Interakcije nekih plijesni i aflatoksinogenog soja Asspergillus flavus NRRL 3251

The objective of this study was to evaluate biotic interaction between some mould species and active producer of aflatoxin B1 Aspergillus flavus NRRL 3251, co-cultured in yeast-extract sucrose (YES) broth. Twenty-five mould strains of Alternaria spp., Cladosporium spp., Mucor spp., A. flavus and A. niger, used as biocompetitive agents, were isolated from outdoor and indoor airborne fungi, scrapings of mouldy household walls, and from stored and post-harvest maize. Aflatoxin B1 was extracted from mould biomasses with chloroform and detected using the multitoxin TLC method. The results confirm antagonistic interaction between all strains tested. With Alternaria spp. and Cladosporium spp., aflatoxin B1 production decreased 100 %, compared to detection in a single culture of A. flavus NRRL 3251 (Cmean=18.7 µg mL-1). In mixed cultures with Mucor spp., aflatoxin B1 levels dropped to (5.6-9.3) µg mL-1, and the inhibition was from 50 % to 70 %. Four of five aflatoxin non-producing strains of A. flavus interfered with aflatoxin production in mixed culture, and reduced AFB1 productivity by 100 %. One strain showed a lower efficacy in inhibiting AFB1 production (80 %) with a detectable amount of AFB1 3.7 µg mL-1 when compared to control. A decrease in toxin production was also observed in dual cultivation with A. niger strains. It resulted in 100 % reduction in three strains), 90 % reduction in one strain (Cmean=1.9 µg mL-1) and 80 % reduction in one strain (Cmean=3.7 µg mL-1) inhibition.Cilj rada bio je procijeniti biotske interakcije između sojeva različitih vrsta plijesni i kontrolnog soja Aspergillus flavus NRRL 3251, producenta aflatoksina B1 (AFB1). Inhibitorno djelovanje u miješanim kulturama na tvorbu AFB1 ispitano je na dvadeset pet sojeva Alternaria, Cladosporium, Mucor i Aspergillus vrsta izoliranih iz zraka, strugotina pljesnivih zidova te uskladištenog i prezimljenog kukuruza. Biosinteze su provedene u tekućoj hranjivoj podlozi s kvaščevim ekstraktom (YESbujon). Ekstrakcije AFB1 iz biomase izvršene su multitoksinskom metodom tankoslojne kromatografije. Rezultati biotskih interakcija pokazali su antagonistički odnos svih testiranih sojeva. Alternaria i Cladosporium vrste simultano inokulirane sporama A. flavus NRRL 3251 inhibirale su tvorbu AFB1 100 % u odnosu na dokazani toksin u kontrolnoj biosintezi (konc. 18,7 µg mL-1). U miješanim kulturama vrstama roda Mucor dokazane su padajuće koncentracije AFB1 (9,3 µg mL-1, 7,5 µg mL-1 i 5,6 µg mL-1), odnosno inhibicija tvorbe toksina 50 % do 70 %. Atoksinogeni sojevi A. flavus inhibirali su tvorbu AFB1 80 % (1 soj, konc. 3,7 µg mL-1) i 100 % (4 soja). Antagonističko djelovanje prema toksinogenom soju, smanjujući tvorbu AFB1 u rasponu 80 % do 100 % (konc. 1,9 µg mL-1 i 3,7 µg mL-1), dokazano je u uzgojnim biosintezama s A. niger

Biocontrol of Penicillium nordicum Growth and Ochratoxin A Production by Native Yeasts of Dry Cured Ham

Twelve yeast strains isolated from the surface of Italian typical dry-cured hams, belonging to D. hansenii, D. maramus, C. famata, C. zeylanoides and H. burtonii species, and previously selected for their ability to grow in dry-cured ham-like substrates, were screened for antagonistic activity against a toxigenic strain of P. nordicum and inhibition of ochratoxin A (OTA) biosynthesis. On average, yeast inhibitory activity was lowered by increasing fungal inoculum and enhanced by NaCl presence. In the assay conditions, H. burtonii and C. zeylanoides were the most effective, both in inhibiting P. nordicum growth and OTA production. D. hansenii was the species with the lowest inhibitory activity, especially in the absence of salt. OTA production dropped from the range < LOD − 5000 ppb in P. nordicum control plates to the range < LOD − 200 ppb in yeast-added plates. OTA production increased in the presence of NaCl in P. nordicum control plates, while salt enhanced inhibition against OTA production in yeast-added plates

The female menstrual cycle does not influence testosterone concentrations in male partners

<p>Abstract</p> <p>Background</p> <p>The time of ovulation has since long been believed to be concealed to male heterosexual partners. Recent studies have, however, called for revision of this notion. For example, male testosterone concentrations have been shown to increase in response to olfactory ovulation cues, which could be biologically relevant by increasing sexual drive and aggressiveness. However, this phenomenon has not previously been investigated in real-life human settings. We therefore thought it of interest to test the hypothesis that males' salivary testosterone concentrations are influenced by phases of their female partners' menstrual cycle; expecting a testosterone peak at ovulation.</p> <p>Methods</p> <p>Thirty young, healthy, heterosexual couples were recruited. During the course of 30-40 days, the women registered menses and ovulation, while the men registered sexual activity, physical exercise, alcohol intake and illness (confounders), and obtained daily saliva samples for testosterone measurements. All data, including the registered confounders, were subjected to multiple regression analysis.</p> <p>Results</p> <p>In contrast to the hypothesis, the ovulation did not affect the testosterone levels, and the resulting testosterone profile during the menstrual cycle was on the average flat. The specific main hypothesis, that male testosterone levels on the day of ovulation would be higher than day 4 of the cycle, was clearly contradicted by a type II error(β)-analysis (< 14.3% difference in normalized testosterone concentration; β = 0.05).</p> <p>Conclusions</p> <p>Even though an ovulation-related salivary testosterone peak was observed in individual cases, no significant effect was found on a group level.</p

Edible films and coatings as carriers of living microorganisms: a new strategy towards biopreservation and healthier foods

Edible films and coatings have been extensively studied in recent years due to their unique properties and advantages over more traditional conservation techniques. Edible films and coatings improve shelf life and food quality, by providing a protective barrier against physical and mechanical damage, and by creating a controlled atmosphere and acting as a semipermeable barrier for gases, vapor, and water. Edible films and coatings are produced using naturally derived materials, such as polysaccharides, proteins, and lipids, or a mixture of these materials. These films and coatings also offer the possibility of incorporating different functional ingredients such as nutraceuticals, antioxidants, antimicrobials, flavoring, and coloring agents. Films and coatings are also able to incorporate living microorganisms. In the last decade, several works reported the incorporation of bacteria to confer probiotic or antimicrobial properties to these films and coatings. The incorporation of probiotic bacteria in films and coatings allows them to reach the consumers gut in adequate amounts to confer health benefits to the host, thus creating an added value to the food product. Also, other microorganisms, either bacteria or yeast, can be incorporated into edible films in a biocontrol approach to extend the shelf life of food products. The incorporation of yeasts in films and coatings has been suggested primarily for the control of the postharvest disease. This work provides a comprehensive review of the use of edible films and coatings for the incorporation of living microorganisms, aiming at the biopreservation and probiotic ability of food products.Ana Guimaraes received support through grant SFRH/BD/ 103245/2014 from the Portuguese Foundation for Science and Technology (FCT). Luís Abrunhosa was supported by grant UMINHO/BPD/51/2015 from project UID/BIO/04469/2013 financed by FCT/MEC (OE). This study was supported by FCT under the scope of the strategic funding of UID/BIO/04469/2013 unit and COMPETE 2020 (POCI-01-0145-FEDER-006684), and of BioTecNorte operation (NORTE-01-0145-FEDER000004) funded by European Regional Development Fund under the scope of Norte2020 - Programa Operacional Regional do Norte. Vectors used in Figure were designed by Freepik.info:eu-repo/semantics/publishedVersio

Yeast biocontrol of grain spoilage moulds

The biocontrol yeast Pichia anomala J121 prevents mould spoilage by Penicillium roqueforti and prolongs the safe storage of moist cereal grain in malfunctioning airtight storage systems. P. anomala is naturally occurring on grain and is classified as safe, i.e. biosafety level 1 microorganism. Strain J121 does not grow above 37°C and is sensitive to commonly used antifungal drugs. The ability of P. anomala to prevent mould growth during 14 months of wheat grain storage was evaluated in outdoor silos with different air permeability. P. anomala rapidly consumed O2 leaking into the silo during the spring, and P. roqueforti did not grow in treatments inoculated with P. anomala. A connection between production of the ester ethyl acetate and biocontrol activity was found. The biocontrol effect was enhanced when complex medium or glucose was added to grain minisilos. The addition did not markedly influence yeast cell numbers, but products of glucose metabolism, ethyl acetate in particular and ethanol, increased. When a diploid and a haploid strain of Pichia anomala were tested at two water activities (aw) for biocontrol ability in grain minisilos, the two yeast strains grew and inhibited mould growth equally well and showed similar patterns of ethyl acetate production at the higher aw. However, at lower aw the growth, biocontrol performance and ethyl acetate production of the haploid strain were reduced. The biocontrol activity of an additional 57 yeast species was evaluated in grain minisilos. Most yeast species grew to levels comparable to that of P. anomala J121, but only six other species strongly inhibited P. roqueforti. The biocontrol activity of Candida fennica and Candida silvicultrix is reported for the first time. The ability of 27 yeast species to grow to high CFU values without inhibiting mold growth, and the increase in biocontrol activity after nutrient addition, indicates that nutrient competition is not the main reason for mould inhibition in the system. Instead, a combination of ethyl acetate production and rapid consumption of oxygen leaking into the system could be the main inhibitory mechanism

Fertility in Inflammatory Bowel Disease

Inflammatory bowel diseases (IBD) often present in adolescence or early adulthood and is thus frequently diagnosed in men and women in their reproductive age. Previous population-based studies of fertility in patients with IBD are scarce. From the Swedish National Patient Register (NPR) all patients diagnosed with IBD of fertile age between 1964–2014 were identified. Statistics Sweden identified a matched reference cohort (ratio 1:5) from the general population matched for sex, age and place of birth. Children born were identified through the Medical Birth Register and the Swedish Multigeneration Register. For subgroup analyses information about medication was collected through Medical Drug Register and information about socioeconomic status from Longitudinal Integrated Database for Health Insurance and Labour Market Studies. From the SWedish Inflammatory Bowel disease quality REGister (SWIBREG) a cohort of women with UC who underwent colectomy 2000–2020 was identified. Demographic data from SWIBREG and information from a study specific questionnaire regarding reproductive history and voluntary childlessness were analysed. From the NPR 27,331 women and 29,104 men with IBD were identified, corresponding to 272,793 matched individuals. The fertility rate in women with IBD was 1.52 (standard deviation [SD] 1.22) births per 1000 person-years, compared with 1.62 (SD 1.28) (p &lt;0.001) in the matched reference cohort. Fertility was negatively affected mainly in women with Crohn's disease (CD) and IBD-unclassified (IBD-U) and to a lesser extent in ulcerative colitis (UC). Disease activity, bowel resections and, in the case of CD, also perianal disease further adversely affected fertility. For women with UC and IBD-U, but not for women with CD, fertility improved throughout the study period. Contraceptive use was higher in female IBD patients, both before and after the diagnosis. In total 2,989 women underwent colectomy during the study period. Reconstruction with ileal pouch anal anastomosis (IPAA) and ileorectal anastomosis (IRA) was used to about the same extent in UC and IBD-U, although this was rare in CD. Compared with the matched reference cohort, women with IBD had lower fertility overall after colectomy (HR 0.65, CI 0.61–0.69), with least impact for operations that left the rectum intact (HR 0.79, CI 0.70–0.90). When the comparison was made within the group of patients undergoing colectomy, fertility in female patients remained nearly unaffected after IRA in all subtypes of IBD, but was impaired after IPAA, especially in UC (HR 0.67 CI 0.50–0.88), and after completion proctectomy in all subtypes of IBD (CD 0.61 CI 0.38–0.96), UC HR 0.65, CI 0.49–0.85 and IBD-U0.68, 0.55–0.85). The survey regarding reproductive behavior after colectomy was completed by 214 (73%) out of 294 eligible women identified in SWIBREG. The desire to have children was negatively affected by disease onset in 59% of the women, colectomy in 44% and by reconstruction in 37%. Altogether, 39% women with UC estimated that they chose to have fewer children in the end because of the disease, but only 10% expressed that the disease made them completely restrain from having children. On the contrary 37% of the women reported that they had experienced difficulties to conceive and 19% expressed that they could not conceive at all. Of the women undergoing reconstruction post colectomy, 37% reported that the choice of reconstruction method was influenced by their desire to have children. Difficulty conceiving was more commonly reported after reconstruction with IPAA (odds ratio [OR] 5.54) than IRA (OR 2.57). Men with IBD also had lower fertility rate compared with the matched reference population, although the impact on parity was limited; 1.28 (SD 1.27) versus 1.35 (SD 1.31) (p &lt; 0.001). Fertility in men was nevertheless impaired in all IBD subtypes. The disease severity measured as order of hospital admissions (UC and IBD-U), intensity of medical treatment (CD), and bowel surgery (IBD-U) were further associated with impaired fertility in men. In the 3,771 men undergoing colectomy during the study period, fertility was only marginally (HR 0.89, CI 0.85–0.94) impaired, regardless of reconstruction. In conclusion, women with IBD have only slightly reduced fertility rates compared with the matched reference population with some exceptions. In non-surgically treated patients, the impact was most pronounced in female patients with CD. Women post colectomy have a particularly marked impact on fertility independent of IBD subtype. Bowel reconstruction with IPAA and proctectomy had a pronounced negative impact on fertility, while fertility was not further affected after IRA. More than half of the women with UC post colectomy reported that developing UC has affected their desire to have children, but difficulty to conceiving is also commonly reported. The impact of IBD in men was only minor

Recurrent Volvulus of an Ileal Pouch Requiring Repeat Pouchopexy: A Lesson Learnt

Introduction. Restorative surgery for ulcerative colitis with ileal pouch anal anastomosis (IPAA) is frequently accompanied by complications. Volvulus of the ileal pouch is one of the most rarely reported late complications and to our knowledge no report exists on reoperative surgery for this condition. Case Report. A 58-year-old woman who previously had undergone restorative proctocolectomy due to ulcerative colitis with an IPAA presented with volvulus of the pouch. She was operated with a single row pouchopexy to the presacral fascia. Two months later she returned with a recurrent volvulus. At reoperation, the pouch was found to have become completely detached from the fascia. A new pexy was made by firmly anchoring the pouch with two rows of sutures to the presacral fascia as well as with sutures to the lateral pelvic walls. At follow-up after five months she was free of symptoms. Conclusion. This first report ever on reoperative surgery for volvulus of a pelvic pouch indicates that a single row pouchopexy might be insufficient for preventing retwisting. Several rows seem to be needed