Cyperus (Cyperus esculentus L.): A Review of Its Compositions, Medical Efficacy, Antibacterial Activity and Allelopathic Potentials.

Cyperus (Cyperus esculentus L.) is an edible perennial grass-like plant, which propagates exclusively with underground tubers. Its tubers are rich in starch (20-30%), fat (25-35%), sugar (10-20%), protein (10-15%) and dietary fiber (8-9%). In addition, the tubers also contain alkaloids, organic acids, vitamins (C and E), steroids, terpenoids and other active components. The contents of oleic acid and linoleic acid in Cyperus oil are very high, which have important medicinal value and health-promoting properties. Most of the extracts from the tubers, stems and leaves of Cyperus have allelopathic potential and antibacterial, antioxidant and insecticidal activities. In recent years, the planting area of Cyperus has increased significantly all over the world, especially in China and some other countries. This paper presents the current status of Cyperus and the recent trend in research in this area. Published reports on its nutritional contents, active ingredients, medicinal efficacy, antibacterial activity and allelopathic potential were also reviewed.

Toxicity of Piper aduncum (Piperaceae) Essential Oil Against Euschistus heros (F.) (Hemiptera: Pentatomidae) and Non-Effect on Egg Parasitoids.

Plant essential oils have been recognized as significant natural resources for insecticides. Herein, we have assessed the toxicity of the essential oil of Piper aduncum (Piperaceae) against Euschistus heros (F.) (Hemiptera: Pentatomidae), a key soybean pest in Neotropical America. In addition, we have assessed its effect on the performance of egg parasitoids. The essential oil was obtained from the leaves of P. aduncum via hydrodistillation. Subsequently, bioassays of the concentration response to eggs (contact and immersion methods), nymphs, and adults (topical application) were conducted, to assess the lethal effects on the stink bug. We also evaluated the performance of parasitism and adult emergence of egg parasitoids, when the host eggs were treated with essential oil. In the egg bioassay, both exposure methods were efficient for unviable eggs (immersion LC50 = 15.64 mg mL-1; contact LC50 = 21.29 mg mL-1), with the highlight on the immersion method. The bioassay with nymphs indicated a higher toxicity of essential oil, with lower concentrations (LC50 = 11.37 mg mL-1) being required to cause the death of insects. For adults, a reduction in survival of insects was observed, and consequently, there was a reduction in the number of individuals in the next generation. Although the essential oil was toxic to E. heros, it exhibited lower toxicity for egg parasitoids, as there was no effect on parasitism and the emergence of wasps. We discuss likely explanations for such selectivity. In summary, we found that the essential oil was promising for the control of E. heros, because it caused deleterious effects at all development stages of the stink bug and had no effect on parasitism and emergence of the egg parasitoids, which suggested compatibility with biological control.

Schinus molle: anatomy of leaves and stems, chemical composition and insecticidal activities of volatile oil against bed bug (Cimex lectularius)

Abstract The present work investigates the leaf and stem anatomy, chemical composition and insecticidal activities (against Cimex lectularius Linnaeus, 1758) of the volatile oils of Schinus molle L., Anacardiaceae, a Brazilian native traditional medicinal plant. Noteworthy micro-morphological features that can help in the identification and quality control of the species include the presence of isobilateral and amphistomatic leaves, anomocytic and cyclocytic stomata, capitate glandular and conical non-glandular trichomes, large secretory ducts in the midrib, presence of druses and prismatic crystals, and the petiole vascular system comprising of five vascular bundles arranged in U-shape and an additional dorsal bundle. The major components of the volatile oil include β-pinene (14.7%), α-pinene (14.1%), limonene (9.4%) and muurolol (11.8%). Insecticidal activities of the volatile oil against bed bugs were investigated for the first time; strong toxicity by fumigation with the volatile oil of S. molle was observed and reported herein.

Natural insecticide based-leaves extract of Piper aduncum (Piperaceae) in the control of stink bug brown soybean / Inseticida natural a base de extrato de folha de Piper aduncum (Piperaceae) no controle do percevejo marrom da soja

This research aimed to evaluate the insecticide potential of the leaves extract of Piper aduncum (L.) (Piperaceae) on development of brown stink bug, Euschistus heros (F.), major pest in soybean crop in Mato Grosso State. For this a bioassay was conducted with eggs, nymphs and adults of this stink bug, using the concentrations 0.5; 1.0; 2.0; 4.0 and 8.0%, of the extract acetonic of P. aduncum and acetone for control. It was evaluated the numbers of unviable eggs, nymphs death and longevity, fecundity and fertility of the adults. In the immersing eggs bioassay, all concentrations greater than 1% unviable more than 70% of the eggs, while in the contact bioassay only 19% of the eggs were unviable in 8% concentration, differing of control. In nymphs bioassay the concentrations of 8% and 4% caused death of 72% and 52%, respectively. In adults bioassay all concentrations tested reduced significantly the survival and reproduction of the insects. Thus is evidence that P. aduncum is a potential plant for stink bug control, because it had deleterious action in all development phases on E. heros. .

Esta pesquisa avaliou o potencial inseticida do extrato de folhas de Piper aduncum (L.) (Piperaceae) sobre o desenvolvimento do percevejo marrom, Euschistus heros (F.), a principal praga da soja no Mato Grosso. Para este estudo, foram realizados bioensaios com ovos, ninfas e adultos do percevejo, utilizando as concentrações de 0,5; 1,0; 2,0; 4,0 e 8,0%, do extrato acetônico de P. aduncum e como controle acetona P.A. Foram avaliados o número de ovos inviáveis, a mortalidade de ninfas e a longevidade, fecundidade e fertilidade dos adultos. No bioensaio de imersão dos ovos, todas as concentrações maiores que 1% tornou inviável mais de 70% dos ovos, enquanto, no bioensaio de contato, apenas 19% dos ovos foram inviabilizados na concentração 8%, diferindo do controle. No bioensaio com ninfas, as concentrações de 8% e 4% ocasionaram morte de 72% e 52%, respectivamente. No bioensaio com adultos, todas as concentrações testadas reduziram significativamente a sobrevivência dos insetos e a reprodução dos insetos. Assim, ficou evidente que P. aduncum é uma planta com potencial para o controle do percevejo marrom, pois teve ação deletéria em todas as fases de desenvolvimento de E. heros. .