摘要:

Lactic acid‐producing bacteria (LAB) isolated from fowl, fish intestines and mushroom were identified and characterized with reference to the production of bacteriocins and its genetic markers. Among the isolated cultures, two isolate each ofLactobacillus caseissp casei C‐40 and M‐50,Pediococcus pentosaceusC‐6 and M‐10, andPediococcus acidilacticiC‐20 and F‐58 and one isolate ofPediococcussp. F‐7 were potent producers of bacteriocin active against related strains of LAB. With reference to the genetic characterization of bacteriocin production, the potent cultures appeared to posses either one or two plasmids of 4–8 Kb size and a megaplasmid. Plasmid curing of bacteriocinogenic strain ofLact. caseissp. casei C‐40 resulted in the loss of bacteriocin production and an altered pattern of sugar utilization. Antibiogram of bacteriocinogenic cultures of LAB and bacteriocin indicators was carried out to evaluate as a markers in genetic characterization. The bacteriocinogenic cultures were resistant to most of the antibiotics, particularly those belonging to the ß‐lactam and cephalosporin groups. Besides, most of these cultures were sensitive to 30 μg of chloramphenicol and 15 ng of erythromycin. The potential role of bacteriocinogenic LAB is significance in maintaining the intestinal environment, however; sensitive/resistance to antibiotics is to be viewed with concern as feeds do contain antibiotics.

ISSN:0890-5436    

DOI:10.1080/08905439909549966

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

We have established three clonal lines of oregano (Origanum vulgare) for the purpose of investigating the possible link betweende novosynthesis of proline and the phenylpropanoid pathway. We usedPseudomonasas inoculation in the otherwise sterile micropropagated oregano shoots to stimulate a defense response. Oregano clones, like other plants, carry out an elicitor‐mediated defense response by inducing the phenylpropanoid pathway. Free phenolics and rosmarinic acid are produced via this pathway. We measured free proline, rosmarinic acid, and free phenolics in oregano shoots. We found that the induced higher levels of rosmarinic acid in somePseudomonasinoculated clones and at several stages is often correlated to higher levels of proline in those same clones. We found no conclusive link between free phenolics and free proline levels. From this study clonal line 0–4 appeared to be the best line to investigate the role of proline‐linked pentose phospahte pathway in regulating rosmarinic acid synthesis.

ISSN:0890-5436    

DOI:10.1080/08905439909549967

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Because of expected nutritional, sensorical and health benefits, non‐thermal processing has the potential to satisfy the growing demand for minimally processed foods and can simultaneously provide safe and stable foods. Since the 60's the use of high intensity pulsed electric fields in food processing has repeatedly been demonstrated for e.g. pasteurization or cell permeabilization. The technical advance in the field of pulsed power equipment during the last years legitimates the approach of re‐considering some of these processes.

ISSN:0890-5436    

DOI:10.1080/08905439909549968

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The isolated fungus, designated as LB‐54, was found to be most suitable for the production of GLA due mainly to its high content of lipid, 20.73 % of dry cell weight and GLA of 14.68 % of total fatty acids. The strain LB‐54 was identified asMucorsp on the basis of morphological characteristics. The influence of different carbon and nitrogen sources, incubation time and growth temperature was investigated. Glucose and yeast extract were found to be the best carbon and nitrogen sources, respectively, in terms of GLA yield. The highest production of GLA (74 mg/1) was obtained from the LB‐54 strain after 5 days of incubation at 28°C in basal medium containing glucose (20 g/1) and yeast extract (10 g/1) following glucose addition (7 % w/v) and incubation for an additional 3 days at 12°C.

ISSN:0890-5436    

DOI:10.1080/08905439909549969

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

Lipase mediated interesterification of acylglycerols from corn oil with conjugated linoleic acid (CLA) was studied in several organic solvents. Two commercially available lipases, IM‐60 from Mucormieheiand Chirazyme L‐2 fromCandida antarcticabrought about greatest extents of interesterification. Hexane was the best solvent from the standpoint of both maximizing the reaction rate and the extent of interesterification.

ISSN:0890-5436    

DOI:10.1080/08905439909549970

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

摘要:

The effects of high hydrostatic pressure treatment (100 to 600 MPa) coupled with heat treatment (0 to 60 °C) on the inactivation of peroxidase (POD) and polyphenoloxidase (PPO) in red grapes (Vitus viniferd) have been studied. The examination of the complex interactions between pressure and temperature has been carried out using a central composite rotatable design (CCRD). The response surfaces show that the lowest activity of POD (55.75%) and PPO (41.86%) was found to be at 60 °C at 600 MPa and 100 MPa, respectively.

ISSN:0890-5436    

DOI:10.1080/08905439909549971

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor

ISSN:0890-5436    

DOI:10.1080/08905439909549965

出版商:Taylor & Francis Group    

年代:1999

数据来源: Taylor