Essential Oils from Bolivia. XV. Herzogole, an Original Monoterpene Benzodioxole from an Essential Oil from Pentacalia herzogii (Cabrera) Cuatrec.

Over 15 years, with the support of a Canadian funding agency, the Universidad Mayor de San Simón, in Bolivia, undertook a large survey of aromatic plants of the South American country. More than a hundred species were studied under various aspects, including the production and characterization of essential oils. As part of this survey, the chemical composition of an essential oil sample obtained from Pentacalia herzogii (Asteraceae) growing wild in the High Valley region of the department of Cochabamba was determined by a combination of GC and GC-MS measurements. α-Pinene was the main constituent of this essential oil (34%), accompanied by limonene (22%) and germacrene D (7.5%) as well as an important fraction of methoxylated monoterpenoids. They were mainly isomers of thymol methyl ether, accounting for 13% of the chromatogram. A new quantitatively important compound (9%) was identified through NMR and chemical synthesis as 4-isopropyl-6-methylbenzo[d][1,3]dioxole, and designated herzogole, alongside the minor related compound 1-isopropyl-2,3-dimethoxy-5-methylbenzene. The monoterpene benzodioxole featured a distinctive green-phenolic aroma which could raise interest for fragrance use. Since these compounds were not known naturally, a biosynthetic mechanism of their formation was proposed and put in perspective to illustrate the metabolic originality of P. herzogii.

Variability of the Chemical Composition and Bioactivity between the Essential Oils Isolated from Male and Female Specimens of Hedyosmum racemosum (Ruiz & Pav.) G. Don.

Hedyosmum racemosum (Ruiz & Pav.) G. is a native species of Ecuador used in traditional medicine for treatment of rheumatism, bronchitis, cold, cough, asthma, bone pain, and stomach pain. In this study, fresh H. racemosum leaves of male and female specimens were collected and subjected to hydrodistillation for the extraction of the essential oil. The chemical composition of male and female essential oil was determined by gas chromatography-gas chromatography equipped with a flame ionization detector and coupled to a mass spectrometer using a non-polar and a polar chromatographic column. The antibacterial activity was assayed against five Gram-positive and two Gram-negative bacteria, and two dermatophytes fungi. The scavenging radical properties of the essential oil were evaluated by DPPH and ABTS assays. The chemical analysis allowed us to identify forty-three compounds that represent more than 98% of the total composition. In the non-polar and polar column, α-phellandrene was the principal constituent in male (28.24 and 25.90%) and female (26.47 and 23.90%) essential oil. Other main compounds were methyl chavicol, germacrene D, methyl eugenol, and α-pinene. Female essential oil presented a strong activity against Klebsiella pneumoniae (ATCC 9997) with an minimum inhibitory concentration (MIC) of 500 µg/mL and a scavenging capacity SC50 of 800 µg/mL.

Biological Evaluation of Essential Oils from Selected Medicinal Plants and Their Main Components against Phytomonas davidi (Kinetoplastea: Trypanosomatidae).

Eight essential oils (EOs) from selected medicinal plants have been tested for their activity against Phytomonas davidi, a plant trypanosomal parasite. In the present research, the EOs have been tested on promastigote forms of P. davidi ATCC® 30287™ strain, along with their major components, both separately and in binary combinations, using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) reduction assay. The EOs with the highest antipromastigote activity were from Origanum virens and Salvia lavandulifolia. Thymol and ß-pinene were the most active pure compounds. The study of the activity of the pure compounds in combination indicated the existence of antagonistic and synergistic effects depending on the concentration tested. In general, the combinations at low concentrations favored the activity.

Encapsulation of Bunium persicum essential oil using chitosan nanopolymer: Preparation, characterization, antifungal assessment, and thermal stability.

The present study reports the antifungal, aflatoxin B1 inhibitory, and free radical scavenging activity of chitosan-based nanoencapsulatedBunium persicum Boiss. essential oil (Ne-BPEO). The chemical profile ofBPEO was identified through Gas chromatography mass spectrometry analysis where cuminaldehyde (21.23%), sabinene (14.66%), and γ-terpinen (12.49%) were identified as the major compounds. Ne-BPEO was prepared using chitosan and characterised by Scanning electron microscope (SEM), Atomic force microscope (AFM), Fourier-transform infrared spectroscopy (FTIR), and X-ray diffraction (XRD) assay. Ne-BPEO completely inhibited the growth and aflatoxin B1 production at a concentration of 0.3 µL/mL. The antifungal and aflatoxin B1 inhibitory effects were related to decreasing in ergosterol content, leakage of membrane ions (Ca2+, K+, and Mg2+), impairment in carbohydrate catabolism, and functioning of ver-1 gene of A. flavus exposed to Ne-BPEO over the control. In addition, Ne-BPEO exhibited promising free radical scavenging activity through DPPH assay (IC50 12.64 µL/mL) with high thermo-stability. Therefore, chitosan could be used as a carrier agent of plant-based preservative to enhance the shelf-life of food products against A. flavus and aflatoxin B1 contamination.

Ethnobotany and Pharmacology of Pinus Species Growing Naturally in Indian Himalayas: A Plant Review.

Pinus species are amongst the most commonly used medicinal plants in Indian Northwestern Himalayas. Nearly all parts of the plant especially needles are believed to possess medicinal and clinical values in traditional systems of medicine such as Ayurvedic, Unani or Homeopathic. They are used to heal numerous diseases, including afflictions of the skin, eyes, throats and ears. Various parts of the plant including needles are rich in biologically active compounds, such as thunbergol, 3-carene, cembrene, α-pinene, quercetin, xanthone, etc. The scientific data available for the biological potential of this plant and its constituents have been found to be scanty and also does not satisfy the basis of their age-old folklore and local uses. This review focuses on a detailed analysis of ethnopharmacognosical studies on the needles of different Pinus species growing naturally in northwestern region of Indian Himalayas including investigations and findings that have come up with a concrete view of the abilities of plant components for example phenolics, flavonoids, tannins and other constituents to treat oxidative, inflammatory and microbial responses. Careful evaluation of the data presented may be helpful for the researchers to discover and evaluate the specific chemical entities responsible for the traditional medicinal uses of P. roxburghii, P.wallichiana, P. merkusii, P.kesiya and P.thunbergii.