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This research evaluated the chemical composition of Ocimum basilicum and Syzygium aromaticum and to characterize their complex with β-cyclodextrin (β-CD) using physical mixing, kneading, and co-precipitation methods. Gas chromatography coupled to a mass spectrometer showed that methyl-chavicol and eugenol were, respectively, the major compounds from O. basilicum and S. aromaticum. By the use different vibrational spectroscopic methods (ATR-FTIR and FT-Raman) and thermal analysis (DSC and TGA), it was possible to strongly suggest the formation of EO-β-CD complex. The antioxidant activity was evident in S. aromaticum EO due to the presence of the eugenol compound in the complexes. The antioxidant stability was evaluated at different temperatures, in which OE had its antioxidant activity reduced drastically while the complexes had a reduction of 6–13% of its activity. The antimicrobial activity was observed for EO and its complexes of S. aromaticum against yeasts of the genus Candida, in which there was a reduction of the concentration of the MIC and CFM for the complexes formed by the co-precipitation methodology. The antitumor activity against HT-29 and HeLa cells was observed in both EOs, in contrast, the cytotoxicity of EOs was also increased. The complex formed from OE S. aromaticum showed the best antitumor activity against HT-29 cells (IC 50 = 12.5 µg/mL) with a better selectivity index (IS = 12.32). It is concluded that the techniques used were suitable for the confirmation of the complexes with β-CD, and that the complexation contributed with the stability and action of the essential oils evaluated, allowing their use in the various industrial sectors, such as pharmaceutical and food industry.

This study was to evaluate the biological activity of the extract of Botryosphaeria fabicerciana isolated from leaves of Morus nigra. The volatile compounds from the crude extract were analysed by GC-MS which demonstrate that mellein and β-orcinaldehyde were are the major compounds. The best minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of the extract was observed against Gram-positive bacteria, with a MIC of 15.6 μg/mL towards B. cereus and MIC of 62.5 μg/mL towards S. aureus and B. subtilis. MBC values of 31.25 μg/mL, 62.5 μg/mL, and 250 μg/mL were observed towards B. cereus, B. subtilis, and S. aureus, respectively. The cytotoxicity analyses showed CC50 of 115 μg/mL. The crude extract showed antioxidant activity by the DPPH, ABTS, and FRAP assays. Therefore, the extract of the endophytic fungus presented biotechnological potential as an antibacterial and antioxidant agent.

The purpose of this study was to determine the chemical profile of Litsea cubeba essential oil, carry out an in vitro evaluation of its antioxidant potential and its cytotoxicity, as well as its an...

There is an increasing demand for fungi control in grains, especially toxigenic. Also, there is growing concern on the use of synthetic fungicides; thus alternatives are needed. The aim of this stu...

Compilation studies related to toxicological aspects and also biological monitoring and analysis methods for specific fungicides and, mainly, those that belong to the class of the dithiocarbamates (DTCs) have not been carried out at least in the last ten years. DTCs - dimethyldithiocarbamates, ethylenebisditiocarbamates, propylenebisditiocarbamates - are organosulfur compounds that form complexes due to the presence of different chemical elements, which bind strongly and inhibit enzymes that are essential to the functioning of the organism, causing a serious proven adverse effect on biological systems, such as alteration of thyroid hormones, teratogenesis and neurotoxicity. It is still evident, as shown by world data, that the growing consumption of fungicides has increasingly exposed the population in general and, in particular, workers who deal with these substances. There is a scarcity of studies in the literature discussing the toxicological and analytical aspects that are important for understanding the real effects of DTCs and monitoring human exposure to them. Therefore, the aim of this work was to expose, in a comprehensive way and through a narrative review, gaps in research related to the fungicides of the DTCs class, their metabolites, as well as the toxicological and analytical aspects involved. The review is divided into two parts: (1) Toxicological aspects, including toxicokinetics, toxicodynamics and toxidromes; and (2) Analytical Toxicology, which comprises biomarkers, sample preparation and identification/quantification methods.

This study aimed to investigate the antimicrobial activity of kefir fermented fruit by-products against strains of Alicyclobacillus spp., and determine their chemical characterization and antioxidant activity. According to the results, extracts fermented for a longer period (72 h) showed greater inhibition, and the extract of acerola by-product fermented for 72 h achieved the best results. For all strains, the Minimal Inhibitory Concentration (MIC) was 0.78%, except for A. acidocaldarius subsp. rittmannii, (1.56%). The same applies to the Minimal Bactericidal Concentration (MBC), in which 1.56% of the extract was capable of inactivating A. cycloheptanicus and A. acidocaldarius. In addition, damages to the structure of the microorganisms caused by the extracts were detected by Scanning Electron Microscopy. Metabolite identification through liquid chromatography (UHPLC-Qtof-MS) showed that the fermented extracts had a greater number of compounds compared to the non-fermented ones, such as glucuronic, succinic and glutaric acids. In conclusion, the extracts of fruit by-products showed to have bioactive properties, such as antibacterial potential and antioxidant activity against the Alicyclobacillus strains tested in this study, not to mention the value added by the use of a food by-product.

In the present study, the biological activity of an extract of the secondary metabolites (E-G6-32) produced by the Curvularia sp. G6-32 endophyte (isolated from the medicinal plant Sapindus saponaria L.) was investigated. The antioxidant potential was confirmed by the DPPH (22.5%) and ABTS (62.7%) assays, and the total phenolic compound content was 40 µg gallic acid equivalents/mg. The extract E-G6-32 displayed good inhibitory activity toward butyrylcholinesterase (BuChE; IC50 = 110 ± 0.05 µg mL−1). The extract E-G6-32 was subjected to spectroscopic and mass spectrometry analyses. Comparison with the literature data confirmed that (-)-asperpentyn (1) was a major component. Asperpentyn belongs to the epoxyquinone family, which has attractive structural complexity, diverse functional groups, and a broad range of biological activities, including specific enzyme inhibitory activity. Our results suggest that Curvularia sp. G6-32 is a promising source of bioactive secondary metabolites and contains (-)-asperpentyn, which has potential pharmaceutical interest.

This study aimed to evaluate the antimycotoxigenic effect of essential oils (EOs) obtained from four different aromatic plants on the production of deoxynivalenol (DON) and zearalenone (ZEA) by

The Alicyclobacillus spp., causing deterioration in citrus beverages, has been frequently related to the use of natural antimicrobial agents in its combat; in this sense, the study sought to evaluate the activity of the essential oil of oregano (Origanum vulgare) against different isolates of this bacterium, in addition to its antioxidant activities. The minimum inhibitory concentration obtained from oregano essential oil for A. Acidiphilus and A. cycloheptanicus was 125 μg/mL; and for A. herbarius and A. acidoterrestris was 62.5 μg/mL. While the minimum bactericidal concentration obtained was 1000 μg / mL for all isolates. The combined effect of nisin and O. vulgare against A. acidoterrestris resulted in indifference. The antioxidant activity obtained was 363 μmol trolox/mg by the DPPH method and 1142 μmol trolox/mg by the ABTS method. The chemical characterization of the essential oil of oregano by GC–MS was able to identify of 93.13% of the compounds was carried out, where the major compound was carvacrol acetate represented by 59.61%. Further scanning electron microscopy was able to demonstrate damage to cells treated with the inhibitory concentrations of O. vulgare.

This study was to evaluate the biological activity of the extract of

This study aimed to evaluate the antimycotoxigenic effect of essential oils (EOs) obtained from four different aromatic plants on the production of deoxynivalenol (DON) and zearalenone (ZEA) by Fusarium graminearum. The EOs from ginger (GEO), turmeric (TEO), thyme (ThEO) and rosemary (REO) were obtained by hydrodistillation and identified by gas chromatography/mass spectrometry (GC/MS). The major compounds found were mostly monoterpenes and sesquiterpenes. The minimum inhibitory concentration (MIC) and minimum fungicide concentration (MFC) were 11.25, 364, 366 and 11,580 µg mL-1 for ThEO, GEO, REO and TEO, respectively. The results evidenced that the assessed EOs inhibited DON and partially ZEA production by F. graminearum. ThEO and GEO were the EOs with most potent antimycotoxigenic action for DON and ZEA, respectively. These EOs have shown promising results in vitro regarding inhibition of mycotoxin production and might be used in the future as substitutes for synthetic fungicides.

There is an increasing demand for fungi control in grains, especially toxigenic. Also, there is growing concern on the use of synthetic fungicides; thus alternatives are needed. The aim of this study was to evaluate the antifungal and antimycotoxigenic action of essential oils (EOs) from

This study aimed to evaluate the risk concerning child population's health because of the occurrence of AFM

In the present study, the biological activity of an extract of the secondary metabolites (E-G6-32) produced by the

The occurrence of mycotoxins synthesized by spoilage fungi has been reported in various crops. Despite being a crop susceptible to attack by microorganisms, such as Alternaria alternata, there are no reports on the production of mycotoxins in Hylocereus undatus (Haw.). The objective of the present study was to identify mycotoxins produced by A. alternata previously isolated from Hylocereus undatus (Haw.) fruit in the postharvest phase, and A. alternata ATCC 46,582, in vitro and in vivo. The compounds were identified using liquid chromatography-mass spectrometry (LC–MS/MS). Alternariol (AOH), alternariol monomethyl ether (AME), tentoxin (TEN), altertoxins (ATX) I, II and III were detected in vitro for A. alternata, and ATX I and II were identified for the reference strain, A. alternata ATCC 46,582, which was used as a positive control. Mycotoxins characteristic of A. alternata were not detected in vivo in the fruit stored for 8 d, which is its estimated shelf life. The use of LC–MS/MS facilitated rapid and efficient mycotoxin identification, contributing significantly to the evaluation of food safety.

This study isolated and identified the fungus that causes postharvest disease in dragon fruit (Hylocereus undatus Haw.). The in vitro and in vivo antifungal activity of some essential oils were evaluated against the fungus. Morphophysiological and molecular identification confirmed the fungus was Alternaria alternata. The essential oils of Cinnamomum zeylanicum, Cymbopogon flexuosus, Eucalyptus globulus, Eugenia caryophyllus, and Rosmarinus officinalis were evaluated by the microdilution broth technique, disc diffusion, scanning electron microscopy, and fluorescence microscopy. Evaluation of the composition of the essential oils by gas chromatography/mass spectrometry revealed substantial amounts of eugenol as a major constituent of E. caryophyllus and C. zeylanicum (90.50% and 80.70%, respectively). The other essential oils of R. officinalis contained α-pinene (24.5%) and camphor (22.0%) as major components. E. globulus contained 1,8-cineole (78.9%). C. flexuosus contained neral (35.1%) and geranial (42.6%). C. zeylanicum and E. caryophyllus were the most active against the isolated fungi at minimum inhibitory concentrations of 250 and 500 μg/ml, respectively, causing morphological changes in the hyphae. The in vivo assay indicated that the fruits that were treated with E. caryophyllus at concentrations of 500 and 1000 μg/ml exhibited a 31% reduction of mycelial growth compared with the control. These results suggest that the essential oils of C. zeylanicum and E. caryophyllus are active against A. alternata both in vitro and in vivo, which may be promising for control of the microorganism.

The use of rosemary essential oil (RO) and its combination with nisin (RO+N) in preventing the multiplication of Alicyclobacillus acidoterrestris in orange juice was evaluated. The minimum inhibitory and bactericidal concentrations (MIC and MBC) for RO were both 125 μg ml-1 while RO+N displayed a synergistic effect. The use of RO and RO+N at concentrations of 1, 4 and 8× MIC in orange juice for 96 h was evaluated in terms of their sporicidal effectiveness. With regard to the action against A. acidoterrestris spores, RO at 8× MIC was sporostatic, whereas RO+N at 1× MIC was sporicidal. Morphological changes in the structure of the micro-organism after treatment were also observed by microscopy. Furthermore, flow cytometric analysis showed that most cells were damaged or killed after treatment. In general, the antioxidant activity after addition of RO+N decreased with time. The results demonstrate that using the combination of RO and nisin can prevent the A. acidoterrestris growth in orange juice.

The aim of this study was developing formulations of H. undatus Haw. jam with pulp and peel, as well as evaluating nutritional compounds and texture properties through sensorial, instrumental, physical, biochemical and microbiological analyses of the final product. The fruit were selected, sanitized, pulped and grinded, and the formulations with different concentrations of pulp and peel (0 – 100%) were developed and evaluated. Microbiological evaluation showed that the formulations are in accordance with the current legislation. The increase in peel concentration in the jam formulations resulted in better consumer acceptance and higher concentration of phenolic compounds, antioxidants and B complex vitamins, such as B1, B5 and B6. In addition, it gave the jams acceptable and pleasant sensorial characteristics and texture. Adding peel to the formulations enabled us to make total use of the fruit, with no waste, besides making the coproduct richer in compounds that are beneficial to consumers’ health. El objetivo de este estudio fue desarrollar formulaciones de gelatina a partir de H. undatus Haw. con pulpa y piel, además de evaluar compuestos nutricionales y propiedades texturales mediante análisis sensorial, instrumental, físico, bioquímico y microbiológico del producto final. Los frutos fueron seleccionados, higienizados, despulpados y molidos, y se desarrollaron y evaluaron formulaciones con diferentes concentraciones de pulpa y piel (0 - 100%). La evaluación microbiológica mostró que las formulaciones están de acuerdo con la legislación vigente. El aumento de la concentración del peeling en las formulaciones de gelatina resultó en una mejor aceptación por parte del consumidor y una mayor concentración de compuestos fenólicos, antioxidantes y vitaminas B, como B1, B5 y B6. Además, estas formulaciones mostraron características sensoriales aceptables y agradables. La incorporación de las cáscaras a las formulaciones permitió aprovechar al máximo la fruta, sin desperdicio, además de enriquecer el coproducto en compuestos beneficiosos para la salud del consumidor. O objetivo deste estudo foi desenvolver formulações de geleia a partir de H. undatus Haw. com polpa e casca, além de avaliar compostos nutricionais e propriedades de textura por meio de análises sensoriais, instrumentais, físicas, bioquímicas e microbiológicas do produto final. Os frutos foram selecionados, sanitizados, despolpados e moídos, e as formulações com diferentes concentrações de polpa e casca (0 - 100%) foram desenvolvidas e avaliadas. A avaliação microbiológica mostrou que as formulações estão de acordo com a legislação vigente. O aumento da concentração da casca nas formulações de geleias resultou em melhor aceitação pelo consumidor e maior concentração de compostos fenólicos, antioxidantes e vitaminas do complexo B, como B1, B5 e B6. Além disso, estas formulações apresentaram características sensoriais aceitáveis e agradáveis. Adicionar as cascas às formulações possibilitou o aproveitamento total da fruta, sem desperdício, além de enriquecer o coproduto em compostos benéficos à saúde do consumidor.

The Conyza sp. is an annual or short-lived perennial weed of the Asteraceae family. Fructans are linear fructose polymers used in the food industry as a prebiotic nutrient, fat, and sugar substitute and in the pharmaceutical industry as a drug delivery system. The objective of this study was to chemically characterize preliminarily fructans from Conyza sp. roots: fructooligosaccharides (FOS) and inulin-type and evaluated the prebiotic potential activity of these molecules in vitro. Chemical analyses (1H NMR, 13C NMR, GC-MS, FT-IR, and off-line ESI-HRMS) confirmed the presence of the fructans molecules in the aqueous crude extracts of Conyza sp. roots. The study of the prebiotic effect of Conyza sp. fructans in vitro showed an ability to stimulated lactobacilli strains with growth slightly similar (Conyza FOS) and smaller (Conyza inulin) than the commercial prebiotic inulin available (Orafti® GR). These data suggest that Conyza sp. a weed that causes problems agronomic can be used as a promising source to obtain fructans, compounds with potential in the food and technological industries.

This study aimed to evaluate the risk concerning child population's health because of the occurrence of AFM1 in UHT milk, powdered milk (PM) and infant formulae (IF). Determination of AFM1 was performed in 60 samples and evaluation of the mycotoxin exposure was carried out through the determination of the estimated daily intake (EDI), whereas risk characterization was evaluated with the calculation of the risk of Hepatocellular Carcinoma (HCC) and the Margin of Exposure (MOE). AFM1 ranged from 150 to 1020 ng/kg, and all the positive samples exceeded the limits stablished by European Community. The EDI for AFM1 ranged according to the age group of the population studied (0–5 years old) from 0.828 to 2.523, 0–2.113 and 0.029–0.833 ng/kg b. w./day in UHT, PM and IF, respectively. The number of HCC cases associated with AFM1 exposure (0.0015 a 0.0045) was higher than the limit of 0.001 case/100,000. MOE values for AFM1 were 728 to 239, considerably below the security margin of 10,000. These results point to a potential risk to the health of Brazilian child population exposed to AFM1 in dairy products.

Alicyclobacillus acidoterrestris is a bacteria capable of spoiling industrialized orange juice, making it a problem for the beverage industry. This study evaluated the effect of UV-C radiation in combination with nisin in the reduction of A. acidoterrestris spores using reconstituted orange juice. A. acidoterrestris spores were treated with nisin (7.81 and 15.62 μg/mL) in combination with different doses of UV-C (from 2.52 to 12.6 kJ/m2). The presence of vitamins in the juice after the treatments was investigated by UHPLC-HRMS using a ultra high performance liquid chromatography system. The combination of UV-C and nisin treatment showed counts below the detection limit of the method (

Biocatalysis represents an efficient and versatile tool for organic synthesis and green chemistry, since enzymes can perform many chemical transformations with advantages over their chemical counterparts. (4R)-(−)-carvone and its reduced derivatives are natural products with biological and industrial applications, specially (1R,2S,4R)-neodihydrocarveol, due to its pharmacological properties, as well as fragrances supplies. Dialkyl imidazolium-based ionic liquids (ILs) are known to be useful in biocatalytic processes due to their unique physico-chemical properties, low toxicity and ability to improve enzymatic activity. In the present study, we describe the bioreduction of (4R)-(−)-carvone using a filamentous fungus isolated from human skin, molecularly identified by MLSA as Epicoccum sorghinum, and ionic liquid (IL) 1-butyl-3-methyl-imidazolium tetrafluoroborate ([BMIM][BF4]), as co-solvent. The addition of 0.2% (v/v) of [BMIM][BF4] favoured the bioreduction of the substrate (4R)-(−)-carvone at a concentration of 0.198 mmol, affording 65% of the major compound (1R,2S,4R)-neodihydrocarveol, with diastereomeric excess greater than 99% after 18 h of biocatalytic reaction. Also, the isolated product was obtained with an appreciable yield of 59% after column chromatography.

Natural antimicrobial is an effective alternative for control Alicyclobacillus spp., known to cause spoilage in fruit juices. Because of this, in this study, evaluated the antibacterial activity of green tea fermented at 7 and 14 days with Kombucha (K07 and K14). The species used were Alicycobacillus acidoterrestris 0244T, Alicyclobacillus herbarius 0246T, Alicyclobacillus acidiphilus 0247T, Alicyclobacillus cycloheptanicus 0297T, Alicyclobacillus hesperidum 0298T. Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) was performed against Alicyclobacillus. At 50% concentration of green tea, 1,563% K07 and 0.195% K14, there was a bacteriostatic effect (MIC) for all strains studied. While the minimum bactericidal concentration ranged from

Due to the currently abundant supply of marine microalgae, which can be found in seawater, as well as microalgae's ability to uptake different chemicals, it appears as a promising raw material with potential for many commercial uses. Despite having a high amount of metal in their biomass, the lipids within marine microalgae can be converted into biodiesel. Analyses of 26 chemical elements (Al, B, Ba, Be, Bi, Ca, Cd, Co, Cr, Cu, Fe, K, Li, Mg, Mn, Mo, Na, Ni, P, Pb, Sn, Sr, Ti, Tl, V, and Zn) were performed by ICP-OES with the goal of quantifying the inorganic content of marine microalgae's biomass. Regardless of the cultivation media used, microalgae presented differences in their chemical element profile. Strains showed a 12.9% to 36.3% mass of analyzed elements per dry biomass, which represent a relatively high percentage for a feedstock used in biofuels. Among the 36 assayed microalgae, Biddulphia sp., Planktolyngbya limnetica, Amphora sp. (1), Navicula sp. (3) and Synechococcus sp. are most indicated for this purpose as they contain a lower concentration of chemical elements when compared to other samples. However, their profile warns that water quality control is needed for toxic metals such as Ba, Cd, and Pb.

Os frutos de pitaia apresentam grande importância nutricional e economicamente vem se estabelecendo em diversos países, como o Brasil. Apesar do grande potencial comercial da pitaia, ainda são escassos os estudos de caracterização físico-química, compostos bioativos e de atividade antioxidante e enzimática dos seus frutos, principalmente considerando a espécie Hylocereus undatus. Neste trabalho, objetivou-se analisar as características físico-químicas, compostos bioativos, atividade antioxidante e enzimática de frutos da pitaia (Hylocereus undatus) em dois períodos (após a colheita = 45 dias após a antese e armazenamento por 12 dias = 57 dias após a antese), a fim de avaliar as características em dois períodos de comercialização. As análises realizadas foram: DL/DT (diâmetro longitudinal/transversal), massa fresca dos frutos, cor (casca e polpa), acidez titulável, sólidos solúveis, sólidos solúveis/acidez titulável, pH, lipídios, cinzas, açúcares redutores e totais, ácido ascórbico, compostos fenólicos, flavonoides amarelos, atividade antioxidante e enzimática. Dos parâmetros avaliados, as características físicas e lipídios não foram influenciados em decorrência ao armazenamento, entretanto as demais características químicas, atividade antioxidante e enzimática e compostos bioativos apresentaram diminuição conforme a armazenamento dos frutos decorrente a reações bioquímicas. Destacando os frutos com 45 dias, com maiores teores de antioxidantes, compostos bioativos, açúcares e acidez, ao qual indica frutos com qualidade e maior aceitabilidade dos consumidores decorrente ao maior conteúdo de compostos benéficos e essenciais ao consumo, além de ser de grande importância industrial.

Solanum americanum Mill. is a plant that belongs to the Solanaceae family, its respective ripe fruit is dark purple. Ripe S. americanum Mill. fruits were submitted to physicochemical characterisation, and their trans-resveratrol contents were quantified by high-performance liquid chromatography. Such determination was executed with fruits at different stages of ripeness and freeze-stored fruits as well. In natura ripe fruit pulp and peel presented average trans-resveratrol amounts of 1.07 and 0.7960 μg per gram of sample, respectively. These amounts are significantly higher when compared to freeze-stored fruit (0.1353 μg of trans-resveratrol per gram of sample) and to other berries. All ripe fruits showed significant amounts of total anthocyanins and total antioxidants. Thus, for the first time, trans-resveratrol has been identified and quantified in S. americanum Mill. fruit samples.

A cactácea pitaia, rica em nutrientes, ácidos graxos essenciais e antioxidante, apresenta vida de prateleira entre 6 a 8 dias, ao qual dificulta sua exportação. Este estudo teve como objetivo avaliar as características químicas e bioquímicas durante o armazenamento dos frutos com aplicação de revestimentos comestíveis e refrigeração. Os frutos foram selecionados quanto a injúrias e danos físicos, lavados e higienizados. A aplicação dos tratamentos foi realizada com gelatina e fécula, seguido de refrigeração em temperaturas de 8 ºC e 13 ºC. Os frutos foram armazenados durante 25 dias e avaliados quanto à açúcares totais e redutores (%), compostos fenólicos (AGE/mg), atividade antioxidante (% DPPH) e coloração. Os tratamentos aplicados não demonstraram influência sob os parâmetros avaliados. As temperaturas de refrigeração influenciaram na manutenção da qualidade dos frutos durante o período armazenado. O resultado da melhor temperatura para conservação dos frutos foi à 8 ºC.

O objetivo foi testar duas formulações de esfirra integral, uma com adição de aveia e outra sem adição de aveia, ambas com recheio de proteína texturizada de soja, além de realizar a pesquisa de mercado, identificar a porção recomendada, o valor calórico, o índice de aceitação e a análise sensorial. A análise sensorial foi realizada com 117 provadores não treinados, os atributos avaliados foram aroma, sabor, textura, aparência global e intenção de compra. O índice de aceitação para as duas formulações de esfirras foi maior que 70%, sendo que não foi observada a rejeição dos produtos avaliados. A composição centesimal demonstrou esfirras com bom aporte protéico e de fibra alimentar. Estudos sobre esfirras integrais são escassos, e este estudo demonstrou a oportunidade da junção de ingredientes com alegação funcional, os quais apresentam tanto aplicabilidade na fabricação dos produtos quanto benefício aos consumidores.

The local mode of a substitutional H− ion in KCN single crystals, the U-center, is measured in the three phases of the crystal. In the cubic phase the local mode peaks at 510 cm−1 with a linewidth of 120 cm−1. The higher energy phonon side band in the lower temperature phase is found to be displaced 80 cm−1 from the local mode peak. The low-temperature linewidth of the H local mode is approximately twice that of the D localized vibration. Also in opposition to the behavior in the alkali halides the linewidth keeps a high value even a t temperatures as low as 2 K. Die Lokalmode eines H−-Substitutionsions in KCN-Einkristallen, des U-Zentrums, wird in den drei Phasen des Kristalls gemessen. In der kubischen Phase erscheint die lokale Mode bei 510 cm−1 mit einer Linienbreite von 120 cm−1. Es wird gefunden, das die hoher energetische Phononenseitenbande in der Niedertemperaturphase um 80 cm−1 vom Maximum der Lokalmode verschoben ist. Die Tieftemperaturlinienbreite der H -Lokalmode ist etwa doppelt so gros wie die der D-Lokalschwingung. Im Gegensatz zum Verhalten der Alkalihalogenide behalt die Linienbreite sogar bei Temperaturen bis herunter zu 2 K einen hohen Wert.