of natural menthol because its essential oil contains high concentrations of menthol ( Galeotti et al., 2002 ; Lawrence, 2007 ; Zheljazkov et al., 2010a ). Japanese cornmint is grown in India, China, Japan, Paraguay, and Brazil ( Lawrence, 2007
Santosh Shiwakoti, Henry Y. Sintim, Shital Poudyal, Jennifer Bufalo, Charles L. Cantrell, Tess Astatkie, Ekaterina Jeliazkova, Lyn Ciampa and Valtcho D. Zheljazkov
Valtcho D. Zheljazkov and Tess Astatkie
., 2004 ; Clark, 1998 , Lawrence, 2007 ; Topalov and Zheljazkov, 1991 ; Zheljazkov et al., 1996a ). Japanese cornmint essential oil is rich in menthol and the species is currently the only commercial source for the production of natural menthol ( Clark
Valtcho D. Zheljazkov, Vasile Cerven, Charles L. Cantrell, Wayne M. Ebelhar and Thomas Horgan
chromatogram (TIC) of 20,000, a prescan ionization time of 100 μsec, an ion trap temperature of 150 °C, manifold temperature of 60 °C, and a transfer line temperature of 170 °C. Quantitative analysis. Commercial standards (-)-menthol, (-)-menthone
Berry fruits such as blackberries (Rubus sp.) and blueberries (Vaccinium corymbosum L.) are highly perishable after harvest. In addition to rapid deterioration in quality, they are also very susceptible to microbial invasion. The shelf life of these berries is usually terminated by decay. Several natural antimicrobial compounds derived from essential oils of plants were studied for their efficacies in inhibiting decay and extending shelf life of berry fruits. The severity of decay in blackberries and blueberries stored at 10 °C was significantly reduced by treatment with thymol. Treatments with menthol or eugenol also suppressed the fungal growth, but to a lesser extent. All of these three natural antimicrobial compounds extended shelf life of blackberries and blueberries as compared to the control. Berries treated with thymol, menthol, or eugenol also maintained better fruit quality with higher levels of sugars, organic acids, and oxygen radical absorbance capacity than the untreated fruits. The effects of these natural antimicrobial agents on the quality and shelf life of other fruits will be investigated.
K.J. Vining, Q. Zhang, A.O. Tucker, C. Smith and T.M. Davis
Mentha longifolia, a wild relative of the polyploid, cultivated Mentha (mint) species, was evaluated as a potential model system for genetic research relevant to the cultivated mints. Fourteen Mentha longifolia accessions maintained by the US Department of Agriculture (USDA), Agricultural Research Service, National Clonal Germplasm Repository (NCGR), were highly diverse with respect to geographic origin, oil composition, verticillium wilt resistance, aspects of morphology, and molecular marker polymorphism. Accession CMEN 584 was the only carvone chemotype, while CMEN 682 was the only accession with high menthol content. Trans-piperitone oxide was the primary oil component of accessions CMEN 17 and CMEN 18, while pulegone was most abundant in CMEN 20, CMEN 500, CMEN 501, and CMEN 585. Four accessions—CMEN 585, CMEN 17, CMEN 501, and CMEN 81—were consistently resistant to verticillium wilt, while CMEN 584 and CMEN 516 were highly susceptible. Pairwise similarity coefficients were calculated and a UPGMA (unweighted pair-group analysis) tree was constructed on the basis of 63 informative randomly amplified polymorphic DNA (RAPD) marker bands. CMEN 585 and CMEN 584 shared the greatest number of bands (16), and formed a distinct cluster in the UPGMA tree. Seven pairs of accessions had no bands in common, emphasizing the high degree of molecular diversity represented by these accessions. The favorable features of diploid (2n = 2x = 24) genome constitution, comparatively small genome size (400 to 500 Mb), self-fertility, fecundity, and diversity with respect to economically relevant traits, contribute to M. longifolia's potential usefulness as a model system for the cultivated mints. As a perennial species amenable to vegetative propagation, M. longifolia's spectrum of susceptibility/resistance to an important vascular wilt disease encourages its further evaluation as a system for broader studies of plant–microbe interactions and disease resistance mechanisms.
Valtcho D. Zheljazkov, Tess Astatkie, Thomas Horgan and S. Marie Rogers
-limonene, 1.8 cineole, paracimene, transsabinenehydrate, l-menthone, menthofuran, d-isomenthone, b-bourbonene, menthyl acetate, neo-menthol, b-cariophyllene, l-menthol, pulegone, germacrene-d, and piperitone. The major constituent was L-menthol, which varied
Valtcho D. Zheljazkov, Tess Astatkie, Santosh Shiwakoti, Shital Poudyal, Thomas Horgan, Natasha Kovatcheva and Anna Dobreva
-pinene, camphene, sabinene, β-pinene, 1-octen-3-ol, myrcene, hexenyl acetate, paracymene, limonene, eucalyptol, cis-sabinene hydrate, paracymenenene, cis-thujone, transthujone, isothujol, camphor, borneol, menthol, 4-terpineol, paramethyl acetophenone/paracymen-8
Paul D. Curtis and Jason R. Boulanger
menthol in the experimental extracts evaporate as well as to prevent freezing of repellents in the field. Japanese yews, with root systems balled and covered in burlap, were transported into fields and backyards of cooperating landowners during the week of
Procrustes analysis (GPA). T. hyemalis and T. vulgaris had 36 and 28 aroma-active compounds, respectively, perceived in a consensus by the two GC-O panelists. For T. hyemalis , the VEG stage was characterized by high green/menthol peak intensity due to