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 product. Quality control is thus a critical aspect in the use of the species as a medicinally active plant. Chromatographic techniques, such as TLC, GC, and HPLC, are useful for chemical profiling and verification of the presence of medicinally active constituents, but are quite limited in their ability to detect non-chemical contaminants, such as dirt, insects, and molds and other adulterants, such as wood, sand, and plant materials. The current study investigated and compared the use of botanical microscopy and chemical analysis for identifying adulterants in bilberry fruit. The experimental results demonstrated that chemical analysis was insufficient, while microscopy readily detected contaminating materials in bilberry fruit

Rapid staining method to detect and identify downy mildew (Peronospora belbahrii) in basil1

• 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

An improved clearing and mounting solution to replace chloral hydrate in microscopic applications1

• 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

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

Rapid Staining Method to Detect and Identify Downy Mildew (<i>Peronospora belbahrii</i>) 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

Intraespecific variation in leaf oils of Lippia junelliana (mold.) tronc

The purpose of this work was to assess the essential oil variation of Lippia junelliana from 16 different sites of mid-west Argentina. The essential oil of L. junelliana was dominated by monoterpenes (70-94%) with low amount of sesquiterpenes (3-10%) and phenylpropanoids (0.2-3%). More than 80 compounds were detected in the species. However, only eight were found as major component in the oils. According to these components, four wild chemotypes were detected. The first chemotype contained high levels of ocimenone (54-76%) with lower amounts of myrcene (10%). The second was composed of large amounts of dihydrocarvone (59-80%). The main constituents found in the third chemotype were limonene (10-40%) and piperitenone (10-40%) and the fourth chemotype contained limonene (41%) and piperitenone oxide (26%). © 2002 Elsevier Science Ltd. All rights reserved.Fil: Juliani Jr., Héctor R.. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; Argentina. Universidad Nacional de la Rioja; ArgentinaFil: Koroch, Adolfina R.. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Juliani, Hector Rodolfo. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Trippi, Victorio Segundo. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas, Físicas y Naturales; ArgentinaFil: Zygadlo, Julio Alberto. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Córdoba. Instituto Multidisciplinario de Biología Vegetal. Universidad Nacional de Córdoba. Facultad de Ciencias Exactas Físicas y Naturales. Instituto Multidisciplinario de Biología Vegetal; Argentin