Optimized carotenoid production and antioxidant capacity of Gordonia hongkongensis.

The current emphasis within the cosmetic market on sustainable ingredients has heightened the exploration of new sources for natural, active components. Actinomycetota, recognized for producing pigments with bioactive potential, offer promising functional cosmetic ingredients. This study aimed to optimize pigment and antioxidant metabolite production from the Gordonia hongkongensis strain EUFUS-Z928 by implementing the Plackett-Burman experimental design and response surface methodology. Extracts derived from this strain exhibited no cytotoxic activity against human primary dermal fibroblast (HDFa, ATCC® PCS-201-012™, Primary Dermal Fibroblast; Normal, Human, Adult). Eight variables, including inoculum concentration, carbon and nitrogen source concentration, NaCl concentration, pH, incubation time, temperature, and stirring speed, were analyzed using the Plackett-Burman experimental design. Subsequently, factors significantly influencing pigment and antioxidant metabolite production, such as temperature, inoculum concentration, and agitation speed, were further optimized using response surface methodology and Box-Behnken design. The results demonstrated a substantial increase in absorbance (from 0.091 to 0.32), DPPH radical scavenging capacity (from 27.60% to 84.61%), and ABTS radical scavenging capacity (from 17.39% to 79.77%) compared to responses obtained in the isolation medium. The validation of the mathematical model accuracy exceeded 90% for all cases. Furthermore, liquid chromatography coupled with mass spectrometry (LC-MS) facilitated the identification of compounds potentially responsible for enhanced pigment production and antioxidant capacity in extracts derived from G. hongkongensis. Specifically, six carotenoids, red-orange pigments with inherent antioxidant capacity, were identified as the main enhanced compounds. This comprehensive approach effectively optimized the culture conditions and medium of a G. hongkongensis strain, resulting in enhanced carotenoid production and antioxidant capacity. Beyond identifying bioactive compounds and their potential cosmetic applications, this study offers insights into the broader industrial applicability of these extracts. It underscores the potential of G. hongkongensis and hints at the future utilization of other untapped sources of rare actinomycetes within the industry.

Targeted Anthocyanin Profiling of Fruits from Three Southern Highbush Blueberry Cultivars Propagated in Colombia.

The blueberry, a deciduous shrub in the Ericaceae family, is celebrated for its delightful flavor, sweetness, and abundance of anthocyanins and antioxidants, qualities that have garnered significant attention for their potential health benefits. Blueberries grown in diverse environments and exhibit varied anthocyanin profiles, often influenced by factors such as altitude and climate. Varietal groups worldwide have been bred and categorized based on their growth habits and specific cold requirements, particularly with southern highbush cultivars thriving in temperate climates, demonstrating tolerance to higher altitudes or cooler climates-a result of hybridizations involving various Vaccinium species. In the Colombian Andes, southern highbush blueberries thrive in unique high-altitude conditions, leading to exceptional quality due to the region's cool climate and specific soil characteristics. In this context, this study aimed to chemically characterize and differentiate three southern highbush blueberry cultivars (i.e., 'Biloxi,' 'Legacy' and 'Sharpblue') cultivated in a Colombian Andean plateau and compare them to three commercially available highbush blueberries. This comprehensive evaluation involved examining total phenols, flavonoids, anthocyanin content, and DPPH· free-radical scavenging capacity, as well as conducting anthocyanin-targeted profiling via HPLC-DAD-HRMS. Through supervised multivariate analyses such as sPLS-DA, this study delved into the pattern recognition of those anthocyanins that could potentially serve as markers for quality and cultivar-related chemical trait determination. These findings locate blueberry-derived anthocyanins in a metabolic context and afford some insights into southern highbush blueberry cultivar differentiation to be used for further purposes.

Susceptibility of Tetranychus urticae to the Alkaloidal Extract of Zanthoxylum schreberi Bark: Phenotypic and Biochemical Insights for Biotechnological Exploitation.

Tetranychus urticae Koch, a phytophagous mite, is one of the most significant crop pests globally. The primary method employed for controlling T. urticae involves chemical means, utilizing synthesized products, posing the risk of developing resistance. The urgency for novel strategies integrated into pest management programs to combat this mite is becoming increasingly imperative. Botanical pesticides emerge as a promising tool to forestall arthropod resistance. Among these, extracts from Rutaceae plants, abundant in bioactive specialized metabolites, have demonstrated potential as insecticides and miticides. In this study, various concentrations of alkaloidal extracts sourced from the bark of Zanthoxylum schreberi J.F.Gmel. (Rutaceae) were evaluated against T. urticae adult females. Furthermore, the extract's combination with three distinct commercial acaricides (i.e., chlorfenapyr, cyflumetofen, and abamectin) was also assessed for this mite. Chemical characterization of the extract via LC-MS allowed for the annotation of various compounds related to ten benzylisoquinoline-derived alkaloids. The extract, both alone and in combination with commercial insecticides, yielded varying responses, inducing over 40% mortality at 2% w/w, demonstrating a 90% repellency rate at the same concentration, and exerting a moderate impact on fecundity. These treatments extended beyond phenotypic responses, delving into the biochemical effects on treated T. urticae females through an exploration of the impact on four enzymes, i.e., acetylcholinesterase (AChE), glutathione S-transferase (GST), esterases (GE), and P450-like monooxygenases (PMO). Employing consensus docking studies and in vitro enzymatic evaluations, it was discovered that the Z. schreberi-derived extract and its constituents significantly affected two key enzymes, AChE and GST (IC50 < 6 µM), which were associated with the phenotypic observations of T. urticae females. The evaluation of alkaloid-rich botanicals showcases promising potential as a relevant biotechnological strategy in addressing mite-related concerns, offering a pathway toward innovative and sustainable pest management solutions.

Down-regulation of human papillomavirus E6 oncogene and antiproliferative effect of Schisandra chinensis and Pueraria lobata natural extracts on Hela cell line.

ETHNOPHARMACOLOGICAL RELEVANCE: Cervical cancer is one of the most common malignancies in women that continues to be a public health problem worldwide. Human papillomavirus (HPV) infection is closely related as the causative agent of almost all cases of cervical cancer. Currently, there is no effective treatment for the persistence of HPV. Although vaccines have shown promising results in recent years, they are still a costly strategy for developing countries and have no therapeutic effect on existing infections, which is why the need arises to search for new strategies that can be used in treatment, suppressing oncogenic HPV and disease progression. Extracts of Schisandra Chinensis and Pueraria lobata have been used in traditional medicine, and it has been shown in recent years that some of their bioactive compounds have pharmacological, antioxidant, antitumor, apoptotic, and proliferation effects in HPV-positive cells. However, its mechanism of action has yet to be fully explored. AIM OF THE STUDY: The following study aimed to determine the chemical composition, antioxidant activity, and potential antiproliferative and viral oncogene effects of natural extracts of S. chinensis and P. lobata on HPV-18 positive cervical cancer cells. MATERIALS AND METHODS: The HPV-18-positive HeLa cells were treated for 24 and 48 h with the ethanolic extracts of S chinensis and P. lobata. Subsequently, cell viability was evaluated using the resazurin method, the effect on the cell cycle of the extracts (1.0, 10, and 100 µg/mL) was measured by flow cytometry, the gene of expression of the E6/E7, P53, BCL-2, and E2F-1 were determined by RT-PCR and the protein expression of p53, Ki-67, x|and Bcl-2 by immunohistochemistry. Additionally, the chemical characterization of the two extracts was carried out using LC-MS, and the total phenolics content (TPC), Total flavonoid content (TFC), and DPPH radical scavenging capacity were determined. Data were analyzed using the Mann-Whitney and Kruskal Wallis U test with GraphPad Prism 6 software. RESULTS: The natural extracts of Schisandra chinensis and Pueraria lobata induced down-regulation of E6 HPV oncogene (p<0.05) and a strong up-regulation of P53 (p<0.05), E2F-1 (p<0.05), and Bcl-2 (p<0.05) gene expression. Simultaneously, the natural extracts tend to increase the p53 protein levels and arrest the cell cycle of HeLa in the G1/S phase (p<0.05). Investigated extracts were characterized by the occurrence of bioactive lignans and isoflavones in S. chinensis and P. lobata, respectively. CONCLUSION: The extracts of S. chinensis and P. lobata within their chemical characterization mainly present lignan and isoflavone-type compounds, which are probably responsible for inhibiting the expression of the HPV E6 oncogene and inducing an increase in the expression of p53, Bcl -2 and E2F-1 producing cell cycle detection in S phase in HeLa cells. Therefore, these extracts are good candidates to continue studying their antiviral and antiproliferative potential in cells transformed by HPV.

Quinolizidine-Type Alkaloids: Chemodiversity, Occurrence, and Bioactivity.

Quinolizidine alkaloids (QAs) are nitrogen-containing compounds produced naturally as specialized metabolites distributed in plants and animals (e.g., frogs, sponges). The present review compiles the available information on the chemical diversity and biological activity of QAs reported during the last three decades. So far, 397 QAs have been isolated, gathering 20 different representative classes, including the most common such as matrine (13.6%), lupanine (9.8%), anagyrine (4.0%), sparteine (5.3%), cytisine (6.5%), tetrahydrocytisine (4.3%), lupinine (12.1%), macrocyclic bisquinolizidine (9.3%), biphenylquinolizidine lactone (7.1%), dimeric (7.1%), and other less known QAs (20.9%), which include several structural patterns of QAs. A detailed survey of the reported information about the bioactivities of these compounds indicated their potential as cytotoxic, antiviral, antimicrobial, insecticidal, anti-inflammatory, antimalarial, and antiacetylcholinesterase compounds, involving favorable putative drug-likeness scores. In this regard, research progress on the structural and biological/pharmacological diversity of QAs requires further studies oriented on expanding the chemical space to find bioactive scaffolds based on QAs for pharmacological and agrochemical applications.

Overview of Updated Control Tactics for Western Flower Thrips.

Frankliniella occidentalis Pergande (Thysanoptera: Thripidae), broadly known as Western flower thrips (WFT), are currently one of the most critical pests worldwide in field and greenhouse crops, and their management is full of yet unsolved challenges derived from their high reproductive potential, cryptic habit, and ability to disperse. The control of this pest relies widely on chemical control, despite the propensity of the species to develop resistance. However, significant advances have been produced through biological and ethological control. Although there has recently been a remarkable amount of new information regarding the management of this pest worldwide, there is no critical analysis of recent developments and advances in the attractive control tactics for WFT, constituting the present compilation's aim. Hence, this narrative review provides an overview of effective control strategies for managing thrips populations. By understanding the pest's biology, implementing monitoring techniques, accurately identifying the species, and employing appropriate control measures, farmers and researchers can mitigate the WFT impact on agricultural production and promote sustainable pest management practices.

Isoflavone Content and Nutritional-Related Properties of Debittered Seeds from Two Andean Lupin (Lupinus mutabilis Sweet) Ecotypes Propagated in Two Soils.

Lupinus mutabilis Sweet is a fabaceous plant native to the Andean highlands and produces seeds with valuable nutritional properties. Thus, as part of our research on native emerging food, the present study aimed at determining some nutritional and functional-related features of seeds from two L. mutabilis ecotypes after propagation in two different substrates commonly found in the Bogotá plateau. Propagated plants produced seeds that, after conventional debittering, exhibited attractive contents of soluble protein (24-39 g/100 g dry seed powder (dsp)), phenolic (787-1003 g/100 g dsp), isoflavone (1-104 g/100 g dsp), and iron (5.3-6.4 g/100 g dsp), as well as antioxidant capacity (39-78 µM/100 g dsp). Higher pH, humidity saturation, organic matter, and total nitrogen of silty loam soil promoted isoflavone accumulation and better antioxidant capacity at pH 4-7, and no soil effect was observed for total phenolic and iron contents. The profiles based on isoflavone aglycones were also recorded by liquid chromatography-mass spectrometry, detecting eleven main compounds with mutabilein as the most abundant isoflavone (38.3-104.3 g/100 g dsp). Finally, a formulation was developed to fabricate an emulsion-type drink based on the debittered, pulverized L. mutabilis seeds, resulting in different emulsifying capacities (19-100%) depending on the biopolymer stabilizer, being xanthan gum the best additive. The findings revealed an attractive Andean lupin profile to be used as a raw food material.

Natural Products for Drug Discovery in the 21st Century: Innovations for Novel Therapeutics.

Natural products (NPs) from plants, fungi, animals, and microorganisms have historically played important roles in drug discovery [...].

Kaurane-Type Diterpenoids as Potential Inhibitors of Dihydrofolate Reductase-Thymidylate Synthase in New World Leishmania Species.

The bifunctional enzyme Dihydrofolate reductase-thymidylate synthase (DHFR-TS) plays a crucial role in the survival of the Leishmania parasite, as folates are essential cofactors for purine and pyrimidine nucleotide biosynthesis. However, DHFR inhibitors are largely ineffective in controlling trypanosomatid infections, largely due to the presence of Pteridine reductase 1 (PTR1). Therefore, the search for structures with dual inhibitory activity against PTR1/DHFR-TS is crucial in the development of new anti-Leishmania chemotherapies. In this research, using the Leishmania major DHFR-TS recombinant protein, enzymatic inhibitory assays were performed on four kauranes and two derivatives that had been previously tested against LmPTR1. The structure 302 (6.3 µM) and its derivative 302a (4.5 µM) showed the lowest IC50 values among the evaluated molecules. To evaluate the mechanism of action of these structures, molecular docking calculations and molecular dynamics simulations were performed using a DHFR-TS hybrid model. Results showed that hydrogen bond interactions are critical for the inhibitory activity against LmDHFR-TS, as well as the presence of the p-hydroxyl group of the phenylpropanoid moiety of 302a. Finally, additional computational studies were performed on DHFR-TS structures from Leishmania species that cause cutaneous and mucocutaneous leishmaniasis in the New World (L. braziliensis, L. panamensis, and L. amazonensis) to explore the targeting potential of these kauranes in these species. It was demonstrated that structures 302 and 302a are multi-Leishmania species compounds with dual DHFR-TS/PTR1 inhibitory activity.

Semiochemicals Associated with the Western Flower Thrips Attraction: A Systematic Literature Review and Meta-Analysis.

The study of the semiochemicals of the western flower thrips (WFT), Frankliniella occidentalis, Pergande (Thysanoptera: Thripidae), is a relevant topic that spans the last two decades. Approximately a hundred articles published on this subject from 2000 to 2022 can be found in academic databases, representing approximately 5% of the research on this important pest. These topics have generated a platform for novel research with a high potential for development. However, to move on to a new research step, an effectiveness evaluation of the compounds discovered so far is necessary. This review conducted a systematic analysis of the research focused on the semiochemicals (kairomones, pheromones, and attractants) for this pest. Papers from the past three decades on WFT attraction to semiochemicals were collected from databases using the Preferred Reporting Items for Systematic Reviews and Meta-Analysis (PRISMA) guidelines. The number of individuals attracted to compounds was extracted from the papers and compiled for analysis. With this information, an attraction ratio was calculated. Forty-one possible attractants were found in the literature, with methyl isonicotinate being the most-studied compound so far, with the third-highest attraction ratio. δ-Decalactone was the compound with the highest attraction ratio, but it was one of the least studied. A meta-analysis of the WFT choosing proportion was performed for the compounds with more trials found in the literature. The predicted mean choice percentages for methyl isonicotinate (MIN) and Lurem-TR, the MIN's commercial product, were 76.6% and 66.6%, respectively. There was a convergence among the analyzed studies showing a high degree of research focus on the same group of nitrogen-containing compounds (mainly the pyridine structure). These findings call for future research to diversify the discovery and evaluation of attractive compounds in this relevant study area.

Antifungal activity against Fusarium oxysporum of quinolizidines isolated from three controlled-growth Genisteae plants: structure-activity relationship implications.

The Genisteae tribe belongs to the Fabaceae family. The wide occurrence of secondary metabolites, explicitly highlighting the quinolizidine alkaloids (QAs), characterizes this tribe. In the present study, twenty QAs (1-20), including lupanine (1-7), sparteine (8-10), lupanine (11), cytisine and tetrahydrocytisine (12-17), and matrine (18-20)-type QAs were extracted and isolated from leaves of three species (i.e., Lupinus polyphyllus ('rusell' hybrid), Lupinus mutabilis, and Genista monspessulana) belonging to the Genisteae tribe. These plant sources were propagated under greenhouse conditions. The isolated compounds were elucidated by analyzing their spectroscopical data (MS, NMR). The antifungal effect on the mycelial growth of Fusarium oxysporum (Fox) of each isolated QA was then evaluated through the amended medium assay. The best antifungal activity was found to be for compounds 8 (IC50 = 16.5 µM), 9 (IC50 = 7.2 µM), 12 (IC50 = 11.3 µM), and 18 (IC50 = 12.3 µM). The inhibitory data suggest that some QAs could efficiently inhibit Fox mycelium growth depending on particular structural requirements deduced from structure-activity relationship scrutinies. The identified quinolizidine-related moieties can be involved in lead structures to develop further antifungal bioactives against Fox.

Second-Generation Enamine-Type Schiff Bases as 2-Amino Acid-Derived Antifungals against Fusarium oxysporum: Microwave-Assisted Synthesis, In Vitro Activity, 3D-QSAR, and In Vivo Effect.

In this manuscript, the synthesis of enamine-type Schiff bases 1−48 derived from the amino acids L-Ala, L-Tyr, and L-Phe was carried out. Their in vitro activity and in vivo protective effect against Fusarium oxysporum were also evaluated through mycelial growth inhibition and disease severity reduction under greenhouse conditions. The in vitro activity of test compounds 1−48 showed half-maximal inhibitory concentrations (IC50) at different levels below the 40 mM range. Deep analysis of the IC50 variations indicated that the size of the substituent on the acetylacetone derivatives and the electronic character on the cyclohexane-3-one fragment influenced the antifungal effect. 3D-QSAR models based on atoms (atom-based approach) were built to establish the structure−activity relationship of the test Schiff bases, showing a good correlation and predictive consistency (R2 > 0.70 and Q2 > 0.60). The respective contour analysis also provided information about the structural requirements for potentiating their antifungal activity. In particular, the amino acid-related fragment and the alkyl ester residue can favor hydrophobic interactions. In contrast, the nitrogen atoms and enamine substituent are favorable regions as H-donating and electron-withdrawing moieties. The most active compounds (40 and 41) protected cape gooseberry plants against F. oxysporum infection (disease severity index < 2), involving adequate physiological parameters (stomatal conductance > 150 mmol/m2s) after 45 days of inoculation. These promising results will allow the design of novel Schiff base-inspired antifungals using 2-amino acids as precursors.

Chemical Characterization of Quality-Related Compounds in Cocoa Matrices: An Overview of Analytical Methods Applied for Their Analysis.

Cocoa currently faces differentiation processes toward niches of specialty products, leading to greater competitiveness for producers who must compete with products differentiated by their integral quality regarding their organoleptic characteristics, such as fine-flavor cocoa and their functional characteristics. Quality is influenced by the genetic variety of the cultivars on the one hand, and the correct postharvest processing operations of cocoa seeds, on the other. During the transformation operations, the native chemical compounds of the seeds, especially proteins, carbohydrates, and polyphenols, are transformed and generate other compounds called flavor precursors, which are responsible for defining the product quality. In this sense, the analysis of the most relevant chemical compounds in cocoa is essential to guarantee higher overall quality. Similarly, understanding the fundamental aspects that affect fine-flavor cocoa production is crucial for improving transformation processes. Therefore, reliable and robust analytical techniques are required to detect and quantify these chemical compounds. This review highlights the main techniques used to analyze essential cocoa metabolites and derived products throughout all postharvest transformation stages: from cocoa seeds to chocolate bar, offering an overview of the sample preparation methods and the analytical and imaging methodologies often employed to characterize qualifying cocoa products.

Machine-Learning- and Structure-Based Virtual Screening for Selecting Cinnamic Acid Derivatives as Leishmania major DHFR-TS Inhibitors.

The critical enzyme dihydrofolate reductase-thymidylate synthase in Leishmania major (LmDHFR-TS) serves a dual-purpose role and is essential for DNA synthesis, a cornerstone of the parasite's reproductive processes. Consequently, the development of inhibitors against LmDHFR-TS is crucial for the creation of novel anti-Leishmania chemotherapies. In this study, we employed an in-house database containing 314 secondary metabolites derived from cinnamic acid that occurred in the Asteraceae family. We conducted a combined ligand/structure-based virtual screening to identify potential inhibitors against LmDHFR-TS. Through consensus analysis of both approaches, we identified three compounds, i.e., lithospermic acid (237), diarctigenin (306), and isolappaol A (308), that exhibited a high probability of being inhibitors according to both approaches and were consequently classified as promising hits. Subsequently, we expanded the binding mode examination of these compounds within the active site of the test enzyme through molecular dynamics simulations, revealing a high degree of structural stability and minimal fluctuations in its tertiary structure. The in silico predictions were then validated through in vitro assays to examine the inhibitory capacity of the top-ranked naturally occurring compounds against LmDHFR-TS recombinant protein. The test compounds effectively inhibited the enzyme with IC50 values ranging from 6.1 to 10.1 µM. In contrast, other common cinnamic acid derivatives (i.e., flavonoid glycosides) from the Asteraceae family, such as hesperidin, isovitexin 4'-O-glucoside, and rutin, exhibited low activity against this target. The selective index (SI) for all tested compounds was determined using HsDHFR with moderate inhibitory effect. Among these hits, lignans 306 and 308 demonstrated the highest selectivity, displaying superior SI values compared to methotrexate, the reference inhibitor of DHFR-TS. Therefore, continued research into the anti-leishmanial potential of these C6C3-hybrid butyrolactone lignans may offer a brighter outlook for combating this neglected tropical disease.

Síntesis y actividad antifúngica in vitro frente a Fusarium oxysporum de amidas N-alquilsustituidas derivadas de 2-aminoácidos

Una serie de amidas N-alquilsustituidas 1-16 fueron sintetizadas a partir de malonato de dietilo y ésteres de alquilo derivados de los aminoácidos L-triptófano, L-alanina, L-fenilalanina y L-tirosina. Los métodos de síntesis empleados involucraron calentamiento por irradiación de microondas empleando tanto un ácido de Lewis (AlCl3) o 4-dimetilaminopiridina (DMAP) como catalizador y auxiliar nucleofílico, respectivamente. Los resultados sugieren que el uso de irradiación de microondas y de DMAP conlleva mejores rendimientos en un tiempo de reacción más corto. Para ilustrar las diferencias observadas, se presentan las propuestas mecanísticas de cada método de reacción para la formación de amidas N-alquilsustituidas. Finalmente, las amidas sintetizadas se evaluaron en condiciones in vitro frente a Fusarium oxysporum; mostraron actividad antifúngica a diferentes niveles (0,40 mM < IC50 < 29,1 mM), lo cual indicó que las variaciones de la actividad observada de este grupo de compuestos pueden deberse al efecto de la amida acíclica como bioisóstero no clásico de algunas fitoalexinas heterocíclicas.

N-alkyl substituted amides 1-16 were synthesized from diethyl malonate and alkyl esters derived from the amino acids L -tryptophan, L -alanine, L -phenylalanine, and L -tyrosine. In addition, a microwave-assisted protocol was employed using a Lewis acid (AlCl3) or dimethylaminopyridine (DMAP) as a catalyst and nucleophilic auxiliary, respectively, affording the desired compounds. The results suggest that DMAP-catalyzed reactions under microwave irradiation yield higher during short reaction times. Each reaction method's mechanistic proposals for forming N-alkyl-substituted amides are presented to illustrate the observed differences. The synthesized amides were evaluated under in vitro conditions against Fusarium oxysporum. The compounds exhibited antifungal activity at different levels (0.40 mM < IC50 < 29.1 mM). These results indicated that the observed activity variations of this compound group might be due to the effect of acyclic amide as a non-classical bioisostere of some heterocyclic phytoalexins.

Uma série de amidas N-alquil substituídas foram sintetizadas a partir de malonato de dietila e ésteres alquílicos derivados dos aminoácidos ʟ-triptofano, L -alanina, L-fenilalanina e L-tirosina. Os métodos de síntese empregados foram realizados usando aquecimento por irradiação de micro-ondas empregando um ácido de Lewis (AlCl3) ou dimetilaminopiridina (DMAP) como catalisador. Os resultados sugerem que a irradiação de micro-ondas usando DMAP leva a melhores rendimentos em um tempo de reação mais curto. Para ilustrar as diferenças observadas, são apresentadas as propostas mecanísticas de cada método de reação para a formação de amidas N-alquilsubstituídas. Finalmente, as amidas sintetizadas foram avaliadas in vitro contra Fusarium oxysporum, mostrando atividade antifúngica em diferentes níveis (0.40 mM < IC50 < 29.1 mM), o que indica que as variações observadas na atividade desse grupo de compostos podem ser devidas ao efeito de amida acíclica como um bioisóstero não clássico de algumas fitoalexinas heterocíclicas.

Enfermedad del desgaste en praderas de Thalassia testudinum (Hydrocharitaceae) y su relación con el perfil metabólico / Wasting disease in Thalassia testudinum (Hydrocharitaceae) meadows and its relationship with metabolic profile

Resumen Introducción: Los protistas del género Labyrinthula causan la denominada "Enfermedad del desgaste" en el pasto marino, Thalassia testudinum. Desde el 2008 los monitoreos en el Caribe colombiano han mostrado variación espacial y temporal en la incidencia de la enfermedad, pero sin la alta mortalidad observada en otras regiones del mundo. Objetivo: Analizar algunos parámetros epidemiológicos en T. testudinum y comparar metabolitos entre plantas sanas e infectadas. Métodos: Registramos la severidad, incidencia y prevalencia de esta enfermedad en el Parque Nacional Natural Tayrona e Isla de Providencia, y analizamos muestras de agua y sedimentos. Además, aplicamos cromatografía líquida y de gases, junto con espectrometría de masas, a extractos metanólicos de muestras de hojas y rizomas de brotes sanos e infectados. Resultados: Las praderas se encontraban en buen estado, a pesar de la escasez de brotes de fanerógamas marinas en Tayrona y una alta incidencia (15 %) y severidad (355 %) de la enfermedad en Providencia. Las plantas infectadas tenían niveles más bajos de fenoles, flavonoides y azúcares. Las flavonas sulfatadas con aglicona luteolina y diosmetina, los esteroles (sitosterol y estigmasterol) y las oxilipinas volátiles se acumularon en las hojas (3-hidroxi-2-isopentanona) y los ácidos isopentanoico y octadecatrienoico en los rizomas. Conclusiones: Estos pastos marinos colombianos tienen producción diferencial de metabolitos. Probablemente como una defensa exitosa, aún a niveles bajos de severidad (0.1 %) e incidencia (1 %) de la enfermedad.

Abstract Introduction: Protists of the genus Labyrinthula cause the so-called "Wasting Disease" in seagrass, Thalassia testudinum. Monitoring in the Colombian Caribbean since 2008 has shown spatial and temporal variation in the disease's incidence, but without the high mortality observed in other regions of the world. Objective: To analyze some epidemiological parameters in T. testudinum and to compare metabolites between healthy and infected plants. Methods: We recorded severity, incidence and prevalence of this disease in Tayrona National Natural Park and Providencia Island, and we analyze water and sediment samples. Additionally, we applied gas and liquid chromatography, coupled with mass spectrometry, to methanolic extracts from leaf and rhizome samples of healthy and infected shoots. Results: The meadows were in good condition, despite the scarce seagrass shoots in Tayrona and a high incidence (15 %) and severity (35.5 %) of the disease in Providencia. Infected plants had lower levels of phenols, flavonoids and sugars. Sulphated flavones with aglycone luteolin and diosmetin, sterols (sitosterol and stigmasterol) and volatile oxylipins are accumulated in leaves (3-hydroxy-2-isopentanone) and isopentaenoic and octadecatrienoic acids in rhizomes. Conclusions: These Colombian seagrasses have differential production of metabolites. Probably as a successful defense, even at low levels of severity (0.1 %) and incidence (1 %) of the disease.

Specialized Metabolism of Gordonia Genus: An Integrated Survey on Chemodiversity Combined with a Comparative Genomics-Based Analysis.

Members of the phylum Actinomycetota (formerly Actinobacteria) have historically been the most prolific providers of small bioactive molecules. Although the genus Streptomyces is the best-known member for this issue, other genera, such as Gordonia, have shown interesting potential in their specialized metabolism. Thus, we combined herein the result of a comprehensive literature survey on metabolites derived from Gordonia strains with a comparative genomic analysis to examine the potential of the specialized metabolism of the genus Gordonia. Thirty Gordonia-derived compounds of different classes were gathered (i.e., alkaloids, amides, phenylpropanoids, and terpenoids), exhibiting antimicrobial and cytotoxic activities, and several were also isolated from Streptomyces (e.g., actinomycin, nocardamin, diolmycin A1). With the genome data, we estimated an open pan-genome of 57,901 genes, most of them being part of the cloud genome. Regarding the BGCs content, 531 clusters were found, including Terpenes, RiPP-like, and NRPS clusters as the most frequent clusters. Our findings demonstrated that Gordonia is a poorly studied genus in terms of its specialized metabolism production and potential applications. Nevertheless, given their BGCs content, Gordonia spp. are a valuable biological resource that could expand the chemical spectrum of the phylum Actinomycetota, involving novel BGCs for inspiring innovative outlines for synthetic biology and further use in biotechnological initiatives. Therefore, further studies and more efforts should be made to explore different environments and evaluate other bioactivities.

Mono-n-butyl Malate-Derived Compounds from Camu-camu (Myrciaria dubia) Malic Acid: The Alkyl-Dependent Antihyperglycemic-Related Activity.

Malic acid derivatives from camu-camu (Myrciaria dubia) fruit exhibited a strong in vitro inhibitory activity toward pancreatic α-amylase and α-glucosidase enzymes. During a bioguided chromatographic fractionation process of the whole fruit (pulp and peelings) polar extract, isomers (S)-4-butoxy-2-hydroxy-4-oxobutanoic acid (1) and (S)-4-butoxy-3-hydroxy-4-oxobutanoic acid (2) (84:16) were isolated and identified as a potent inhibitor of α-amylase (IC50= 11.69 ± 1.75 µg/mL) and α-glucosidase (IC50 = 102.69 ± 4.16 µg/mL). The chemical structures were confirmed by HPLC-ESIMS and 1H and 13C NMR (one- and two-dimensional) analyses. The structure-based virtual screening demonstrated that the aliphatic moiety plays a significant role in the binding mode of the test alkyl malate esters. Compound 1 exhibited the best interaction profile to bind both enzymes, having key structural features to form relevant contacts by involving adequate enzyme-ligand complex stabilization and compactness over time.

Freshwater-Derived Streptomyces: Prospective Polyvinyl Chloride (PVC) Biodegraders.

Polyvinyl chloride (PVC) is widely used in industrial applications, such as construction and clothing, owing to its chemical, physical, and environmental resistance. Owing to the previous characteristics, PVC is the third most consumed plastic worldwide and, consequently, an increasing waste accumulation-related problem. The current study evaluated an in-house collection of 61 Actinobacteria strains for PVC resin biodegradation. Weight loss percentage was measured after the completion of incubation. Thermo-gravimetric analysis was subsequently performed using the PVC incubated with the three strains exhibiting the highest weight loss. GC-MS and ionic exchange chromatography analyses were also performed using the culture media supernatant of these three strains. After incubation, 14 strains had a PVC weight loss percentage higher than 50% in ISP-2 broth. These 14 strains were identified as Streptomyces strains. Strains 208, 250, and 290 showed the highest weight loss percentages (57.6-61.5% range). The thermal stability of PVC after bacterial exposure using these three strains was evaluated, and a modification of the representative degradation stages of nonincubated PVC was observed. Additionally, GC-MS analysis revealed the presence of aromatic compounds in the inoculated culture media, and ionic exchange chromatography showed chloride release in the supernatant. A mathematical relation between culture conditions and PVC weight loss was also found for strains 208 and 290, showing an accuracy up to 97.99%. These results highlight the potential of the freshwater-derived Streptomyces strains as candidates for the PVC biodegradation strategy and constitute the first approach to a waste management control scale-up process.

GC/MS-Based Fingerprinting Reveals Two Chemotypes in the Leaf Essential Oils from Magnolia grandiflora Trees within The Urban Forestry of a Colombian Andean Plateau.

Magnolia grandiflora is an aromatic plant widely distributed around the world. In Colombia, and more specifically in Bogotá, M. grandiflora has been introduced as part of urban forestry programs, and their specimens are therefore subjected to several environments. Nevertheless, there are no previous studies on the chemical composition of such plants. Hence, the characterization of the essential oil from 20 specimens of M. grandiflora from Bogotá, Colombia, by GC/MS was carried out here. Two different chemotypes were found. While one was characterized by monoterpenes α-pinene, ß-pinene, and limonene, the other contained mainly sesquiterpenes ß-elemene, bicyclogermacrene, and germacrene D. Multivariate statistical analyses confirmed their existence and helped to identify variations within and between chemotypes. Furthermore, differential expression of genes encoding the terpene synthases Mg25 and Mg17 could arguably be responsible for the characteristic compositions of both chemotypes, as suggested by rational biosynthetic analysis of the most contrasting metabolites.