredients in traditional medicines to treat allergies, toothaches, and coughs. This review examines the distribution, botanical data, pharmacology, especially antioxidant activity, and the compounds contained in five Piper species, namely Piper amalago L., Piper betle L., Piper hispidum Sw., Piper longum L., and Piper umbellatum L.

Phytochemical profiling of Piper crocatum and its antifungal mechanism action as Lanosterol 14 alpha demethylase CYP51 inhibitor: a review

Mycoses or fungal infections are a general health problem that often occurs in healthy and immunocompromised people in the community. The development of resistant strains in Fungi and the incidence of azole antibiotic resistance in the Asia Pacific which reached 83% become a critical problem nowadays. To control fungal infections, substances and extracts isolated from natural resources, especially in the form of plants as the main sources of drug molecules today, are needed. Especially from Piperaceae, which have long been used in India, China, and Korea to treat human ailments in traditional medicine. The purpose of this review is to describe the antifungal mechanism action from Piper crocatum and its phytochemical profiling against lanosterol 14a demethylase CYP51. The methods used to search databases from Google Scholar to find the appropriate databases using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) Flow Diagram as a clinical information retrieval method. From 1.150.000 results searched by database, there is 73 final results article to review. The review shows that P. crocatum contains flavonoids, tannins, terpenes, saponins, polyphenols, eugenol, alkaloids, quinones, chavibetol acetate, glycosides, triterpenoids or steroids, hydroxychavikol, phenolics, glucosides, isoprenoids, and non-protein amino acids. Its antifungal mechanisms in fungal cells occur due to ergosterol, especially lanosterol 14a demethylase (CYP51) inhibition, which is one of the main target sites for antifungal activity because it functions to maintain the integrity and function of cell membranes in Candida. P. crocatum has an antifungal activity through its phytochemical profiling against fungal by inhibiting the lanosterol 14a demethylase, make damaging cell membranes, fungal growth inhibition, and fungal cell lysis.

Phytochemical profiling of Piper crocatum and its antifungal activity as Lanosterol 14 alpha demethylase CYP51 inhibitor: a review

Mycoses or fungal infections are a general health problem that often occurs in healthy and immunocompromised people in the community. The development of resistant strains in Fungi and the incidence of azole antibiotic resistance in the Asia Pacific which reached 83% become a critical problem nowadays. To control fungal infections, substances and extracts isolated from natural resources, especially in the form of plants as the main sources of drug molecules today, are needed. Especially from Piperaceae, which have long been used in India, China, and Korea to treat human ailments in traditional medicine. The purpose of this review was to describe antifungal activity from Piper crocatum and its phytochemical profiling against lanosterol 14 alpha demethylase CYP51. The methods used search databases from Google Scholar to find the appropriate databases using Preferred Reporting Items for Systematic Reviews and Meta-analyses (PRISMA) flow diagram as a clinical information retrieval method. From 1,150,000 results search by database, there were 73 selected articles to review. The review shows that P. crocatum contains flavonoids, tannins, terpenes, saponins, polyphenols, eugenol, alkaloids, quinones, chavibetol acetate, glycosides, triterpenoids or steroids, hydroxychavikol, phenolics, glucosides, isoprenoids, and non-protein amino acids. Its antifungal mechanisms in fungal cells occur due to ergosterol especially lanosterol 14 alpha demethylase CYP51 inhibition as a result of 5,6 desaturase (ERG3) downregulation. P. crocatum has an antifungal activity by its phytochemical profiling that act against fungi by inhibiting the fungal cytochrome P 450 pathway, make damaging cell membranes, fungal growth inhibition, morphological changes, and fungal cell lysis.

Involvement of a neutrophil-mast cell axis in the effects of Piper malacophyllum (C. PESL) C. DC extract and its isolated compounds in a mouse model of dysmenorrhoea

The effects of Piper malacophyllum (C. Pesl) C. DC extracts and its isolated compounds were analysed in a mouse model of primary dysmenorrhoea (PD). Female Swiss mice (6-8 weeks old) on proestrus were intraperitoneally treated with estradiol benzoate for 3 days, to induce PD. Twenty-four hours later, animals were treated 24 h later with vehicle, plant extract, gibbilimbol B, 4,6-dimethoxy-5-E-phenylbutenolide, mixture of 4,6-dimethoxy-5-E-phenylbutenolide and 4,6-dimethoxy-5-Z-phenylbutenolide, or ibuprofen. One hour later, oxytocin was injected and the numbers of abdominal writhing were counted. Then, mice were euthanized and uteri were collected for morphometrical and histological analyses. The effects of P. malacophyllum in inflammation were investigated in mouse peritoneal neutrophils culture stimulated with LPS or fMLP (chemotaxis and mediator release). Finally, uterus contractile and relaxing responses were assessed. Similar to ibuprofen, P. malacophyllum extract and isolated compounds reduced abdominal writhing in mice with PD. Histology indicated a marked neutrophil and mast cell infiltrate in the uterus of PD animals which was attenuated by the extract. The compounds and the extract reduced neutrophil chemotaxis and inflammatory mediator release by these cells. Reduced TNF levels were also observed in uteri of PD mice treated with P. malacophyllum. The extract did not affect spontaneous uterine contractions nor those induced by carbachol or KCl. However, it caused relaxation of oxytocin-induced uterine contraction, an effect blunted by H1 receptor antagonist. Overall the results indicate that P. malacophyllum may represent interesting natural tools for reliving PD symptoms, reducing the triad of pain, inflammation and spasmodic uterus behaviour.

Selection and validation of reference genes for measuring gene expression in Piper species at different life stages using RT-qPCR analysis

The secondary metabolism of Piper species is known to produce a myriad of natural products from various biosynthetic pathways which, represent a rich source of previously uncharacterized chemical compounds. The determination of gene expression profiles in multiple tissue/organ samples could provide valuable clues towards understanding the potential biological functions of chemical changes in these plants. Studies on gene expression by RT-qPCR require particularly careful selection of suitable reference genes as a control for normalization. Here, we provide a study for the identification of reliable reference genes in P. arboreum, P. gaudichaudianum, P. malacophyllum, and P. tuberculatum, at two different life stages: 2-month-old seedlings and adult plants. To do this, annotated sequences were recovered from transcriptome datasets of the above listed Piper spp. These sequences were subjected to expression analysis using RT-qPCR, followed by analysis using the geNorm and NormFinder algorithms. A set of five genes were identified showing stable expression: ACT7 (Actin-7), Cyclophilin (Peptidyl-prolyl cis-trans isomerase), EF1α (Elongation factor 1-alpha), RNABP (RNA-binding protein), and UBCE (Ubiquitin conjugating enzyme). The universality of these genes was then validated using two target genes, ADC (arginine decarboxylase) and SAMDC (S-adenosylmethionine decarboxylase), which are involved in the biosynthesis of polyamines. We showed that normalization genes varied according to Piper spp., and we provide a list of recommended pairs of the best combination for each species. This study provides the first set of suitable candidate genes for gene expression studies in the four Piper spp. assayed, and the findings will facilitate subsequent transcriptomic and functional gene research.

Evaluation of the safety of ethanolic extract from Piper amalago L. (Piperaceae) leaves in vivo: Subacute toxicity and genotoxicity studies

Piper amalago L. (Piperaceae) is traditionally used due to its anti-inflammatory, analgesic, diuretic, and antiparasitic properties. However, few studies have focused on its adverse effects, compromising its safe use. This study evaluated the toxicological safety of ethanolic extract from Piper amalago leaves (EEPA), through subacute toxicity and genotoxicity assays in rodents. In subacute toxicity, 100, 200 or 300 mg/kg of EEPA were tested in female Wistar rats, by gavage, for 28 days. For genotoxicity test, female Swiss mice were orally treated with 17.5, 175 or 1750 mg/kg of EEPA and the comet, micronucleus, and splenic phagocytic assays were evaluated. In subacute toxicity, the extract induced an increase in the food and water intakes, as well as in the liver absolute weight, and in the heart and kidney relative weights. EEPA also provoked alterations in histopathological analysis of liver and in hemato-biochemical parameters, evidenced by a decrease in hematocrit levels and albumin levels, and an increase in the number of platelets and in alkaline phosphatase and cholesterol levels. However, EEPA did not presented genotoxic nor mutagenic properties. EEPA showed hemato-biochemical toxicity profile in rats and should be used with caution, especially when for prolonged period.

Synergistic potential of essential oils with antibiotics to combat fungal pathogens: Present status and future perspectives

The steady rise in the emergence of antibiotic-resistant fungal pathogens has rendered most of the clinical antibiotics available in the market to be ineffective. Therefore, alternative strategies are required to tackle drug-resistant fungal infections. An effective solution is to combine the available antibiotics with adjuvants such as phytochemicals or essential oils to enhance the efficacy and activity of antibiotics. The present review aims to summarize the studies on synergistic combinations of essential oils and anti-fungal antibiotics. The current findings, methods used for measuring synergistic effects, possible mechanisms of synergism, and future perspectives for developing synergistic EO-antibiotic therapeutic formulations are discussed in this study. Several essential oils exhibit synergistic effect in combination with antibiotics against human fungal pathogens such as Candida albicans. The possible mechanisms of synergy exhibited by essential oil- antibiotic combinations in fungi include disruption of cell wall structure/ ergosterol biosynthesis pathway, enhanced transdermal penetration of antibiotics, alterations in membrane permeability, intracellular leakage of cellular contents, inhibition of germ tube formation or fungal biofilm formation, and competition for a primary target. Synergistic combination of essential oils and antibiotics can prove to be a valid and pragmatic alternative to develop drugs with increased drug-efficacy, and low toxicity.

Essential Oil and Major Non-Volatile Secondary Metabolites from the Leaves of Amazonian Piper subscutatum

The essential oil and the major non-volatile secondary metabolites from the leaves of Piper subscutatum (Miq.) C. DC. (Family Piperaceae), collected in the Ecuadorian Amazon, were analyzed for the first time in the present study. The essential oil was submitted to chemical and enantioselective analyses by GC-MS and GC-FID. (E)-β-caryophyllene (25.3-25.2%), β-chamigrene (10.3-7.8%), (E)-nerolidol (8.1-7.7%), β-selinene (7.2-7.7%), δ-cadinene (2.7-3.9%), bicyclogermacrene (3.7-2.4%), and β-pinene (2.6-3.4%) were the major components. The enantioselective analysis, carried out on a β-cyclodextrin-based column, showed four scalemic mixtures in which (1R,5R)-(+)-α-pinene, (1S,5S)-(-)-β-pinene, (S)-(-)-limonene, and (1R,2S,6S,7S,8S)-(-)-α-copaene were the major enantiomers, with enantiomeric excesses of 28.8%, 77.8%, 18.4%, and 6.0%, respectively. The study was complemented with the chemical analysis of the organic fraction dissolved in the hydrolate, whose major components were 6-methyl-5-hepten-2-one (63.7-64.4%) and linalool (6.5-6.0%). Concerning the non-volatile fraction, five lignans were the major components. (-)-Beilshminol B, (-)-grandisin, (-)-3',4'-methylenedioxy-3,4,5-trimethoxy-7,7'-epoxylignan, (-)-3',4'-methylenedioxy-3,4,5,5'-tetramethoxy-7,7'-epoxylignan, and (-)-3,4,3',4'-dimethylenedioxy-5,5'-dimethoxy-7,7'-epoxylignan were identified by means of NMR spectroscopy, mass spectrometry and X-ray crystallography. The absolute configuration 7S,8S,7'S,8'S was tentatively assigned to all of them.

Efficient extraction of bioactive flavonoids from Celtis sinensis leaves using deep eutectic solvent as green media

In recent years, deep eutectic solvent (DES) has attracted comprehensive attention on the extraction of natural products, and is regarded as an alternative to traditional organic solvents for the environmental advantages. Twenty-six DESs were compared for their extraction yield of total flavonoids and isovitexin (the main flavonoid in Celtis sinensis) from Celtis sinensis. The results show that the extraction yields of total flavonoids by betaine/glycolic acid (DES8), ethylamine hydrochloride/1,2-propanediol (DES12) and tetrapropylammonium bromide/lactic acid (DES17) are the highest, while the extraction yields of isovitexin by ethylene glycol/malonic acid (DES23), ethylene glycol/glycolic acid (DES24) and 1,2-propanediol/glycolic acid (DES26) are the highest. The extraction conditions using the above six DESs were further optimized systematically. Under optimum conditions, the extraction rates of total flavonoids and isovitexin can be increased up to 95.39 and 10.58 mg g⁻¹, respectively, which were significantly higher than that of methanol extraction. In order to exclude the effect of DESs on the bioactivity of Celtis sinensis extract, the macroporous resin D-101 was used to purify the total flavonoids from DESs extract, and the recovery rates of flavonoids from the above six kinds of DESs were all over 80%. Next, the anti-inflammatory activity of DES extracts was compared using a lymphocyte transformation experiment. The result showed that the inhibition rate of the DES24 extract on the proliferation of Con A-activated T cells was up to 72% with an IC₅₀ value of 124.8 μg mL⁻¹. None of the DESs extracted exhibited cytotoxicity on normal T cells. The mechanism of the anti-inflammatory activity against Con A-activated T cells may be that DES24 flavonoids extract induced the apoptosis of inflammatory T cells, and activated the expression of pro-apoptotic protein. Taken together, DES has showed significant advantages on the extraction of natural products for the relatively mild extraction condition, high yield and environmental-friendliness.

In recent years, deep eutectic solvent (DES) has attracted comprehensive attention on the extraction of natural products, and is regarded as an alternative to traditional organic solvents for the environmental advantages.

A systematic review of botany, phytochemicals and pharmacological properties of "Hoja sant a" (Piper auritum Kunth)

Hoja santa (Piper auritum) refers to an important presence in Mexican cuisine. The information of this review article was gathered from several electronic sources such as Scopus, Medline, Scielo, ScienceDirect, SciFinder, Web of Science, Google Scholar and Lilacs. Phytochemical studies have revealed the presence of benzoic acid derivatives, phenylpropanoids and triterpenoids, while the essential oils have shown its richness in safrole, hence it has several activities, such as antioxidant, toxicity, insecticidal, anti-diabetic and cytotoxic properties. This review is expected to draw the attention of medical professionals and the general public towards P. auritum as well as to open the door for detailed research in the future.

Secondary Metabolic Profile as a Tool for Distinction and Characterization of Cultivars of Black Pepper (Piper nigrum L.) Cultivated in Pará State, Brazil

This study evaluated the chemical compositions of the leaves and fruits of eight black pepper cultivars cultivated in Pará State (Amazon, Brazil). Hydrodistillation and gas chromatography-mass spectrometry were employed to extract and analyze the volatile compounds, respectively. Sesquiterpene hydrocarbons were predominant (58.5-90.9%) in the cultivars "Cingapura", "Equador", "Guajarina", "Iaçará", and "Kottanadan", and "Bragantina", "Clonada", and "Uthirankota" displayed oxygenated sesquiterpenoids (50.6-75.0%). The multivariate statistical analysis applied using volatile composition grouped the samples into four groups: γ-Elemene, curzerene, and δ-elemene ("Equador"/"Guajarina", I); δ-elemene ("Iaçará"/"Kottanadan"/"Cingapura", II); elemol ("Clonada"/"Uthirankota", III) and α-muurolol, bicyclogermacrene, and cubebol ("Bragantina", IV). The major compounds in all fruit samples were monoterpene hydrocarbons such as α-pinene, β-pinene, and limonene. Among the cultivar leaves, phenolics content (44.75-140.53 mg GAE·g^-1 FW), the enzymatic activity of phenylalanine-ammonia lyase (20.19-57.22 µU·mL^-1), and carotenoids (0.21-2.31 µg·mL^-1) displayed significant variations. Due to black pepper's susceptibility to Fusarium infection, a molecular docking analysis was carried out on Fusarium protein targets using each cultivar's volatile components. F. oxysporum endoglucanase was identified as the preferential protein target of the compounds. These results can be used to identify chemical markers related to the susceptibility degree of black pepper cultivars to plant diseases prevalent in Pará State.

Metabolomic approach of the antiprotozoal activity of medicinal Piper species used in Peruvian Amazon

ETHNOPHARMACOLOGICAL RELEVANCE

In the Peruvian Amazon as in the tropical countries of South America, the use of medicinal Piper species (cordoncillos) is common practice, particularly against symptoms of infection by protozoal parasites. However, there is few documented information about the practical aspects of their use and few scientific validation. The starting point of this work was a set of interviews of people living in six rural communities from the Peruvian Amazon (Alto Amazonas Province) about their uses of plants from Piper genus: one community of Amerindian native people (Shawi community) and five communities of mestizos. Infections caused by parasitic protozoa take a huge toll on public health in the Amazonian communities, who partly fight it using traditional remedies. Validation of these traditional practices contributes to public health care efficiency and may help to identify new antiprotozoal compounds.

AIMS OF STUDY

To record and validate the use of medicinal Piper species by rural people of Alto Amazonas Province (Peru) and annotate active compounds using a correlation study and a data mining approach.

MATERIALS AND METHODS

Rural communities were interviewed about traditional medication against parasite infections with medicinal Piper species. Ethnopharmacological surveys were undertaken in five mestizo villages, namely: Nueva Arica, Shucushuyacu, Parinari, Lagunas and Esperanza, and one Shawi community (Balsapuerto village). All communities belong to the Alto Amazonas Province (Loreto region, Peru). Seventeen Piper species were collected according to their traditional use for the treatment of parasitic diseases, 35 extracts (leaves or leaves and stems) were tested in vitro on P. falciparum (3D7 chloroquine-sensitive strain and W2 chloroquine-resistant strain), Leishmania donovani LV9 strain and Trypanosoma brucei gambiense. Assessments were performed on HUVEC cells and RAW 264.7 macrophages. The annotation of active compounds was realized by metabolomic analysis and molecular networking approach.

RESULTS

Nine extracts were active (IC₅₀ ≤ 10 μg/mL) on 3D7 P. falciparum and only one on W2 P. falciparum, six on L. donovani (axenic and intramacrophagic amastigotes) and seven on Trypanosoma brucei gambiense. Only one extract was active on all three parasites (P. lineatum). After metabolomic analyses and annotation of compounds active on Leishmania, P. strigosum and P. pseudoarboreum were considered as potential sources of leishmanicidal compounds.

CONCLUSIONS

This ethnopharmacological study and the associated in vitro bioassays corroborated the relevance of use of Piper species in the Amazonian traditional medicine, especially in Peru. A series of Piper species with few previously available phytochemical data have good antiprotozoal activity and could be a starting point for subsequent promising work. Metabolomic approach appears to be a smart, quick but still limited methodology to identify compounds with high probability of biological activity.

Piper sarmentosum Roxb.: A review on its botany, traditional uses, phytochemistry, and pharmacological activities

ETHNOPHARMACOLOGICAL RELEVANCE

Piper sarmentosum Roxb. (Piperaceae) is a traditional medicinal plant widely distributed in India, Malaysia, Thailand, and the southeastern coastal areas of China including Fujian, Guangdong, and Guizhou. It has been used for centuries for the treatment of wind-cold cough, fever, rheumatism arthralgia, diarrhea dysentery, postpartum foot swelling, stomachache, toothache, diabetes, and traumatic injury.

AIMS OF THE REVIEW

To critically anayze the literature for the botany, traditional uses, phytochemistry, pharmacology, toxicity, and clinical trials of P. sarmentosum in order to provide a scientific consensus for further research and discovery of potential candidate drugs.

MATERIALS AND METHODS

The contents of this review were sourced from electronic databases including PubMed, SciFinder, Web of Science, Science Direct, Elsevier, Google Scholar, Chinese Knowledge On frastructure (CNKI), Wanfang, Chinese Scientific and Technological Periodical Database (VIP), Chinese Biomedical Database (CBM), Cochrane Controlled register of Clinical Trials, Clinical Trials. gov, and Chinese Clinical Trial Registry. Chinese medicine books published over the years were used to elucidate the traditional uses of P. sarmentosum and additional information was also collected from Yao Zhi website (https://db.yaozh.com/).

RESULTS

Phytochemical analyses of the chemical constituents of P. sarmentosum include essential oil, alkaloids, flavonoids, lignans, and steroids. The literature supports the ethnomedicinal uses of P. sarmentosum for the treatment of cold, gastritis, and rheumatoid joint pain, and further confirms its relatively new pharmacological activities, including anti-inflammatory, antineoplastic, and antipyretic activities. Other biological roles such as anti-osteoporosis, antibacterial, antidepressant, anti-atherosclerotic, and hypoglycemic activities have also been reported. However, the methodologies employed in individual studies are limited.

CONCLUSIONS

There is convincing evidence from both in vitro and in vivo studies supporting the traditional use of P. sarmentosum and it is imperative that natural bioactive compounds are examined further. More efforts should be focused on the pharmacodynamic constituents of P. sarmentosum to provide practical basis for quality control, and additional studies are needed to understand the mechanism of their action. Further studies on the comprehensive evaluation of medicinal quality and understandings of serum chemistry, multi-target network pharmacology, and molecular docking technology of P. sarmentosum are of great importance and should be considered.

Piper umbellatum L. (Piperaceae): Phytochemical profiles of the hydroethanolic leaf extract and intestinal anti-inflammatory mechanisms on 2,4,6 trinitrobenzene sulfonic acid induced ulcerative colitis in rats

ETHNOPHARMACOLOGICAL RELEVANCE

Piper umbellatum L. leaves, commonly found in the Amazon, Cerrado and Atlantic rain forest regions of Brazil, are widely used as a traditional medicine to treat gastrointestinal disorders and inflammation, among others diseases. Also, previous scientific studies demonstrated that P. umbellatum has gastroprotective and anti-inflammatory activity.

AIM

To investigate the phytochemical profiles and the intestinal anti-inflammatory effect of the hydroethanolic extract of P. umbellatum (HEPu) leaf on ulcerative colitis in rats.

MATERIALS AND METHODS

In this study, the chemical composition of HEPu was analyzed by gas chromatography-mass spectrometry (GC-MS) and liquid chromatography coupled to mass spectrometry (LC/MS). Also, this work studied the effects of HEPu on ulcerative colitis induced by 2,4,6-trinitrobenzene sulfonic acid (TNBS, 30 mg/mL in 20% ethanol) by intrarectal administration in rats. Simultaneously, animals were pre-treated orally with HEPu (30, 100 and 300 mg/kg), mesalazine (500 mg/kg), or vehicle. At the end of the experimental period, clinical signs of ulcerative colitis were evaluated by determination of weight loss, gross appearance, ulcer area and histological changes. Reduced glutathione (GSH), lipoperoxides (MDA) and nitric oxide (NO) levels, and superoxide dismutase (SOD), myeloperoxidase (MPO) and catalase (CAT) activities were determined in colon tissues. Also, pro-inflammatory mediators such as tumor necrosis factor alpha (TNF-α) and interleukin 1 beta (IL- 1β) were quantified by immunoassay on the surface of fluorescent-coded magnetic beads (Luminex MagPix System).

RESULTS

GC-MS analysis showed the presence of 17 different phytochemical compounds in the HEPu. LC/MS analyses revealed the presence of compounds in HEPu as protocatechuic acid, ferulic acid, kaempferol, rosmarinic acid, apigenin and ursolic acid. Treatment with HEPu significantly ameliorated weight loss, macroscopic damage, ulcerated area and histopathological changes such as sub-mucosal edema, cell infiltration, ulceration and necrosis (p < 0.001). Furthermore, HEPu (30, 100, and 300 mg/kg, p.o) inhibited the levels of oxidative parameters, such as MPO (49%, 53%, and 62%, p < 0.001), NO (20%, 19%, 22%, p < 0.01), and MDA (75%, 83%, 70%, p < 0.001), whereas increased the antioxidant activities such as SOD (208%, 192%, 64%, p < 0.001), GSH (94%, 75%, 49%, p < 0.01), and CAT (92%, 69%, 108%, p < 0.01). The extract also inhibited the pro-inflammatory cytokines TNF-α (81%, 85%, 85%, p < 0.001) and IL-1β (95%, 79%, 89%, p < 0.001) levels.

CONCLUSION

Together, these results revealed that P. umbellatum L. is a promising source of metabolites to be used in the treatment of inflammatory bowel disease.

Dillapiole in Piper holtonii as an Inhibitor of the Symbiotic Fungus Leucoagaricus gongylophorus of Leaf-Cutting Ants

Plants of the Piperaceae family are studied for their diverse secondary metabolism with a vast array of compounds that act as chemical defense agents against herbivores. Of all the agricultural pests, the management of insects is a highly significant challenge in the Neotropics, and ants of the Attini tribe pose a major problem. Due to their symbiotic association with the fungus Leucoagaricus gongylophorus (Möller) Singer (Agaricaceae), the species of Atta and Acromyrmex have exhaustive foraging activity which has intensified as deforestation and monoculture farming have increased. The control of leaf-cutting ants is still carried out with synthetic products with negative consequences to the environment and human health. In search for natural and sustainable alternatives to synthetic pesticides, Piper holtonii C. DC. was selected among other plant species after field observations of the foraging activity of Atta cephalotes, which revealed that P. holtonii was never chosen by ants. In vitro evaluation of an ethanol extract of the leaves of P. holtonii resulted in promising inhibitory activity (IC₅₀ 102 ppm) against L. gongylophorus. Subsequently, bioassay-guided fractionation led to the isolation of the phenylpropanoid dillapiole, which was also detected in the essential oil. This compound demonstrated inhibition of the fungus with an IC₅₀ of 38 ppm. Considering the symbiotic relationship between the Attini ants and L. gongylophorus, the negative effect on the survival of one of the organisms will affect the survival of the other, so dillapiole or standardized essential oil extracts of P. holtonii containing this active principle could be a unique and useful source as a control agent for leaf cutting-ants.

Piper Species: A Comprehensive Review on Their Phytochemistry, Biological Activities and Applications

Piper species are aromatic plants used as spices in the kitchen, but their secondary metabolites have also shown biological effects on human health. These plants are rich in essential oils, which can be found in their fruits, seeds, leaves, branches, roots and stems. Some Piper species have simple chemical profiles, while others, such as Piper nigrum, Piper betle, and Piper auritum, contain very diverse suites of secondary metabolites. In traditional medicine, Piper species have been used worldwide to treat several diseases such as urological problems, skin, liver and stomach ailments, for wound healing, and as antipyretic and anti-inflammatory agents. In addition, Piper species could be used as natural antioxidants and antimicrobial agents in food preservation. The phytochemicals and essential oils of Piper species have shown strong antioxidant activity, in comparison with synthetic antioxidants, and demonstrated antibacterial and antifungal activities against human pathogens. Moreover, Piper species possess therapeutic and preventive potential against several chronic disorders. Among the functional properties of Piper plants/extracts/active components the antiproliferative, anti-inflammatory, and neuropharmacological activities of the extracts and extract-derived bioactive constituents are thought to be key effects for the protection against chronic conditions, based on preclinical in vitro and in vivo studies, besides clinical studies. Habitats and cultivation of Piper species are also covered in this review. In this current work, available literature of chemical constituents of the essential oils Piper plants, their use in traditional medicine, their applications as a food preservative, their antiparasitic activities and other important biological activities are reviewed.

A systematic review on black pepper (Piper nigrum L.): from folk uses to pharmacological applications

Considered as the "King of spices", black pepper (Piper nigrum L.) is a widely used spice which adds flavor of its own to dishes, and also enhances the taste of other ingredients. Piper nigrum has also been extensively explored for its biological properties and its bioactive phyto-compounds. There is, however, no updated compilation of these available data to provide a complete profile of the medicinal aspects of P. nigrum. This study endeavors to systematically review scientific data on the traditional uses, phytochemical composition, and pharmacological properties of P. nigrum. Information was obtained using a combination of keywords via recognized electronic databases (e.g., Science Direct and Google Scholar). Google search was also used. Books and online materials were also considered, and the literature search was restricted to the English language. The country with the highest number of traditional reports of P. nigrum for both human and veterinary medicine was India, mostly for menstrual and ear-nose-throat disorders in human and gastrointestinal disorders in livestock. The seeds and fruits were mostly used, and the preferred mode of preparation was in powdered form, pills or tablets, and paste. Piper nigrum and its bioactive compounds were also found to possess important pharmacological properties. Antimicrobial activity was recorded against a wide range of pathogens via inhibition of biofilm, bacterial efflux pumps, bacterial swarming, and swimming motilities. Studies also reported its antioxidant effects against a series of reactive oxygen and nitrogen species including the scavenging of superoxide anion, hydrogen peroxide, nitric oxide, DPPH, ABTS, and reducing effect against ferric and molybdenum (VI). Improvement of antioxidant enzymes in vivo has also been reported. Piper nigrum also exhibited anticancer effect against a number of cell lines from breast, colon, cervical, and prostate through different mechanisms including cytotoxicity, apoptosis, autophagy, and interference with signaling pathways. Its antidiabetic property has also been confirmed in vivo as well as hypolipidemic activity as evidenced by decrease in the level of cholesterol, triglycerides, and low-density lipoprotein and increase in high-density lipoprotein. Piper nigrum also has anti-inflammatory, analgesic, anticonvulsant, and neuroprotective effects. The major bioactive compound identified in P. nigrum is piperine although other compounds are also present including piperic acid, piperlonguminine, pellitorine, piperolein B, piperamide, piperettine, and (-)-kusunokinin, which also showed biological potency. Most pharmacological studies were conducted in vitro (n = 60) while only 21 in vivo and 1 clinical trial were performed. Hence, more in vivo experiments using a pharmacokinetic and pharmacokinetic approach would be beneficial. As a conclusive remark, P. nigrum should not only be regarded as "King of spices" but can also be considered as part of the kingdom of medicinal agents, comprising a panoply of bioactive compounds with potential nutraceutical and pharmaceutical applications.

Effects of Essential Oils from Two Species of Piperaceae on Parasitized and Unparasitized Eggs ofOebalus insularis(Heteroptera: Pentatomidae) byTelenomus podisi(Hymenoptera: Platygastridae)

Biological control of Oebalus insularis eggs is considered an important strategy in the control of this rice “stink bug”. Effects of essential oils (EOs) from Piper jacquemontianum Kunth and Piper marginatum Jacq. (Piperaceae) on the viability of parasitized and unparasitized eggs by Telenomus podisi, in concentrations of 0.5 to 2.0%, were evaluated. EOs from both species at a concentration of 2% affected the development of embryons of O. insularis as well as of T. podisi after 24 and 48h of their administration. In both species, P. jacquemontanium and P. marginatum LC50, 24 h before the application of treatments on eggs of O. insularis was 3.835 y 3.037, respectively. LC50after 48 h of treatment with EOs showed contrasting results which varied from 2.207 and 1.811. for P. jacquemontianum and P. marginatum, respectively. LC50calculated before 24 h in parasitized eggs of O. insularis by T. podisi, was 3.037 and 2.171 for P. jacquemontianum y P. marginatum, respectively, while after 48h of treatment it was 1.166 y 1.935, respectively. Absorption of the EO components by the unparasitized and parasitized eggs of O. insularis by T. podisi was higher after 48 h of exposition. This is due to the longer exposure time, which allows higher penetration of the EOs into the interior of insect eggs by microscopic pores and micropyle.