Spectrum Of Biological Activities Research Articles

Prenylated Flavonoids Isolated from the Root of Sophora flavescens as Potent Antifungal Agents against Botrytis cinerea.

Sophora flavescens, a traditional Chinese herb, produces a wide range of secondary metabolites with a broad spectrum of biological activities. In this study, we isolated six isopentenyl flavonoids (1-6) from the roots of S. flavescens and evaluated their activities against phytopathogenic fungi. In vitro activities showed that kurarinone and sophoraflavanone G displayed broad spectrum and superior activities, among which sophoraflavanone G displayed excellent activity against tested fungi, with EC50 values ranging from 4.76 to 13.94 μg/mL. Notably, kurarinone was easily purified and showed potential activity against Rhizoctonia solani, Botrytis cinerea, and Fusarium graminearum with EC50 values of 16.12, 16.55, and 16.99 μg/mL, respectively. Consequently, we initially investigated the mechanism of kurarinone against B. cinerea. It was found that kurarinone disrupted cell wall components, impaired cell membrane integrity, increased cell membrane permeability, and affected cellular energy metabolism, thereby exerting its effect against B. cinerea. Therefore, kurarinone is expected to be a potential candidate for the development of plant fungicides.

Naturally Occurring Xanthones and Their Biological Implications.

Xanthones are chemical substances in higher plants, marine organisms, and lower microorganisms. The most prevalent naturally occurring sources of xanthones are those belonging to the families Caryophyllaceae, Guttiferae, and Gentianaceae. Structurally, xanthones (9H xanthan-9-one) are heterocyclic compounds with oxygen and a γ-pyrone component. They are densely packed with a two-benzene ring structure. The carbons in xanthones are numbered from their nucleus and biosynthetic construct. They have mixed shikimate-acetate (higher plants) and acetate-malonate (lower organisms) biosynthetic origins, which influence their classification. Based on the level of oxidation of the C-ring, they are classified into monomers, dimers, and heterodimers. While based on the level of oxygenation or the type of ring residue, they can be categorized into mono-, di-, tri-, tetra-, penta- and hexa-oxygenated xanthones, bis-xanthones, prenylated and related xanthones, xanthonolignoids, and other miscellaneous xanthones. This structural diversity has made xanthones exhibit considerable biological properties as promising antioxidant, antifungal, antimicrobial, and anticancer agents. Structure-activity relationship studies suggest C-1, C-3, C-6, and C-8 as the key positions that influence the biological activity of xanthones. Furthermore, the presence of functional groups, such as prenyl, hydroxyl, glycosyl, furan, and pyran, at the key positions of xanthones, may contribute to their spectrum of biological activity. The unique chemical scaffolds of xanthones, their notable biological activities, and the structure-activity relationships of some lead molecules were discussed to identify lead molecules as possible drug candidates.

Unveiling Drimenol: A Phytochemical with Multifaceted Bioactivities.

Drimenol, a phytochemical with a distinct odor is found in edible aromatic plants, such as Polygonum minus (known as kesum in Malaysia) and Drimys winteri. Recently, drimenol has received increasing attention owing to its diverse biological activities. This review offers the first extensive overview of drimenol, covering its sources, bioactivities, and derivatives. Notably, drimenol possesses a wide spectrum of biological activities, including antifungal, antibacterial, anti-insect, antiparasitic, cytotoxic, anticancer, and antioxidant effects. Moreover, some mechanisms of its activities, such as its antifungal effects against human mycoses and anticancer activities, have been investigated. However, there are still several crucial issues in the research on drimenol, such as the lack of experimental understanding of its pharmacokinetics, bioavailability, and toxicity. By synthesizing current research findings, this review aims to present a holistic understanding of drimenol, paving the way for future studies and its potential utilization in diverse fields.

“Thiophene”: A Sulphur Containing Heterocycle as a Privileged Scaffold

: In the rapidly expanding chemical realm of heterocyclic compounds with interesting therapeutic properties, the thiophene nucleus has established itself as a prospective entity. The biological activity of comparable substances produced via different pathways is of varying magnitudes. Medicinal chemists use their understanding of multiple synthetic pathways and the various physicochemical properties of such compounds to create a combinatorial library and conduct thorough searches for lead molecules. Due to their vast spectrum of biological actions, heterocyclic compounds play a crucial role in Medicinal chemistry and are extensively researched in the field of drug design and development. Thiophene, a sulfur- containing heterocyclic scaffold, has emerged as a rather well-explored scaffold for the synthesis of a library of molecules with biological functions, including antibacterial, antipsychotic, anticancer, analgesic, anti-inflammatory, anti-arrhythmic, and so on. Depending on the kind and position of substitution, thiophene analogues have been shown to bind to a wide spectrum of cancer-specific protein targets. As a result, thiophene analogues have been found to exert their biological effects by inhibiting various cancerrelated signalling pathways. The study of thiophene in Medicinal chemistry resulted in molecules that combine the thiophene moiety with traditional drug components in a single molecule. This review covers the biological and medical activity of compounds containing a thiophene nucleus, as well as information on thiophene behaviour, synthesis, and agents, with a focus on synthetic techniques, biological profiles, and structure-activity relationship (SAR) research.

Novel therapeutic agents for H5N1 influenza virus through 3D-QSAR, molecular docking, ADMET prediction, and DFT based global reactivity descriptors.

Avian influenza is a severe respiratory disease that can cause catastrophic outbreaks in domestic poultry and wild birds as well as significant risks to people. This has motivated many researchers to develop new, effective neuraminidase (NA) inhibitors to treat this serious infection. In this context, this study aims to develop new potential NA inhibitors using five computational methods. A three-dimensional quantitative structure-activity relationship (3D-QSAR) comparative molecular similarity indices analysis (CoMSIA) was performed on a set of N-substituted Oseltamivir derivatives as anti-influenza agents. As a result, the best CoMSIA model was robust and predictive (R2 = 0.966, Q2 = 0.772, and = 0.721). Based on the contour map analysis, 17 new NA inhibitors with high-predicted inhibitory activity were developed. Molecular docking was used to discover the binding modes and interactions between the 17 newly designed NA compounds and the corresponding NA protein. Based on the absorption, distribution, metabolism, elimination, and toxicity (ADMET) properties, the compounds C10, C11, C12, C15, C16, and C17 have good drug-likeness and pharmacokinetics properties and could be new promising anti-influenza drugs. The six leading compounds further went through biological activity spectra prediction and quantum method density functional theory (DFT) study, which confirmed the trends and the utility of 3D-QSAR CoMSIA and molecular docking in developing new NA inhibitors.

Urolithin A Ameliorates the TGF Beta-Dependent Impairment of Podocytes Exposed to High Glucose

Increased activity of transforming growth factor-beta (TGF-β) is a key factor mediating kidney impairment in diabetes. Glomerular podocytes, the crucial component of the renal filter, are a direct target of TGF-β action, resulting in irreversible cell loss and progression of chronic kidney disease (CKD). Urolithin A (UA) is a member of the family of polyphenol metabolites produced by gut microbiota from ellagitannins and ellagic acid-rich foods. The broad spectrum of biological activities of UA makes it a promising candidate for the treatment of podocyte disorders. In this in vitro study, we investigated whether UA influences the changes exerted in podocytes by TGF-β and high glucose. Following a 7-day incubation in normal (NG, 5.5 mM) or high (HG, 25 mM) glucose, the cells were treated with UA and/or TGF-β1 for 24 h. HG and TGF-β1, each independent and in concert reduced expression of nephrin, increased podocyte motility, and up-regulated expression of b3 integrin and fibronectin. These typical-for-epithelial-to-mesenchymal transition (EMT) effects were inhibited by UA in both HG and NG conditions. UA also reduced the typically elevated HG expression of TGF-β receptors and activation of the TGF-β signal transducer Smad2. Our results indicate that in podocytes cultured in conditions mimicking the diabetic milieu, UA inhibits and reverses changes underlying podocytopenia in diabetic kidneys. Hence, UA should be considered as a potential therapeutic agent in podocytopathies.

One-pot three-component synthesis of 2,4-dimethoxy-5,8,9,10-tetrahydropyrimido[4,5-b]quinolinone derivatives along with in silico and in vitro investigation of their antimalarial activity

Pyrimidoquinolinone-derived compounds have exhibited a broad spectrum of biological activities and have been acknowledged as a potential antimalarial scaffold through multiple conventional strategies. In the present study, a novel series of 2,4-dimethoxy-5,8,9,10-tetrahydropyrimido[4,5-b]quinolinones 4(a-m) were synthesized via a one-pot three-component reaction of cyclohexane-1,3‑dione, 4-amino-2,6-dimethoxypyrimidine and various aldehyde with l-proline as the catalyst and acetic acid as the solvent under reflux condition. In vitro antimalarial activity toward P. falciparum 3D7 strain cultures were investigated. Compounds 4b and 4m demonstrated significant efficacy against strains of P. falciparum, with IC50 values of 0.63 and 0.65 μg/mL, respectively. The results were also supported by molecular docking and ADME assays.

Phytochemical characterization, biochemical profiling and evaluation of anticancer potential of methanolic extract of Withania somnifera stem.

Phytotherapy employs phytoconstituents/phytomedicines derived from plants for treating and preventing illnesses. Withania somnifera is known in the Indian Ayurveda Pharmacopoeia for its medicinal applications and pharmacological properties. In this study, we examined the biological activity spectrum of Withania somnifera methanolic extract of stem (WSME), which is valued as a "Rasayana" due to its extensive range of medicinal uses. WSME was subjected to TPC and TFC quantification and bioactive components were characterized using LC-MS. Its antioxidant potential was gauged by DPPH and H2O2 radical scavenging assays, while antibacterial efficacy was assessed against S.aureus and E.coli using disc diffusion assay. In vitro anticancer activity was evaluated against human breast cancer MDA-MB-231 cells while toxicity was evaluated against normal Vero cells using MTT assay. WSME, rich in Withaferin A, showed TPC of 4.73±0.15 mg GAE/g and TFC of 94.94±6.15 mg QE/g dry weight of extract. It exhibited significant antioxidant activity (43.28 and 66.8 % inhibition at 1,000 μg/mL using DPPH and H2O2 assays, respectively) and mild antibacterial effects against S.aureus (300-500 mg/mL). WSME induced cell death in MDA-MB-231 cells and significantly inhibited their growth (IC50: 66 μg/mL, P value<0.05) without affecting normal Vero cells in the studied range of 25-400 μg/mL (IC50: 6.09 mg/mL, P value>0.05). The present study lends support to further testing of WSME against other cancer cell lines and animal models of cancer. These preclinical studies would provide further validation to its prospective use as an adjunct in human breast cancer therapy.

The Comparative Study of the Antioxidant and Antibacterial Effects of Propolis Extracts in Veterinary Medicine.

Antimicrobial resistance (AMR) is one of the biggest threats to human and animal health. Efforts to combat AMR include the introduction of antimicrobial drugs as alternative treatment options. To contribute to an effective plan for the treatment of infectious diseases caused by bacteria, the development of new antimicrobial agents is increasingly being explored. Propolis has garnered significant attention from both scientists and industry due to its extensive spectrum of biological activity. The growing interest in polyphenols of natural origin and their plant sources further encourages the investigation of their chemical composition and biological effects. Propolis serves as a rich source of phenolic compounds. Baltic region propolis, classified as poplar-type propolis, was selected for this study, and extracts were prepared using raw propolis materials from various Baltic countries. The production of liquid extracts utilized a combination of 70 percent ethanol, a mixture of water and poloxamer P407, and DES (deep eutectic solvent). The research aims to produce liquid propolis extracts using different solvents and to assess their chemical composition, antioxidant, and antimicrobial activity against different veterinary pathogens. Antioxidant activity was evaluated using DPPH (2,2-diphenyl-1-picrylhydrazyl), revealing antioxidant activity in all extracts, with results correlating with the total phenolic compound content. It was found that p-coumaric acid predominated in the studied propolis extracts (in ethanol extracts 1155.90-1506.65 mg/g, in DES extracts 321.13-954.76 mg/g, and in polymeric extracts 5.34-30.80 mg/g), with smaller amounts of ferulic acid and vanillin detected. Clinical and reference bacterial strains were collected from the Lithuanian University of Health Sciences, the Academy of Veterinary Medicine, and the Institute of Microbiology and Virology. To effectively treat bacterial infections, the antimicrobial activity of propolis extracts was tested against six pathogenic bacterial species and one pathogenic fungus (S. aureus, S. agalactiae, B. cereus, E. faecalis, E. coli, P. aeruginosa, and C. albicans). Antimicrobial activity studies demonstrated that DES propolis extracts exhibited stronger antimicrobial activity compared to ethanolic propolis extracts. The minimum inhibitory concentration (MIC) values of DES propolis extracts against the tested strains ranged between 50 and 1000 μg/mL. Considering the study results, it can be concluded that propolis from the Baltic region is abundant in phenolic compounds exhibiting antioxidant and antibacterial activities.

Synthesis and Cytotoxic Activity of Friedelinyl Esters.

Commonly isolated from plants of Celastraceae family, pentacyclic triterpenoids have a broad spectrum of biological activities, such as antitumor, anti-inflammatory, antinociceptive properties, among others. Structural modifications in these triterpenoids can enhance their biological activity, as well as their selectivity, while improving their physicochemical and pharmacokinetic aspects. In this study, eight novel esters were synthesized: four derivatives of 3α-friedelinol (friedelan-3α-yl p-bromobenzoate (1a); friedelan-3α-yl naproxenate (1b); friedelan-3α-yl pent-4-ynoate (1c); friedelan-3α-yl undec-10-ynoate (1d)) and four derivatives of 3β-friedelinol (friedelan-3β-yl p-bromobenzoate (2a); friedelan-3β-yl naproxenate (2b); friedelan-3β-yl pent-4-ynoate (2c); friedelan-3β-yl undec-10-ynoate (2d)). Overall, 3α-friedelinol showed greater reactivity when compared to the β-epimer. The esters 1b-d and 2b-c were tested for antileukemic activity against THP-1 and K-562 cells but showed low cytotoxicity for both cell lines. The most active against THP-1 cells was friedelan-3β-yl naproxenate (2b, IC50=266±6 μM), and the most active against K-562 cells was friedelan-3α-yl pent-4-ynoate (1c, IC50=267±5 μM).

Solid-phase synthesis of amphiphilic cyclic peptides as a surfactin mimetic

The cyclic lipopeptide surfactin, an anionic biosurfactant, has received increased interest owing to its unique characteristics and promising applications. Although surfactin is known to exhibit distinctive surface activities and self-assembly ability, the role of the cyclic peptide moiety in its physico-chemical properties requires further investigation. Here, we report the solid-phase peptide synthesis of surfactin mimics such as cyclic heptapeptides with the same amino acid sequence as surfactin (CSF) and cyclic octapeptides with dodecyl chains (CSF12). The structure–property relationships of the cyclic peptides were then examined. The acidic forms of CSF and CSF12 were poorly soluble in water, but the addition of 1.5 or 2.0 equiv. of NaOH increased their solubility in aqueous solutions. The disodium salt of CSF (CSF-2Na) reduced the surface tension of water to 39.0 mN/m despite its absence of a long alkyl chain, indicating that the cyclic peptide moiety plays a crucial role in the surface activity of the surfactin mimic. In the case of the disodium salt of CSF12 (CSF12–2Na), the introduction of a dodecyl chain to the cyclic peptide moiety led to an increase in molecular orientation such that saturation at the air–water interface was observed. Thus, a long alkyl chain enhances the molecular assembly of the cyclic peptide at the air–water interface. The introduction of a long alkyl chain also enhanced the solubilisation of phospholipids. For instance, CSF12–1.5Na induced the solubilisation of L-α-dimyristoylphosphatidylcholine (DMPC) multilamellar vesicles in phosphate-buffered saline (PBS). These findings greatly contribute to the fundamental understanding of the broad spectrum of physico-chemical properties and biological activities of bio-derived cyclic peptides. Furthermore, these insights can also be helping design libraries for developing cyclic peptides for challenging therapeutics in skin disease or as cosmeceuticals to enhance skin appearance.

Comparative Genomics Screens Identify a Novel Small Secretory Peptide, SlSolP12, which Activates Both Local and Systemic Immune Response in Tomatoes and Exhibits Broad-Spectrum Activity.

Small secreted peptides (SSPs) are essential for defense mechanisms in plant-microbe interactions, acting as danger-associated molecular patterns (DAMPs). Despite the first discovery of SSPs over three decades ago, only a limited number of SSP families, particularly within Solanaceae plants, have been identified due to inefficient approaches. This study employed comparative genomics screens with Solanaceae proteomes (tomato, tobacco, and pepper) to discover a novel SSP family, SolP. Bioinformatics analysis suggests that SolP may serve as an endogenous signal initiating the plant PTI response. Interestingly, SolP family members from tomato, tobacco, and pepper share an identical sequence (VTSNALALVNRFAD), named SlSolP12 (also referred to as NtSolP15 or CaSolP1). Biochemical and phenotypic analyses revealed that synthetic SlSolP12 peptide triggers multiple defense responses: ROS burst, MAPK activation, callose deposition, stomatal closure, and expression of immune defense genes. Furthermore, SlSolP12 enhances systemic resistance against Botrytis cinerea infection in tomato plants and interferes with classical peptides, flg22 and Systemin, which modulate the immune response. Remarkably, SolP12 activates ROS in diverse plant species, such as Arabidopsis thaliana, soybean, and rice, showing a broad spectrum of biological activities. This study provides valuable approaches for identifying endogenous SSPs and highlights SlSolP12 as a novel DAMP that could serve as a useful target for crop protection.

Attenuation of Quorum Sensing Mediated Virulence Factors and Biofilm Formation in Pseudomonas Aeruginosa PAO1 by Substituted Chalcones and Flavonols.

Flavonoids epitomize structural scaffolds in many biologically active synthetic and natural compounds. They showcase a diverse spectrum of biological activities including anticancer, antidiabetic, antituberculosis, antimalarial, and antibiofilm activities. The antibiofilm activity of a series of new chalcones and flavonols against clinically significant Pseudomonas aeruginosa PAO1 strain was studied. Antivirulence activities were screened by analysing the effect of compounds on the production of virulence factors like pyocyanin, LasA protease, cell surface hydrophobicity, and rhamnolipid. The best ligands towards the quorum sensing proteins LasR, RhlR, and PqsR were recognised using a molecular docking study. The gene expression in P. aeruginosa after treatment with test compounds was evaluated on quorum sensing genes including rhlA, lasB, and pqsE. The antibiofilm potential of chalcones and flavonols was confirmed by the efficient reduction in the production of virulence factors and downregulation of gene expression.

Identification of Secondary Metabolites by UHPLC-ESI-HRMS/MS in Antifungal Strain Trichoderma harzianum (LBAT-53).

Trichoderma spp. are filamentous fungi generally observed in nature, which are widely marketed as biocontrol agents. The secondary metabolites produced have obtained special attention since they possess attractive chemical structures with a broad spectrum of biological activities. In Cuba, the species of Trichoderma have been commercially applied for the control of several phytopathogens to protect agricultural crops, but few studies have been carried out to detect and characterize the production of metabolites with biological activity. The strain Trichoderma harzianum LBAT-53 was subjected to an antifungal in vitro assay against Fusarium oxysporum f.sp. cubense by dual culture and volatile metabolite assays and fermented in PDB under constant agitation conditions. The ethyl acetate crude extract was obtained by liquid-liquid extraction. The fungal extract was investigated for the composition of secondary metabolites through chemical screening and ultrahigh performance liquid chromatography-tandem mass spectrometry (UHPLC-MS/MS) in negative ionization mode. As a result, LBAT-53 showed antagonistic activity in vitro (Class 2) against the pathogen evaluated in direct confrontation (76.9% of inhibition in 10 days) and by volatile metabolites (<40% in 7 days). Furthermore, seven low-molecular-weight phenolic compounds, including chrysophanol, phomarin, endocrocin, and trichophenol A, among others, were identified using UHPLC-ESI-MS/MS. This study is the first work on the characterization of secondary metabolites produced by the commercially applied strain LBAT-53, which is a promising source of bioactive compounds. These results provide a better understanding of the metabolism of this fungus, which is widely used in Cuba as biopesticides in agriculture pest control.

An Outlook on Platinum-Based Active Ingredients for Dermatologic and Skincare Applications.

Platinum-based materials exhibit a broad spectrum of biological activities, including antioxidant, anti-inflammatory, antimicrobial, and pro-collagen synthesis properties, making them particularly useful for various biomedical applications. This review summarizes the biological effects and therapeutic potential of platinum-based active ingredients in dermatological and skincare applications. We discuss their synthesis methods and their antioxidant, anti-inflammatory, antimicrobial, and collagen synthesis properties, which play essential roles in treating skin conditions including psoriasis and acne, as well as enhancing skin aesthetics in anti-aging products. Safety and sustainability concerns, including the need for green synthesis and comprehensive toxicological assessments to ensure safe topical applications, are also discussed. By providing an up-to-date overview of current research, we aim to highlight both the potential and the current challenges of platinum-based active ingredients in advancing dermatology and skincare solutions.

28-Norlupanes and dammaranes from the heartwood of Dipterocarpus costatus Gaertn. f. (Dipterocarpaceae) and their cytotoxic and antiplasmodial activities

Triterpenoids of natural origin are of increasing interest due to their broad spectrum of biological activities. Previous studies on dipterocarpaceous plants have reported that they were valuable source of new active natural compounds. As part of an ongoing search for naturally occurring bioactive triterpenoids from Dipterocarpaceae, phytochemical investigation of Dipterocarpus costatus Gaertn. f. heartwood collected in Thailand was conducted. Seventeen triterpenoids (1-17) belonging to both 28-norlupane and dammarane series were isolated from the corresponding bioactive n-hexane extract. Among them, norlupane 1 was identified as previously undescribed and norlupane 2 was described for the first time from a natural source. Compound structures were elucidated by 1D/2D-NMR spectroscopy and mass (HRMS) spectrometry. All isolated molecules were tested for their cytotoxicity on two human colorectal carcinoma cell lines (i.e. HT-29 and HCT116), as well as for their antiplasmodial activity against chloroquine-resistant strain FcB1 of Plasmodium falciparum. Norlupanes 2 and 4 were shown to exhibit a good cytotoxic activity against HCT 116 (IC50=4.2 µM) and potent antiplasmodial activity (IC50=3.74 µM), respectively.

D-Hexopyranosides with Vicinal Nitrogen-Containing Functionalities.

Various substituted D-hexopypyranosides units with nitrogen-containing functionalities are present in many important natural compounds and pharmaceutical substances. Since their complex structural diversity contributes to a broad spectrum of biological functions and activities, these derivatives are frequently studied. This review covers syntheses of D-hexopyranosides with vicinal nitrogen-containing functionalities since the 1960s, when the first articles emerged. The syntheses are arranged according to the positions of substitutions, to form a relative configuration of vicinal functionalities, and synthetic methodologies.

Poplar Bud (Populus) Extraction and Chinese Propolis Counteract Oxidative Stress in Caenorhabditis elegans via Insulin/IGF-1 Signaling Pathway.

Poplar buds are characterized by a high content of phenolic compounds, which exhibit a broad spectrum of biological activities. However, the relationship between Chinese propolis and poplar buds based on their antioxidant capacities and underlying mechanisms remains unclear. This study aimed to investigate the antioxidant properties of poplar bud (Populus) extract (PBE) and Chinese propolis (CP) and to elucidate the mechanisms behind their activity. High-performance liquid chromatography (HPLC) analysis revealed that both PBE and CP contain a significant amount of phenolic acids and flavonoids. 2,2-diphenyl-1-picrylhydrazyl (DPPH), 2,2'-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid) (ABTS), and ferric-reducing antioxidant power (FRAP) assays demonstrated that PBE and CP possess excellent antioxidant activity. Furthermore, administration of PBE and CP improved the survival rate of C. elegans under oxidative stress. They also decreased the levels of reactive oxygen species (ROS) and malondialdehyde (MDA), while enhancing the activity of antioxidant enzymes (SOD, CAT). PBE and CP intervention upregulated the expression of key genes daf-16, sod-3, hsp-16.2, and skn-1 in nematodes. This suggests that the antioxidant activity of PBE and CP is dependent on daf-16 and skn-1 signaling pathways. In conclusion, poplar bud extracts ha have the potential to become a substitute for propolis and a potential therapeutic agent for treating diseases associated with oxidative damage.

Preliminary phytochemical and biological activity screening of Sargassum lapazeanum

Algae are exposed to substantial stress. In response, these organisms have developed efficient defense systems, such as protective secondary metabolite synthesis, making algae a primary source of bioactive compounds with a wide spectrum of biological activities. Thus, algae show potential for use in treatments of thrombotic, infectious, and chronic degenerative diseases. Therefore, the objective of this study was to evaluate the phytochemical compounds and pharmacological activity of an extract obtained from Sargassum lapazeanum. Algae were collected in the intertidal zone of Tarabillas beach (Bahía de La Paz, BCS). The biological activities of an ethanolic extract and its fractions were evaluated using chromatographic techniques. In addition, a bioautographic assay of hemolytic activity was conducted, and phytochemical profiles and acute toxicity in Artemia franciscana were evaluated. The relationships among the main extract components were also determined. The ethanolic extract exhibited significant antioxidant and hemolytic activity, which was mainly attributed to its content of anthrones, anthraquinones, and unsaturated triterpenes. Its toxicological activity reached an LC50 value of 225.1 μg mL-1, which was mainly attributed to alkaloids, flavonoids, anthrones, and saponins. The results suggest that Sargassum lapazeanum, which is endemic to the Gulf of California, has great pharmacological potential with biomedical applications.

Assessment of Antimicrobial and Cytotoxic Activities of Liposomes Loaded with Curcumin and Lippia origanoides Essential Oil.

(1) Introduction: Curcumin and Lippia origanoides essential oils have a broad spectrum of biological activities; however, their physicochemical instability, low solubility, and high volatility limit their therapeutic use. Encapsulation in liposomes has been reported as a feasible approach to increase the physicochemical stability of active substances, protect them from interactions with the environment, modulate their release, reduce their volatility, improve their bioactivity, and reduce their toxicity. To date, there are no reports on the co-encapsulation of curcumin and Lippia origanoides essential oils in liposomes. Therefore, the objective of this work is to prepare and physiochemical characterize liposomes loaded with the mixture of these compounds and to evaluate different in vitro biological activities. (2) Methods: Liposomes were produced using the thin-layer method and physiochemical characteristics were calculated. The antimicrobial and cytotoxic activities of both encapsulated and non-encapsulated compounds were evaluated. (3) Results: Empty and loaded nanometric-sized liposomes were obtained that are monodisperse and have a negative zeta potential. They inhibited the growth of Staphylococcus aureus and did not exhibit cytotoxic activity against mammalian cells. (4) Conclusions: Encapsulation in liposomes was demonstrated to be a promising strategy for natural compounds possessing antimicrobial activity.