23 research outputs found
Potential use of deodorised water extracts: polyphenol-rich extract of Thymus pannonicus All. as a chemopreventive agent
Deodorised water extracts of aromatic plants are obtained as by-products of essential oil isolation and usually discarded as waste. However, phytochemical composition of these extracts encourages their further utilization as food additives or functional food ingredients. In this study we investigated phytochemical composition, antioxidant and in vivo antiproliferative activity of deodorised water extract of Thymus pannonicus All. (DWE). HPLC analysis revealed rosmarinic acid (RA) (71.11 +/- 1.54 mg/g) as the most abundant constituent of the extract, followed by salvianolic acid H (14.83 +/- 0.79 mg/g, calculated as RA). DWE exhibited pronounced antioxidant activity in vitro, in FRAP and DPPH tests (FRAP value: 7.41 mmol Fe/g and SC50: 3.80 mu g/g, respectively). Using the model of Ehrlich carcinoma cells in mice that were treated with DWE prior, at the time, and after tumour cells implantation, the tumour growth suppression and redox status of malignant cells (i.e., activities of antioxidant enzymes, level of glutathione and intensity of lipid peroxidation) were followed. DWE applied as pretreatment caused disturbance of antioxidant equilibrium as well as apoptosis/necrosis of up to 90% EAC cells. Results obtained in the present study revealed chemopreventive potential and possibility of T. pannonicus DWE usage. High content of RA and other phenolic compounds explains, at least in part, the observed effects
Potential of lactic acid bacteria from Pico cheese for starter culture development
Autochthonous lactic acid bacteria may provide a means of promoting the quality and safety of traditional fermented food products, in particular, artisanal cheeses. Pico cheese is an artisanal, dairy specialty of the Azores in risk of disappearing. Efforts to maintain its quality to the requirements of the modern markets are, thus, necessary. Lactic acid bacteria were isolated from artisanal Pico cheese, identified by sequencing of the 16S rRNA gene, and their potential as starter cultures was evaluated by studying their acidification ability, enzymatic activities (caseinolysis, lipolysis and API-ZYM profile), diacetyl and expolysaccharide production, autolysis, antimicrobial activity against Listeria monocytogenes ATCC 7466, Escherichia coli ATCC 25922, Staphylococcus aureus ATCC 29523, Pseudomonas aeruginosa ATCC 27853 and Clostridium perfringens ATCC 8357, sensory evaluation of odour formation in milk, syneresis and firmness of the curd. Several of the studied lactic acid bacteria isolates showed interesting properties for practical application as starters in artisanal cheese production. The isolates with the highest number of positive traits and, therefore, the most promising for starter development were Lactococcus lactis ssp. lactis L1C21M1, Lactobacillus paracasei L1B1E3, Leuconostoc pseudomesenteroides L1C1E6, Lactobacillus casei L1A1E5 and L1C1E8
Silagem de resĂduos da filetagem de tilápia do nilo (Oreochromis niloticus), com ácido fĂłrmico - análise BromatolĂłgica, fĂsico-quĂmica e microbiolĂłgica Silage of tilapia (Oreochromis niloticus) filetage residues with formic acid Bromatological, phisico-chemical and microbiological analyses
O experimento avaliou o valor nutritivo da silagem ácida da filetagem da tilápia do Nilo (Oreochromis niloticus Linneaus, 1758), visando sua utilização em substituição Ă farinha de peixe na alimentação de organismo aquático. A silagem consistiu de resĂduos da filetagem de tilápia (carcaça) e 3% de ácido fĂłrmico, armazenada em temperatura ambiente (máxima mĂ©dia de 21,5ÂşC) e temperatura mĂnima mĂ©dia de 15ÂşC, por trinta dias, em baldes de polietileno com um orifĂcio, por onde os gases saiam. O pH foi monitorado no 1Âş, 15Âş e 30Âş dia. Foram realizadas análises microbiolĂłgicas para contagem total de microrganismos e coliformes a 35ÂşC e 45ÂşC. O pH apresentou mĂ©dia de 3,95 ao final dos 30 dias. Nas análises microbiolĂłgicas observou-se a ausĂŞncia de coliformes a 45ÂşC e, que a quantidade de microrganismos diminuiu gradativamente. Do ponto de vista microbiolĂłgico, a silagem ácida de resĂduo da filetagem de tilápia mostrou-se como alimento alternativo viável para a alimentação animal.<br>The experiment was carried out for evaluate the nutritional value of the silage of Nile tilapia (Oreochromis niloticus Linneaus, 1758) filetage residues with formic acid as a replace of fish meal in aquatic organisms feeding as protein source. The silage consisted of tilapia filetage residues (carcass) and 3% formic acid, and it was stored in environmental temperature with a maximum average of 21,5Âş C and a minimum average of 15 Âş C, during thirty days, in polyethylene pails with an orifice for the exhaustion of gases. The pH was monitored on the 1st, 15th and 30th day. The microbiological analyses were made for the total count of microorganisms and coliforms at 35Âş C and 45Âş C. The average pH was 3.95 at the end of 30 days. The microbiological analyses showed absence of coliformes at 45Âş C and a gradual reduction in the quantity of microorganisms. From the microbiological standpoint, the acid silage of tilapia residues was shown to be an alternative viable diet for animal feeding