scholarly journals Microbial Populations of Fresh and Cold Stored Donkey Milk by High-Throughput Sequencing Provide Indication for A Correct Management of This High-Value Product

2020 ◽  
Vol 10 (7) ◽  
pp. 2314 ◽  
Author(s):  
Pasquale Russo ◽  
Daniela Fiocco ◽  
Marzia Albenzio ◽  
Giuseppe Spano ◽  
Vittorio Capozzi

Donkey milk is receiving increasing interest due to its attractive nutrient and functional properties (but also cosmetic), which make it a suitable food for sensitive consumers, such as infants with allergies, the immunocompromised, and elderly people. Our study aims to provide further information on the microbial variability of donkey milk under cold storage conditions. Therefore, we analysed by high-throughput sequencing the bacterial communities in unpasteurized donkey milk just milked, and after three days of conservation at 4 °C, respectively. Results showed that fresh donkey milk was characterized by a high incidence of spoilage Gram-negative bacteria mainly belonging to Pseudomonas spp. A composition lower than 5% of lactic acid bacteria was found in fresh milk samples, with Lactococcus spp. being the most abundant. The occurrence of microbial species belonging to risk group 2 was found in fresh milk. After three days of cold storage, the bacterial biodiversity of donkey milk was strongly reduced, since about 93% of the bacterial communities were identified as different species of psychrotrophic Pseudomonas. In conclusion, we report a preliminary description of the microbial diversity of donkey milk by using a metagenomic approach and encouraging a correct exploitation of this high-value niche product.

Fermentation ◽  
2020 ◽  
Vol 6 (4) ◽  
pp. 100
Author(s):  
Eleni Kamilari ◽  
Dimitrios A. Anagnostopoulos ◽  
Photis Papademas ◽  
Marina Efthymiou ◽  
Svitlana Tretiak ◽  
...  

In general, it is a common practice among dairy producers to store the milk in the refrigerator directly after milking, in order to preserve it and prevent the development of spoilage microbes. However, the impact of keeping the milk in the refrigerator overnight on milk microbial diversity has been poorly investigated. This study aimed to provide a snapshot of the bacterial composition of goat milk after direct storage at −80 °C and after being kept overnight at 4 °C and then in storage at −80 °, using high-throughput sequencing (HTS). Goat milk samples from four different farms were analyzed, to reveal that milk bacterial diversity differed between the two different storage conditions. Goat milk directly stored at −80 °C was characterized by the presence of the Gram-negative contaminants Pseudomonas and Acinetobacter, in addition to the genera Corynebacterium, Chryseobacterium, Bacteroides and Clostridium. Milk samples that were kept overnight at 4 °C were characterized by a reduction in their bacterial biodiversity and the predominance of the Gram-negative, aerobic Phyllobacterium. Overall, HTS methodologies provide an in-depth identification and characterization of the goat raw milk microbiome. Further, they offer a better understanding of the contribution of cold storage conditions to milk microbiota formation. This study may assist dairy producers in improving raw milk and raw milk cheeses quality and guaranteeing consumers’ safety.


2017 ◽  
Vol 251 ◽  
pp. 67-72 ◽  
Author(s):  
Maria de los Dolores Soto del Rio ◽  
Alessandra Dalmasso ◽  
Tiziana Civera ◽  
Maria Teresa Bottero

Author(s):  
Rose Chinly Mae H. Ortega ◽  
Sharon Rose M. Tabugo ◽  
Joey Genevieve T. Martinez ◽  
Chinee S. Padasas ◽  
Marilen P. Balolong ◽  
...  

2014 ◽  
Vol 86 (1) ◽  
pp. 485-494 ◽  
Author(s):  
CRISTIANO ANDRÉ STEFFENS ◽  
CASSANDRO V.T. DO AMARANTE ◽  
ERLANI O. ALVES ◽  
AURI BRACKMANN

The objective of this study was to evaluate the effect of controlled atmosphere (CA) on quality preservation of ‘Laetitia’ plums, mainly on internal breakdown, in order to determine the best CA storage conditions. Two experiments were carried out one in 2010, and another in 2011. In 2010, besides cold storage (CS; 21.0 kPa O2 + 0.03 kPa CO2), the fruits were stored under the following CA conditions (kPa O2+kPa CO2): 1+3, 1+5, 2+5, 2+10, and 11+10. In 2011, the fruits were stored under CS and CA of 1+0, 1+1, 2+1, and 2+2. The fruit stored under different CA conditions had lower respiration and ethylene production, better preservation of flesh firmness, texture and titratable acidity, lower skin red color, and lower incidence of skin cracking than the fruit in CS. In 2010, the fruit under CA with 2+5, 1+5, and 1+3 had a pronounced delay in ripening, although it exhibited a high incidence of internal breakdown. In 2011, the CA conditions with 2+1 and 2+2 provided the best delay in ripening and a reduced incidence of internal breakdown. The best CA condition for cold storage (at 0.5°C) of ‘Laetitia’ plums is 2 kPa O2 + 2 kPa CO2.


2018 ◽  
Vol 84 (9) ◽  
Author(s):  
Bing Li ◽  
Wei-Min Wu ◽  
David B. Watson ◽  
Erick Cardenas ◽  
Yuanqing Chao ◽  
...  

ABSTRACTA site in Oak Ridge, TN, USA, has sediments that contain >3% iron oxides and is contaminated with uranium (U). The U(VI) was bioreduced to U(IV) and immobilizedin situthrough intermittent injections of ethanol. It then was allowed to reoxidize via the invasion of low-pH (3.6 to 4.0), high-nitrate (up to 200 mM) groundwater back into the reduced zone for 1,383 days. To examine the biogeochemical response, high-throughput sequencing and network analysis were applied to characterize bacterial population shifts, as well as cooccurrence and coexclusion patterns among microbial communities. A pairedttest indicated no significant changes of α-diversity for the bioactive wells. However, both nonmetric multidimensional scaling and analysis of similarity confirmed a significant distinction in the overall composition of the bacterial communities between the bioreduced and the reoxidized sediments. The top 20 major genera accounted for >70% of the cumulative contribution to the dissimilarity in the bacterial communities before and after the groundwater invasion.Castellaniellahad the largest dissimilarity contribution (17.7%). For the bioactive wells, the abundance of the U(VI)-reducing generaGeothrix,Desulfovibrio,Ferribacterium, andGeobacterdecreased significantly, whereas the denitrifyingAcidovoraxabundance increased significantly after groundwater invasion. Additionally, seven genera, i.e.,Castellaniella,Ignavibacterium,Simplicispira,Rhizomicrobium,AcidobacteriaGp1,AcidobacteriaGp14, andAcidobacteriaGp23, were significant indicators of bioactive wells in the reoxidation stage. Canonical correspondence analysis indicated that nitrate, manganese, and pH affected mostly the U(VI)-reducing genera and indicator genera. Cooccurrence patterns among microbial taxa suggested the presence of taxa sharing similar ecological niches or mutualism/commensalism/synergism interactions.IMPORTANCEHigh-throughput sequencing technology in combination with a network analysis approach were used to investigate the stabilization of uranium and the corresponding dynamics of bacterial communities under field conditions with regard to the heterogeneity and complexity of the subsurface over the long term. The study also examined diversity and microbial community composition shift, the common genera, and indicator genera before and after long-term contaminated-groundwater invasion and the relationship between the target functional community structure and environmental factors. Additionally, deciphering cooccurrence and coexclusion patterns among microbial taxa and environmental parameters could help predict potential biotic interactions (cooperation/competition), shared physiologies, or habitat affinities, thus, improving our understanding of ecological niches occupied by certain specific species. These findings offer new insights into compositions of and associations among bacterial communities and serve as a foundation for future bioreduction implementation and monitoring efforts applied to uranium-contaminated sites.


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