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Recebido em 08/12/2015; aceito em 12/01/2016; publicado na web em 12/04/2016 This paper summarizes a problematic nomenclature of isomers belonging to chlorogenic acid family since its first occurrence until present. During decades, there have been a high number of articles dealing with the family. Unfortunately, researchers who want to get knowledge about this topic may be strongly confused after reading a few articles. Due to gradual discoveries and isolations of the individual isomers from plenty of matrices and because of the changing system of terminology after these discoveries, discrepancies among articles are common. The cause of this confusion is that the main compound of the family, 5-caffeoylquinic acid (also wellknown as chlorogenic acid), was truly called as 3-caffeoylquinic acid before 1976, when new rules for nomenclature were published. Many researchers and also chemicals suppliers, however, keep using the "pre-IUPAC" nomenclature and wrongly call 3-caffeoylquinic acid as chlorogenic acid, the main substituent of the family. Despite there have been some works struggling with this issue, the problem is still appearing. Therefore, the present work was written.

Volatile compounds emitted by elderflowers (Sambucus nigra L.) at various stages (blooming on the bush, and at different stages after harvesting) were analyzed to investigate changes in the composition of volatile profiles induced by two drying procedures. Solid-phase microextraction and simultaneous distillation-solvent extraction were used for concentration of volatiles. Analyses of extracts were performed using gas chromatography coupled with a mass spectrometer or a flame ionization detector. On-site field sampling of volatiles followed-up by chromatographic analysis provided interesting information, including insect pheromones from 55 % to 79 % of the total peak area in the GC/MS chromatograms. Composition of aroma compounds of harvested elderflowers was strongly influenced by the type of drying procedure, where the content of some volatiles decreased and some substances even occur due to ongoing physicochemical processes. Changes in volatile profile caused by harvesting were also observed.

Essential oils obtained via the hydrodistillation of two Asian herbs (Houttuynia cordata and Persicaria odorata) were analyzed by gas chromatography coupled to mass spectrometry (GC–MS) and gas chromatography with flame ionization detector (GC–FID). Additionally, both the liquid and vapor phase of essential oil were tested on antimicrobial activity using the broth microdilution volatilization method. Antimicrobial activity was tested on Gram-negative and Gram-positive bacteria—Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterococcus faecalis, Streptococcus pyogenes, Klebsiella pneumoniae, Seratia marcescense and Bacillus subtilis. Hydrodistillation produced a yield of 0.34% (Houttuynia cordata) and 0.40% (Persicaria odorata). 41 compounds were identified in both essential oils. Essential oils contained monoterpenes and their oxidized forms, sesquiterpenes and their oxidized forms, oxidized diterpenes, derivates of phenylpropene and other groups, such as, for example, aldehydes, alcohols or fatty acids. Both essential oils were antimicrobial active in both vapor and liquid phases at least in case of one bacterium. They expressed various antimicrobial activity in the range of 128–1024 μg∙mL−1, 512–1024 μg∙mL−1 in broth and 1024 μg∙mL−1, 512–1024 μg∙mL−1 in agar, respectively. Research showed new interesting information about P. odorata and H. cordata essential oils and demonstrated that both essential oils could be possibly used in the field of natural medicine or natural food preservation.

Extensive traditional use of medical plants leads to research dealing with chemical composition of essential oils. The aim of this work was evaluation of quality of the essential oil and extending of the knowledge about chemical composition of essential oil from ribwort (Plantago lanceolata L.) and proportional representation of compounds. Extractions of essential oils from samples of ribwort were performed by hydrodistillation. GC-MS and GC-FID techniques were used for investigation of the qualitative and semi-quantitative content of aromatic compounds in the essential oils, respectively. Major aroma constituents of ribwort leaves were groups of fatty acids 28.0-52.1 % (the most abundant palmitic acid 15.3-32.0 %), oxidated monoterpenes 4.3-13.2 % (linalool 2.7-3.5 %), aldehydes and ketones 6.9-10.0 % (pentyl vinyl ketone 2.0-3.4 %) and alcohols 3.8-9.2 % (1-octen-3-ol 2.4-8.2 %). In relative high amount were identified apocarotenoids (1.5-2.3 %) which are important constituents because of their intense fragrant. The importance is in potential manufacture control of feedstocks before producing of food supplements.

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The following extraction techniques have been used for extracting antioxidants (apigenin, coumarin, esculetin, umbelliferone, bergapten, quercetin, rutin, scopoletin and xanthotoxin) from plant material: supercritical fluid extraction, pressurized liquid extraction, extraction by means of Soxhlet apparatus, ultrasonic extraction in ultrasonic bath, and by means of ultrasonic probe. The analytical method based on HPLC-UV detection for the determination of selected antioxidants was developed. For all extracts the antioxidant capacity based on the reduction of free 2,2-diphenyl-1-picrylhydrazyl radical was also determined. Comparing all results the ultrasonic probe method using 0.75 g of sample extracted by 50 mL of acetonitrile in water (30%, v/v) for 25 min at room temperature and with amplitude at 60% (equal to 90 W) without pulsation was evaluated as the best tool. The most significant indicator demonstrating this statement is the antioxidant capacity expressed as gallic acid equivalent where the ultrasonic probe method showed the best results in 10 of 16 samples. Also the operability of ultrasonic probe extraction method compared to other tested methods is more favorable.