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(2 Z )- Lachnophyllum methyl ester and (4 Z )- Lachnophyllum lactone were recently identified as major components in essential oils and extracts of Conyza bonariensis from Togo. Extended biological evaluation of these acetylenic compounds was however hampered by the reduced amounts isolated. A synthetic route was designed providing access to larger quantities of these two natural products as well as to original non-natural analogs with the prospect of exploring for the first time the structure-activity relationships in this series. Using LC/MS analysis, synthetic samples allowed confirming the presence of the two previously isolated natural products in plant extracts obtained by the accelerated solvent extraction technique. The nematocidal activity of the synthesized compounds confirmed the potency of the natural products, which remain the most active among all analogs tested. The synthesized compounds were also assessed against Leishmania infantum axenic amastigotes and the Mycobacterium tuberculosis H 37 Rv pathogenic strain. (2 Z )- Lachnophyllum methyl ester, (4 Z )- Lachnophyllum lactone and lactone analogs exhibited the strongest antileishmanial potency. As expected, a longer alkyl chain was necessary to observe significant antimycobacterial activity. The lactone analog bearing a C10 lipophilic appendage displayed the highest antimycobacterial potency. The notable activities of lactones, naturally occurring or analogs, either nematicidal, antileishmanial or antimycobacterial, were compared to their cytotoxicity for mammalian cells and revealed moderate selectivity index values. In this regard, the innocuous (2 Z )- Lachnophyllum methyl ester and its analogs open up more promising perspectives for the discovery of bioactive agents to protect both agricultural crops and human health.

Eggs, as a crucial source of essential nutrients for consumers, possess a high nutritional value owing to their rich composition of vital components essential for human health. While previous research has extensively investigated genetic factors influencing egg quality, there has been a limited focus on exploring the impact of specific strains, particularly within the African context, on the polar metabolite profile of eggs. In this extensive study, we conducted an untargeted analysis of the chemical composition of both albumen and yolk from 3 distinct strains of hens-Blue Holland, Sasso, and Wassache-raised under identical feeding conditions. Utilizing gas chromatography coupled with mass spectrometry (GC-MS), we meticulously examined amino acids, carbohydrates, fatty acids, and other small polar metabolites. In total, 38 and 44 metabolites were identified in the whites and yolk, respectively, of the 3 studied strains. The application of chemometric analysis revealed notable differences in metabolite profiles with 8 relevant metabolites in each egg part. These metabolites include amino acids (N-α-Acetyl-L-lysine, lysine, L-valine, L-Tryptophan), fatty acids (oleic acid, linoleic acid, palmitic acid and stearic acid), and carbohydrates (d-glucose, maltose, lactose). These findings shed light on strain-specific metabolic nuances within eggs, emphasizing potential nutritional implications. The ensuing discussion delves into the diverse metabolic pathways influenced by the identified metabolites, offering insights that contribute to a broader understanding of egg composition and its significance in tailoring nutritional strategies for diverse populations., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Gibberellin derivatives are a family of tetracyclic diterpenoid plant hormones used in agriculture as plant growth regulators included in the European Directive 91/414. In the pesticide peer review process and to assess their toxicological relevance and product chemical equivalence, the European Food Safety Authority (EFSA) highlighted data gaps such as the identification of hydrolysis products and unknown impurities. The aspect of impurity characterization and quantitation is challenging and requires the use of hyphenated analytical techniques. In this regard, we used an LC-QTOF/MS and NMR analysis for the characterization of gibberellic acid impurities found in technical products. Gibberellic acid impurities such as gibberellin A1 ( GA 1 ), 3-isolactone gibberellic acid ( iso-GA 3 ), gibberellenic acid, 1α,2α-epoxygibberellin A3 ( 2-epoxy- GA 3 ), and (1α,2β,3α,4bβ,10β)-2,3,7-trihydroxy-1-methyl-8-methylenegibb-4-ene-1,10-dicarboxylic acid were identified and successfully characterized. Moreover, an in silico investigation on selected gibberellic acid impurities and derivatives and their interactions with a gibberellin insensitive dwarf1 (GID1) receptor has been carried out by means of induced fit docking (IFD), generalized-Born surface area (MM-GBSA), and metadynamics (MTD) experiments. A direct HPLC method with DAD and MS for the detection of gibberellic acid and its impurities in a technical sample has been developed. Moreover, by means of the in silico characterization of the GID1 receptor-binding pocket, we investigated the receptor affinity of the selected gibberellins, identifying compounds ( 2 ) and ( 4 ) as the most promising hit to lead compounds., Competing Interests: The authors declare no competing financial interest., (© 2023 The Authors. Published by American Chemical Society.)

The present study reports on the powerful nematicidal activity of a series of electron-deficient alkynes against the root-knot nematode Meloidogyne incognita (Kofoid and White) Chitwood. Interestingly, we found that the conjugation of electron-withdrawing carbonyl groups to an alkyne triple bond was extremely proficient in inducing nematode paralysis and death. In particular, dimethylacetylenedicarboxylate ( 10 ), 3-butyn-2-one ( 1 ), and methyl propiolate ( 4 ), with EC 50/48 h of 1.54 ± 0.16, 2.38 ± 0.31, and 2.83 ± 0.28 mg/L, respectively, were shown to be the best tested compounds. Earlier studies reported on the ability of alkynoic esters and alkynones to induce a chemoselective cysteine modification of unprotected peptides. Thus, also following our previous findings on the impairment of vacuolar-type proton translocating ATPase functionality by activated carbonyl derivatives, we speculate that the formation of a vinyl sulfide linkage might be responsible for the nematicidal activity of the presented electron-deficient alkynes.

Reverse transcriptase (RT)-associated DNA polymerase (RDDP) and ribonucleaser H (RNase H) functions are both essential for HIV-1 genome replication, and the identification of new inhibitors to block both of them is a goal actively pursued by the scientific community. In this field, natural extracts have shown a great potential as source of new antivirals. In the present work, we investigated the effect of Uvaria angolensis extracts on the HIV-1 reverse transcriptase-associated DNA polymerase and ribonuclease H activities. The U. angolensis stem bark methanol extract inhibit both HIV-1 RNase H function and RDDP activity with IC 50 values of 1.0 ± 0.2 and 0.62 ± 0.15 μg/mL, respectively and, after been fractionated with different solvents, its solid residue showed an IC 50 of 0.10 ± 0.03 and of 0.23 ± 0.04 μg/mL against RNase H and RDDP, respectively, hence laying the bases for further studies for identification of single active components.

We investigated Solanum nigrum (seeds) and Datura stramonium (shoots) against root-knot nematodes in terms of J2 paralysis and egg hatch inhibition (methanol extract), as well as inhibition of nematode development in host roots (soil amending with either S. nigrum seeds' or D . stramonium shoots' meal). Datura stramonium was found equally effective at inhibiting motility of Meloidogyne incognita and Meloidogyne javanica (both EC 50  = 427 μg mL -1 at 3 day), but inhibition occurred more quickly for M. incognita (1 day). Solanum nigrum was faster and more effective at inhibiting motility of M. incognita than M. javanica (EC 50  = 481 and 954 μg mL -1 at 3 day, respectively). Datura stramonium was slower, but eventually more potent in decreasing egg hatch and cell division in M. incognita eggs, than S. nigrum . Specifically, D. stramonium significantly inhibited cell division in eggs immersed in at least 100 and 1 μg mL -1 at Day 6 and 10, respectively. Solanum nigrum impeded cell division in un-differentiated eggs immersed in not less than 10 and 100 μg mL -1 after days 2 and 6, respectively. Both extracts were similar in suppressing J2 exclosure but D. stramonium was effective in smaller test concentrations. Specifically, D. stramonium suppressed J2 emerging from eggs immersed in 10 μg mL -1 at day2, and in at least 1 μg mL -1 at day 6. Solanum nigrum significantly reduced J2 hatch from eggs immersed in a minimum of 100 μg mL -1 at day 2 and not less than 1,000 μg mL -1 at day 6. In pots, powdered S. nigrum seeds meal was more active than D. stramonium and the respective EC 50 females/ g values for M. incognita were 1.13 and 11.4 mg g -1 of soil, respectively. The chemical composition of active extracts was determined after derivatization by GC-MS. Chemical analysis of active extracts showed the presence of fatty acids with known nematicidal activity., (© The Society of Nematologists.)

After 2 months from the infestation of tomato plants with the root-knot nematode (RKN) Meloidogyne incognita, we performed a gas chromatography-mass spectrometry untargeted fingerprint analysis for the identification of characteristic metabolites and biomarkers. Principal component analysis, and orthogonal projections to latent structures discriminant analysis suggested dramatic local changes of the plant metabolome. In the case of tomato leaves, β-alanine, phenylalanine, and melibiose were induced in response to RKN stimuli, while ribose, glycerol, myristic acid, and palmitic acid were reduced. For tomato stems, upregulated metabolites were ribose, sucrose, fructose, and glucose, while fumaric acid and glycine were downregulated. The variation in molecular strategies to the infestation of RKNs may play an important role in how Solanum lycopersicum and other plants adapt to nematode parasitic stress.

Different maleimide derivatives were synthesized and assayed for their in vitro activity on the soil inhabiting, plant-parasitic nematode Meloidogyne incognita, also known as root-knot nematode. The compounds maleimide, N-ethylmaleimide, N-isopropylmaleimide, and N-isobutylmaleimide showed the strongest nematicidal activity on the second stage juveniles of the root-knot nematode with EC50/72h values of 2.6 ± 1.3, 5.1 ± 3.4, 16.2 ± 5.4, and 19.0 ± 9.0 mg/L, respectively. We also determined the nematicidal activity of copper sulfate, finding an EC50 value of 48.6 ± 29.8 mg/L. When maleimide at 1 mg/L was tested in combination with copper sulfate at 50 mg/L, we observed 100% mortality of the nematodes. We performed a GC-MS metabolomics analysis after treating nematodes with maleimide at 8 mg/L for 24 h. This analysis revealed altered fatty acids and diglyceride metabolites such as oleic acid, palmitic acid, and 1-monopalmitin. Our results suggest that maleimide may be used as a new interesting building block for developing new nematicides in combination with copper salts.

A series of aryl hydrazones were synthesized and in vitro assayed for their activity on the root-knot nematode Meloidogyne incognita. The phenylhydrazones of thiophene-2-carboxyaldehyde 5, 3-methyl-2-thiophenecarboxyaldehyde, 6, and salicylaldehyde, 2, were the most potent with EC50/48h values of 16.6 ± 2.2, 23.2 ± 2.7, and 24.3 ± 1.4 mg/L, respectively. A GC-MS metabolomics analysis, after in vitro nematode treatment with hydrazone 6 at 100 mg/L for 12 h, revealed elevated levels of fatty acids such as lauric acid, stearic acid, 2-octenoic acid, and palmitic acid. Whereas control samples showed the highest levels of monoacylglycerols such as monostearin and 2-monostearin, surprisingly, 2 h after treatment with hydrazone 6, nematodes excreted 3 times the levels of ammonia eliminated in the same conditions by controls. Thus, phenylhydrazones may represent a good scaffold in the discovery and synthesis of new nematicidal compounds, and a metabolomics approach may be helpful in understanding their mechanisms of toxicity and mode of action.

Research on new pesticides based on plant extracts, aimed at the development of nontoxic formulates, has recently gained increased interest. This study investigated the use of the volatilome of rucola (Eruca sativa) as a powerful natural nematicidal agent against the root-knot nematode, Meloidogyne incognita. Analysis of the composition of the volatilome, using GC-MS-SPME, showed that the compound (Z)-3-hexenyl acetate was the most abundant, followed by (Z)-3-hexen-1-ol and erucin, with relative percentages of 22.7 ± 1.6, 15.9 ± 2.3, and 8.6 ± 1.3, respectively. Testing of the nematicidal activity of rucola volatile compounds revealed that erucin, pentyl isothiocyanate, hexyl isothiocyanate, (E)-2-hexenal, 2-ethylfuran, and methyl thiocyanate were the most active with EC50 values of 3.2 ± 1.7, 11.1 ± 5.0, 11.3 ± 2.6, 15.0 ± 3.3, 16.0 ± 5.0, and 18.1 ± 0.6 mg/L, respectively, after 24 h of incubation. Moreover, the nematicidal activity of fresh rucola used as soil amendant in a containerized culture of tomato decreased the nematode infection in a dose-response manner (EC50 = 20.03 mg/g) and plant growth was improved. On the basis of these results, E. sativa can be considered as a promising companion plant in intercropping strategies for tomato growers to control root-knot nematodes.