Efficacy of gaseous ozone to counteract postharvest table grape sour rot.

This work aims at studying the efficacy of low doses of gaseous ozone in postharvest control of the table grape sour rot, a disease generally attributed to a consortium of non-Saccharomyces yeasts (NSY) and acetic acid bacteria (AAB). Sour rot incidence of wounded berries, inoculated with 8 NSYstrains, or 7 AAB, or 56 yeast-bacterium associations, was monitored at 25 °C up to six days. Sour rot incidence in wounded berries inoculated with yeast-bacterium associations resulted higher than in berries inoculated with one single NSY or AAB strain. Among all NSY-AAB associations, the yeast-bacterium association composed of Candida zemplinina CBS 9494 (Cz) and Acetobacter syzygii LMG 21419 (As) showed the highest prevalence of sour rot; thus, after preliminary in vitro assays, this simplified As-Cz microbial consortium was inoculated in wounded berries that were stored at 4 °C for ten days under ozone (2.14 mg m-3) or in air. At the end of cold storage, no berries showed sour-rot symptoms although ozonation mainly affected As viable cell count. After additional 12 days at 25 °C, the sour rot index of inoculated As-Cz berries previously cold-stored under ozone or in air accounted for 22.6 ± 3.7% and 66.7 ± 4.5%, respectively. Molecular analyses of dominant AAB and NSY populations of both sound and rotten berries during post-refrigeration period revealed the appearance of new strains mainly belonging to Gluconobacter albidus and Hanseniaspora uvarum species, respectively. Cold ozonation resulted an effective approach to extend the shelf-life of table grapes also after cold storage.

Randomised clinical trial: efficacy of Lactobacillus paracasei-enriched artichokes in the treatment of patients with functional constipation--a double-blind, controlled, crossover study.

BACKGROUND: The role of probiotics in the management of constipation is uncertain. AIMS: To evaluate the effects of probiotic-enriched artichokes on treatment preference, symptom profile and short-chain fatty acid (SCFA) production in constipated subjects when compared with ordinary artichokes. METHODS: Twenty constipated patients (3M/17F; 38.8 ± 14.4 years) were studied using a double-blind method and a computer-generated randomisation list. Each patient consumed 180 g per day of ordinary artichokes or artichokes enriched with Lactobacillus paracasei IMPC 2.1 for 15 days (daily dose of 2 × 10(10) CFU). Relief of symptoms was evaluated using a visual analogue scale. The stool consistency and symptom profile of patients were investigated using the Bristol stool form chart and the Gastrointestinal Symptom Rating Scale questionnaire (GSRS). SCFA production in faecal samples was evaluated using HPLC. RESULTS: Eighty per cent of patients preferred probiotic-enriched artichokes to ordinary ones (P = 0.011). Satisfactory relief of symptoms was significantly higher (P = 0.0014) during the probiotic-enriched artichoke period. Bristol chart cluster scores were significantly higher (3.3 ± 1.2, 2.9 ± 1.3 2.2 ± 1.2, baseline, ordinary artichokes and probiotic-enriched ones, respectively; P = 0.009) and GSRS constipation was significantly lower (13.9 ± 0.9, 10.2 ± 0.8, 8.3 ± 0.9; P = 0.032) in the probiotic group compared with the baseline. As for SCFA production, propionic acid was significantly higher (2.2 ± 1.4, 2.1 ± 1.53, 1.5 ± 1.2; P = 0.035) in the probiotic group compared with baseline. CONCLUSION: This trial shows a positive effect on symptoms in constipated patients after intake of probiotic-enriched artichokes.

Role of the probiotic strain Lactobacillus paracasei LMGP22043 carried by artichokes in influencing faecal bacteria and biochemical parameters in human subjects.

AIMS: To evaluate the positive influence of the probiotic strain Lactobacillus paracasei LMGP22043 carried by artichokes into the human gut with special reference to faecal bacterial balance, short-chain fatty acid concentrations and enzyme activities in a randomized, double-blind human trial in comparison with probiotic-free artichokes (control). METHODS: Twenty subjects were randomized into two groups, which consumed daily 180 g of the artichoke product (probiotic or control) during two 15-day study periods (periods 1 and 2) separated by a 15-day washout in a crossover manner. Faecal samples were subjected to microbiological and biochemical analyses, and a strain-specific PCR was performed to monitor the probiotic strain. RESULTS: The probiotic strain, transported by the vegetable matrix, transiently colonized the gut of 17/20 subjects (median 6·87 log CFU g⁻¹ faeces), antagonized Escherichia coli and Clostridium spp. and increased the genetic diversity of lactic population based on REP-PCR profiles, mainly after period 1. CONCLUSIONS: The probiotic L. paracasei LMGP22043 successfully colonized the human gut and positively influenced faecal bacteria and biochemical parameters. SIGNIFICANCE AND IMPACT OF THE STUDY: The association of the probiotic L. paracasei with a food carrier rich in fibre can represent a new strategy for favouring a daily supply of probiotics and attracting more consumers to vegetable food fortified with probiotic strains.

Molecular identification and typing of natural whey starter cultures and microbiological and compositional properties of related traditional Mozzarella cheeses.

Cell numbers of presumptive lactic acid bacteria varied markedly between 7 natural whey starter cultures (NWSC) used for producing traditional cows' milk Mozzarella cheeses in the Apulia region of Southern Italy. Taxonomic identification revealed a large diversity at species level, including mesophilic and thermophilic lactobacilli, lactococci, streptococci and enterococci. Randomly Amplified Polymorphic DNA (RAPD-PCR), analysis showed the biodiversity among the strains and, for lactobacilli, some relationships with provenience of the natural starter. Cell numbers of presumptive lactic acid bacteria in the corresponding Mozzarella cheeses were similar or higher than those found in the corresponding NWSC. RAPD-PCR analyses showed that most of the strains in cheese originated from the starter. The gross composition varied markedly between the 7 Mozzarella cheeses and ranged from 53-64% moisture, 17-23% protein, 13-20% fat and 0.50-1.61% salt. The values of pH for several samples were above 6.0. As shown by urea-PAGE of the pH 4.6-insoluble nitrogen fractions, cheese samples were characterized by differences in alpha(S1)- and beta-casein hydrolysis. Cheeses also differed with respect to secondary proteolysis as shown by Principal Component Analysis (PCA) of data from RP-HPLC of the pH 4.6-soluble, pH 4.6-70% ethanol-soluble and 70% ethanol-insoluble nitrogen fractions. These differences were attributed to the different microbial composition of the NWSC. Strain selection and optimization of a protocol for producing a natural whey starter culture to be used by dairy factories of the Apulia region appears to be a pre-requisite to standardize the major traits distinguishing this cheese variety.

Characterization of Italian cheeses ripened under nonconventional conditions.

Four Italian cheeses (Casciotta di Urbino, Barricato San Martino, Vento d'Estate, and Ubriaco di Raboso) nonconventionally ripened under different plant materials (walnut leaves, herbs, hay, and wine by-products, respectively) were compared for compositional, microbiological, biochemical, and volatile profile characteristics. Mean values for gross composition were rather similar. Because primary starters were not used for manufacture, the endogenous lactic acid bacteria were mainly present (7.0 to 9.0 log10 cfu/g). Except for Lactobacillus paracasei and Leuconostoc mesenteroides, which were commonly identified in 3 cheeses, Lactococcus lactis, Enterococcus sanguinicola, Lactobacillus brevis, Enterococcus durans/Enterococcus faecium, Lactobacillus plantarum, and Weissella cibaria/Weissella confusa were variously found in the 4 cheeses. Random amplification of polymorphic DNA-PCR analysis showed the biodiversity among the strains, and the species of lactobacilli were in part grouped according to their origin. As shown by the principal component analysis of reverse-phase fast protein liquid chromatography data for the pH 4.6-soluble fractions and by the determination of free AA, the secondary proteolysis of Barricato San Martino and Vento d'Estate mainly differed from the other 2 cheeses. Purge-and-trap and solid-phase microextraction were coupled with gas chromatography-mass spectrometry to determine volatile compounds. Vento d'Estate showed the highest levels of almost all chemical classes, and Casciotta di Urbino was characterized by a very low level of volatile components. Esters, ketones, and terpenes were the chemical classes that mainly differentiated the cheeses. Several volatile compounds seemed to be released directly from the plant materials used for ripening, especially terpenes for Vento d'Estate cheese. The lowest level of volatile free fatty acids was found in Casciotta d'Urbino, in which rennet paste was not used during manufacture. The highest concentration of free fatty acids, especially butyric and caproic acids, was found in Vento d'Estate cheese.

Comparison of the compositional, microbiological, biochemical, and volatile profile characteristics of nine Italian ewes' milk cheeses.

Nine Italian ewes' milk cheeses were compared for compositional, microbiological, biochemical, and volatile profile characteristics. Mean values for the gross composition were rather similar among cheeses. The lowest pH values were found for cheeses that used primary starters. At the end of ripening, cheeses made from raw milk contained >6.0 log10 cfu/g of nonstarter lactic acid bacteria. Several species of lactobacilli were identified, but Lactobacillus plantarum and Lactobacillus paracasei were dominant. Random amplified polymorphic DNA-PCR analysis showed the biodiversity among the strains, and in several cases a relationship with the cheese of provenance. Cheeses differed mainly for secondary proteolysis, as shown by the principal component analysis applied to reversed-phase fast protein liquid chromatography data of the pH 4.6-soluble fractions and by determination of the free AA. A total of 113 volatile components were identified in the Italian Pecorino cheeses by solid-phase microextraction coupled with gas chromatography-mass spectrometry analysis. The volatile profiles of the 9 cheeses differed significantly. Quantitatively, alcohols were the most abundant chemical class for some cheeses, whereas ketones were the most abundant for other cheeses. Esters and carboxylic acids were largely found. Specific volatile components seemed to distinguish specific cheeses.

Peripheral neuropathy associated with ischemic vascular disease of the lower limbs.

This paper deals with the possible identification of somatic and autonomic nerve damage in patients with peripheral obliterative arterial disease (POAD) at different stages of the disease, with a well-reproducible technique like electroneurographic evaluation of nerve conduction. In 64 patients with intermittent claudication, 19 patients with pain at rest, and 7 patients with trophic ulcers, electroneurographic evaluation of motor (tibial and peroneal) and sensory (superficial peroneal and sural) nerve conduction was performed. The median nerve (motor and sensory) was used as control. A severe impairment of sural and superficial peroneal nerve velocities was evident in many claudicant patients and in all patients with pain at rest and trophic ulcers, with a progression in the conduction abnormalities in advanced stages of the disease. Motor nerve conduction showed only minor reductions in patients with claudication and pain at rest, although some of them did show very poor velocity values. In 21 patients with intermittent claudication and sensory nerve abnormalities, the autonomic fibers activity, evaluated by the skin sympathetic response (SSR) test, was significantly depressed, thus suggesting an involvement of the local autonomic system in the ischemic disease. A correlation exists between the severity of the somatic nerve damage and the stage of the vascular insufficiency. However, in the group of claudicant patients, the evidence of similar ischemic threshold (claudication distance) may be associated with a marked difference in the amount of somatic nerve damage. The somatic and autonomic nerve alterations may play a relevant role in the progression of the disease toward critical limb ischemia.