Phenolics from Nigella sativa L. straw: Characterization and insecticidal activity against Agrotis ipsilon (Hüfnagel)

The excessive production of food and agro-waste has become a significant problem for society, the economy, and the environment. To meet the growing demand for food free from harmful synthetic insecticides, a recent study has investigated the potential use of an ethanolic extract obtained from the straw of Nigella sativa L., a byproduct of seed collection, as a bioinsecticide. The study also evaluated its in-vitro and in-silico acetylcholinesterase (AChE) inhibitory potential against the Agrotis ipsilon (Hufnagel) moth species, which is known to cause damage to various crops and ornamental plants. The high-performance liquid chromatography examination revealed that the ethanolic N. sativa straw extract contained 18 phenolics, including 3 simple phenols, 8 phenolic acids, and 7 flavonoids. Catechol (330.14 μg/ml), chlorogenic (169.23 μg/ml), and gallic (110.93 μg/ml) acids were the predominant phenolics. On the other hand, catechin (94.07 μg/ml), naringenin (91.99 μg/ml), and rutin (78.16 μg/ml) were the major flavonoids identified in the extract. The insecticidal activity of the extract against the 4th larval instar of A. ipsilon was evaluated using four concentrations (1.25–10 %). The study found that higher extract concentrations led to increased mortality in the larvae. Specifically, the concentration of 10 % resulted in the highest mortality rate of 96.67 %. Lower concentrations of 5 %, 2.5 %, and 1.25 % resulted in mortality rates of 51.11 %, 18.89 %, and 9.17 %, respectively. The extract also showed higher activity against AChE in larval tissue, with an inhibition percentage of 65.2 % after 24 h of treatment. Docking experiments confirmed that ellagic acid and apigenin had higher binding affinity than the control (lanate). These results demonstrate the potential of utilizing agricultural waste like N. sativa straw to create innovative and sustainable bioinsecticides

Effect of bio-stimulants on growth and chemical composition of mahogany seedlings grown under treated wastewater (TWW)

A pot experiment was carried out to study the effect of treated waste water (TWW) on mahogany seedlings and the role of bio-stimulants in alleviating the harmful impacts, using –6- months' old seedlings.  The TWW was used in 3 types coded as 75%WW/25%PW, 50%WW/50%PW and 25%WW/75%PW, according the ratio between treated wastewater (WW) and potable water (PW).  All seedlings grown under the different types of TWW treatments were sprayed with some bio stimulants. The results revealed that irrigating mahogany seedlings with 25WW/ 75PW, significantly increased plant height, improved the formation of leaves, fresh weight leaves, 25WW/ 75PW increased total indoles whereas using 75WW/25PW or 50WW/50PW, for irrigation produced thicker and heavier FW of stems. FW of leaves with 50WW/50PW gave the heaviest fresh and dry weights of leave and roots diameter, total phenols, free proline and total soluble sugars. The treatment of 75WW/25PW formed significantly longer roots, both 75WW/25PW 0r 50WW/50PW, insignificantly increased fresh weight of roots. All bio-stimulants significantly increased plant height and seaweed extract, salicylic acid and Pot. silicate were the most effective. PS treatment exhibited the thickest stems.&nbsp

Spermaurin, an La1-like peptide from the venom of the scorpion Scorpio maurus palmatus , improves sperm motility and fertilization in different mammalian species

International audienceSTUDY QUESTIONIs it possible to identify original compounds that are able to enhance sperm motility from the venom of the scorpion Scorpio maurus palmatus?SUMMARY ANSWERWe identified a potent disulfide-rich peptide (DRP) of 73 amino acids that significantly improved the motility of fresh and frozen-thawed sperm in different mammalian species, including human, and improved fertilization outcome in mouse IVF experiments.WHAT IS KNOWN ALREADYAny disturbance of sperm motility has a strong impact on fertilization and can lead to subfertility or infertility. Significant efforts have, therefore,  been made to identify pharmacological drugs that might improve sperm motility. Such compounds are particularly useful in azoospermia to improve testicular sperm extraction and in the domain of cryopreservation because the motility of frozen-thawed sperm is reduced.STUDY DESIGN, SIZE, DURATIONThis was a basic science/medical research study aimed at identifying original compounds from a library of venoms able to enhance mammalian sperm motility, including human. We first identified in the venom of a scorpion S. m. palmatus a fraction able to potently activate sperm motility. We next purified and characterized the compound by liquid chromatography, mass spectrometry and peptide synthesis. Finally, the potency and toxicity of both purified and synthetic versions of the identified compound on sperm motility were assessed using different in vitro tests in different mammalian species.PARTICIPANTS/MATERIALS, SETTING, METHODS For human sperm, biological samples were collected from normozoospermic donors and subfertile patients attending a reproduction department for diagnostic semen analysis. Testicular sperm was collected from cynomolgus monkeys (Macaca fascicularis) euthanized for the needs of specific authorized research projects. The peptide was also tested on bovine and mouse epidydimal sperm. We measured different sperm motility parameters with a computer-assisted sperm analysis system in the presence or absence of the peptide.MAIN RESULTS AND THE ROLE OF CHANCESize exclusion chromatography enabled us to isolate a fraction of the venom of S. m. palmatus able to increase sperm motility. By liquid chromatography and mass spectrometry, a peptide comprising 73 amino acids with 4 disulfide bridges was identified as responsible for the biological activity and called ‘spermaurin’. The identity of spermaurin was confirmed by chemical synthesis. We showed that the peptide increased the motility of fresh and frozen-thawed human sperm. We observed that the potency of the peptide was higher on fresh ejaculated spermatozoa with a low motility, achieving a 100% increase of curvilinear velocity in poorly performing sperm. We also demonstrated that peptide is effective on bovine and mouse fresh epididymal, bovine frozen-thawed ejaculated and fresh non-human primate testicular sperm. Finally, in mouse IVF, the production of 2-cell embryos was increased by 24% when sperm were treated with the peptide.LIMITATIONS, REASONS FOR CAUTIONThis work is an in vitro evaluation of the ability of spermaurin to improve sperm motility parameters. Another limitation of this study is the small number of human sperm samples tested with the natural (n = 36) and synthetic (n = 12) peptides. Moreover, the effect of the peptide on IVF outcome was only tested in mouse and further tests with human and bovine gametes are required to confirm and extend this result in other mammalian species.WIDER IMPLICATIONS OF THE FINDINGSThis work confirms our initial study showing that venoms represent an interesting source of molecules that are able to modify sperm physiology. Moreover, this work presents the first demonstrated biological action of a venom peptide from the scorpion S. m. palmatus with sequence similarities to La1 peptide from Liocheles australasiae (Wood scorpion), a widespread family of DRPs.STUDY FUNDING/COMPETING INTEREST(S)This work is part of the project ‘LAB COM-14 LAB7 0004 01-LIPAV’, funded by the program LabCom 2014 from t e French Research Agency (ANR). Dr Arnoult reports grants from IMV Technologies during the conduct of the study. In addition, Drs Arnoult, Martinez, Ray and Schmitt have a patent EP16305642.7 pending containing some of the information presented in this manuscript

Guidelines for the use and interpretation of assays for monitoring autophagy (4th edition)

In 2008, we published the first set of guidelines for standardizing research in autophagy. Since then, this topic has received increasing attention, and many scientists have entered the field. Our knowledge base and relevant new technologies have also been expanding. Thus, it is important to formulate on a regular basis updated guidelines for monitoring autophagy in different organisms. Despite numerous reviews, there continues to be confusion regarding acceptable methods to evaluate autophagy, especially in multicellular eukaryotes. Here, we present a set of guidelines for investigators to select and interpret methods to examine autophagy and related processes, and for reviewers to provide realistic and reasonable critiques of reports that are focused on these processes. These guidelines are not meant to be a dogmatic set of rules, because the appropriateness of any assay largely depends on the question being asked and the system being used. Moreover, no individual assay is perfect for every situation, calling for the use of multiple techniques to properly monitor autophagy in each experimental setting. Finally, several core components of the autophagy machinery have been implicated in distinct autophagic processes (canonical and noncanonical autophagy), implying that genetic approaches to block autophagy should rely on targeting two or more autophagy-related genes that ideally participate in distinct steps of the pathway. Along similar lines, because multiple proteins involved in autophagy also regulate other cellular pathways including apoptosis, not all of them can be used as a specific marker for bona fide autophagic responses. Here, we critically discuss current methods of assessing autophagy and the information they can, or cannot, provide. Our ultimate goal is to encourage intellectual and technical innovation in the field