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Traditional cheesemaking processes often involve backslopping practice. However, over successive inoculations, acidification deficiencies may arise. In such cases, adding a starter is recommended to restore the ecosystem stability. This study examines the impact of an autochthonous starter composed of three Lactococcus lactis strains on a raw goat milk microbial community during their evolution. Bacterial composition and technological features (acidification and aroma) were analyzed during communities' evolution over 800 generations. 16S rRNA gene metabarcoding showed that Lactococcus lactis strains predominated. The raw goat milk community acidification capacities varied early in the evolution and then remained stable. Adding the L. lactis starter to this community stabilized the ecosystem from the beginning of the evolution. The acetoin production was associated with the starter presence, consistent with the establishment of the diacetylatis biovar strain from the starter in the raw goat milk community throughout the evolution. Increased or decreased production of some volatile organic compounds when the starter was added revealed a specific aroma footprint due to interactions between the two communities. This study showed that adding a starter could help to achieve the maximum acidification rate from the early inoculation cycles and could significantly modify the aroma profile during long-term backslopping., Competing Interests: Declaration of competing interest The authors of the manuscript “Interaction between a Lactococcus lactis autochthonous starter and a raw goat milk microbial community during long-term backslopping” submitted at Food Microbiol. have no conflict of interest to declare., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

At over 200 years, the maximum lifespan of the bowhead whale exceeds that of all other mammals. The bowhead is also the second-largest animal on Earth, reaching over 80,000 kg 1 . Despite its very large number of cells and long lifespan, the bowhead is not highly cancer-prone, an incongruity termed Peto's Paradox 2 . This phenomenon has been explained by the evolution of additional tumor suppressor genes in other larger animals, supported by research on elephants demonstrating expansion of the p53 gene 3-5 . Here we show that bowhead whale fibroblasts undergo oncogenic transformation after disruption of fewer tumor suppressors than required for human fibroblasts. However, analysis of DNA repair revealed that bowhead cells repair double strand breaks (DSBs) and mismatches with uniquely high efficiency and accuracy compared to other mammals. The protein CIRBP, implicated in protection from genotoxic stress, was present in very high abundance in the bowhead whale relative to other mammals. We show that CIRBP and its downstream protein RPA2, also present at high levels in bowhead cells, increase the efficiency and fidelity of DNA repair in human cells. These results indicate that rather than possessing additional tumor suppressor genes as barriers to oncogenesis, the bowhead whale relies on more accurate and efficient DNA repair to preserve genome integrity. This strategy which does not eliminate damaged cells but repairs them may be critical for the long and cancer-free lifespan of the bowhead whale., Competing Interests: Competing interests The authors declare no competing interests.

Background: The Finnish Geriatric Intervention Study to Prevent Cognitive Impairment and Disability (FINGER) showed cognitive benefits from a multidomain lifestyle intervention in at-risk older people. The LipiDiDiet trial highlighted benefits of medical food in prodromal Alzheimer's disease (AD). However, the feasibility and impact of multimodal interventions combining lifestyle with medical food in prodromal AD is unclear., Methods: MIND-AD mini was a 6-month multinational (Sweden, Finland, Germany, France) proof-of-concept randomized controlled trial (RCT). Participants were 60-85 years old, had prodromal AD (International Working Group-1 criteria), and vascular/lifestyle risk factors. The parallel-group RCT had three arms: multimodal lifestyle intervention (nutritional guidance, exercise, cognitive training, vascular/metabolic risk management and social stimulation); multimodal lifestyle intervention + medical food (Fortasyn Connect); and regular health advice/care (control). Participants were randomized 1:1:1 (computer-generated allocation at each site). Outcome evaluators were blinded to randomization. Primary outcome was feasibility of the multimodal intervention, evaluated by recruitment rate during a 6-month recruitment phase, overall adherence in each intervention arm, and 6-month retention rate. Successful adherence was pre-specified as attending ≥ 40% of sessions/domain in ≥ 2/4 domains (lifestyle intervention), and consuming ≥ 60% of the medical food (lifestyle intervention + medical food). The secondary outcomes included adherence/participation to each intervention component and overall adherence to healthy lifestyle changes, measured using a composite score for healthy lifestyle. Cognitive assessments were included as exploratory outcomes, e.g. Clinical Dementia Rating scale., Results: During September 2017-May 2019, 93 individuals were randomized (32 lifestyle intervention, 31 lifestyle + medical food, and 30 control group). Overall recruitment rate was 76.2% (64.8% during the first 6 months). Overall 6-month retention rate was 91.4% (lifestyle intervention 87.5%; lifestyle + medical food 90.3%; control 96.7%). Domain-specific adherence in the lifestyle intervention group was 71.9% to cognitive training, 78.1% exercise, 68.8% nutritional guidance, and 81.3% vascular risk management; and in the lifestyle + medical food group, 90.3% to cognitive training, 87.1% exercise, 80.7% nutritional guidance, 87.1% vascular risk management, and 87.1% medical food. Compared with control, both intervention arms showed healthy diet improvements (β Lifestyle×Time  = 1.11, P = 0.038; β Lifestyle+medical food×Time  = 1.43, P = 0.007); the lifestyle + medical food group also showed vascular risk reduction (P = 0.043) and less cognitive-functional decline (P < 0.05, exploratory analysis). There were 5 serious adverse events (control group: 1; lifestyle intervention: 3; lifestyle + medical food: 1) unrelated to interventions., Conclusions: The multidomain lifestyle intervention, alone or combined with medical food, had good feasibility and adherence in prodromal AD. Longer-term cognitive and other health benefits should be further investigated in a larger-scale trial., Trial Registration: ClinicalTrials.gov NCT03249688., (© 2024. The Author(s).)

HIV is highly prevalent in men who have sex with men (MSM) in West Africa. Many MSM in the region also have sex with women (MSMW). Accordingly, they are a potential bridge subpopulation for HIV transmission to women. We aimed to evaluate the proportions and characteristics of West African MSMW at high behavioral risk of acquiring HIV from male partners and transmitting it to female partners (HBRMF). The cohort ANRS-12324 CohMSM Study included 630 HIV-negative MSM in Burkina Faso, Cote d'Ivoire, Mali, and Togo. Among MSMW (i.e., with ≥ 1 female partner) in the cohort, HBRMF was identified using trajectory models based on seven at-risk sexual practices with male and female partners, including inconsistent condom use, multiple partnerships, and receptive same-sex anal intercourse. To assess the relevance of using trajectory models, we compared the proportions of participants who seroconverted during the cohort follow-up among those at HBRMF and those not at HBRMF. Factors associated with HBRMF were identified using a generalized estimation equation logistic regression model accounting for longitudinal data. Approximately half (47%) of the 304 MSMW (22% of all CohMSM study participants) were at HBRMF. This group accounted for 75% of the 28 HIV seroconversions observed during follow-up (p = 0.001). HBRMF was positively associated with being aged < 25 years (aOR 95% CI 1.67 [1.23-2.27]), being sexually attracted only to men (1.97 [1.38-2.78]), feelings of loneliness (1.92 [1.38-2.65]), and homonegative violence score (1.22 [1.05-1.41]). HBRMF was negatively associated with having had both stable and casual female partners in the previous 6 months (0.34 [0.20-0.60] vs. only a stable female partner). HBRMF tended to be negatively associated with having ≥ 4 sexual intercourses with female partners in the previous four weeks (0.54 [0.27-1.06] vs. no intercourse). Establishing official relationships with women might be a strategy for young and/or stigmatized MSMW to comply with social pressure to display a heterosexual lifestyle. However, this seems to increase the risk of HIV transmission to female partners. In the present study, almost half of MSMW were at HBRMF. This result stresses the need to adapt HIV research and prevention to MSMW and their female partners., (© 2023. The Author(s).)

The responses of various microbial populations to modifications in the physicochemical properties of a food matrix, as well as interactions between these populations already present, are the main factors that shape microbial dynamics in that matrix. This work focused on the study of microbial dynamics during labneh Ambaris production, a traditional Lebanese concentrated fermented goat milk made in jars during 3 months. This was assessed in two earthenware jars at a production facility. DNA metabarcoding of the ITS2 region as well as the V3-V4 region of the 16S rRNA gene was used to characterize the fungal and bacterial communities, respectively. Viable bacterial isolates were also identified by Sanger sequencing of the V1-V4 region of the 16S rRNA gene. Our results showed that the dominant microorganisms identified within labneh Ambaris ( Lactobacillus kefiranofaciens , Lentilactobacillus kefiri , Lactococcus lactis , Geotrichum candidum , Pichia kudriavzevii and Starmerella sp.) settle early in the product and remain until the end of maturation with varying abundances throughout fermentation. Microbial counts increased during early fermentation stage, and remained stable during mid-fermentation, then declined during maturation. While microbial compositions were globally comparable between the two jars during mid-fermentation and maturation stages, differences between the two jars were mainly detected during early fermentation stage (D0 until D10). No significant sensorial differences were observed between the final products made in the two jars. Neither coliforms nor Enterobacteriaceae were detected in their viable state, starting D7 in both jars, suggesting the antimicrobial properties of the product.

Labneh Ambaris is a traditional Lebanese dairy product typically made using goat milk in special earthenware jars. Its production is characterized by the regular additions of milk and coarse salt, all while draining the whey throughout a process that lasts for a minimum of 2 mo. In this study, 20 samples of labneh Ambaris, all produced by spontaneous fermentation, were studied. They were collected at the end of fermentation from different regions in Lebanon. Physicochemical and sensory properties were studied and microbial diversity was analyzed using culture-dependent and independent techniques. The V3-V4 region of the 16S rRNA gene and the ITS2 region were sequenced by DNA metabarcoding analyses for the identification of bacteria and yeast communities, respectively. Out of 160 bacterial and 36 fungal taxa, 117 different bacterial species and 24 fungal species were identified among all labneh Ambaris samples studied. The remaining ones were multi-affiliated and could not be identified at the species level. Lactobacillus was the dominant bacterial genus, followed by Lentilactobacillus, Lactiplantibacillus, Lacticaseibacillus, and Lactococcus genera, whereas Geotrichum and Pichia were the dominant fungal genera. The 20 samples tested had varying levels of salt, protein, and fat contents, but they were all highly acidic (mostly having a pH < 4). According to the sensory scores generated by classical descriptive analysis, all samples were described as having basic similar characteristics such as goat smell and flavor, but they could be differentiated based on various intensities within the same descriptors like salty and acidic. This work could be considered as a base toward obtaining a quality label for labneh Ambaris., (The Authors. Published by Elsevier Inc. and Fass Inc. on behalf of the American Dairy Science Association®. This is an open access article under the CC BY license (http://creativecommons.org/licenses/by/4.0/).)

Labneh Ambaris is a traditional Lebanese dairy product traditionally made using raw goat's milk in earthenware jars, but recently the use of artisanally pasteurized milk was introduced for safety reasons. In this study, 12 samples of labneh Ambaris were studied, six made using raw goat's milk and six others using artisanally pasteurized goat's milk. These samples were collected during fermentation and their microbial compositions were analyzed. The 16S V3-V4 and the ITS2 regions of the rDNA were sequenced by DNA metabarcoding analyses for the identification and comparison of bacterial and fungal communities, respectively. The samples had high microbial diversity but differences in samples microbiota were unrelated to whether or not milk was pasteurized. The samples were consequently clustered on the basis of their dominant bacterial or fungal species, regardless of the milk used. Concerning bacterial communities, samples were clustered into 3 groups, one with a higher abundance of Lactobacillus helveticus , another with Lactobacillus kefiranofaciens as the dominant bacterial species, and the third with Lentilactobacillus sp. as the most abundant species. Species belonging to the Enterobacteriaceae family were detected in higher abundance in all raw milk samples than in artisanally pasteurized milk samples. As for fungal communities, the samples were clustered into two groups, one dominated by Geotrichum candidum and the other by Pichia kudriavzevii .

Two strains, designated as Marseille-P2918 T and Marseille-P3646 T , were isolated from a 14-week-old Senegalese girl using culturomics: Urmitella timonensis strain Marseille-P2918 T (= CSUR P2918, = DSM 103634) and Marasmitruncus massiliensis strain Marseille-P3646 T (= CSUR P3646, = CCUG72353). Both strains were rod-shaped, anaerobic, spore forming motile bacteria. The 16S rRNA gene sequences of strains Marseille-P2918 T (LT598554) and Marseille-P3646 T (LT725660) shared 93.25% and 94.34% identity with Tissierella praeacuta ATCC 25539 T and Anaerotruncus colihominis CIP 107754 T , their respective phylogenetically closest species with standing in nomenclature. Therefore, strain Marseille-P2918 T is classified within the family Tissierellaceae and order Tissierellales whereas strain Marseille-P3646 T is classified within the family Oscillospiraceae and order Eubacteriales. The genome of strain Marseille-P2918 T had a size of 2.13 Mb with a GC content of 50.52% and includes six scaffolds and six contigs, and that of strain Marseille-P3646 T was 3.76 Mbp long consisting of five contigs with a 50.04% GC content. The genomes of both strains presented a high percentage of genes encoding enzymes involved in genetic information and processing, suggesting a high growth rate and adaptability. These new taxa are extensively described and characterised in this paper, using the concept of taxono-genomic description., (© 2022. The Author(s).)

Twenty-four strains of Lactococcus lactis isolated from raw goat milk collected in the Rocamadour PDO area were analysed by MLST typing and phenotypic characterisation. The strains were combined to design an indigenous starter for the production of Rocamadour PDO cheese. The strains were divided into three classes based on their technological properties: acidifying and proteolytic strains in class I (12/24 strains), slightly acidifying and non-proteolytic strains in class II (2/24 strains), and non-acidifying and non-proteolytic strains in class III (10/24 strains). Interestingly, all but three strains (21/24) produced diacetyl/acetoin despite not having citrate metabolism genes, as would classically be expected for the production of these aroma compounds. Three strains (EIP07A, EIP13D, and EIP20B) were selected for the indigenous starter based on the following inclusion/exclusion criteria: (i) no negative interactions between included strains, (ii) ability to metabolize lactose and at least one strain with the prtP gene and/or capable of producing diacetyl/acetoin, and (iii) selected strains derived from different farms to maximise genetic and phenotypic diversity. Despite consisting exclusively of L. lactis strains, the designed indigenous starter allowed reproducible cheese production with performances similar to those obtained with an industrial starter and with the sensory qualities expected of Rocamadour PDO cheese., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Methanogens, the archaea uniquely detoxifying fermentative hydrogen into methane in the digestive tract, are increasingly being detected in pathology situations, rendering their rapid identification mandatory. We improved the experimental protocol to identify broth-cultured methanogens by matrix-assisted laser desorption time-of-flight MS (MALDI-TOF-MS). A database incorporating 34 reference spectra derived from 16 methanogen reference strains representative of eight species supported further identification of 21 Methanobrevibacter smithii and 14 Methanobrevibacter oralis isolates broth-cultured from human stool and oral fluid, respectively, with scores >2. In addition, MALDI-TOF-MS differentiated five Methanobrevibacter smithii genotypes incorporated in the study. The data reported here found MALDI-TOF-MS as a first-line identification method for methanogens recovered from microbiota and clinical samples., Competing Interests: The authors declare that there are no conflicts of interest., (© 2022 The Authors.)