Molecular Networking-Guided Isolation of New Etzionin-Type Diketopiperazine Hydroxamates from the Persian Gulf Sponge Cliona celata

The Persian Gulf is a unique and biologically diverse marine environment dominated by invertebrates. In continuation of our research interest in the chemistry and biological activity of marine sponges from the Persian Gulf, we selected the excavating sponge Cliona celata for detailed metabolome analyses, in vitro bioactivity screening, and chemical isolation studies. A UPLC-MS/MS (MS²) molecular-networking-based dereplication strategy allowed annotation and structural prediction of various diketopiperazines (DKPs) and etzionin-type diketopiperazine hydroxamates (DKPHs) in the crude sponge extract. The molecular-networking-guided isolation approach applied to the crude extract afforded the DKPH etzionin (1) and its two new derivatives, clioetzionin A (2) and clioetzionin B (3). Another new modified DKP (4) was identified by MS/MS analyses but could not be isolated in sufficient quantities to confirm its structure. The chemical characterization of the purified DKPHs 1–3 was performed by a combination of 1D and 2D NMR spectroscopy, HRMS, HRMS/MS, and [α]_D analyses. Compounds 1 and 2 exhibited broad antibacterial, antifungal, and anticancer activities, with IC₅₀ values ranging from 19.6 to 159.1 µM. This is the first study investigating the chemical constituents of a C. celata specimen from the Persian Gulf. It is also the first report of full spectroscopic data of etzionin based on extensive spectroscopic analyses.     

Physical properties of structural soils containing waste materials to achieve urban greening

Purpose

The densification and expansion of urban areas will increase the streams of waste materials such as bricks, concrete and street sweeping waste. In parallel, green areas offer the potential to overcome many challenges that face growing/expanding cities but require the use of large amounts of natural resources such as natural topsoil and aggregates. In this work, various waste materials mixed with organic debris are tested for greening applications in urban environments as an alternative to the consumption of natural resources.

Materials and methods

Five combinations of artefacts were studied either as “growing material” (i.e. dedicated to plant growth) or “structural material” (as support for traffic). These constructed Technosols were studied in situ in lysimeters under two sets of contrasting climatic conditions at two sites in France (Angers, oceanic climate, and Homécourt semi-continental climate). They were planted with trees (Acer platanoides) and with ryegrass (Lolium perenne L.).

Results and discussion

Compared to natural soils, the constructed Technosols exhibited high porosities and highly saturated hydraulic conductivities (up to 0.76 m³ m^?3, and to 34.74 cm h^?1, respectively). The physical properties–i.e. macroporosity and microporosity–of these artificial soils revealed high water supply for plants, with available soil water ranging from 0.5 to 2.9 mm cm^?1. Tree and ryegrass roots were able to grow in the entire soil volume available in the lysimeters. Organic matter nature and soil pH conditions appeared to be the main drivers of plant development.

Conclusions

Constructed Technosols are suitable for vegetation growth and constitute a valuable alternative to the consumption of natural arable earth for urban greening applications, e.g. gardens, parks, and tree lines. Furthermore, they can provide high levels of relevant ecosystem functions in cities such as water retention and infiltration, plant settlement, carbon sequestration and even biodiversity habitats.

     

Effects of linear density and twist level on the mechanical properties of nylon 6.6 tyre cords

The performance of high tenacity nylon 6.6 tyre cords with different linear densities (dtex) was investigated by measuring some mechanical, structural and physical properties. The structural changes due to the dipping process were analyzed by differential scanning calorimetry and X-ray diffraction analysis. The breaking strengths were increased with the increasing linear densities, but decreased with twist level. As the linear density increases, shrinkage values of greige cords were increased. Shrinkage is mostly dependent on amorphous parts of the cords. Since amorphous parts of the dipped cords are lower than greige cords, shrinkage values for dipped cord were lower than that of greige cords. Adhesion values were increased with the increasing linear density and twist level. It has been observed that increasing of the twist levels explicitly improved the fatigue resistance in the cases 1400 and 1880 dtex cords. But, no significant changes were observed for 940 dtex cords. It has been found that cords with lower linear densities had better fatigue resistance than that of the cords with higher linear densities.     

Bromopyrrole Alkaloids as Lead Compounds against Protozoan Parasites

In the present study, 13 bromopyrrole alkaloids, including the oroidin analogs hymenidin (2), dispacamide B (3) and dispacamide D (4), stevensine (5) and spongiacidin B (6), their derivatives lacking the imidazole ring bromoaldisin (7), longamide B (8) and longamide A (9), the dimeric oroidin derivatives sceptrin (10) and dibromopalau’amine (11), and the non-oroidin bromopyrrolohomoarginin (12), manzacidin A (13), and agelongine (14), obtained from marine sponges belonging to Axinella and Agelas genera have been screened in vitro against four parasitic protozoa, i.e., two Trypanosoma species (T. brucei rhodesiense and T. cruzi), Leishmania donovani and Plasmodium falciparum (K1 strain, a chloroquine resistant strain), responsible of human diseases with high morbidity and, in the case of malaria, high mortality. Our results indicate longamide B (8) and dibromopalau’amine (11) to be promising trypanocidal and antileishmanial agents, while dispacamide B (3) and spongiacidin B (6) emerge as antimalarial lead compounds. In addition, evaluation of the activity of the test alkaloids (2–14) against three different enzymes (PfFabI, PfFabG, PfFabZ) involved in the de novo fatty acid biosynthesis pathway of P. falciparum (PfFAS-II) identified bromopyrrolohomoarginin (12) as a potent inhibitor of PfFabZ. The structural similarity within the series of tested molecules allowed us to draw some preliminary structure-activity relationships. Tests against the mammalian L6 cells revealed important clues on therapeutic index of the metabolites. This is the first detailed study on the antiprotozoal potential of marine bromopyrrole alkaloids.     

Phytophthora species associated with dieback of sweet chestnut in Western Turkey

Sweet chestnut (Castanea sativa) is an important tree species in the Marmara and Aegean regions of Turkey as these two regions produce the great majority of edible nuts, especially those used for marron glacé production. Chestnut forests and orchards in these regions showing severe dieback symptoms not associated with chestnut blight were investigated to determine the role of Phytophthora spp. in the decline syndrome. Soil samples were collected from around 108 symptomatic chestnut trees at 29 sites and Phytophthora spp. isolated using soil baiting technique and selective medium. Species isolated were identified by cultural characteristics and ITS sequencing. Phytophthora x cambivora was the dominant species detected in 13 sites, followed by P. cinnamomi (5 sites), P. plurivora (3 sites) and P. cryptogea (1 site). Phytophthora x cambivora was present in both regions, while P. cinnamomi was found only in the Marmara region in coastal areas around Istanbul. When inoculated at the stem bases of 3‐year‐old chestnut saplings, P. cinnamomi produced significantly longer necrotic lesions (7.8–12.0 cm) than P. x cambivora (2.6–6.3 cm) by 12 days after inoculation. Phytophthora plurivora was the least aggressive species causing only small lesions. Phytophthora cryptogea, which represents the first record on chestnut in Turkey, produced intermediate sized lesions in between P. x cambivora and P. plurivora. These results indicate that P. x cambivora and in some areas P. cinnamomi play major roles in the observed dieback of sweet chestnut in western Turkey.     

Effect of stocking density on growth performance of juvenile sea cucumber Holothuria tubulosa (Gmelin, 1788)

Stock density is one among the most important factors in aquaculture that directly influences the growth of organisms; however, there is limited information about the effects of stocking density on growth performance of sea cucumber Holothuria tubulosa (Gmelin, 1788) that has a commercial potential and represents a new species for aquaculture. In this study, we investigated the effect of stocking densities on the growth performance of juvenile H. tubulosa (40.3 ± 3.34 g) in laboratory conditions. Stocking densities were selected as 6, 15 and 30 ind m^?2 with total biomass 253.3 ± 0.18, 601.2 ± 0.11 and 1201.4 ± 0.15 g m^?2 respectively. We monitored the growth by wet weights and calculated the growth performance through weight gain, growth rate, specific growth rate, relative weight gain, coefficients of variation and survival rate during 8 weeks of research period. We found that individual mean weight gain in 6 ind m^?2 group was approximately 29.53 g while it was 3.03 g and ?4.36 g for 15 ind and 30 ind m^?2 groups respectively. Results have shown that the specific growth rate tends to decrease as the number of individuals in unit area increases. The final mean weight, growth rate, specific growth rate, relative weight gain and coefficients of variation were significantly different among treatment groups. In conclusion, a density of 6 ind m^?2 is recommended for stocking juvenile H. tubulosa under rearing conditions. Stocking density of 15 ind m^?2 is not favourable for long term as the growth rate is negligible where 30 ind m^?2 should be avoided in tank‐based rearing units.     

Acrylamide/potassium 3-sulfopropyl methacrylate/sodium alginate/bentonite hybrid hydrogels: Synthesis,characterization and its application in lauths violet removal from aqueous solutions

In this report, it was to investigate that the swelling and dye sorption properties of a series of novel hybrid composite hydrogel sorbent systems containing polysaccharide/clay polyelectrolyte based on acrylamide/potassium 3-sulfopropyl methacrylate and sodium alginate, and clay such as bentonite were synthesized with free radical solution polymerization by using ammonium persulfate/N,N,N’,N’-tetramethylethylenediamine as redox initiating pair in presence of poly(ethylene glycol) diacrylate as a crosslinker. Swelling experiments were performed in water at 25 °C, gravimetrically. The hydrogels, the semi-interpenetrating polymer networks, and the hybrid composite hydrogel systems that synthesized in this study have showed high water absorbency. Some swelling and diffusion properties were calculated, and they were discussed for the hybrid hydrogel systems prepared under various formulations. The equilibrium percentage swelling degree of highly swollen hybrid composite hydrogel systems ranges are 718-2055 %. FT-IR analysis and SEM technique were applied for characterization. For sorption of water-soluble cationic dye such as lauths violet into the hydrogel systems was studied by batch sorption technique at 25 °C. For equilibrium sorption studies, dye sorption percentage, dye uptake performance, and partition coefficient of the hydrogel systems have been investigated. The values of dye sorption percentage of the hydrogels were changed among 87.11-96.39 %. Consequently, the hydrogel systems developed in this study could serve as a potential device for water and dye sorbent.     

Application of Feature-Based Molecular Networking for Comparative Metabolomics and Targeted Isolation of Stereoisomers from Algicolous Fungi

Seaweed endophytic (algicolous) fungi are talented producers of bioactive natural products. We have previously isolated two strains of the endophytic fungus, Pyrenochaetopsis sp. FVE-001 and FVE-087, from the thalli of the brown alga Fucus vesiculosus. Initial chemical studies yielded four new decalinoylspirotetramic acid derivatives with antimelanoma activity, namely pyrenosetins A–C (1–3) from Pyrenochaetopsis sp. strain FVE-001, and pyrenosetin D (4) from strain FVE-087. In this study, we applied a comparative metabolomics study employing HRMS/MS based feature-based molecular networking (FB MN) on both Pyrenochaetopsis strains. A higher chemical capacity in production of decalin derivatives was observed in Pyrenochaetopsis sp. FVE-087. Notably, several decalins showed different retention times despite the same MS data and MS/MS fragmentation pattern with the previously isolated pyrenosetins, indicating they may be their stereoisomers. FB MN-based targeted isolation studies coupled with antimelanoma activity testing on the strain FVE-087 afforded two new stereoisomers, pyrenosetins E (5) and F (6). Extensive NMR spectroscopy including DFT computational studies, HR-ESIMS, and Mosher’s ester method were used in the structure elucidation of compounds 5 and 6. The 3’R,5’R stereochemistry determined for compound 6 was identical to that previously reported for pyrenosetin C (3), whose stereochemistry was revised as 3’S,5’R in this study. Pyrenosetin E (5) inhibited the growth of human malignant melanoma cells (A-375) with an IC₅₀ value of 40.9 μM, while 6 was inactive. This study points out significant variations in the chemical repertoire of two closely related fungal strains and the versatility of FB MN in identification and targeted isolation of stereoisomers. It also confirms that the little-known fungal genus Pyrenochaetopsis is a prolific source of complex decalinoylspirotetramic acid derivatives.     

The role of chicken IL-1β, IL-6 and TNF-α in the occurrence of amyloid arthropathy

In this study, the roles of IL-1β, IL-6 and TNF-α in amyloid arthropathic chickens with variable amounts (severe, moderate and mild) of amyloid accumulation were investigated. The presence and the levels of cytokines were evaluated in serum and in joint tissues by using ELISA and immunohistochemistry, respectively. One hundred brown layer chicks were allocated into four groups and intra-articular injections of Freund’s adjuvant were used to induce amyloid arthropathy in Groups II, III and IV. Vitamin A in group II, and methylprednisolone in Group IV were added to enhance and to reduce the severity of amyloidosis, respectively. At the end of the study, a positive correlation was observed among the incidence and severity of amyloidosis, the serum amyloid A levels and the IL-1β values both in the serum and tissues. Elevation in the tissue TNF-α levels in parallel with the severity of amyloidosis has also been noted. As a conclusion, IL-1β appears to play an important role in avian AA amyloidosis either alone or in combination with TNF-α. Further investigation is needed for understanding the role of the pro-inflammatory cytokines in avian AA amyloidosis.     

Fertility in Dairy Cows After Artificial Insemination Using Sex‐Sorted Sperm or Conventional Semen

The aim of this study was to compare pregnancy per artificial insemination (P/AI) after timed AI with sex‐sorted sperm (SS) or conventional semen (CS) in lactating dairy cows. Cyclic cows (n = 302) were synchronized by Ovsynch and randomly assigned into two groups at the time of AI. Cows with a follicle size between 12 and 18 mm and clear vaginal discharge at the time of AI were inseminated with either frozen‐thawed SS (n = 148) or CS (n = 154) of the same bull. A shallow uterine insemination was performed into the uterine horn ipsilateral to the side of probable impending ovulation. Pregnancy per AI on Day 31 tended (p = 0.09) to be less for SS (31.8%) than CS (40.9%). Similarly, P/AI on Day 62 was less (p = 0.01) for cows inseminated with SS (25.7%) compared with CS (39.0%). The increased difference in fertility between treatments from Days 31 to 62 was caused by the greater (p = 0.02) pregnancy loss for cows receiving SS (19.2%) than CS (4.8%). Cow parity (p = 0.02) and season (p < 0.01) when AI was performed were additional factors affecting fertility. Primiparous cows had greater P/AI than multiparous cows both on Day 31 (41.7% vs 25.0% in SS and 53.0% vs 31.8% in CS groups) and on Day 62 (33.3% vs 20.5% in SS and 48.5% vs 31.8% in CS groups). During the hot season of the year, P/AI on Day 31 was reduced (p = 0.01) in the SS group (19.6%) when compared with the rates during the cool season (38.1%). In conclusion, sex‐sorted sperm produced lower fertility results compared to conventional semen even after using some selection criteria to select most fertile cows.