Valerian Ciobota

Dr. Valerian Ciobota


Research Focus & Metrics

Academic Career Length

18Years (2009-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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27 May 2015 in Cosmetics
Verified
Journal Article
Open access
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PJPaul Vargas Jentzsch
Paul Vargas Jentzsch
LRLuis Ramos
Luis Ramos
VCValerian Ciobota
Valerian Ciobota
Essential oils are highly appreciated by the cosmetics industry because they have antimicrobial and antioxidant properties, among others. Since essential oils are natural products, their inclusion in cosmetic formulations is a common practice. Currently, low-quality and/or adulterated essential oils can be found on the market; therefore, analytical methods for control are required. Raman spectroscopy is a versatile technique that can be used for quality control tasks; the portability of modern devices expand the analytical possibilities also to in situ measurements. Fifteen essential oils of interest for the cosmetics industry were measured using a handheld Raman spectrometer, and the assignment of the main bands observed in their average spectra was proposed. In most cases, it is possible to distinguish the essential oils by a simple visual inspection of their characteristic Raman bands. However, for essential oils extracted from closely-related vegetable species and containing the same main component in a very high proportion, the visual inspection of the spectra may be not enough, and the application of chemometric methods is suggested. Characteristic Raman bands for each essential oil can be used to both identify the essential oils and detect adulterations.

24 March 2016 in Analytical Methods
Verified
Journal Article
Closed access
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SYSivaprasad Yeturu
Sivaprasad Yeturu
PJPaul Vargas Jentzsch
Paul Vargas Jentzsch
VCValerian Ciobota
Valerian Ciobota
RGRicardo Guerrero
Ricardo Guerrero
PGPatricia Garrido
Patricia Garrido
LRLuis Ramos
Luis Ramos
Plant diseases have a direct impact on the productivity of crops, and therefore the early detection of diseases is crucial. Abutilon mosaic virus (AbMV) (family Geminiviridae; genus Begomovirus) is an important virus infecting ornamental crops throughout the world. Abutilon hybridum showing bright yellow mosaic symptoms were observed in gardens in Tumbaco, Ecuador. The infection was confirmed by Polymerase Chain Reaction (PCR) using degenerate begomovirus primers. The amplicon (∼500 bp) was sequenced, submitted to NCBI (KP877621) and showed 68.7–100% and 72.7–100% sequence identity with other begomoviruses at nucleotide and amino acid levels, respectively. In order to evaluate Raman spectroscopy as a diagnostic tool for AbMV infection, spectra of leaves from healthy and infected plants were recorded. Raman signals of carotenoids are the most important features and there is a significant decrease in the intensity of these bands when the plant is infected. The difference in the intensity of the bands, particularly the one at 1526 cm−1, is proposed as a basis for the early detection of viral infection in plants.

13 May 2014 in Flavour and Fragrance Journal
Verified
Journal Article
Closed access
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PJPaul Vargas Jentzsch
Paul Vargas Jentzsch
VCValerian Ciobota
Valerian Ciobota

15 December 2017 in Flavour and Fragrance Journal
Verified
Journal Article
Closed access
PDF file
PJPaul Vargas Jentzsch
Paul Vargas Jentzsch
FGFernando Gualpa
Fernando Gualpa
LRLuis Ramos
Luis Ramos
VCValerian Ciobota
Valerian Ciobota

20 March 2019 in Foods
Verified
Journal Article
Open access
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LSLorena Salvador
Lorena Salvador
Michelle GuijarroMichelle Guijarro
Michelle Guijarro
DRDaniela Rubio
Daniela Rubio
BABolívar Aucatoma
Bolívar Aucatoma
TGTanya Guillén
Tanya Guillén
LRLuis Ramos
Luis Ramos
Honey is one of the oldest sweetening foods and has economic importance, making this product attractive to adulteration with cheap sugars. This can cause a critical problem in the honey industry and a possible health risk. The present work has the aim of evaluating the authenticity of honey commercialized in two different provinces of Ecuador (Pichincha and Loja) by performing physicochemical and spectroscopic analyses. For this study 25 samples were collected from different places and markets and characterized by water, sucrose, reducing sugars and electric conductivity measurement. Also, their Raman and Infrared (IR) spectra were recorded and analysed using a Principal Component Analysis (PCA) in order to verify the quality of the honeys. In addition, a screening of several pesticides was performed in order to verify possible chemical threats to human health and honey bees. It was found that 8 samples have a deviation from the Standard established parameters. Two of them have a high difference in the content of sucrose and reducing sugars, which are located deviated from all the other samples in the PCA of the applied vibrational spectroscopy (IR/Raman), shaping two clear clusters. The results show that Raman and IR spectroscopy is appropriate techniques for the quality control of honey and correlates well with the physicochemical analyses.

1 November 2020 in Molecules
Verified
Journal Article
Open access
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FEFreddy R. Escobar-Ledesma
Freddy R. Escobar-Ledesma
VMVanessa Estefanía Sánchez Moreno
Vanessa Estefanía Sánchez Moreno
EVEdwin Vera
Edwin Vera
VCValerian Ciobota
Valerian Ciobota
PJPaul Vargas Jentzsch
Paul Vargas Jentzsch
LJLorena Jaramillo
Lorena Jaramillo
Inulin is a polysaccharide of fructose widely used in the food and pharmaceutical industry due to its physicochemical properties and technological applications. Inulin from jicama (Smallanthus sonchifolius) and cabuya (Agave americana) was obtained. The steps for inulin obtention were: raw material preparation, extraction and purification. The extraction conditions were determined using a random design with three levels of stirring speed (0, 130 and 300 rpm), and a 32 factorial experimental design with three levels of temperature (40, 60 and 80 °C) and solid:liquid ratio (1:2, 1:3 and 1:5 S:L). The results showed that the best extractions conditions for jicama were 130 rpm, 75 °C, 1:5 S:L and 25 min; while for cabuya were 80 °C, 300 rpm, 1:5 S-L and 100 min. The weight average molecular weight of inulin from jicama and cabuya were 5799.9 and 4659.75 g/mol, respectively. The identity of the obtained inulin from jicama and cabuya were confirmed by infrared (IR) and Raman spectroscopy. In addition, scanning electron microscopy, differential scanning calorimetry and thermogravimetry analyses were performed to characterize both inulins.