The activity against leukocyte eicosanoid generation of essential oil and polar fractions of Adesmia boronioides Hook.f

Insecticidal Activity of Four Essential Oils Extracted from Chilean Patagonian Plants as Potential Organic Pesticides

Patagonia is a geographical area characterized by a wide plant biodiversity. Several native plant species are traditionally used in medicine by the local population and demonstrated to be sources of biologically active compounds. Due to the massive need for green and sustainable pesticides, this study was conducted to evaluate the insecticidal activity of essential oils (EOs) from understudied plants growing in this propitious area. Ciprés (Pilgerodendron uviferum), tepa (Laureliopsis philippiana), canelo (Drimys winteri), and paramela (Adesmia boronioides) EOs were extracted through steam distillation, and their compositions were analyzed through GC−MS analysis. EO contact toxicity against Musca domestica L., Spodoptera littoralis (Boisd.), and Culex quinquefasciatus Say was then evaluated. As a general trend, EOs performed better on housefly males over females. Ciprés EO showed the highest insecticidal efficacy. The LD50(90) values were 68.6 (183.7) and 11.3 (75.1) µg adult−1 on housefly females and males, respectively. All EOs were effective against S. littoralis larvae; LD50 values were 33.2−66.7 µg larva−1, and tepa EO was the most effective in terms of LD90 (i.e., <100 µg larva−1). Canelo, tepa, and paramela EOs were highly effective on C. quinquefasciatus larvae, with LC50 values < 100 µL L−1. Again, tepa EO achieved LD90 < 100 µL L−1. This EO was characterized by safrole (43.1%), linalool (27.9%), and methyl eugenol (6.9%) as major constituents. Overall, Patagonian native plant EOs can represent a valid resource for local stakeholders, to develop effective insecticides for pest and vector management, pending a proper focus on their formulation and nontarget effects.

Activity of Adesmia boronioides resinous exudate against phytopathogenic bacteria

Resinous exudate obtained from the aerial parts of Adesmia boronioides Hook.f. were evaluated to determine anti-phytopathogenic effects. Briefly, resinous exudate was obtained by dipping fresh plant material in dichloromethane; chemical composition was determined by GC-MS; and minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) were evaluated against four phytopathogenic bacteria. Resinous exudate yield was 8.5% (resin/fresh plant), of which esquel-6-en-9-one (14.25%), esquel-7-en-9-one (5.86%), and veratric acid (2.59%) were the effective antibacterial compounds. Tested against Pectobacterium carotovorum subsp. carotovora, Erwinia amylovora, Bacillus subtilis, and Pseudomonas syringae, MICs and MBCs ranged from 16 to 128 µg/mL and 32-256 µg/mL, respectively. These results provide initial evidence that resinous bush A. boronioides is a new and alternative source of substances with agricultural interest.

Antioxidant and anti-inflammatory activities of essential oils: a short review

Essential oils are complex mixtures isolated from aromatic plants which may possess antioxidant and anti-inflammatory activities of interest in thye food and cosmetic industries as well as in the human health field. In this work, a review was done on the most recent publications concerning their antioxidant and anti-inflammatory activities. At the same time a survey of the methods generally used for the evaluation of antioxidant activity and some of the mechanisms involved in the anti-inflammatory activities of essential oils are also reported.

In Vitro effect of D-004, a lipid extract of the ground fruits of the Cuban royal palm (Roystonea regia), on rat microsomal lipid peroxidation

D-004 is a lipid extract of the fruits of the Cuban royal palm (Roystonea regia) containing a mixture of saturated fatty acids. D-004 inhibits prostate hyperplasia (PH) induced with testosterone, in rodents. Since fatty acids inhibit lipid peroxidation (LP), this study investigated whether D-004 prevents in vitro LP. D-004 (0.9-1000 microg/mL) markedly and dose-dependently inhibited in vitro iron-induced LP in native brain and liver microsomes. D-004 showed hydroxyl radical scavenging activity, which could explain partially its antioxidant effect on microsomal iron-induced LP, but it was unable to scavenge superoxide and ABTS radicals, indicating a limited radical scavenging activity. Also, D-004 inhibited CCl4-mediated LP in active liver microsomes through a decreased generation of radical species rather than a radical trapping action on CCl(4)-derived radical species. D-004 also inhibited lipooxygenase (LOX) and cyclooxygenase (COX) activities, and the generation of protein-associated carbonyl groups after LP. Since increased oxidative stress has been linked to PH, the antioxidant effect of D-004 shown here could contribute to explaining its beneficial effects on T-induced PH in rodents. Nevertheless, this study shows only in vitro results. Further studies should investigate whether D-004 also exhibits antioxidant effects in vivo.

Lipoxygenase inhibitors from natural plant sources. Part 1: Medicinal plants with inhibitory activity on arachidonate 5-lipoxygenase and 5-lipoxygenase[sol ]cyclooxygenase

Arachidonate 5-lipoxygenase is the key enzyme in leukotriene biosynthesis and catalyses the initial steps in the conversion of arachidonic acid to biologically active leukotrienes. Leukotrienes are considered as potent mediators of inflammatory and allergic reactions and regarding their pro-inflammatory properties the inhibition of 5-lipoxygenase pathway is considered to be interesting in the treatment of a variety of inflammatory diseases. Besides 5-lipoxygenase inhibitors, drugs able to block the 5-lipoxygenase as well as the cyclooxygenase metabolic pathway are also of therapeutic value. A potential source for new 5-lipoxygenase inhibitors is undoubtedly provided by the abundance of medicinal plants used in traditional medicine. The present review article reports the results from a comprehensive literature search of plants that have been tested for 5-lipoxygenase inhibitory activity over the past 15 years. The obtained information is summarized in a tabular format and promising plant species and chemical classes of compounds are presented. Relevant in vitro tests are also described in this article.