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CRUE-CSIC (Acuerdos Transformativos 2022), Genital herpes is one of the most common sexually transmitted infections worldwide. It mainly affects women, as the rate of sexual transmission from male-to-female is higher than from female-to-male. The application of vaginal antivirals drugs could reduce the prevalence of genital herpes and prevent future infections. Layer-bylayer vaginal films were prepared by the solvent evaporation method using iota-carrageenan, hydroxypropyl methylcellulose and the polymethacrylates Eudragit® RS PO and Eudragit® S100, for the controlled release of acyclovir. The films were characterized by texture analysis and Raman spectroscopy. Swelling, mucoadhesion, and drug release studies were conducted in simulated vaginal fluid. The results show that Layer-by-Layer films exhibited adequate mechanical properties. The structuring of the layer-by-layer films allowed the controlled release of acyclovir and produced a prolonged mucoadhesion residence time of up to 192 h. The films formed in layer 2 by the combination of Eudragit® RS PO and S100 showed a controlled release of acyclovir for eight days, and adequate mechanical properties. These promising formulations for the prevention of genital herpes deserve further evaluation., Ministerio de Ciencia, Innovación y Universidades (España)/Fondo Europeo de Desarrollo Regional, Ministerio de Economía, Comercio y Empresa (España), Depto. de Farmacia Galénica y Tecnología Alimentaria, Depto. de Farmacología, Farmacognosia y Botánica, Fac. de Farmacia, TRUE, pub

Women are the most affected by genital herpes, which is one of the most common sexually transmitted infections, affecting more than 400 million people worldwide. The application of vaginal microbicides could provide a safe method of protection. Acyclovir is a safe and effective medication for vaginal administration, and numerous benefits have been observed in the treatment of primary or recurrent lesions due to genital herpes. Vaginal tablets based on a combination of the polymers iota-carrageenan and hydroxypropyl methylcellulose were developed for the controlled release of acyclovir. Swelling, mucoadhesion and drug release studies were carried out in simulated vaginal fluid. The tablets, containing a combination of iota-carrageenan and hydroxypropyl methylcellulose, have an adequate uptake of the medium that allows them to develop the precise consistency and volume of gel for the controlled release of acyclovir. Its high mucoadhesive capacity also allows the formulation to remain in the vaginal area long enough to ensure the complete release of acyclovir. These promising formulations for the prevention of genital herpes deserve further evaluation., Depto. de Farmacia Galénica y Tecnología Alimentaria, Fac. de Farmacia, TRUE, pub

Women are the most affected by genital herpes, which is one of the most common sexually transmitted infections, affecting more than 400 million people worldwide. The application of vaginal microbicides could provide a safe method of protection. Acyclovir is a safe and effective medication for vaginal administration, and numerous benefits have been observed in the treatment of primary or recurrent lesions due to genital herpes. Vaginal tablets based on a combination of the polymers iota-carrageenan and hydroxypropyl methylcellulose were developed for the controlled release of acyclovir. Swelling, mucoadhesion and drug release studies were carried out in simulated vaginal fluid. The tablets, containing a combination of iota-carrageenan and hydroxypropyl methylcellulose, have an adequate uptake of the medium that allows them to develop the precise consistency and volume of gel for the controlled release of acyclovir. Its high mucoadhesive capacity also allows the formulation to remain in the vaginal area long enough to ensure the complete release of acyclovir. These promising formulations for the prevention of genital herpes deserve further evaluation.

The objective of this work was to better understand the water permeation through edible films when water is either in its vapour or in its liquid state related to their physico-chemical properties. Film based on iota-carrageenans or sodium alginate, containing or not fat, and encapsulating or not an aroma compound (n-hexanal) have been prepared. Films were conditioned at three different relative humidities, 0%, 43% and 84%. The incorporation of the n-hexanal in both types of biopolymer modifies the mechanical properties of film matrix and has a synergistic effect when associated to fat. Increasing the moisture content induces film plasticization by decreasing the glass transition of the glycerol enriched phase. Only carrageenan displays similar value for the liquid water transfer rate whereas a discrepancy of the behaviour in contact of liquid or vapour was observed for the alginate-based film, confirming the Schroeder paradox due to swelling. (C) 2011 Elsevier Ltd. All rights reserved.

The objective of this work was to better understand the water permeation through edible films when water is either in its vapour or in its liquid state related to their physico-chemical properties. Film based on iota-carrageenans or sodium alginate, containing or not fat, and encapsulating or not an aroma compound (n-hexanal) have been prepared. Films were conditioned at three different relative humidities, 0%, 43% and 84%. The incorporation of the n-hexanal in both types of biopolymer modifies the mechanical properties of film matrix and has a synergistic effect when associated to fat. Increasing the moisture content induces film plasticization by decreasing the glass transition of the glycerol enriched phase. Only carrageenan displays similar value for the liquid water transfer rate whereas a discrepancy of the behaviour in contact of liquid or vapour was observed for the alginate-based film, confirming the Schroeder paradox due to swelling. (C) 2011 Elsevier Ltd. All rights reserved.

Disertační práce řeší problematiku nutriční charakteristiky mléka, v rámci které byly realizovány tři experimenty. První experiment řešil záměnu jadrné složky (kukuřice, pšenice, tritikale) krmné dávky dojnic s důrazem na zastoupení a obsah aminokyselin a mastných kyselin mléka. Druhý experiment se zabýval přídavkem zelené natě Bazalky pravé (Ocimum basilicum) do krmné dávky koz s důrazem na obsah senzoricky aktivních látek mléka. Třetí experiment zkoumal ovlivnění kvality vybraného mléčného výrobku (jogurtu) přídavkem sušiny, či hydrokoloidu (ióta-karagenanu). Změny ve složení mléka, resp. mléčných výrobků (jogurtů) byly sledovány pomocí chemických, chromatografických, spektro-skopických, texturních a senzorických metod. Zařazením obilnin (kukuřice, pšenice, tritikale) do krmné dávky dojnic nebyl ovlivněn obsah tuku mléka, vliv na obsah bílkoviny mléka mělo tritikale. Skladba aminokyselin i mastných kyselin neprokázala pšenici či tritikale jako plnohodnotnou náhradu za kukuřici. Avšak v obsahu mastných kyselin mléka byly prokázány statisticky významné rozdíly v obsahu kyseliny pentadekanové a palmitoolejové (P <= 0,05). Přídavek 0,1 kg zelené natě bazalky do krmné dávky koz neměl statisticky významný vliv na obsah celkové sušiny ani dusíkatých látek mléka, mléko však obsahovalo významně vyšší množství senzoricky aktivních látek 1-oktanolu, 1-undekanolu a 2-nonanonu (P <= 0,01, P <= 0,05). Všechny šarže jogurtů vykazovaly během skladování pokles hodnot pH a to do 20. dne. Bylo stanoveno pět volných mastných kyselin (C5:0, C13:0, C14:0, C16:0 a C18:1), jejichž obsah v průběhu skladování rostl. U sledovaných jakostních ukazatelů (pH, obsah volných mastných kyselin, analýza textury) nebyly nalezeny statisticky významné rozdíly mezi výrobky s přídavkem (ióta)-karagenanu a bez jeho přídavku s výjimkou volné kyseliny olejové, jejíž obsah byl ve vzorcích jogurtů s přídavkem (ióta)-karagenanu významně vyšší (P <= 0,05). Senzorické hodnocení preferuje přídavek (ióta)-karagen, This doctoral thesis resolves the nutritional characteristics of milk, within the framework of which three experiments were realized. The first experiment studied the substitution of hard fodder (e.g. maize, wheat, triticale) in dairy cow feed with an emphasis on amino acid and fatty acid content of the cow milk. The second experiment dealt with the addition of green basil leaves (Ocimum basilicum) to goat feed with an emphasis on the content of the sensory active compounds of goat milk. The third experiment investigated how the quality of a selected dairy product (i.e. yoghurt) was influenced by the addition of dried milk solids or hydrocolloids (i.e. iota-carrageenan). Changes in the composition of the milk, or respectively, dairy product (yoghurt), were tracked using chemical, chromatographic, spectroscopic, textural and sensory methods. The inclusion of grain (maize, wheat, triticale) into the dairy cows' feed did not influence the fat content of the milk; however, triticale did affect the milk's protein content. The composition of amino acid and fatty acid did not show that wheat or triticale were able to fully replace maize. Nevertheless, statistically significant differences were observed in the pentadecanoic and palmitooleic acid content in the milk (P <= 0.05). The addition of 0.1 kg of green basil tops into the goat feed had no statistically significant effect on the total solid and nitrogen content of this milk, but it did however contain significantly higher amounts of the sensory active compounds 1-octanol, 1-undecanol and 2-nonanone (P <= 0.01, P <= 0.05). The pH values of all batches of yoghurt samples declined throughout the storage period including up to the 20th day. It was established that five free fatty acids (C5:0, C13:0, C14:0, C16:0 and C18:1), whose content grew during the storage period. No statistically significant differences in the observed quality parameters (i.e. pH, free fatty acid content, texture analysis) were discovered between sa, Ústav analýzy a chemie potravin, obhájeno

Efekt 0,25 % w/w ?-karagenanu a ?-karagenanu na viskoelastické vlastnosti tavených sýrů byl studován použitím modelových vzorků obsahujících 40 % w/w sušiny a 45 a 50 % w/w tuku v sušině. Experimentální vzorky byly hodnoceny po 14 dnech skladování při teplotě 6?2 °C. Základní vlastnosti studovaných vzorků tavených sýrů (např. obsah sušiny a pH) se nelišily (P?0,05). Nebyl zde zaznamenán statisticky významný rozdíl v hodnotách elastického modulu G´ [Pa], ztrátového modulu G´´ [Pa] a tangent úhlu fázového posunu tan ? [-] při frekvenci 1 Hz mezi vzorky s ?-karagenanem přidávaným v práškové formě nebo ve formě vodné disperze (P?0,05)., The effect of 0.25% w/w ?-carrageenan and ? carrageenan on viscoelastic properties of processed cheese were studied using model samples containing 40% w/w dry matter and 45 and 50% w/w fat in dry matter. Experimental samples of processed cheese were evaluated after 14 days of storage at the temperature of 6?2 °C. Basic parameters of processed cheese samples under study (i.e. their dry matter content and pH) were not different (P?0.05). There were no statistically significant differences in values of storage modulus G´ [Pa], loss modulus G´´ [Pa] and tangent of phase shift angle tan ? [-] for the reference frequency of 1 Hz between processed cheese with ? carrageenan applied in the form of powder and in the form of aqueous dispersion (P?0.05). The addition of 0.25% w/w ? carrageenan and ? carrageenan (in the powder form) resulted in an increase in storage (G´) and loss (G´´) moduli and a decrease in values of tan ? (P<0.05).

Efekt 0,25 % w/w ?-karagenanu a ?-karagenanu na viskoelastické vlastnosti tavených sýrů byl studován použitím modelových vzorků obsahujících 40 % w/w sušiny a 45 a 50 % w/w tuku v sušině. Experimentální vzorky byly hodnoceny po 14 dnech skladování při teplotě 6?2 °C. Základní vlastnosti studovaných vzorků tavených sýrů (např. obsah sušiny a pH) se nelišily (P?0,05). Nebyl zde zaznamenán statisticky významný rozdíl v hodnotách elastického modulu G´ [Pa], ztrátového modulu G´´ [Pa] a tangent úhlu fázového posunu tan ? [-] při frekvenci 1 Hz mezi vzorky s ?-karagenanem přidávaným v práškové formě nebo ve formě vodné disperze (P?0,05)., The effect of 0.25% w/w ?-carrageenan and ? carrageenan on viscoelastic properties of processed cheese were studied using model samples containing 40% w/w dry matter and 45 and 50% w/w fat in dry matter. Experimental samples of processed cheese were evaluated after 14 days of storage at the temperature of 6?2 °C. Basic parameters of processed cheese samples under study (i.e. their dry matter content and pH) were not different (P?0.05). There were no statistically significant differences in values of storage modulus G´ [Pa], loss modulus G´´ [Pa] and tangent of phase shift angle tan ? [-] for the reference frequency of 1 Hz between processed cheese with ? carrageenan applied in the form of powder and in the form of aqueous dispersion (P?0.05). The addition of 0.25% w/w ? carrageenan and ? carrageenan (in the powder form) resulted in an increase in storage (G´) and loss (G´´) moduli and a decrease in values of tan ? (P<0.05).

The recently discovered isotropic/nematic phase transition in kappa-carrageenan was further examined by macroscopic observations and by NMR. A state diagram, which is the equivalent of a phase diagram but including also nonequilibrium states (in our case a gel), was established in the mixed salt solutions of NaI/CsI where the competition between phase separation and gelation could be studied. The phase boundaries of the nematic phase depended on molecular weight and ionic strength qualitatively as expected for a charged rigid polymer. From these data the persistence length of the kappa-carrageenan helix was estimated as 60-90 nm. The volume fraction of the nematic phase depended sensitively on the overall helical content. In coexisting phases, the helical content was larger in the nematic than in the isotropic phase.