Adolfina R. Koroch

Bioactivity of Essential Oils and Their Components

The present review demonstrates that EOs and their components have many functional properties and exert their action in mammals as well as in other organisms (insects, fungi, bacteria and viruses). The synergistic effect of EO components is a promising field that could lead to the optimisation of a given bioactivity. This phenomenon has been observed in many activities, such as those of antimicrobials, antioxidants, analgesics and semiochemicals. EOs are complex mixtures of components that show higher activities than their isolated components; their final activities are due to the combine effects of several minor components. Thus, EOs contain multifunctional components that exert their activities through different mechanisms. EOs and their components may have new applications against various diseases of different origins (cancer, fungal, bacterial or viral), because some of these complex diseases require multiple components and multifunctional therapies.

In vitro regeneration of Echinacea pallida from leaf explants

SummaryA method has been developed for the induction of adventitious shoots from leaf tissue of Echinacea pallida with subsequent whole-plant regeneration. Proliferating callus and shoot cultures were derived from leaf tissue explants placed on Murashige and Skoog medium supplemented with 6-benzylaminopurine and naphthaleneacetic acid combinations. The optimum shoot regeneration frequency (63%) and number of shoots per explant (2.3 shoots per explant) was achieved using media supplemented with 26.6 μM 6-benzylaminopurine and 0.11 μM naphthaleneacetic acid. Rooting of regenerated shoot explants was successful on Murashige and Skoog medium, both with and without the addition of indole-3-butyric acid. All plantlets survived acclimatization, producing phenotypically normal plants in the greenhouse. This study demonstrates that leaf tissue of E. pallida is competent for adventitious shoot regeneration and establishes a useful method for the micropropagation of this important medicinal plant.

An Improved Clearing and Mounting Solution to Replace Chloral Hydrate in Microscopic Applications

Premise of the study: This study presents Visikol™, a new proprietary formulation that can be used as an efficient replacement for chloral hydrate as a clearing agent for microscopic examination. In the United States, chloral hydrate is regulated and therefore difficult to acquire. Methods and Results: Fresh and dry samples of the following plants: ginger (Zingiber officinale), maté (Ilex paraguariensis), lime basil (Ocimum americanum), oregano (Origanum vulgare), and mouse-ear cress (Arabidopsis thaliana), were cleared using Visikol or chloral hydrate solution and compared using a light microscope. Conclusions: This new method can be used successfully to clear specimens, allowing identification of diagnostic characteristics for the identification of plant materials. Visikol is as effective as chloral hydrate in providing clarity and resolution of all tissues examined. Tissues become transparent, allowing observation of deeper layers of cells and making it effective in research, botanical and quality control, and for educational applications.

Estimation of nuclear DNA content of cultivated Ocimum species by using flow cytometry

Ocimum spp. are cultivated worldwide for culinary and medicinal uses. Some species are the subjects of improvement in breeding programs while others are still collected from the wild. Polyploidy and dysploidy are common features of the cultivated species. Taxonomical confusion has arisen in the classification of Ocimum spp., in part due to the ease with which many of the species intercross and the morphological similarities between several of the species. Flow cytometry is a fast and easy method to measure nuclear DNA content and could be a useful tool to assess germplasm accessions in a breeding program. Here we report the first estimates of nuclear DNA content of eight Ocimum spp., as determined by flow cytometry. The 2C nuclear DNA content ranged from 928 (O. campechianum) to 5515 Mbp (O. americanum). The nuclear DNA content levels may be useful for better understanding of the taxonomical relationships among species.

Antioxidant activity, total phenolics, and rosmarinic acid content in different basils (Ocimum spp.).

Basil (Ocimum spp.) has been used for many years in foods as a flavoring agent, in perfumery, and in medicine. The antioxidant capacity as Trolox equivalent antioxidant capacity (TEAC) and total phenolic contents, based on Folin-Ciocalteu reagent, in different Ocimum species were quantitated. High-performance liquid chromatography (HPLC) was used to identify and quantify rosmarinic acid, the predominant nonvolatile polyphenol in each Ocimum species. Among seven Ocimum spp. there was a wide range of antioxidant activity. A high linear correlation between total antioxidant capacity and phenolic content was observed (r2 = 0.8822), and a positive relationship also existed between antioxidant activity and rosmarinic acid (r2= 0.8393). Antioxidant capacity was associated with the plants phenolic components and with rosmarinic acid. Our results demonstrated that those species rich in phenolic constituents demonstrated high antioxidant activity, and that rosmarinic acid is a major contributor to this activity in...

Rapid staining method to detect and identify downy mildew (Peronospora belbahrii) in basil.

Premise of the study: Demand for fresh-market sweet basil continues to increase, but in 2009 a new pathogen emerged, threatening commercial field/greenhouse production and leading to high crop losses. This study describes a simple and effective staining method for rapid microscopic detection of basil downy mildew (Peronospora belbahrii) from leaves of basil (Ocimum basilicum). Methods and Results: Fresh leaf sections infected with P. belbahrii were placed on a microscope slide, cleared with Visikol™, and stained with iodine solution followed by one drop of 70% sulfuric acid. Cell walls of the pathogen were stained with a distinct coloration, providing a high-contrast image between the pathogen and plant. Conclusions: This new staining method can be used successfully to identify downy mildew in basil, which then can significantly reduce its spread if identified early, coupled with mitigation strategies. This technique can facilitate the control of the disease, without expensive and specialized equipment.

A first linkage map and downy mildew resistance QTL discovery for sweet basil (Ocimum basilicum) facilitated by double digestion restriction site associated DNA sequencing (ddRADseq)

Limited understanding of sweet basil (Ocimum basilicum L.) genetics and genome structure has reduced efficiency of breeding strategies. This is evidenced by the rapid, worldwide dissemination of basil downy mildew (Peronospora belbahrii) in the absence of resistant cultivars. In an effort to improve available genetic resources, expressed sequence tag simple sequence repeat (EST-SSR) and single nucleotide polymorphism (SNP) markers were developed and used to genotype the MRI x SB22 F2 mapping population, which segregates for response to downy mildew. SNP markers were generated from genomic sequences derived from double digestion restriction site associated DNA sequencing (ddRADseq). Disomic segregation was observed in both SNP and EST-SSR markers providing evidence of an O. basilicum allotetraploid genome structure and allowing for subsequent analysis of the mapping population as a diploid intercross. A dense linkage map was constructed using 42 EST-SSR and 1,847 SNP markers spanning 3,030.9 cM. Multiple quantitative trait loci (QTL) model (MQM) analysis identified three QTL that explained 37–55% of phenotypic variance associated with downy mildew response across three environments. A single major QTL, dm11.1 explained 21–28% of phenotypic variance and demonstrated dominant gene action. Two minor QTL dm9.1 and dm14.1 explained 5–16% and 4–18% of phenotypic variance, respectively. Evidence is provided for an additive effect between the two minor QTL and the major QTL dm11.1 increasing downy mildew susceptibility. Results indicate that ddRADseq-facilitated SNP and SSR marker genotyping is an effective approach for mapping the sweet basil genome.

In Vitro Shoot Multiplication of Echinacea purpurea

ABSTRACT Cytokinin growth regulators, 6-benzylaminopurine (BAP), kinetin (KIN), and 2-isopentenyladenine (2-iP), induced in vitro shoot multiplication from shoot explants of Echinacea purpurea (Eastern purple coneflower). Murashige and Skoog (MS) medium supplemented with 17.76 μM 6-benzylaminopurine and 0.269 μM naphthalene acetic acid produced the greatest number of adventitious shoots, although all cytokinin treatments with or without naphthalene acetic acid were effective in inducing shoots. Subsequent rooting and growth of the induced shoots in a potting media in a greenhouse demonstrated the new plants developed normally.

Chemical Constituents of the Essential Oil of Hedeoma multiflorum Benth. (Lamiaceae)

The oil from the aerial parts of Hedeoma multiflorum Benth. (Lamiaceae) was analyzed by GC and GC/MS. It was found that the major components were menthone (14.1%), isomenthone (8.9%) and pulegone (62.1%).

Microscopy for Quality Assessment of Bilberry Fruit (Vaccinium myrtillus L.)

Bilberry is a traditional plant from which the berries have been eaten as a fresh fruit, made into jam, and included in some baked products for centuries. More recently, bilberries have become a popular dietary supplement and are among the best-selling fruit in the US market. Adulteration of bilberries in the marketplace, however, can occur due to misidentification or mixing with other species during harvesting and processing. Intentional adulteration also occurs through the purposeful addition of foreign materials to increase the apparent quality or reduce the cost of the final