Screening of Five Lamiaceae Essential Oils as Repellents for Sweet Potato Weevil, Cylas Formicarius (F.) (Coleoptera: Brentidae)

In this research, the repellent activity of five Lamiaceae essential oils, Agastache rugosa, Elsholtzia blanda, Elsholtzia ciliata, Elsholtzia penduliflora, and Plectranthus ovatus, was evaluated against sweet potato weevil, Cylas formicarius using a two-choice test between the essential oil-treated filter paper and the control. E. blanda and A. rugosa essential oils have some sweet potato weevil attractant properties at low dose (<47.16 nl/cm2),while N,N-diethyl-3-methylbenzamide (DEET), P. ovatus, E. penduliflora, and E.ciliata essential oils have repellent properties at doses ranging from 15.72 nl/cm2 to 196.49 nl/cm2. The effect of type of essential oil and their dose were interactively associated with repellent efficacy. There was a increase in repellent efficacy as the dose increased for all essential oils. The repellent activities of P. ovatus essential oil and E. penduliflora were higher than the others, and the repellent effects of E. ciliata essential oil and DEET were more dose-dependent than others, indicating that at low dose, P. ovatus and E. penduliflora essential oils have stronger repellent efficacy, but at higher dose DEET and E. ciliata have greater effects. Our findings clearly demonstrate that P. ovatus, E. penduliflora, and E. ciliata essential oils are candidate materials for future investigation as repellent compounds against sweet potato weevil control.

Pharmacognostic Study on Elsholtzia ciliata (Thumb.) Hyl: Anatomy, Phytochemistry and Pharmacological Activities

Elsholtzia ciliata (Thunb.) Hyl, family Lamiaceae, is an important and popular anti-bacterial and anti-inflammatory Traditional Chinese Medicine (TCM). However, there are limited scientific studies on its anatomy and pharmacological activities. Moreover, the information of chemical constituents in relation to its non-volatile constituents are still missing. The current study aimed to evaluate the anatomic, pharmacological and phytochemical profile of Elsholtzia ciliata, providing means for the quality control of this herbal drug. The methodology designed for this study included the preparation of anatomic sections and their description, extraction, chromatography, structural elucidation of isolated compounds by NMR techniques and their quantification by HPLC using pharmacological assays (Formalin, hot plate, DPPH, antimicrobial-Gram positive, Gram Negative and fungus, and MTT assays) to confirm the activities described for this species. Results of the anatomic study are aligned with the pattern expected for plants belonging to the Lamiaceae family; Ursolic acid and Oroxylin were isolated from this plant species. The findings observed in this study indicate that Elsholtzia ciliata possess anti-inflammatory, antinociceptive, antioxidant, antimicrobial and anticancer activities. The chemical compounds isolated from its leaves and the anatomy profile of its parts provide the basis for further quality control for this plant.

Дослідження технологічних параметрів сировини трави Ельшольції Стаунтона та трави Ельшольції війчастої для одержання екстрактів

Мета дослідження – визначення технологічних параметрів подрібненої рослинної сировини трави Ельшольції Стаунтона та трави Ельшольції війчастої (Патрена).Наведено результати дослідження технологічних параметрів подрібненої рослинної сировини: трави Ельшольціі Стаунтона (Elsholtzia Stauntonii Benth.) і трави Ельшольції війчастої (Патрена) (Elsholtzia ciliata, Elsholtzia Patrena Thunb.), що необхідні для розробки оптимальної технології отримання екстрактів у лабораторних і промислових умовах: вологiсть, питома, об’ємна та насипна густина сировини, пористiсть, порiзнiсть, вiльний об’єм шару, втрата в масі за висушування, зола загальна та зола нерозчинна в хлористоводневій кислоті, коефіцієнт поглинання. Також було визначено закономірність виходу екстрактивних речовин з обох видів сировини залежно від використаного екстрагента (вода, водно-спиртові суміші).Використовувались інструментальні та гравіметричні методи.У результаті проведених аналізів визначено наступні основні технологічні параметри трави Ельшольціі Стаунтона: питома густина – (1,26 ± 0,08) г/см3, об’ємна густина – (0,46 ± 0,03) г/см3, насипна густина – (0,078 ± 0,005) г/см3, пористість – (0,60 ± 0,04), порізність – (0,76 ± 0,04), вільний об’ємшару – (0,90 ± 0,05), зола загальна – (10,21 ± 0,61)%, зола нерозчинна в хлористоводневій кислоті – (0,58 ± 0,03) %, втрата в масі за висушування – (7,82 ± 0,23) %. Технологічні параметри трави Ельшольції війчастої: питома густина – (0,82 ± 0,05) г/см3, об’ємна густина – (0,30 ± 0,02) г/см3, насипна густина – (0,051 ± 0,003) г/см3, пористість – (0,39 ± 0,02), порізність – (0,52 ± 0,03), вільний об’єм шару – (0,75 ± 0,04), зола загальна – (8,75 ± 0,52) %, зола нерозчинна в хлористоводневій кислоті – (1,20 ± 0,07) %, втрата в масі за висушування – (6,59 ± 0,19) %.Домінуючий вихід екстрактивних речовин з трави Ельшольції Стаунтона спостерігався в разі використання 20 % етанолу як екстрагента, а з трави Ельшольції війчастої – води. Найкраща екстракція речовин з обох видів сировини досягається за співвідношення сировина:екстрагент 1:50.

Screening of the Repellent Activity of 12 Essential Oils Against Adult German Cockroach (Dictyoptera: Blattellidae): Preparation of a Sustained Release Repellent Agent of Binary Oil-γ-CD and its Repellency in a Small Container

Cockroaches are important sanitary pests and very difficult to control worldwide. With public concern about traditional insecticides, cockroach control agents should be environmentally friendly, highly efficient, and economical. In this article, 12 essential oils were screened to test their repellent effect against Blattella germanica. To develop essential oils as repellent agents, the oils were further examined in binary synergistic combinations. Ilex chinensis Sims (Sapindales: Aquifoliaceae) oil, Lavandula spp (Tubiflorae: Labiatae) oil, and Elsholtzia ciliata (Thunb.) Hyland (Tubiflorae: Labiatae) oil showed excellent repellent activities with lower RD50 (repellency dose for 50% of treated adults) values of 218.634, 154.590, and 223.989 µg/cm2, respectively, compared to those of other oils and the positive control. The I. chinensis oil and E. ciliata oil (weight ratio of 1:1.41) combination also displayed a remarkable synergistic effect against B. germanica. Their cotoxicity coefficient was 214.4. The major chemical constituents in E. ciliata and I. chinensis oils were respectively 3,7-dimethyl-1, 6-octadien-3-ol and methyl salicylate. The binary oil mixtures were formulated as a sustained release agent with γ-CD. The optimal preparation should be an 8:1 ratio of γ-CD to oils, with a 1 h stirring time, 50°C stirring temperature, and 1:12 ratio of γ-CD to ddH2O. The results of this study suggest that sustained release of binary oil-γ-CD exhibited a prolonged repellent activity (10 h) against B. germanica. This sustained-release agent could be further investigated and developed as a novel repellent preparation.

Antiarrhythmic Properties of Elsholtzia ciliata Essential Oil on Electrical Activity of the Isolated Rabbit Heart and Preferential Inhibition of Sodium Conductance

Elsholtzia ciliata essential oil (E. ciliata) has been developed in Lithuania and internationally patented as exerting antiarrhythmic properties. Here we demonstrate the pharmacological effects of this herbal preparation on cardiac electrical activity. We used cardiac surface ECG and a combination of microelectrode and optical mapping techniques to track the action potentials (APs) in the Langendorff-perfused rabbit heart model during atrial/endo-/epi-cardial pacing. Activation time, conduction velocity and AP duration (APD) maps were constructed. E. ciliata increased the QRS duration and shortened QT interval of ECG at concentrations of 0.01–0.1 μL/mL, whereas 0.3 μL/mL (0.03%) concentration resulted in marked strengthening of changes. In addition, the E. ciliata in a concentration dependent manner reduced the AP upstroke dV/dtmax and AP amplitude as well as APD. A marked attenuation of the AP dV/dtmax and a slowing spread of electrical signals suggest the impaired functioning of Na+-channels, and the effect was use-dependent. Importantly, all these changes were at least partially reversible. Our results indicate that E. ciliata modulates cardiac electrical activity preferentially inhibiting Na+ conductance, which may contribute to its effects as a natural antiarrhythmic medicine.

Freeze-Drying Technique for Microencapsulation of Elsholtzia ciliata Ethanolic Extract Using Different Coating Materials

The present study reports on the encapsulation of Elsholtzia ciliata ethanolic extract by freeze-drying method using skim milk, sodium caseinate, gum Arabic, maltodextrin, beta-maltodextrin, and resistant-maltodextrin alone or in mixtures of two or four encapsulants. The encapsulation ability of the final mixtures was evaluated based on their microencapsulating efficiency (EE) of total phenolic compounds (TPC) and the physicochemical properties of freeze-dried powders. Results showed that the freeze-dried powders produced using two encapsulants have a lower moisture content, but higher solubility, Carr index, and Hausner ratio than freeze-dried powders produced using only one encapsulant in the formulation. The microencapsulating efficiency of TPC also varied depending on encapsulants used. The lowest EE% of TPC was determined with maltodextrin (21.17%), and the highest with sodium caseinate (83.02%). Scanning electron microscopy revealed that freeze-drying resulted in the formation of different size, irregular shape glassy particles. This study demonstrated good mucoadhesive properties of freeze-dried powders, which could be incorporated in buccal or oral delivery dosage forms. In conclusion, the microencapsulation of E. ciliata ethanolic extract by freeze-drying is an effective method to produce new value-added pharmaceutical or food formulations with polyphenols.

Toxicity and Synergistic Effect of Elsholtzia ciliata Essential Oil and Its Main Components against the Adult and Larval Stages of Tribolium castaneum

Investigations have indicated that storage pests pose a great threat to global food security by damaging food crops and other food products derived from plants. Essential oils are proven to have significant effects on a large number of stored grain insects. This study evaluated the contact toxicity and fumigant activity of the essential oil extract from the aerial parts of Elsholtzia ciliata and its two major biochemical components against adults and larvae of the food storage pest beetle Tribolium castaneum. Gas chromatography–mass spectrometry analysis revealed 16 different components derived from the essential oil of E. ciliata, which included carvone (31.63%), limonene (22.05%), and α-caryophyllene (15.47%). Contact toxicity assay showed that the essential oil extract exhibited a microgram-level of killing activity against T. castaneum adults (lethal dose 50 (LD50) = 7.79 μg/adult) and larvae (LD50 = 24.87 μg/larva). Fumigant toxicity assay showed LD50 of 11.61 mg/L air for adults and 8.73 mg/L air for larvae. Carvone and limonene also exhibited various levels of bioactivity. A binary mixture (2:6) of carvone and limonene displayed obvious contact toxicity against T. castaneum adults (LD50 = 10.84 μg/adult) and larvae (LD50 = 30.62 μg/larva). Furthermore, carvone and limonene exhibited synergistic fumigant activity against T. castaneum larvae at a 1:7 ratio. Altogether, our results suggest that E. ciliata essential oil and its two monomers have a potential application value to eliminate T. castaneum.