Naturally-occurring Compounds Research Articles

Anticholinergic drugs for parkinsonism and other movement disorders.

Anticholinergic (AC) drugs, a medication class that acts by blocking nicotinic and muscarinic acetylcholine receptors, were first utilized for therapeutic purposes in the mid-19th century. Initial applications were as symptomatic therapy for Parkinson disease (PD), a practice continuing to the present. Initially, the AC drugs used were naturally-occurring plant compounds. Synthetic AC drugs were developed in the late 1940s and predominated in neurological therapeutics. Until the advent of pharmaceuticals acting upon striatal dopaminergic motor pathways, AC drugs provided the only effective means for lessening tremors and other clinical problems of the PD patient. However, because dopaminergic compounds are so effective at meeting the needs of the typical PD patient, AC medications are far less utilized by clinicians today. In recent years, there has been only a few investigations of AC drugs as neurological treatments. This review will revisit the clinical landscape of AC pharmacology and application for movement disorders along with recent research in search of improving therapeutics with AC drugs.

Phyllanthus-derived Naturally-occurring Products: An Overview of their Effects against Viruses in Cell Models

Background: Infectious diseases are considered a global public health problem, with viruses being the predominant infectious agents afflicting the human population. The most used control alternatives are the search and development of vaccines and drugs. Nevertheless, their efficacy has limitations related to the immune response stimulation, resistance mechanisms, costeffort ratio, development, and production. An alternative to these drawbacks is the search for compounds isolated from plants with antiviral and/or virucidal properties. The genus Phyllanthus is a plant group producing compounds that gathers an antiviral and virucidal spectrum on different biological models. However, there is no complete review of their properties against viruses in cell models. Objective: To compile and analyse the more relevant information on the antiviral and virucidal activity in cell models, phytochemical composition, and generalities of the genus Phyllanthus. Method: The information was assembled from a general search for articles in various databanks, and the information was organized, tabulated, and discussed. Results: The taxonomic classification of the genus Phyllanthus showed discrepancies between different authors and publications. The antiviral and virucidal effects of Phyllanthus naturallyoccurring compounds on cell models showed a broad spectrum and a high chemical diversity mainly related to phenols and polyphenols. Conclusion: Antiviral and virucidal properties of Phyllanthus-derived compounds showed promising results as controlling agents against viral infections in different cell models, particularly in the viral replication and translation processes. Further studies are required to elucidate the specific mechanisms involved in these natural alternatives to expand their efficient and effective applications.

Fluorescent properties of chitosan-stabilized bisdemethoxycurcumin-silver nanoparticles: Synthesis and characterization

The extraction and modification of naturally-occurring compounds are widely performed due to their valuable medicinal and physical properties. Herin, we reported the extraction of bis-demethoxycurcumin from Ragbrai turmeric root. The isolated derivative was characterized by X-ray diffraction, IR, and NMR spectroscopy. Also, the green synthesis of bis-demethoxycurcumin chitosan silver BDMC-Ag-Ch nanoparticles is illustrated. These nanoparticles are identified by atomic force microscopy AFM and exhibit average particle size ∼ 53.41 nm The crystalline structure was confirmed by XRD analysis, which showed distinct peaks corresponding to silver oxide nanoparticles and Zeta power measurements revealed stable dispersion of the nanoparticles, indicating a good chitosan coating on the surface of bis-demethoxycurcumin Ag nanoparticles. The absorption bands at 240 and 405 nm are due to oxygen atom (n → π*) and aromatic (π → π*) transitions in curcumin and Chitosan molecules. The photoluminescence (PL) study of synthesized BDMC-Ag-Ch nanoparticles demonstrated an existence of two emission excited states in light-emitting, namely local excited (LE) and intramolecular charge transfer (ICT) emission states, due to the aromatic conjugation system within BDMC units and intra charge transfer between the silver ion and organic part.

Nutritional and Medicinal Contribution of Wild Fruit Plants in Ethiopia

Wild fruit plants are used by rural populations around the world, including Ethiopia, as supplemental foods to improve dietary diversity. Because wild fruits are inexpensive and widely accessible in rural regions, they can help prevent hunger or malnutrition and ensure food diversity. This review aims to give a summary of the most recent research on the nutritional value and potential medical benefits of wild fruits for rural households. Antioxidant-rich naturally-occurring compounds found in wild fruits help to reduce non-communicable diseases. These days, non-communicable diseases like cancer, chronic respiratory conditions, obesity, diabetes, and cardiovascular diseases are the world’s biggest health problems. These plants, which are grown widely throughout nearly all of Ethiopia, offer a number of health and nutritional benefits. Many ethnic groups use these fruits as a seasonal or emergency food source, which helps to reduce food insecurity.

A Review on the Mechanism and Structure-activity Relationship of Resveratrol Heteroaryl Analogues.

Resveratrol is one of the most interesting naturally-occurring nonflavonoid phenolic compounds with various biological activities, such as anticancer, neuroprotection, antibacterial, and anti-inflammatory. However, there is no clinical usage of resveratrol due to either its poor activity or poor pharmacokinetic properties. Heteroarenes-modified resveratrol is one pathway to improve its biological activities and bioavailability, and form more modification sites. In this review, we present the progress of heteroaryl analogues of resveratrol with promising biological activities in the latest five years, ranging from the synthesis to the structure-activity relationship and mechanism of actions. Finally, introducing heteroarenes into resveratrol is an effective strategy, which focuses on the selectivity of structure-activity relationship in vivo.

Indole-containing pharmaceuticals: targets, pharmacological activities, and SAR studies.

Indole is a prestigious heterocyclic skeleton widely found in both naturally-occurring and biologically-active compounds. Pharmaceutical agents containing an indole skeleton in their framework possess a wide range of pharmacological properties, including antiviral, antitumor, analgesic, and other therapeutic activities, and many indole-containing drugs have been proven to have excellent pharmacokinetic and pharmacological effects. Over the past few decades, the FDA has approved over 40 indole-containing drugs for the treatment of various clinical conditions, and the development of indole-related drugs has attracted significant attention from medicinal chemists. This review aims to provide an overview of all the approved drugs that contain an indole nucleus, focusing on their targets, pharmacological activities, and SAR studies.

Plumbagin, a Natural Compound with Several Biological Effects and Anti-Inflammatory Properties.

Phytochemicals from various medicinal plants are well known for their antioxidant properties and anti-cancer effects. Many of these bioactive compounds or natural products have demonstrated effects against inflammation, while some showed a role that is only approximately described as anti-inflammatory. In particular, naphthoquinones are naturally-occurring compounds with different pharmacological activities and allow easy scaffold modification for drug design approaches. Among this class of compounds, Plumbagin, a plant-derived product, has shown interesting counteracting effects in many inflammation models. However, scientific knowledge about the beneficial effect of Plumbagin should be comprehensively reported before candidating this natural molecule into a future drug against specific human diseases. In this review, the most relevant mechanisms in which Plumbagin plays a role in the process of inflammation were summarized. Other relevant bioactive effects were reviewed to provide a complete and compact scenario of Plumbagin's potential therapeutic significance.

Preventive and therapeutic use of herbal compounds against doxorubicin induced hepatotoxicity: a comprehensive review.

Doxorubicin (DOX) is associated with numerous acute and chronic dose-related toxicities including hepatotoxicity. This adverse reaction may limit the use of other chemotherapeutic agents with hepatic excretion, and so, its prevention is an important issue. The aim of this study was to conduct a comprehensive review of in vitro, in vivo and human studies regarding the protective effects of synthetic and naturally-occurring compounds against DOX-induced liver injury. The search was conducted in Embase, PubMed, and Scopus databases using the following keywords: "doxorubicin," "Adriamycin," "hepatotoxicity," "liver injury," "liver damage," and "hepatoprotective," and all articles published in English were included without time restriction. Forty eligible studies to the end of May 2022 finally were reviewed. Our results demonstrated that all of these drugs, except acetylsalicylic acid, had considerable hepatoprotective effects against DOX. In addition, none of the studied compounds attenuated the antitumor efficacy of DOX treatment. Silymairn was the only compound which is assessed in human studies and showed promising preventive and therapeutic effects. Altogether, our results demonstrated that most of compounds with antioxidant, anti-apoptosis, and anti-inflammatory properties are efficacious against DOX-induced hepatotoxicity and may be considered as a potential adjuvant agent for prevention of hepatotoxicity in cancer patients, after fully been assessed in well-designed large clinical trials.

3-Methoxy Carbazole Impedes the Growth of Human Breast Cancer Cells by Suppressing NF-κB Signaling Pathway.

Breast cancer represents the most frequently occurring cancer globally among women. As per the recent report of the World Health Organization (WHO), it was documented that by the end of the year 2020, approximately 7.8 million females were positively diagnosed with breast cancer and in 2020 alone, 685,000 casualties were documented due to breast cancer. The use of standard chemotherapeutics includes the frontline treatment option for patients; however, the concomitant side effects represent a major obstacle for their usage. Carbazole alkaloids are one such group of naturally-occurring bioactive compounds belonging to the Rutaceae family. Among the various carbazole alkaloids, 3-Methoxy carbazole or C13H11NO (MHC) is obtained from Clausena heptaphylla as well as from Clausena indica. In this study, MHC was investigated for its anti-breast cancer activity based on molecular interactions with specific proteins related to breast cancer, where the MHC had predicted binding affinities for NF-κB with −8.3 kcal/mol. Furthermore, to evaluate the biological activity of MHC, we studied its in vitro cytotoxic effects on MCF-7 cells. This alkaloid showed significant inhibitory effects and induced apoptosis, as evidenced by enhanced caspase activities and the cellular generation of ROS. It was observed that a treatment with MHC inhibited the gene expression of NF-kB in MCF-7 breast cancer cells. These results suggest that MHC could be a promising medical plant for breast cancer treatment. Further studies are needed to understand the molecular mechanisms behind the anticancer action of MHC.

Influence of acid-base equilibria on the rate of the chemical reaction in the advanced oxidation processes: Coumarin derivatives and hydroxyl radical

The decomposition and chemical manipulation of stable aromatic pollutants into less toxic products is an important topic for wastewater management and natural water remediation. The mechanism of the Advanced Oxidation Process (AOPs) of 4,7-dihydroxycoumarin (4,7-DHC) and 7-hydroxycoumarin (7-HC), as examples of stable naturally-occurring industrially-important compounds, in the presence of hydroxyl radical (HO) in the aqueous solution has been analyzed using Electron Paramagnetic Resonance spectroscopy (EPR) and Quantum Mechanics-based test for Overall Free Radical Scavenging Activity (QM-ORSA). The effect of pH values of the medium on the investigated reaction mechanisms has been fully investigated. The rate constants were estimated by the conventional transition state theory (TST) and Eckart's method (ZCT_0). Estimated values of the overall rate constant (koverall) higher than >4.06 × 109 M−1 s−1 at all pH values showed that both compounds undergo a chemical transformation when exposed to HO. When pH increased in the range of 0–14, the koverall increased from 4.06 × 109 to 1.11 × 1010 (4.7-DHC) and 2.09 × 109 to 1.76 × 1010 M−1s−1 (7-HC). At physiological pH = 7.4 value, 7-HC was ∼1.5 times more prone to radical action, as shown by EPR and QM-ORSA, due to the dominant anionic form. Both compounds were more reactive towards HO than Trolox at this pH value. The ecotoxicity assessment of the starting compounds, intermediates and oxidation products indicated that the formed products show lower acute and chronic toxicity effects on aquatic organisms than starting compounds, which is a prerequisite for the development of novel AOPs procedures.

Gathering scientific evidence for a new bioactive natural ingredient: The combination between chemical profiles and biological activities of Flueggea virosa extracts

Flueggea virosa (Roxb. ex Willd.) Royle is a plant with several traditional uses in tropical countries. To study the potential usefulness, extracts from stem barks and leaves of F. virosa were obtained with different solvents. The phytochemical composition was assessed using LC-MS and NMR. Triterpenes, as oleanolic (0.05–88.09 mg/g extract), and ursolic (0.03–94.36 mg/g extract) acids were determined. In addition, ellagic and gallic acid derivatives were present in large concentrations in some of the extracts. Antioxidant (radical scavenging, reduction ability, and metal chelating) and enzyme inhibitory (cholinesterase, tyrosinase, amylase, and glucosidase) effects were assessed by in vitro chemical assays. The methanol extracts and infusions from both parts show higher antioxidant ability when compared with ethyl acetate extracts, and the antioxidant capacity was correlated with the total phenolic contents of the tested extracts. The extracts demonstrate enzyme inhibitory abilities on AChE and BChE, and multivariate approaches allowed for correlating the activities with the presence of triterpenoids (R > 0.8). Furthermore, molecular docking was used to get insights into the interactions between the triterpenoids and the tested enzymes. Together, these results indicate that F. virosa represents a significant source of naturally-occurring bioactive compounds that can be exploited as a new ingredient for the development of novel functional products with promising biological properties.

Dietary Flavonoids as Modulators of Lipid Metabolism in Poultry

Flavonoids, naturally-occurring compounds with multiple phenolic structures, are the most widely distributed phytochemicals in the plant kingdom, and are mainly found in vegetables, fruits, grains, roots, herbs, and tea and red wine products. Flavonoids have health-promoting effects and are indispensable compounds in nutritional and pharmaceutical (i.e., nutraceutical) applications. Among the demonstrated bioactive effects of flavonoids are anti-oxidant, anti-inflammatory, and anti-microbial in a range of research models. Through dietary formulation strategies, numerous flavonoids provide the ability to support bird health while improving the nutritional quality of poultry meat and eggs by changing the profile of fatty acids and reducing cholesterol content. A number of such compounds have been shown to inhibit adipogenesis, and promote lipolysis and apoptosis in adipose tissue cells, and thereby have the potential to affect fat accretion in poultry at various ages and stages of production. Antioxidant and anti-inflammatory properties contribute to animal health by preventing free radical damage in tissues and ameliorating inflammation in adipose tissue, which are concerns in broiler breeders and laying hens. In this review, we summarize the progress in understanding the effects of dietary flavonoids on lipid metabolism and fat deposition in poultry, and discuss the associated physiological mechanisms.

Curcumin-mediated photodynamic antimicrobial chemotherapy (PACT): a systematic review / Quimioterapia fotodinâmica antimicrobiana (PACT) mediada por curcumina: uma revisão sistemática

Light energy is known to be used to combat microbial growth. Photodynamic antimicrobial chemotherapy (PACT) has the potential to use different naturally-occurring compounds, such as photosensitizers. Curcumin is an example of a molecule of interest in different areas under different optics. This systematic review surveys the aims and scope of research on curcumin-mediated PACT published between January 2011 and December 2020. The search was carried out in MEDLINE, PubMed, EMBASE and Periódicos CAPES databases employing the keywords “Photodynamic antimicrobial chemotherapy”, “photosensitizer”, “curcumin” and the descriptor “Light-Emitting Diode”. It was observed that in the last decade little material meeting these criteria was published. Brazilian institutions concentrated most of their studies on cytotoxic activity. The most recent work, however, focused on antibiofilm activity. Gram-positive bacteria are more sensitive to curcumin-mediated PACT over a short wavelength range. Different concentrations and exposure time of the photosensitizer were evaluated, but the amount of information is still insufficient to establish the best treatment condition as the number of tested pathogens is still poor.

Aesculetin Accelerates Osteoblast Differentiation and Matrix-Vesicle-Mediated Mineralization.

The imbalance between bone resorption and bone formation in favor of resorption results in bone loss and deterioration of bone architecture. Osteoblast differentiation is a sequential event accompanying biogenesis of matrix vesicles and mineralization of collagen matrix with hydroxyapatite crystals. Considerable efforts have been made in developing naturally-occurring plant compounds, preventing bone pathologies, or enhancing bone regeneration. Coumarin aesculetin inhibits osteoporosis through hampering the ruffled border formation of mature osteoclasts. However, little is known regarding the effects of aesculetin on the impairment of matrix vesicle biogenesis. MC3T3-E1 cells were cultured in differentiation media with 1–10 μM aesculetin for up to 21 days. Aesculetin boosted the bone morphogenetic protein-2 expression, and alkaline phosphatase activation of differentiating MC3T3-E1 cells. The presence of aesculetin strengthened the expression of collagen type 1 and osteoprotegerin and transcription of Runt-related transcription factor 2 in differentiating osteoblasts for 9 days. When ≥1–5 μM aesculetin was added to differentiating cells for 15–18 days, the induction of non-collagenous proteins of bone sialoprotein II, osteopontin, osteocalcin, and osteonectin was markedly enhanced, facilitating the formation of hydroxyapatite crystals and mineralized collagen matrix. The induction of annexin V and PHOSPHO 1 was further augmented in ≥5 μM aesculetin-treated differentiating osteoblasts for 21 days. In addition, the levels of tissue-nonspecific alkaline phosphatase and collagen type 1 were further enhanced within the extracellular space and on matrix vesicles of mature osteoblasts treated with aesculetin, indicating matrix vesicle-mediated bone mineralization. Finally, aesculetin markedly accelerated the production of thrombospondin-1 and tenascin C in mature osteoblasts, leading to their adhesion to preformed collagen matrix. Therefore, aesculetin enhanced osteoblast differentiation, and matrix vesicle biogenesis and mineralization. These findings suggest that aesculetin may be a potential osteo-inductive agent preventing bone pathologies or enhancing bone regeneration.

Asaronic acid inhibits ER stress sensors and boosts functionality of ubiquitin-proteasomal degradation in 7β-hydroxycholesterol-loaded macrophages

BackgroundMisfolded proteins are formed in the endoplasmic reticulum (ER) due to diverse stimuli including oxidant production, calcium disturbance, and inflammatory factors. Accumulation of these non-native proteins in the ER evokes cellular stress involving the activation of unfolded protein response (UPR) and the execution of ER-associated degradation (ERAD). Naturally-occurring plant compounds are known to interfere with UPR due to their antioxidant and anti-inflammatory activities, leading to inhibition of ER stress. However, there are few studies dealing with the protective effects of natural compounds on the functionality of ERAD. PurposeThe current study examined whether asaronic acid enhanced ubiquitin-proteasomal degradation in J774A.1 murine macrophages exposed to 7β-hydroxycholesterol, a risk factor for atherosclerosis. Asaronic acid (2,4,5-trimethoxybenzoic acid), identified as one of purple perilla constituents, has anti-diabetic and anti-inflammatory effects. Little is known regarding the effects of asaronic acid on the ERAD process and the ubiquitin-proteasomal degradation. Methods and resultsMurine macrophages were incubated with 28 μM 7β-hydroxycholesterol in absence and presence of 1–20 μΜ asaronic acid for up to 24 h. Nontoxic asaronic acid in macrophage diminished the activation of the ER stress sensors of ATF6, IRE1 and PERK stimulated by 7β-hydroxycholesterol. This methoxybenzoic acid down-regulated the oxysterol-induced expression of EDEM1, OS9, Sel1L-Hrd1 and p97/VCP1, all required for the recognition, recruitment and dislocation of misfolded proteins. On the other hand, asaronic acid enhanced the ubiquitin-proteasomal degradation of non-native proteins dislocated to the cytosol by 7β-hydroxycholesterol, which entailed the induction of the chaperones of Hsp70 and CHIP and the increased colocalization of ubiquitin and proteasomes. Taken together, asaronic acid attenuated the induction of the UPR-associated sensors and the dislocation-linked transmembrane components in the ER. Conversely, this compound enhanced the proteasomal degradation of dislocated non-native proteins in concert with the chaperones of Hsp70 and CHIP through ubiquitination. ConclusionThese observations demonstrate that asaronic acid may be a potent atheroprotective agent as a natural chaperone targeting ER stress-associated macrophage injury.

Natural antimicrobial-coated supports as filter aids for the microbiological stabilisation of drinks

The strategy of applying surface modifications to inert supports to improve their physicochemical, biological and functional properties can be adopted to develop novel filtering materials by modifying surfaces of widely used materials with biocompatible antimicrobial molecules. This approach would enable overcoming the limitations of conventional filtration methodologies in water treatment and the microbial stabilisation of drinks. The covalent immobilisation of naturally-occurring antimicrobial compounds on filter surfaces allows the antimicrobial effectiveness of the anchored molecule to be preserved by conferring the support material antimicrobial and antifouling properties. This review focuses on describing the naturally-occurring antimicrobials used in the food industry to either prevent growth or inhibit microorganisms, and defines the most established immobilisation methodologies by reviewing the different materials that can be used as grafting supports, and providing details of some examples of naturally-occurring antimicrobial compounds immobilised on filter aids applied to microbiologically stabilise beverages. Besides overviewing the most recent research, this work discusses the advantages, limitations and challenges of developing natural antimicrobial-coated filter aids, and it points out the innovation potential beyond current research on different supports and applications. Before such aids are applied to a real environment, more knowledge on safety and manufacturing is needed on the industrial scale. Therefore, the information in this review may be valuable to extend new emerging preservation technologies to control the food and drink microbial contamination that results in minimally processed products.

Bioconversion of Shrimp Shell Waste into Compost Preparation and its Plant Growth Study

Background: The fishing sector plays an important role in the global economy. The development of this sector is related to environmental issues, in particular to waste management. Indeed, the quantity of the halieutic waste are considered at several thousand tons of waste a year. Waste management is a solution to maintain an area with ecological harmony, but still can produce economic benefits that are beneficial to social welfare. Chitinases are enzymes that degrade chitin. Chitinase contribute to the generation of carbon and nitrogen in the ecosystem from shrimp shell wastes. Chitin and chitosan are naturally-occurring compounds that have potential to be used in agriculture. The present study was designed to prepare the shrimp shell waste compost (SSC) and also to analyse the enhancement growth of Ladies finger plant by using shrimp shell waste compost (SSC), shrimp shell waste compost (SSC) +cow dung (CD) and along with coir pith (CP). Methods: This experiment was conducted within the period of 2017-2018 in Department of Microbiology, Kamaraj college, Thoothukudi. 1Kg of dried shrimp shell waste powder was used for the compost preparation using chitinolytic bacteria Bacillus licheniformis SSCL10. The present study shrimp shell wastes were composted into manure with adding chitinolytic Bacillus licheniformis SSCL10. After 90 days of composting, the compost was dried at room temperature and used as manure for plant study. The growth study of ladies finger (Abelmoschus esculents L.) was analyzed in shrimp shell compost and also along with other composts (SSC + CD and SSC + CD+CP). Result: In our study, nitrogen, phosphorus and potash content were increased in the shrimp shell composts (SSC) with adding chitinase producing bacterium (Bacillus licheniformis SSCL10) when compared with control soil. The maximum plant growth performances were showed in the SSC+CD (cow dung) compared to combination of CP (coir pith), shrimp shell composts (SSC) alone and control. So shrimp shell compost is used as supplements for other compost to induce plant growth performances.

ANTI-COAGULANT PROPERTIES OF FLAVONOID COMPOUNDS: POTENTIAL STRUCTURE-FUNCTIONAL RELATIONSHIP

Objective: Flavonoids, naturally-occurring compounds in fruits and vegetables, possess anti-coagulant property. However, a very few studies wereattempted to understand how flavonoid structure influences its anti-coagulation property, such as clotting time. In this study, we investigatedstructurally similar flavonoid compounds which differ in the number of hydroxyl groups and compared their anti-coagulation properties.Methods: We selected and evaluated five flavonoid compounds, that is, chrysin, apigenin, luteolin, kaempferol, and quercetin, for their anti-coagulantproperties using in vitro prothrombin time (PT) assays and activated partial thromboplastin time (APTT) assay.Results: Our findings suggested that quercetin, kaempferol, and luteolin showed a significant anti-coagulant effect on APTT (p<0.05) in a dosedependentmanner. The dose of 500 μM quercetin showed potent prolong APTT with 37.43±1.60 s, followed by 500 μM of kaempferol and luteolin(34.63±1.29 s and 4.83±1.56 s, respectively). Furthermore, a combination of 500 μM of quercetin with 0.25 U/ml of heparin demonstrated prolongAPTT (52.16±5.18 s) when compared with individual effects of either 0.25 U/ml heparin (33.4±0.50 s) or 500 μM quercetin (37.43±1.62 s) alone.Conclusion: Our results demonstrated that numbers of the hydroxyl group on flavonoid compounds influence anti-coagulation properties. Inaddition, the prolonged APTT assay results suggested that quercetin, kaempferol, and luteolin could affect factors VIII, IX, XI, and XII of intrinsicpathway. Moreover, the synergistic effect of quercetin further enhances the heparin anti-coagulation effect. Based on our findings, we recommendthat the consumption of vegetables and fruits rich in quercetin, luteolin, and kaempferol could help prevent thrombotic stroke in high-risk patients.

Synthesis and anti-tumor activity of 2-[(5-arylfuran-2-ylmethylene)-hydrazone]-thiazolidine-4-one

The thiazolidin-4-ones are an important class of attractive compounds. They exhibit a wide range of pharmacological activity. 4-Thiazolidone motif is considered as privileged scaffolds in medicinal chemistry and are is currently the subject of extensive research. No less interesting is the search for novels biologically activity compounds among the derivatives of furane. It is widely found in diverse pharmacologically active substances and naturally-occurring compounds. Among furane derivatives arylfuranes play also imported role in drug design and discovery. The objective of the present work was to synthesize a series of novel 2-[(5-arylfuran-2-ylmethylene)-hydrazone]-thiazolidine-4-ones. The corresponding thiosemicarbazones were synthesized by the interaction of 5-arylfuran-2-carbaldehydes with thiosemicarbazide. It was shown that they cyclocondensate with chloroacetic acid and ethyl 3-aryl-2-bromopropanate to form 2-[(5-aryl-2-ylmethylene) -hydrazono]-thiazolidin-4-ones. The structures of the obtained compounds were confirmed by 1H spectroscopy and elemental analysis. All these new compounds gave spectroscopic data in accordance with the proposed structures. Synthesized derivatives 6 a-b and 7 a-h were selected by National Cancer Institute (NCI, Bethesda USA) Developmental Therapeutic Program (DTP) and evaluated for anticancer activity at the concentration of 10 -5 M toward a panel of approximately sixty cancer cell lines (http://dtp.nci.nih.gov). The human tumor cell lines were derived from nine different cancer types: leukemia (CCRF-CEM, HL-60(TB), K-562, MOLT-4, RPMI-8226), melanoma (LOXIMVI, MALME-3M, M14, SK-MEL-2, SK-MEL-28, SK-MEL-5, UACC-257, UACC-62), lung (A549/ATCC, EKVX, HOP-62, HOP-92, NCI-H226, NCI-H23, NCI-H322M, NCI-H460, NCIH522), colon (COLO 205, HCT-116, HCT-15, HT29, KM12, SW-620), central nervous system (SF268, SF-295, SF-539, SNB-19, SNB-75, U251), ovarian (IGROV-1, OVCAR-3, OVCAR-4, OVCAR-5, SK-OV-3), renal (786-0, A498, ACHN, CAKI-1, RXF-393, SN12C, TK-10, UO-31), prostate (PC-3, Du-145) and breast cancers (MCF7, NCI/ADR-RES, MDA-MB-231/ATCC, HS 578T, MDA-MB-435, BT-549, T-47D). The results for each tested compound were reported as the growth percentage of the treated cells when compared to that of the untreated control cells. The test compounds show moderate antitumor activity. The UO-31 renal cancer line was sensitive to 2 -{[5- (4-Chlorophenyl) -furan-2-ylmethylene] -hydrazono} -5- (4-methoxybenzyl) -thiazolidin-4-one. Moderate HOP-92 activity in non-small cell lung cancer was also observed for most compounds. Keywords : organic synthesis, cyclocondensation, thiosemicarbazide, thiazolidin-4-one, furan.

Chemical Characterization and Antibacterial Efficacy of Essential Oils of Three Lamiaceae Species Growing in Cameroon

Essential oils (EOs) have aroused attention among the naturally-occurring therapeutic compounds with anti-infective properties. This study examined the chemical composition and the antibacterial potential of EOs from three Lamiaceae species including Ocimum gratissimum (leaves), Plecthrantus epilithicus (leaves), and Satureja robusta (leaves and flowers). EOs were obtained by hydrodistillation using a Clevenger-type apparatus, followed by characterization by gas chromatography-mass spectrometry (GC-MS) and flame ionization detector (GC/FID). The antibacterial efficacy of EOs was screened using the microdilution method, against a panel of eight foodborne bacteria isolates namely Enterobacter cloacae, Yersinia enterocolotica, Klebsiella pneumoniae, Salmonella typhi, Escherichia coli, Citrobacter freundii, Shigella flexneri, and Enterococcus faecalis. GC-MS and GC/FID analysis led to the identification of 53 components from EOs of P. epilithicus, while around forty compounds have been characterized from the EOs of O. gratissimum (43), leaves of Satureja robusta (43), and flowers of S. robusta (44). The nature of identified compounds varied according to the species. The most prevalent volatile compounds identified in the EOs of P. epilithicus were piperitenone oxide (23.65%) and two isomers piperitone oxide 2/2 (16.15%) and piperitone oxide 1/2 (7.24%). The major constituents in the EOs of leaves of O. gratissimum were elemicin (33.474%) and eugenol (30.258%). Piperitone oxide, piperitone, and germacrene D were identified as major constituents in both the EOs of leaves of S. robusta (28.3%, 15.14%, and 9.42% respectively) and flowers (45.6%, 11.55%, and 3.94% respectively). The oils displayed selective antibacterial potential, with the recorded minimal inhibitory concentration (MIC) values ranging from 0.0156 to 1% (v/v). EOs of P. epilithicus as well as that of the leaves and flowers of S. robusta acted against all studied bacteria. Most of the MIC values were below 0.25% (v/v), indicating a strong inhibitory potential of studied EOs. The present study provides a strong baseline for consideration of the EOs from O. gratissimum, S. robusta, and P. epilithicus in the control of bacterial foodborne infections.