Osteoprotective effects of kefir fortified with omega-3 and vitamin C in ovariectomized rats.

Nutritional interventions can be valuable for the prevention of postmenopausal osteoporosis. This study aimed to investigate the effects of kefir fortified with omega-3 and vitamin C on the bone and uterus parameters of ovariectomized rats. Seventy-seven female Sprague-Dawley rats were ovariectomized or sham-operated. The ovariectomized rats were assigned to six groups and received 1 ml/day of distilled water (OVX group), milk, kefir, kefir fortified with omega-3 fatty acids (kefir+ω3), kefir fortified with vitamin C (kefir+vit-C) or kefir fortified with omega-3 and vitamin C (kefir+ω3+vit-C) for 12 weeks. The sham group also received 1ml/day of distilled water. Subsequently, bone mineral content (BMC) and bone mineral density (BMD) of various bones were assessed. Femurs and uteri were harvested for bone ash analysis and histopathological examinations, respectively. Sera were analyzed for carboxy-terminal cross-linked telopeptide of type 1 collagen, procollagen type 1 amino-terminal propeptide, calcium, phosphorous, tumor necrosis factor-α (TNF-α) and total antioxidant capacity levels. Ovariectomy resulted in significant reduction in bone density (P<0.05). Kefir+ω3+vit-C significantly improved BMC of lumbar spine (0.699±0.027 g compared with 0.580±0.018 in the OVX group), and kefir, kefir+vit-C and kefir+ω3+vit-C significantly increased BMD of tibia (0.118±0.003 g/cm2, 0.119±0.001 and 0.120±0.004 compared with 0.102±0.005 in the OVX group). Moreover, ovariectomy markedly elevated TNF-α level, which was significantly reversed by kefir+ω3+vit-C. Significant atrophy of the uterus was observed following ovariectomy, although the uterus parameters did not change by any of the interventions. In conclusion, kefir fortified with omega-3 fatty acids and vitamin C may have protective effects against bone loss through suppressing inflammation.

Inhibition of histamine accumulation by novel histamine-degrading species of Staphylococcus sp. isolated from goats and sheep milk.

Histamine is an active amine compound that occurs in various fermented foods that may cause adverse effects on the human health. Certain microorganisms are able to degrade histamine by an oxidative deamination reaction. Therefore, the present study aimed to quantify histamine-forming and/or -degrading activity of the isolates derived from milk of goat and sheep herds, in Iran, by the capillary zone electrophoresis (CZE) method; and we evaluated the molecular characteristics of staphylococcal isolates. Among 243 staphylococcal isolates, 29 histamine-degrading bacteria were identified. One of these isolates, identified as Staph. epidermidis, No. 605, exhibited the highest activity compared to others, degrading available histamine to 58.33% within 24 h. By polymerase chain reaction (PCR) analysis, the isolate, No. 605 that exhibited remarkable histamine-degrading activity lacked the genes encoding coagulase and DNase, nor did it harbor any of the five classical enterotoxin genes. This is the first report to show that seven Staphylococcus species, including Staph. chromogenes, Staph. aureus, Staph. haemolyticus, Staph. epidermidis, Staph. pseudintermedius, Staph. agnetis, and Staph. hyicus, were able to degrade histamine, which were hitherto not known to have this capacity. Therefore, histamine-degrading activity is a definite criterion to introduce fermenting organisms able to decrease histamine content in different food products.

The Multitasking Surface Protein of Staphylococcus epidermidis: Accumulation-Associated Protein (Aap).

The stratum corneum is the outermost layer of the epidermis and is thus directly exposed to the environment. It consists mainly of corneocytes, which are keratinocytes in the last stage of differentiation, having neither nuclei nor organelles. However, they retain keratin filaments embedded in filaggrin matrix and possess a lipid envelope which protects the body from desiccation. Despite the desiccated, nutrient-poor, and acidic nature of the skin making it a hostile environment for most microorganisms, this organ is colonized by commensal microbes. Among the classic skin commensals are Propionibacterium acnes and coagulase-negative staphylococci (CoNS) with Staphylococcus epidermidis as a leading species. An as-yet-unanswered question is what enables S. epidermis to colonize skin so successfully. In their recent article, P. D. Fey and his colleagues (P. Roy, A. R. Horswill, and P. D. Fey, mBio 12:e02908-20, 2021, https://doi.org/10.1128/mBio.02908-20) have brought us one step closer to answering this question.

The Neuromodulator-Encoding sadA Gene Is Widely Distributed in the Human Skin Microbiome.

Trace amines (TA) are endogenously produced in mammals, have a low concentration in the central nervous system (CNS), but trigger a variety of neurological effects and intervene in host cell communication. It emerged that neurotransmitters and TA are produced also by the microbiota. As it has been shown that TA contribute to wound healing, we examined the skin microbiome of probands using shotgun metagenomics. The phyla Actinobacteria, Proteobacteria, Firmicutes, and Bacteroidetes were predominant. Since SadA is a highly promiscuous TA-producing decarboxylase in Firmicutes, the skin microbiome was specifically examined for the presence of sadA-homologous genes. By mapping the reads of certain genes, we found that, although there were less reads mapping to sadA than to ubiquitous housekeeping genes (arcC and mutS), normalized reads counts were still >1000 times higher than those of rare control genes (icaA, icaB, and epiA). At protein sequence level SadA homologs were found in at least 7 phyla: Firmicutes, Actinobacteria, Proteobacteria, Bacteroidetes, Acidobacteria, Chloroflexi, and Cyanobacteria, and in 23 genera of the phylum Firmicutes. A high proportion of the genera that have a SadA homolog belong to the classical skin and intestinal microbiota. The distribution of sadA in so many different phyla illustrates the importance of horizontal gene transfer (HGT). We show that the sadA gene is widely distributed in the human skin microbiome. When comparing the sadA read counts in the probands, there was no correlation between age and gender, but an enormous difference in the sadA read counts in the microbiome of the individuals. Since sadA is involved in TA synthesis, it is likely that the TA content of the skin is correlated with the amount of TA producing bacteria in the microbiome. In this way, the microbiome-generated TA could influence signal transmission in the epithelial and nervous system.

Dietary Intakes of Zinc, Copper, Magnesium, Calcium, Phosphorus, and Sodium by the General Adult Population Aged 20-50 Years in Shiraz, Iran: A Total Diet Study Approach.

In the present total diet study, the dietary intake of zinc (Zn), copper (Cu), magnesium (Mg), calcium (Ca), phosphorus (P), and sodium (Na) by healthy adults in Shiraz, Iran, was estimated from the foods as consumed. A total of 580 individual food items were collected, prepared, and pooled into 129 composite samples. The metal concentration was then evaluated using inductively coupled plasma-optical emission spectrometry. The mean intakes of Zn (12.92 mg/d), Cu (3.80 mg/d), and Mg (412.68 mg/d) exceeded the estimated average requirements (EARs), but they were well below the upper limits. A high prevalence of inadequate intake was observed for Ca (91.6%) and P (89.7%), which was mainly due to nutritionally imbalanced diets. Sodium intake for average and high consumers (97.5th percentile) was 123.6% and 237.8% of the tolerable upper intake level of 2300 mg/d, respectively, with 70% of the participants having intakes higher than this threshold value. Nutrition education, nutritional rehabilitation, Ca supplementation, food fortification, mandatory reduction of salt content in processed foods, and discretionary salt use (in home cooking or at the table) are among the possible strategies that can be adopted to combat the health problems.

Central Composite Design for Optimizing the Biosynthesis of Silver Nanoparticles using Plantago major Extract and Investigating Antibacterial, Antifungal and Antioxidant Activity.

Central composite design (CCD) was applied to optimize the synthesis condition of silver nanoparticles (AgNPs) using the extract of Plantago major (P. major) seeds via a low cost and single-step process. The aqueous seed extract was applied as both reducing element and capping reagent for green production of AgNPs. Five empirical factors of synthesis including temperature (Temp), pH, volume of P. major extract (Vex), volume of AgNO3 solution (VAg) and synthesis time were used as independent variables of model and peak intensity of Surface Plasmon Resonance (SPR) originated from NPs as the dependent variable. The predicted optimal conditions was determined to be: Temp = 55 °C, pH = 9.9,Vex = 1.5 mL, VAg = 30 mL, time = 60 min. The characterization of the prepared AgNPs at these optimum conditions was conducted by Fourier transform infrared spectroscopy (FTIR), dynamic light scattering (DLS), transmission electron microscopy (TEM) and X-ray diffraction (XRD) to determine the surface bio-functionalities. Bio-activity of these AgNPs against bacteria and fungi were evaluated based on its assay against Micrococcus luteus, Escherichia coli and Penicillium digitatum. Furthermore, antioxidant capacity of these NPs was checked using the ferric reducing antioxidant power (FRAP) assay.

Protective effects of synbiotic soymilk fortified with whey protein concentrate and zinc sulfate against bile duct ligated-induced hepatic encephalopathy.

AIM: This study aimed to compare the effects of synbiotic soymilk fortified with whey protein concentrate and zinc sulfate with lactulose on bile duct ligated-induced HE. BACKGROUND: Hepatic encephalopathy (HE) is seriously associated with neuromuscular and cognitive alterations. METHODS: Eighty-two Sprague Dawley rats were randomly assigned into seven groups (sham, bile duct ligation (BDL), BDL + lactulose, BDL + soymilk (SM), BDL + Synbiotic soymilk (SSM), BDL + SSM + whey protein concentrate (WPC), BDL + SSM + WPC + ZnSO4). Different SM products, lactulose, and normal saline were administered via oral gavage (2 mL/rat/day). The serum and liver markers as well as liver histopathology were assessed after 28 days. RESULTS: The SM products significantly reduced the serum alanine aminotransferase, albumin, and ammonia (P < 0.05). The levels of aspartate aminotransferase, endotoxin, and liver interleukin-6 improved significantly in all treatments, except for those receiving SM. SSM and SSM + WPC + ZnSO4 were the only effective products in reducing serum alkaline phosphatase (P < 0.05). Furthermore, the liver total antioxidant capacity was greater (P<0.05) in the SSM + WPC and SSM + WPC + ZnSO4 groups. The histopathological examinations confirmed the efficiency of all SM products in reducing liver fibrosis. Liver bile duct proliferation diminished only in the SSM + WPC and SSM + WPC+ ZnSO4 groups (P<0.05). CONCLUSION: This study showed the positive effects of different SM products, especially SSM + WPC and SSM + WPC + ZnSO4, on HE. Further studies are required to confirm our findings.

Antimicrobial spectrum activity of bacteriocinogenic Staphylococcus strains isolated from goat and sheep milk.

Bacteriocins have attracted great attention as potential alternatives to antibiotics and chemical food additives. In the present study, 243 Staphylococcus isolates from milk samples (n = 110) of goat and sheep herds located in Fars province, Iran, were screened for antimicrobial substance production. Twenty-eight isolates showed an antagonistic activity against the indicator strain Micrococcus luteus ATCC 4698. The susceptibility of all antimicrobial substances to proteolytic enzymes allowed us to consider them as bacteriocin-like inhibitory substances (BLIS). The term BLIS is applied to uncharacterized proteinaceous antimicrobials produced by gram-positive bacteria. Based on molecular identification methods, the isolates belonged to the species Staphylococcus chromogenes, Staphylococcus epidermidis, Staphylococcus haemolyticus, Staphylococcus pseudintermedius, Staphylococcus aureus, and Staphylococcus agnetis. Pulsed-field gel electrophoresis revealed a high level of genotype diversity among the Staph. chromogenes isolates. All of the isolates harbored nukA or bsaA2 genes, suggesting that their BLIS were related to nukacin or Bsa. The antimicrobial compounds from test strains were not effective against gram-negative pathogens, including Salmonella enterica serovar Typhimurium, Escherichia coli O157:H7, and Klebsiella pneumonia as well as the indicator mold Aspergillus fumigatus. All the gram-positive targets, including Bacillus cereus, Listeria monocytogenes, Enterococcus faecalis Ef37 (a tyramine-producer strain), Lactobacillus saerimneri 30a (a histamine-producer strain), and methicillin-resistant Staph. epidermidis, were inhibited by the Staph. chromogenes isolates. Staphylococcus haemolyticus 4S12 was able to inhibit the majority of gram-positive bacteria. Listeria monocytogenes strains were the only indicators sensitive to the antimicrobial agents produced by Staph. agnetis 4S97B. The other Staphylococcus strains were ineffective on all the organisms tested. Based on their inhibitory capacities, the BLIS produced by the Staph. chromogenes isolates seem to be interesting candidates for developing novel antimicrobial agents.

Heavy metals (Pb, Cd, Cu, Zn, Ni, Co) in leafy vegetables collected from production sites: their potential health risk to the general population in Shiraz, Iran.

Heavy metal contamination of vegetables is a great public health concern. One hundred samples of spinach, dill, cilantro, and cress from the production sites of Shiraz, Iran, and its outskirts were, therefore, examined for lead (Pb), cadmium (Cd), copper (Cu), zinc (Zn), nickel (Ni), and cobalt (Co) content. The potential health risks of these metals to local residents via the consumption of leafy vegetables were also estimated. The mean concentrations of Pb, Cd, Cu, Zn, Ni, and Co were 3.21, 0.28, 4.55, 40.44, 3.11, and 1.86 mg/kg dry weight, respectively. The Pb level exceeded the permissible limit of 0.3 mg/kg in 44.7% of vegetable samples. The other elements were, however, within FAO/WHO standards. The estimated daily intake (EDI) of Pb, Cd, Cu, Zn, Ni, and Co from leafy vegetables was 0.10, 0.01, 0.14, 1.26, 0.10, and 0.06 µg/kg body weight/day, respectively. At the mean and 97.5 percentile levels, all health risk index (HRI) values were less than the safe limit (< 1). Thus, within the area this study was focused on, leafy vegetables did not make a major contribution to the dietary intake of the elements which could be mainly attributed to the low vegetable consumption by the study population (20 g/day). Nevertheless, the lead content of the vegetables should be viewed with some concern. Regular monitoring of heavy metal contamination of foodstuff is recommended to control the sources of contaminants in the food chain.

The efficacy of probiotic supplementation in rheumatoid arthritis: a meta-analysis of randomized, controlled trials.

Probiotics are considered as -immunomodulatory agents; their efficacy as an adjunct therapy option for rheumatoid arthritis (RA), however, remains controversial. The main aim of the present meta-analysis, therefore, was to compare available data from the published randomized, controlled trials (RCTs) recruiting adults with RA which compared probiotics with placebo. The English literature search was performed using Ovid version of Medline, EmBase, Web of Science, and the Central Cochrane library through October 2016 and supplemented by hand searching reference lists. Among 240 citations identified, 4 RCTs (153 participants; 89% female) were included. All data were pooled using a standardized mean difference (SMD) with a 95% CI. Compared to the placebo, probiotics did not change the inflammatory parameters (erythrocyte sedimentation rate, tumor necrosis factor [TNF]-α, interleukin [IL]-1ß, IL-6, IL-10, and IL-12) and oxidative stress indices (total antioxidant capacity and malondialdehyde) significantly. The borderline significant reduction as a result of probiotic administration was only determined in C-reactive protein [SDM - 0.32 (95% CI - 0.65 to 0.00)]. Among disease activity indices (disease activity score [DAS], tender joint count, and swollen joint count), DAS showed a significant improvement following probiotic treatment with a SMD (95% CI) of - 0.58 (- 0.97 to - 0.19). The number of trials was too small to determine if a strain-, dose-, or duration-response effect was present. Probiotics seem to be less effective in RA; however, to reach a firm conclusion, we need further evidence.

Safety hazards in bacteriocinogenic Staphylococcus strains isolated from goat and sheep milk.

In this study, 28 bacteriocinogenic Staphylococcus strains isolated from goat and sheep milk were subjected to the PCR detection of enterotoxin genes (sea-see), enterotoxin-like toxin Q gene (selq), toxic shock syndrome toxin gene (tst1), and antibiotic resistance genes. They were also evaluated for phenotypic resistance against 10 antibiotics and hemolytic activity. The tyramine and histamine production was investigated using the agar plate assay and capillary zone electrophoretic analysis (CZE). Twenty-five isolates harbored at least one enterotoxin gene. The gene sec was the most frequent (89%). The gene tst1 was found in 84% of sec-positive isolates. The occurrence of antibiotic resistance genes was in the order of blaZ/tetK (100%), mecA/ermB (86%), ermC (50%), and tetM (18%). The genes ermA, aac(6')Ie-aph(2″)Ia, vanA, and vanB were absent in all the isolates. Nineteen isolates were phenotypically susceptible to all the antibiotics. The only isolate with phenotypic resistance to penicillin G and oxacillin was S. epidermidis 4S93 which had a different SmaI-PFGE profile from those of the other S. epidermidis strains. All the S. haemolyticus and S. pseudintermedius isolates were not susceptible to trimethoprim. Twenty-five isolates showed complete or partial hemolytic activity. None of the isolates was able to decarboxylate tyrosine, while CZE analysis revealed histamine formation activity in S. haemolyticus 4S12. The occurrence of safety risks in the isolates reinforces the need for regular monitoring of food-producing animals to mitigate the risks of multidrug resistant and zoonotic pathogens. Moreover, none of the isolates fulfilled the safety criteria to be used as starter cultures or biopreservatives.

Duplicate portion sampling gives the most accurate iron intake estimate: Implications for iron status of female students.

Iron deficiency (ID) is one of the most common nutritional problems in the developing world, affecting primarily women of childbearing age. Poor dietary iron intake is a major reason of ID. Accurate measurement of iron intake is of crucial importance to combat the problem. The daily dietary iron intake of 67 female students aged between 20-30 years (a mean BMI of 21.8±3.4 kg/m2) was evaluated using three assessment methods: atomic absorption spectrometry of 3-day food duplicate samples, and food composition tables (FCTs) in combination with either food frequency questionnaire (FFQ) or dietary records. Iron status was examined using hematological and biochemical tests. The dietary iron intake determined by duplicate portion sampling (DPS; 4.12±1.84 mg/day) was significantly lower than the FCT-based estimates (P<0.001), and it was less than » of the recommended dietary allowance of 18 mg/day. No significant correlation was found between DPS technique and FCT-based assessment methods. Fifty percent of the participants had small or depleted iron stores (serum ferritin< 30 ng/mL), but only 4.5% had ID anemia (serum ferritin< 12 ng/mL and hemoglobin<12 g/dL). Dietary iron intakes and FFQ-based intakes of vitamin C were not significantly correlated with all the investigated hematological parameters. In order to take some steps toward more practical approaches to combat this health problem, development of an accurate iron intake assessment seems to be the first priority. In this regard, improvement and validation of national FCTs would be a promising solution.

Daily dietary intakes of zinc, copper, lead, and cadmium as determined by duplicate portion sampling combined with either instrumental analysis or the use of food composition tables, Shiraz, Iran.

Estimation of essential and toxic element intakes is crucial to evaluate the risks of deficiency or toxicity. The purpose of this study was to investigate and also to compare the dietary intakes of zinc (Zn) and copper (Cu) by adults living in Shiraz, Iran, determined by two procedures: duplicate portion sampling of 21 hospital meals combined with either instrumental analysis (voltammetric measurement) or the use of food composition tables (FCTs). The level of exposure to lead (Pb) and cadmium (Cd) was evaluated as well. The daily Zn intakes of both methods were not significantly different and were higher than the RDA values except the value measured by the instrumental analysis which was lower than the RDA established for a male adult. Daily intake of Cu determined by instrumental analysis was significantly lower and closer to RDA for adults compared with the value estimated by FCTs. The dietary intakes of Pb and Cd were 313 and 61% of the respective provisional tolerable weekly intakes (PTWIs), respectively. The accuracy of two methods used for estimation of Zn intake was similar. In the case of Cu, the use of FCTs, in which the influence of environmental conditions and dietary habits of meal preparation is not taken into account, overestimated dietary intake. The risk of zinc deficiency was found in adult males. Moreover, the estimated intake of Pb, but not Cd, could be a cause of concern for Shiraz population. Thus, conducting regular periodic studies to assess the dietary intake of mentioned elements are recommended.