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Chemical modification of starch from the chayote root (Sechium edule Jacq) is carried out with lauric acid and acetic anhydride. The modified starch is characterized by Fourier‐transform infrared spectrometry (FTIR), X‐ray diffraction (XRD), and Differential Scanning Calorimetry (DSC) and used to formulate edible films. The developed edible films are characterized based on their physicochemical and mechanical properties. The physicochemical and functional properties of starch are affected by the incorporation of the acyl and acetyl group. Both starches exhibit a significant decrease in solubility. Starch modified by the incorporation of the acyl group (lauroyl) has higher thermal stability than starch modified by the incorporation of the acetyl group. The first shows an increase in emulsifying and foaming capacity, as well as water‐ and oil‐retention capacity, while the second exhibits adequate edible film‐forming properties. The edible films develop with modified starch with acetyl group has a homogeneous surface and exhibit a higher percentage of elongation at break when they are stored at a water activity of 0.561. In accordance with the above, it is concluded that the chayote root starch modified has physicochemical and functional properties that indicate their potential utility in the food industry. [ABSTRACT FROM AUTHOR]

The objective of the work was preparation and characterization of novel biomaterial produced by modification of the mucilage of nopal acylated with lauric acid and to increase the knowledge and better understanding about its relationship with the techno-functional properties. Hydrophobic mucilage was obtained, and its structural features were elucidated and confirmed by FTIR, X-ray diffraction, and 1H NMR. Modified mucilage exhibited significantly different physicochemical and functional properties compared to native mucilage. The modified mucilage was less soluble (15.65–16.99%), had lower water holding capacity (5.59–13.45 g/g), and exhibited greater oil holding capacity (4.47 g/g) than the native mucilage; in addition, it showed a surface tension of 57.2 mN/m, which correspond to a critical micellar concentration of 0.023 mg/mL. Acylated mucilage exhibited the highest foaming capacity (124.16%) at pH 10. This study demonstrates that the acylation of mucilage with lauric acid modifies the physicochemical and functional properties of mucilage from Opuntia ficus-indica and suggests applications in the food, pharmaceutical, or packaging industries. [ABSTRACT FROM AUTHOR]

Avocado pulp is highly susceptible to deterioration. The objective of this work was to evaluate the physicochemical and antioxidant properties of avocado powder with and without ginger extract. Ginger extract and inlet temperature at 160°C improved antioxidant properties measured by DPPH inhibition (62.51%), FRAP (118.44 mg TE/g powder), and ABTS (53.35 mg TE/g powder), while the use of a higher spray‐drying temperature (180°C) adversely affected color parameters and flow properties. The retention of total polyphenols in the powder during the spray‐drying process varied from 64.46% to 77.44%. Changes in color and antioxidant activity showed first‐order kinetics and the powders exhibited greater stability at a lower water activity of storage. The addition of ginger extract, a drying temperature of 160°C, and lower water activity favor the stability of avocado powder during storage. This powder can be used as a functional ingredient in various food, pharmaceutical, or cosmetic formulations. Novelty impact statement: This work demonstrated that the addition of ginger extract rich in natural antioxidants improves the physicochemical and antioxidant stability of avocado pulp powders using maltodextrin as a carrier during the drying process and during storage at different storage temperatures. This research impacts on the knowledge that exists to date about the preparation of avocado powder added with ginger, their properties, and potential use in food, pharmaceutical, biotechnological, and cosmetic applications. [ABSTRACT FROM AUTHOR]

The effect of chemical modification of fractions of native agave fructans (NAF), high performance (HPAF), and a high degree of polymerization (HDPAF) by lauroylation, acetylation, and succinylation reactions on their prebiotic activity, antibacterial properties were evaluated and survival of L. paracasei in a simulated gastrointestinal system. The characterization of the reactions was confirmed by NMR and FTIR. The lauroylated and succinylated fructan fractions showed higher antibacterial activity against pathogenic bacteria such as Escherichia coli, Enterococcus faecalis and Staphylococcus aureus than the unmodified ones. Analyses with L. paracasei showed that the acetylated fructan fractions had a greater prebiotic effect, and simulated gastrointestinal tests demonstrated that the acetylated and succinylated fractions favored the survival of L. paracasei during the gastrointestinal phase. The effect of modifying the agave fructans fractions on the evaluated properties depended on the structure, size, and polarity of each incorporated functional group, as well as the degree of polymerization and substitution of each fraction. These results show that the chemical modification of the fructan fractions analyzed improves their functional properties, offering an alternative in the food and pharmaceutical industry. [ABSTRACT FROM AUTHOR]

5-Lipoxygenase (5-LOX) converts arachidonic acid to lipidic inflammatory mediators such as leukotrienes (LTs). In diseases such as asthma, LTs contribute to a physiopathology that could be reverted by blocking 5-LOX. Natural products with anti-inflammatory potential such as ginger have been used as nutraceuticals since ancient times. 6-Gingerol and 6-shogaol are the most abundant compounds in the ginger rhizome; they possess anti-inflammatory, antioxidant, and chemopreventive properties. In the present study, 6-gingerol and 6-shogaol structures were analyzed and compared with two commercial 5-LOX inhibitors (zileuton and atreleuton) and with other inhibitor candidates (3f, NDGA, CP 209, caffeic acid, and caffeic acid phenethyl ester (CAPE)). The pharmacokinetics and toxicological properties of 6-gingerol, 6-shogaol, and the other compounds were evaluated. Targeted molecular coupling was performed to identify the optimal catalytic pocket for 5-LOX inhibition. The results showed that 6-gingerol and 6-shogaol follow all of the recommended pharmacokinetic parameters. These compounds could be inhibitors of 5-LOX because they present specific interactions with the residues involved in molecular inhibition. The current study demonstrated the potential of 6-gingerol and 6-shogaol as anti-inflammatory agents that inhibit 5-LOX, as they present a high level of performance in the toxicological analysis and could be catabolized by the cytochrome p450 enzymatic complex; however, 6-gingerol was superior in safety compared to 6-shogaol. [ABSTRACT FROM AUTHOR]

This article discusses the synthesis of new C2 bishydroxamic acid (BHA) ligands and their use in asymmetric epoxidation reactions. Previous studies have focused on chiral BHA ligands, but achieving consistent high enantioselectivity has been challenging. The article presents the synthesis of two novel phenyl ring-centered C2 symmetric chiral BHA ligands and their application in asymmetric epoxidation reactions. The researchers optimized reaction conditions and found that acetonitrile was the ideal solvent. However, they encountered challenges in improving the conversion of the reaction and are conducting further investigations. The document provides detailed information about the synthesis and characterization of various compounds, including purification methods and NMR and HRMS data. [Extracted from the article]

Throughout human history, bacteria and fungi have caused infections that are difficult to combat. For this reason, countless research groups have developed novel compounds to solve this problem. Thiazole and benzothiazole are present in different structures with interesting biological effects and are used to develop new effective antimicrobial agents. Moreover, nitrogen atoms that are present in this heterocycle allow for coordination with various metals, forming metal complexes that enhance the biological activity of organic ligands that are often used as commercial drugs. This bibliographical review summarizes the copper complexes that use thiazole and benzothiazole as ligands and that report efficient antimicrobial activity against different bacteria and fungi. [ABSTRACT FROM AUTHOR]

Abstract: The efficient preparation of both enantiomers of dimethyl δ,β-dihydroxyethylphosphonate 2 has been achieved from salicylaldehyde as a starting material, through the resolution of dimethyl (±)-2-(2-O-benzylphenyl)-2-hydroxyethylphosphonate 4 using (S)-methoxyphenylacetic acid (MPA). The absolute configuration was assigned by the Dale and Mosher approach using extended Newman projections and ab initio calculations. [Copyright &y& Elsevier]

Coumarins are bioactive substances of the benzo-α-pyrone family, which have shown antioxidant, antiviral, anti-inflammatory and antitumor activities, among others. 7-Hydroxycoumarin and 6,7-dihydroxycoumarin (esculetin) are two coumarin derivatives that have been reported to exhibit antitumor activity, but the action mechanism underlying this activity remains unknown. In this work, to elucidate this mechanism, a theoretical study of the local and global electronic reactivity properties of a series of hydroxylated and dihydroxylated coumarin derivatives with possible antitumor action is performed using Density Functional Theory in aqueous solution. The substitution by one or two hydroxyl groups in the benzene ring of coumarin produces better charge-donor than charge-acceptor compounds. All the studied compounds are generally stable in water and exhibit permanent polarization in the solvent. With one hydroxyl substitution, 7-hydroxycoumarin is the most polar and polarizable derivative, whereas 5,7-dihydroxycoumarin is the most polar and polarizable compound with two hydroxyl substitutions. 5,7-Dihydroxycoumarin is suggested to possess antitumor activity. © 2016 Wiley Periodicals, Inc. [ABSTRACT FROM AUTHOR]

Abstract: Herein we report a practical and efficient method for the synthesis of optically active 2,4-disubstituted oxazolines (S)-1a–h in good to excellent yields. The target compounds were prepared in good yield through the Horner–Wadsworth–Emmons reaction of β-phosphonoamide 3 bearing l-phenylalaninol with commercially available aryl aldehydes followed by the cyclodehydration of the corresponding N-(cinnamoyl)-(S)-phenylalaninol derivatives (S)-2a–h. Additionally, the cyclodehydration of β-phosphonoamide (S)-3 followed by the Horner–Wadsworth–Emmons reaction of β-phosphono-oxazoline (S)-4 with aryl aldehydes also gave the 2,4-disubstituted oxazolines (S)-1a–h. [Copyright &y& Elsevier]

Phytoremediation is an ecologically sound biotechnology directed to cleaning up contaminated soils. The study of tree species to treat petroleum contaminated soils is scarce; moreover, the combination of phytoremediation with bioaugmentation and biostimulation processes is also limited. Thus, this work evaluated the effects of the inoculation of Glomus intraradices, a bacterial consortium (M2BOS1-R2 and M2BOSI-F4) and Trichoderma viride, on the growth of Casuarina equisetifolia, fertilized with Floranid® or Triple 17, when sown in a diesel-contaminated soil (7 500mg/kg). The factorial experiment 2x5x3 included 30 treatments with 10 replicates in a completely randomized design under greenhouse conditions for 120 days. Diesel significantly diminished plant height, total biomass, and plant index quality (PIQ). Glomus or bacterial consortium significantly increased plant height, total biomass and PIQ when compared to the inoculation of the three microorganisms or to the control. Floranid had negative effects on plant growth and PIQ at diesel contamination. Fertilization with Triple 17 combined with the three microorganisms stimulated plant growth in the absence of diesel, whereas in the presence of this contaminant the treatments combining Triple 17 with the bacterial consortium or with Trichoderma had better plant growth and PIQ. Mycorrhizal colonization was inhibited due to diesel contamination, and especially when Floranid was applied. The fertilizer Triple 17 (biostimulation) combined with the beneficial microorganisms (bioaugmentation) improved growth responses of C. equisetifolia in diesel-contaminated soil. [ABSTRACT FROM AUTHOR]

A laboratory screening study following USEPA SW-846 test methods allowed the detection of organic compounds in the aquatic habitat of the Neotropical river otter (Lontra longicaudis annectens), in the Alvarado Lagoon System, Veracruz, Mexico. The compounds detected included 2-chlorocyclohexanol, phenylethylene glycol, benzophenone, ethanol-2-butoxyphosphate, styrene, p-xylene, ethylbenzene, trans-1,2- cyclohexanediol, di-2-ethylhexyl phthalate, benzeneacetaldehyde, hexadecane, tetracosane, docosane, triacontane, sitosterol, hexadecanoic acid, 1-eicosanol, chlorobenzene, and phosphorothioic acid trimethyl ester. Literature review showed a lack of data on the compounds' potential effects on wildlife, although some of them could be considered harmful to the otters and their prey. The different compounds detected needs follow-up. [ABSTRACT FROM AUTHOR]

Abstract: Chiral phosphonoacetamides bearing (S)-(α-methylbenzyl)benzylamine, (S,S)-bis(α-methylbenzyl)amine, l-phenylglycine methyl ester and l-phenylglycinol were easily prepared in good yield by means of the Michaelis–Arbuzov reaction of chiral bromoacetamides obtained in quantitative yield, with trimethyl phosphite, which under Horner–Wadsworth–Emmons conditions with several aryl and alkyl aldehydes under Masamune–Roush procedure using LiCl and DBU in THF or toluene gave the corresponding chiral α,β-unsaturated amides. The present procedure is a convenient and efficient methodology for the preparation of phosphonoacetamides and chiral α,β-unsaturated amides in high E-selectivity. [Copyright &y& Elsevier]

Abstract: The present study was aimed to determine whether the urine from donor rats, which were physically stressed (UD-PS) by unavoidable electric footshocks, produces despair in receptor partner rats (RP) in the long-term. For each trial, an RP rat was placed during 10 min once per day for 21 days in a small non-movement-restricting cage impregnated with the urine collected from a UD-PS rat. Control rats, free of stimulation, maintained their locomotion and immobility scores at basal values throughout the 21-day test. After 21 days of stressing experience [F(2,90)=15.22, P <0.0001] locomotion significantly increased in RP rats (r =0.938, P <0.01), whereas in the UD-PS group locomotion decreased (r =−0.606, P <0.05). The RP and UD-PS groups displayed the longest time of immobility [F(2,90)=8.83, P <0.001] in the forced-swim test (RP, r =0.886, P <0.05; UD-PS, r =0.962, P <0.001) compared with the control group (r =−0.307, NS). We conclude that the RP became similarly despaired as the UD-PS group through the action of 2-heptanone, a ketonic compound identified in UD-PS urine by HS-GC/MS techniques. This ketone was found to be increased [F(2,15)=3.50, P <0.05] from the 1st day of unavoidable electric footshocks, and to induce despair, an effect reverted [F(2,21)=16.5, P <0.0001] by imipramine (5.0 mg/kg) in another group of rats. [Copyright &y& Elsevier]

We analyzed the role of cuticular compounds in sexual recognition of the carrion ball-roller scarab, Canthon cyanellus cyanellus (LeConte) (Coleoptera: Scarabaeidae). Males rolled food balls with freeze-killed females on them as though the females were alive. Acceptance of female cadavers was low when they were washed with solvents and increased significantly when the solvent extract was reapplied to the cadavers. Acceptance of female cadavers by males was significantly higher than that of male cadavers by females. Male cadavers washed with solvent and impregnated with female cuticular compounds were accepted by males as though they were frozen or living females. Similarly, extracted female cadavers impregnated with male cuticular compounds were accepted by females. These results suggest that C. c. cyanellus males recognize females by their cuticular compounds, whereas females use a combination of cuticular compounds and other unknown cues to recognize males. [ABSTRACT FROM AUTHOR]

Six tris(aryloxy)phosphorothionates substituted in the para position of the aromatic rings were synthesized and studied by 31P NMR, X-ray diffraction techniques and ab initio calculations at a RHF/6-31G** level of theory, in order to find the main structural factors associated with the δ31P in these compounds. As the electron-withdrawing (EW) ability of the substituents was increased, an ‘abnormal’ shielding effect on δ31P of the arylphosphorothionates was observed. The analyses of the geometrical properties obtained through both experimental and theoretical methods showed that a propeller-type conformation is preferred for the arylphosphorothionates, except in the case of the tris(O-4-methylphenyl)phosphorothionate, since one of the aromatic rings is not rotated in the same direction as the other two in the solid state. The main features associated with the δ31P NMR of compounds 1–6 were a decrease of the averaged O–P–O angle and mainly the shortening of the P＝S bond length, which is consistent with an increase of the thiophosphoryl bond order as δ31P values go upfield. On the other hand, comparison of the experimental and calculated bond lengths and bond angles involving α bonded atoms to phosphorus of the six compounds suggested that stereoelectronic interactions of the type nπO-σ*O-σ*, and nπS-σ*P-OAr and nπS-σ*P-OAr and nπS σ*P-OAr could be present in the arylphosphorothionates 1–6 . [Copyright &y& Elsevier]

Abstract: The sensorial stimulation arising from a physically stressed (PS) subject may produce emotional stress in a witnessing partner (WP). Both members of the pair develop functional changes. We tested changes in locomotor activity (crossing) and in the defensive burying test in WP, and PS adult male Wistar rats having been submitted to a single 10min session in a two-compartment cage. During this session, the WP rats received auditory and olfactory stimulation coming from a PS pair submitted to unavoidable electric footshocks (1mA, dc, 0.5s, 0.5c/s, 10min). This experiment was replicated in other groups pre-treated with vehicle or diazepam, and their urine was collected and analyzed by the static Head-Space and Gas Chromatography–Mass Spectrometry (HS-GC/MS) techniques. The WP group displayed a significantly higher crossing [F (2,45) =4.31, P <0.01] and more cumulative burying time [F (2,22) =4.73, P <0.01] than the control or PS groups. Diazepam (1mg/kg) reverted these changes. Our results indicate that the conspecific sensorial communication coming from the PS group produces anxiety probably mediated by 2-heptanone, since the HS-GC/MS analyses showed the highest amount of 2-heptanone in the urine from the PS group [F (2,42) =5.17, P <0.009]. [Copyright &y& Elsevier]

An efficient synthesis of both enantiomers of dimethyl δ-amino-β-hydroxyethylphosphonate 6 has been achieved starting from anthranilic acid, through the resolution of dimethyl (±)-2-(2-N,N-dibenzylaminophenyl)-2-hydroxyethylphosphonate 9 with (S)-O-methylmandelic acid. The absolute configuration of the enantiomers 9 was assigned by the Dale and Mosher approach using the extended Newman projections and molecular mechanics. [Copyright &y& Elsevier]

This study identified microbial functional groups like total culturable bacteria, potential N2-fixing free living bacteria, N2-fixing hydrocarbonoclastic bacteria, N-assimilating hydrocarbonoclastic bacteria, total fungi, actinobacteria, P-solubilizers, lipolytic microorganisms, and starch, cellulose, pectin and protein degrading microorganisms, isolated from the rhizosphere of four species of mangroves (Red, Black, White, and Button) from the natural protected area at the Terminos Lagoon, Campeche, México. Overall, microbial populations showed significant differences (P < 0.05) among the four mangrove species. The rhizosphere of White mangrove showed better chemical and textural soil properties, and harbored the highest microbial populations when compared to the remaining mangrove species. The principal component analysis indicated that two components accounted the 85.3% of the total variation. The most significant textural and chemical soil properties were the major components, CP1 (organic matter and total organic carbon) and CP2 (sand and clay). Microbial populations correlated (P < 0.05, Pearson coefficient) with sand and clay particles, and with some soil chemical properties such as organic matter. The total nitrogen and organic carbon significantly correlated with cellulose degraders, while phosphorus with N2-fixing bacteria, total fungi, and with pectin and starch degraders. [ABSTRACT FROM AUTHOR]