A Microbial Co-Culturing System for Producing Cellulose-Hyaluronic Acid Composites

In this study, a co-culture system combining bacterial cellulose (BC) producers and hyaluronic acid (HA) producers was developed for four different combinations. AAB of the genus Komagataeibacter sp. and LAB of the Lactocaseibacillus genus were used to produce BC and HA, respectively. Fourier-transform infrared spectroscopy, scanning electron microscopy, and X-ray diffraction were used to investigate changes in BC-HA composites chemical and morphological structure. Water absorption, uptake, and antibacterial properties were also tested. Outcomes highlighted a higher bacterial cellulose yield and the incorporation of hyaluronic acid into the composite. The presence of hyaluronic acid increased fiber dimension-nearly doubled for some combinations-which led to a decreased crystallinity of the composites. Different results were observed based on the BC producer and HA producer combination. However, water holding capacity (WHC) in all the samples improved with the presence of HA, while water uptake worsened. A thymol-enriched BC-HA composite showed high antibacterial activity against Escherichia coli DSM 30083(T) and Staphylococcus aureus DSM 20231(T). Results could contribute to opening new applications in the cosmetics or pharmaceutical fields

Homogeneity of Interspecific Hybrids Between Saccharomyces cerevisiae and Saccharomyces uvarum by Phenotypic and Transcriptional Analysis

Oenological traits, such as temperature profile and production of certain metabolites, were tested for four interspecifc hybrids obtained by"spore to spore" crossing between Saccharomyces cerevisiae and Saccharomyces uvarum strains and uniformity of their inheritance was found. PCR/RFLP analysis of ITS regions was carried out to confirm the hybrid nature of the strains. They showed an additive profile with five bands of the respective 325, 230, 170 and 125 bp. Finally gene expression study was performed by comparative DNA macroarray analysis of the hybrids and the preliminary results showed that the global gene expression patterns of hybrids are remarkably similar to one another. In conclusion, the data obtained by two different approaches, such as metabolic and transcriptomic strategies, suggest a large degree of homogeneity among interspecific hybrids between S. cerevisiae and S. uvarum. Moreover, the uniformity of F1 hybrids advises that the oenological trait inheritance mechanism is highly constant and reproducible

Leuconostoc performance in soy-based fermentations – Survival, acidification, sugar metabolism, and flavor comparisons

Leuconostoc spp. is often regarded as the flavor producer, responsible for the production of acetoin and diacetyl in dairy cheese. In this study, we investigate seven plant-derived Leuconostoc strains, covering four species, in their potential as a lyophilized starter culture for flavor production in fermented soy-based cheese alternatives. We show that the process of lyophilization of Leuconostoc can be feasible using a soy-based lyoprotectant, with survivability up to 63% during long term storage. Furthermore, the storage in this media improves the subse-quent growth in a soy-based substrate in a strain specific manner. The utilization of individual raffinose family oligosaccharides was strain dependent, with Leuconostoc pseudomesenteroides NFICC99 being the best consumer. Furthermore, we show that all investigated strains were able to produce a range of volatile flavor compounds found in dairy cheese products, as well as remove certain dairy off-flavors from the soy-based substrate like hexanal and 2-pentylfuran. Also here, NFICC99 was strain producing most cheese-related volatile flavor com-pounds, followed by Leuconostoc mesenteroides NFICC319. These findings provide initial insights into the development of Leuconostoc as a potential starter culture for plant-based dairy alternatives, as well as a promising approach for generation of stable, lyophilized cultures

Acetic Acid Bacteria: Physiology and Carbon Sources Oxidation

Acetic acid bacteria (AAB) are obligately aerobic bacteria within the family Acetobacteraceae, widespread in sugary, acidic and alcoholic niches. They are known for their ability to partially oxidise a variety of carbohydrates and to release the corresponding metabolites (aldehydes, ketones and organic acids) into the media. Since a long time they are used to perform specific oxidation reactions through processes called “oxidative fermentations”, especially in vinegar production. In the last decades physiology of AAB have been widely studied because of their role in food production, where they act as beneficial or spoiling organisms, and in biotechnological industry, where their oxidation machinery is exploited to produce a number of compounds such as l-ascorbic acid, dihydroxyacetone, gluconic acid and cellulose. The present review aims to provide an overview of AAB physiology focusing carbon sources oxidation and main products of their metabolism

The risk stratification of adverse neonatal outcomes in women with gestational diabetes (STRONG) study

Aims: To assess the risk of adverse neonatal outcomes in women with gestational diabetes (GDM) by identifying subgroups of women at higher risk to recognize the characteristics most associated with an excess of risk. Methods: Observational, retrospective, multicenter study involving consecutive women with GDM. To identify distinct and homogeneous subgroups of women at a higher risk, the RECursive Partitioning and AMalgamation (RECPAM) method was used. Overall, 2736 pregnancies complicated by GDM were analyzed. The main outcome measure was the occurrence of adverse neonatal outcomes in pregnancies complicated by GDM. Results: Among study participants (median age 36.8 years, pre-gestational BMI 24.8 kg/m2), six miscarriages, one neonatal death, but no maternal death was recorded. The occurrence of the cumulative adverse outcome (OR 2.48, 95% CI 1.59–3.87), large for gestational age (OR 3.99, 95% CI 2.40–6.63), fetal malformation (OR 2.66, 95% CI 1.00–7.18), and respiratory distress (OR 4.33, 95% CI 1.33–14.12) was associated with previous macrosomia. Large for gestational age was also associated with obesity (OR 1.46, 95% CI 1.00–2.15). Small for gestational age was associated with first trimester glucose levels (OR 1.96, 95% CI 1.04–3.69). Neonatal hypoglycemia was associated with overweight (OR 1.52, 95% CI 1.02–2.27) and obesity (OR 1.62, 95% CI 1.04–2.51). The RECPAM analysis identified high-risk subgroups mainly characterized by high pre-pregnancy BMI (OR 1.68, 95% CI 1.21–2.33 for obese; OR 1.38 95% CI 1.03–1.87 for overweight). Conclusions: A deep investigation on the factors associated with adverse neonatal outcomes requires a risk stratification. In particular, great attention must be paid to the prevention and treatment of obesity

Quality of life in liver transplant recipients during the Corona virus disease 19 pandemic: A multicentre study

Background: Liver transplant recipients require specific clinical and psychosocial attention given their frailty. Main aim of the study was to assess the quality of life after liver transplant during the current pandemic. Methods: This multicentre study was conducted in clinically stable, liver transplanted patients. Enrollment opened in June and finished in September 2021. Patients completed a survey including lifestyle data, quality of life (Short Form health survey), sport, employment, diet. To examine the correlations, we calculated Pearson coefficients while to compare subgroups, independent samples t-tests and ANOVAs. To detect the predictors of impaired quality of life, we used multivariable logistic regression analysis. Results: We analysed data from 511 patients observing significant associations between quality of life’s physical score and both age and adherence to Mediterranean diet (p <.01). A significant negative correlation was observed between mental score and the sedentary activity (p <.05). Female patients scored significantly lower than males in physical and mental score. At multivariate analysis, females were 1.65 times more likely to report impaired physical score than males. Occupation and physical activity presented significant positive relation with quality of life. Adherence to Mediterranean diet was another relevant predictor. Regarding mental score, female patients were 1.78 times more likely to show impaired mental score in comparison with males. Sedentary activity and adherence to Mediterranean diet were further noteworthy predictors. Conclusions: Females and subjects with sedentary lifestyle or work inactive seem to show the worst quality of life and both physical activity and Mediterranean diet might be helpful to improve it

Role of microbial collections in the selection of starter cultures

The aim of this study was to characterize, through a polyphasic approach, a pool of 27 strains of lactic acid bacteria (genus Lactobacillus), isolated from salami and deposited in the Unimore (University of Modena and Reggio Emilia) Microbial Culture Collection (UMCC). Moreover, 15 selected strains have been used for a preliminary technological screening in order to implement starter cultures suitable for the production of sausages. The genetic improvement programmes and the selection of starter cultures suitable for specific fermentation processes are some of the main activities of UMCC. As well as the preservation of characterized microbial cultures, UMCC manages the cataloging and sharing of the information on the strains collected by transferring and updating the biological data in an online public database (http://biolomics.umcc.unimore.it)

CALCULATION OF THE FREEZING POINT OF GELATO MIXTURE

Explaination of the formula reported by Leighton et al (1927) for the calculation of the gelato mixture freezing point (FP). FP (°C) = Y + F2 where: Y is the sugars' content and type; F2 is the salts' content

I microrganismi dell'aceto balsamico. Atti convegno:"anche la tradizione va studiata" ricerche preliminari per l'individuazione di starter per l'Aceto Balsamico Tradizionale.

Il ruolo e l'importanza dei microrganismi sulla qualità dell'aceto balsamico tradizionale