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Climate change is among the main causes of alterations in natural ecosystems, generating major impacts on native vegetation. Drought is considered one of the main threats to ecosystems under global climate change since it limits growth and the mobilization of carbohydrates, alters the photosynthetic rate, decreases productivity, and can cause higher rates of plant mortality. Studies have been using species of the fungus Trichoderma in the inoculation of plants under conditions of water stress, such as drought, however, its use in native tree plants is still scarce. Considering that Inga laurina (Sw.) Willd (Fabaceae) is a tree species found preferentially in humid or flooded regions and can be used in the recovery of degraded areas, the aim is to analyze the performance of young plants of I. laurina, inoculated and not inoculated with Trichoderma harzianum and kept in conditions of moderate drought and in pot capacity. After 21 days, we evaluated the length of the aerial part and root, the fresh and dry mass of the root, stem, and leaves, the number of leaves and the diameter of the collar, the total soluble carbohydrate content of the leaves and roots and the photosynthetic pigments in the leaves of the plants from each treatment. The results were statistically analyzed using the GraphPrim 8.0 statistical program. Plants kept in moderate drought, whether inoculated or not, showed no significant difference in terms of growth parameters. The chlorophyll a, chlorophyll b, total chlorophyll, and total carotenoid contents were lower in the plants under moderate drought as compared to the non-inoculated control plants, while the chlorophyll a/b ratio was higher in the inoculated plants. The content of total soluble carbohydrates was higher in the leaves of plants kept in moderate drought, with no significant difference observed in the roots of plants kept in the different treatments. When comparing leaves and roots for each treatment, there was a higher total soluble carbohydrate content in the roots, regardless of the treatment. Overall, there was a positive effect of T. harzianum in promoting growth and protecting I. laurina; the inoculated plants performed similarly to the plants in the control condition.

Intense and constant exposure to UVB radiation can lead to inflammation and oxidative stress, which are associated with many cutaneous disorders, including photoaging and skin cancer. Antioxidant plant materials that are rich in polyphenols, such as the ethyl acetate fraction (EAF) from Eugenia hiemalis leaves, and phenolic compounds represent a promising approach to protect the skin against UVB-induced damage. The present study evaluated the photochemoprotective potential of the EAF and its 2,6-di-O-galloylarbutin (1) isolate. The EAF and the phenolic antioxidant (1) reduced UVB-induced L929 fibroblast death. The EAF prevented UVB-induced damage in fibroblasts by inhibiting the intracellular production of reactive oxygen species and lipid peroxidation, especially in pretreated cells. Topical treatment with an emulsion with 1% EAF prevented/attenuated UVB-induced inflammation and oxidative stress in the skin in hairless mice by controlling the increase in myeloperoxidase activity, reducing superoxide anion production, maintaining radical-scavenging ability and ferric reducing power, and controlling the depletion of reduced glutathione and catalase levels. The EAF also inhibited the increase in epidermal thickness, mast cell infiltration, the number of sunburn cells and collagen fiber destruction that were triggered by UVB. The in vitro and in vivo results indicated that the EAF is a bioactive agent that is able to protect the skin against the harmful effects of UVB., (© 2021 American Society for Photobiology.)

The effects on the viability of promastigote and amastigote forms of Leishmania (Leishmania) amazonensis and citotoxicity in J774.A1 macrophages of ethanolic extract, fractions and isolated compounds that were obtained from the leaves of Nectandra cuspidata were determined. The total phenolics content (TP) and antioxidant activity were assessed using different assays. The ethyl acetate fraction (EAF) had the best antiproliferative activity (amastigote IC 50 : 4.42 ± 0.60 μg/mL, promastigote IC 50 : 33.33 ± 0.78) and presented no cytotoxicity at the highest concentration tested (1000 μg/mL). The EAF also had the greatest antioxidant capacity, which was comparable to butylated hydroxytoluene and quercetin (DPPH IC 50 6.54 ± 0.10 μg/mL, ABTS 4.75 ± 0.11 mmol ET/g; FRAP 2.37 ± 0.03 mmol ET/g; ORAC = 33.52 ± 1.99 mmol ET/g; TP 387.11 ± 0.25 mg GAE/g). Vitexin, epicatechin and isovitexin isolated from EAF contribute to both activities.

Rhipicephalus (Boophilus) microplus is one of the most important ectoparasites in cattle breeding worldwide, causing direct and indirect losses to animals and producers. Chemical acaricides are utilized in the control of cattle tick and the increase in the development of resistance by ectoparasites makes new alternative necessary. Therefore, research studies have been carried out using bioactive molecules that are quickly degraded and that reduce poisoning to appliers and non-target organisms, environmental contamination and development of resistance. Thus, this study aimed to isolate piperovatine from the roots of Piper corcovadensis, a native species to Brazil, and to evaluate the larvicidal activity against Rhipicephalus (Boophilus) microplus by larval packet test and in ex situ in an open environment. Piperovatine was isolated by classical column chromatography, and identified by 1 H and 13 C NMR. The lethal concentration (LC) of piperovatine that killed 50% (LC 50 ) and 99% (LC 99 ) of the larvae was determined by Probit analysis. The results indicated LC 50 5.17 and LC 99 25.41 μg/mL. LC 99 was tested in ex situ in an open environment, and an efficiency of 96.63% was found, indicating that piperovatine kept the larvicidal action determined in in vitro test and in open environment. Therefore, this study shows new perspectives to develop products that can be applied in natural conditions to control this ectoparasite., (Copyright © 2018 Elsevier B.V. All rights reserved.)

This work describes the preliminary evaluation of cytotoxic, antimicrobial, molluscicidal, antioxidant and anticholinesterase activities from leaf (LECF) and stem bark alcoholic extracts (BECF) of the species Croton floribundus Spreng. (Euphorbiaceae), popularly known as capixingui or tapixingui. BECF presented significant toxicity (LC50 = 89.6 μg/ml) in the Artemia salina Leach, 1819 (Crustacea: Branchiopoda) bioassay, whereas LECF did not show activity (LC50 > 1000 μg/ml). From DPPH method, the values of IC50 for the LECF and BECF were 61.2 μg/ml and 62.2 μg/ml, respectively, showing that C. floribundus has an expressive antioxidant activity. Antimicrobial susceptibility was evaluated by microdilution technique and only BECF was active against Staphylococcus aureus (MIC = 39.6 μg/ml). The extracts did not present molluscicidal activity against snail Biomphalaria glabrata Say, 1818 (Gastropoda: Planorbidae). Both extracts revealed the presence of several components with an inhibiting capacity of acetylcholinesterase enzyme on the bioautographic assay. C. floribundus showed to be a promising species considering that it exhibited good biological activity in the most assays performed.

The total phenolic content (TP) and antioxidant activity of the ethanolic extract and fractions that were obtained from the leaves of Nectandra hihua were assessed using different methods. The ethanolic extract (EE) and ethyl acetate fraction (EAF) had the best antioxidant capacity, which was comparable to butylated hydroxytoluene and quercetin (ABTS + 2.55 ± 0.06, 3.54 ± 0.03 mmol TE/g; DPPH IC 50 10.27 ± 0.05, 9.88 ± 0.02 μg/mL; FRAP 2.17 ± 0.08, 2.38 ± 0.04 mmol TE/g; ORAC 5.16 ± 0.08, 5.35 ± 0.07 mmol TE/g; TP 568.05 ± 18.15, 397.20 ± 17.88 mg GAE/g, respectively). The cytoprotective effect, reactive oxygen species (ROS) and lipid peroxidation inhibitions on L929 fibroblasts irradiated with UVB (600 mJ/cm 2 ) in pre- and post-treatments with EE and EAF were determined. These plant materials demonstrated high ROS scavenging activity and lipid peroxidation inhibition on L929 fibroblasts in both treatments, especially with pre-treatment (EE 38.47 ± 1.95% and EAF 40.20 ± 4.5% inhibition of ROS production, and EE 39.03 ± 3.33% and EAF 41.67 ± 7.6% of lipid peroxidation inhibition), indicating the best cytoprotection with pre-treatment (13.52 ± 1.66% and 13.34 ± 2.61% increases in cell viability). The antioxidant flavonoids quercitrin, avicularin, juglalin, afzelin and astragalin were isolated from EAF. The results obtained indicate that EE and EAF present photodamage attenuating potential against UVB-induced oxidative stress and can be useful as a starting point for developing dermatological products to prevent oxidative skin damage., (Copyright © 2018 Elsevier B.V. All rights reserved.)