Search

International audience; The environmental situation concerning pollution by (eco)toxic and persistent trace elements in Kazakhstan has been investigated by analytical reviews of scientific studies published over the past 20 years reporting concentrations of 10 toxic trace elements (TTE) observed in soil, sediments or surface water. A database of 62 articles published in Kazakh, Russian or English covered the majority of the territory of the country for soil and water samples but to a lesser extent for sediments. Reported concentrations were summarized using statistical parameters, then spatialized and finally classified in contamination classes according to local legislation. This analysis revealed some hotspots of TTE in surface waters (Cd and Pb), soil (As) and sediments (Cd and As). Hotspots of less toxic Cu, Zn and Mn were also detected. Spatialization of results allowed localization of these hotspots close to industrial sites, such as smelters or mining and metallurgic combines. Others have been shown to be close to disused mining sites or landfills with municipal waste. Methodological improvements for further studies have been suggested, such as to integrate more West Kazakhstan or remote areas in sampling campaigns, but also to describe more exhaustively the used analytical methods and to be more attentive to the speciation of the analyzed form of the element. Finally, a management strategy to strengthen a sustainable food policy has been proposed: to reduce emissions by modernization of industrial facilities and better waste management, to organize land use depending on the contamination levels and to reduce the bioavailability of the toxic elements.

The environmental situation concerning pollution by (eco)toxic and persistent trace elements in Kazakhstan has been investigated by analytical reviews of scientific studies published over the past 20 years reporting concentrations of 10 toxic trace elements (TTE) observed in soil, sediments, or surface water. A database of 62 articles published in Kazakh, Russian, or English covered the majority of the territory of the country for soil and water samples but to a lesser extent for sediments. Reported concentrations were summarized using statistical parameters, then spatialized and finally classified in contamination classes according to local legislation. This analysis revealed some hotspots of TTE in surface waters (Cd and Pb), soil (As), and sediments (Cd and As). Hotspots of less toxic Cu, Zn, and Mn were also detected. Spatialization of results allowed localization of these hotspots close to industrial sites, such as smelters or mining and metallurgic combines. Others have been shown to be close to disused mining sites or landfills with municipal waste. Methodological improvements for further studies have been suggested, such as to integrate more West Kazakhstan or remote areas in sampling campaigns, but also to describe more exhaustively the used analytical methods and to be more attentive to the speciation of the analyzed form of the element. Finally, a management strategy to strengthen a sustainable food policy has been proposed: to reduce emissions by modernization of industrial facilities and better waste management, to organize land use depending on the contamination levels, and to reduce the bioavailability of the toxic elements.

International audience; The transfer of POPs in food of animal origin has been studied by a meta-analysis of 28 peer-reviewed articles using transfer rate (TR) for milk and eggs and bioconcentration factors (BCF) for eligible tissues after establishing an adapted methodology. TRs of the most toxic PCDD/Fs into milk were generally elevated and even higher into eggs. BCFs in excreting adult animals varied widely between studies complicating to hierarchize tissues or congeners, even if liver and fat seemed to bioconcentrate more than lean tissues. Short time studies have clearly shown low BCFs contrarily to field studies showing the highest BCFs. The BCFs of PCDD/Fs in growing animals were higher in liver than in fat or muscle. In contrast to easily bioconcentrating hexachlorinated congeners, octa- and heptachlorinated congeners barely bioconcentrate. PCB transfer into milk and eggs was systematically high for very lipophilic congeners. Highly ortho-chlorinated PCBs were transferred >50% into milk and eggs and even >70% for congeners 123 and 167 into eggs. BCFs of the most toxic PCBs 126 and 169 were significantly higher than for less toxic congeners. BCFs seem generally low in PBDEs except congeners 47, 153 and 154. DDT and its metabolites showed high bioconcentration. Differences between tissues appeared but were masked by a study effect. In addition to some methodologic recommendations, this analysis showed the high transfer of POPs into eggs, milk and liver when animals were exposed justifying a strong monitoring in areas with POP exposure.

In recent years, increasing attention is paid to the ecological and global issues related to environmental pollution by heavy metals and persistent organic pollutants. Pollution by metals is very noticeable in mining areas, as well as around foundries and metallurgical plants. Persistent organic pollutants are found everywhere, which can be explained by long-distance transport by wind and water, they remain for a long period of time in the environment, have the capacity for cumulation and can pass from one species to another through the food chain. The problems associated with the presence of heavy metals and POPs in the environment is relevant for the country. In this regard, the purpose of this work was to determine the points of contamination with contaminants for further studies the effect of these compounds on the food chain. This article aimed to summarize data reporting concentrations of environmental contaminants in various regions of Kazakhstan. In the course of the work, was made an analysis of scientific articles measured concentrations of contaminants in Kazakhstan, primarily in environmental matrices (soil, water, plants) and in livestock products.Thus, territories containing elevated concentrations of heavy metals, organic pollutants and pesticides in various environmental components were identified. The obtained data have an important theoretical value and contain useful information for further research. Key words: environmental pollution,heavy metals, organic pollutants, pesticides.

International audience; The present study gives some preliminary result regarding the content of the D- and L-lactate in cow and camel milk. Twenty dromedary camel milk samples and 3 cow milk samples from Kazakhstan were analysed to determine the lactate forms in order to compare these two types of milk collected in similar conditions. The content of total lactate in camel milk was comparable to cow milk (1.82 - 2.49 g/l), but the quantity of L-Lactate was 100 times more in camel milk compared to cow milk - 2.21% of the total lactate vs 0.02% in camel and cow milk, respectively. Further analyses are necessary to understand the role of the microflora present in each specific milk.

Fermented milk is a common beverage in many countries, but its flavor is highly variable from one region to another. The fermented mare milk, common beverage in Central Asia, has a typical flavor of koumiss, but those flavors were never described using aroma compound determination. In the present study, six lactic acid bacteria were identified in local koumiss. Due to the apparent technological advantage of Lactobacillus casei and Streptococcus thermophilus (notably their acidification speed), the main objective of this study was to compare their volatile compound profiles. 35 aromatic compounds were detected. To compare the aroma profiles of each strain, the ratio proportion strain/control was calculated for each strain and for each aroma showing significantly different profiles with predominance of 2-methyl-1-propanol and 2-undecanol in milk fermented with L. casei, and of 2,3-pentanedione in milk fermented with S. thermophilus. L. casei strain produced more aroma and its profile was significantly (P>0.03) different from S. thermophilus profile.

To the Editor: Middle East respiratory syndrome coronavirus (MERS-CoV) acquired from animals causes severe pneumonia in humans, with some chains of human-to-human transmission, leading to large outbreaks. MERS-CoV is a cause of concern for global public health. The only natural host of MERS-CoV identified so far is the dromedary camel (Camel dromedarius) (1,2), and transmission from camels to humans has been documented (3). The geographic distribution of MERS-CoV in dromedaries extends beyond the Arabian Peninsula (where human cases have been reported) to North and East Africa (where human cases have not been reported) (2,4). However, MERS-CoV from a camel in Egypt and MERS-CoV from a human were phenotypically similar in tropism and replication competence in ex vivo cultures of the human respiratory tract (5). Our previous study demonstrated no evidence of MERS-CoV infection in Bactrian camels in Mongolia (6). The question whether MERS-CoV is endemic in camelids in Central Asia remains unanswered. MERS-CoV RNA was detected in swab samples from camels in Iran, which had been imported from Pakistan; however, where the infection was acquired is unclear (7). In Asia, Kazakhstan is of particular interest because large populations of 2 major camelid species overlap: 90% Bactrian (Kazakh breed including 3 ecotypes) and ≈10% dromedary (Arvana breed from Turkmenistan) and their hybrids (8). To determine whether MERS-CoV is present in camelids in Kazakhstan, we conducted a seroepidemiologic survey. During February–March 2015, blood was collected from 550 female camels (455 dromedary, 95 Bactrian) (Figure) in 2 regions, Almaty and Shymkent, which differ in camelid density (0.034 and 0.20 camels/km2, respectively; http://www.stat.gov.kz). Dromedaries were sampled in the cities/villages of Kyzylorda (105 animals from 2 herds), Zanakorgan (35 animals from 1 herd), Sholakkorgan (110 animals from 2 herds), and Akshiy (205 animals from 4 herds). Bactrian camels were sampled in Sholakkorgan (40 animals from 1 herd) and Kanshengel (55 animals from 1 herd) (Figure). For dromedary camels, mean age was 6.1 years (SD 3–7 years) and mean herd size was 53.6 animals (SD 31–70); for Bactrian camels, mean age was 6.5 years (SD 5–8 years) and mean herd size was 48.6 animals (SD 40–55). Serum samples were tested for MERS-CoV antibodies at a screening dilution of 1:20 by using a validated MERS-CoV (strain EMC) spike pseudoparticle neutralization test (9). Positive and negative controls were included in each run. Absence of positivity for any sample indicated a lack of recent or past MERS-CoV infection. Figure Density of camelids in Kazakhstan (extracted from the Ministry of National Economy of the Republic of Kazakhstan Committee on Statistics, Department of Statistics; http://www.stat.gov.kz) and specimen collection for detection of Middle East respiratory ... Two randomly selected samples each from dromedaries from Kyzlorda, Zanakorgan, and Akshiy and Bactrians from Sholakkorgan and Kanshenegel were tested for neutralizing antibody to bovine coronavirus (9). All 10 samples were seropositive, as has been reported for Bactrian camels in Mongolia and the Middle East (6,9). Given the uniformly high seroprevalence of MERS-CoV infection among dromedaries in Africa and the Arabian Peninsula, the lack of infection in dromedaries in southern Kazakhstan was surprising. Because genetically diverse MERS-CoV from Africa remains antigenically conserved with viruses from the Arabian Peninsula, the lack of antibodies is probably not explained by antigenically divergent strains (9). Feral dromedaries in Australia, which originated from animals imported from Afghanistan or Pakistan during 1840–1907, are also seronegative for MERS-CoV (10). In contrast, bovine-like coronavirus seems to be present in dromedaries everywhere (including Kazakhstan and Australia). Our study was limited by sample size and by geographic coverage. Of the ≈180,000 camels in Kazakhstan, we studied camelids from only 2 of the 13 provinces. No samples were collected from the western part of the country near Turkmenistan, where dromedaries are also common. Dromedaries are clearly a natural host of MERS-CoV. However, the finding that MERS-CoV is not endemic in dromedaries in all geographic regions suggests the possibility that dromedaries may not be the ultimate natural reservoir (i.e., the long-term host of a pathogen of an infectious disease). Topography (i.e., mountain chains) may limit camel movements from the Middle East or Africa to Central Asia, although such interchange certainly occurred centuries ago as a consequence of the silk-trade routes through southern Kazakhstan. The only known recent imports to Kazakhstan are dromedaries (Arvana breed), brought from Turkmenistan for cross-breeding with Bactrians to improve milk production (8). The findings that MERS-CoV is not universally endemic in dromedaries raises the hypothesis that certain species of bats or some other animal, the environment, or both, may constitute a maintenance community and be the true natural reservoir of MERS-CoV and that the virus spills over to camels and is maintained within camels for varying periods of time. Further studies on the epidemiology of MERS-CoV infection among camelids from central Asia are warranted.

The ever-rising global demand for energy and the issue of large volumes of unrecovered oil after primary and secondary oil production operations are driving the development and/or advancement of enhanced oil recovery (EOR) techniques. Conventional EOR processes include thermal, immiscible and miscible gas injection, chemical, and microbial enhanced oil recovery (MEOR), among others. This chapter provides an overview of MEOR including its history, strata microflora, mechanisms of MEOR for oil recovery, and a brief recount of field MEOR applications.

Consumption of fermented camel milk, named shubat, is very popular in Central Asia and especially in Kazakhstan where it is known for its medicinal and dietary properties. To identify lactic acid bacteria (LAB) camel milk and shubat were sampled from 4 regions of Kazakhstan with important camel's population. In total, 26 dairy samples from 13 selected farms representing the variability of the farming system in the country were collected. Isolated strains were identified by genotypic approach including PCR using three different pairs of primers (338f/518r; W001/23S1; Lac1/Lac2/Lac3) and 16S rDNA gene sequencing. Three genus were in majority: Lactococcus, Lactobacillus and Enterococcus. The following microorganisms were identified: Enterococcus durans ; Enterococcus faecalis; Enterococcus faecium; Lactobacillus casei; Lactobacillus casei subsp. casei; Lactobacillus curvatus; Lactobacillus kefiri; Lactobacillus paracasei; Lactobacillus sakei; Lactococcus lactis subsp. lactis; Leuconostoc mesenteroides. Identification of camel milk and shubat microflora provides a theoretical foundation for developing starter cultures by using local LAB strains for industrial production of traditional fermented milk products. (Resume d'auteur)

The effectiveness of the fermented milk product for decreasing the absorption of Lead (Pb) in vivo by testing several combinations of different strains and individual strains of LAB isolated from camel milk and shubat (fermented camel milk) was determined. During 4 weeks 0.5 ppm of Pb was given to cavies in fermented milk product and water. Control group and groups treated only by fermented milk products, also, were observed. Faeces, Blood, Heart, Lungs, Liver, Kidneys, and Spleen were analyzed. The lead concentrations in faeces of Control group and lead nitrate treated group were nearly the same. The quantity of Pb in faeces of fermented milk treated groups was higher than in Control and Water Pb groups. In the different cavies' organs of Water Pb group, the higher concentration of heavy metal (ppm) was observed in spleen (1.04), heart (0.65), kidneys (0.58), and blood (0.46) to be compared to 0.82, 0.2, 0.58 and 0.31 respectively in control group. In groups treated with fermented milk without/with Pb, the lead concentration decreased in target organs. Quantity of lead in blood samples of Control group and groups treated fermented milk products without/with Pb is nearly same. Highest concentration of blood Pb was observed for Water Pb group.

Shubat and Koumiss are traditional fermented products widely consumed in Kazakhstan and Central Asia. Microflora of those fermented products is composed of bacteria and yeasts, which could have deep impacts on beverages quality. Although, the known presence of yeast in such fermented foods, few studies on yeast microflora of Shubat and Koumiss were available. The aim of the study was to identify the main indigenous yeasts in these traditional beverages and additionally, the differences between these 2 types of fermented products. Five samples of fresh and fermented camel and mare's milk from tank were collected in 5 different farms, located in South of Kazakhstan. Farms were selected because of their importance of production of fermented milk at the regional level and the reputation of these products among the consumers. Yeast biodiversity in Shubat and Koumiss was studied using denaturing gradient gel electrophoresis (DGGE). Target DNA bands were identified according to the reference species ladder, constructed in this study. Co-migrating bands present in the DGGE profiles were resolved by species-specific PCR. Galactomyces geotrichum, Kluyveromyces marxianus, Kazachstania unispora, Saccharomyces cerevisiae, Dekkera anomala, Dekkera bruxellensis yeast were identified. Some yeasts were not identified by used primers. In all samples of Shubat and Koumiss the dominant yeast species were Kazakhstania unispora, Kluyveromyces marxianu. Other species were not present in all samples.

In Kazakhstan where Bactrian camel, dromedary camel and their hybrids are cohabiting within same farms, the consumption of camel milk is very popular because its medicinal and dietary properties. This milk is consumed under fermented form, called shubat. Shubat is still very often made on a small scale in the steppe with afermentation step driven by wild bacteria. Camel milk and shubat were sampled from 4 regions with high number of camel population. As the whole, 26 samples were obtained from 13 selected farms representing the variability of the farming system. Isolated LAB strains were identified by method of a polymorphismdetermination of 16S ribosome DNA. PCR with using two different pairs of amorces (338f/518r; W001/23S1)was done. Majority of microflora were cocci in a both milk products. The following microorganisms were identified: Enterococcus durans ; Enterococcus faecalis; Enterococcus faecium; Lactobacillus casei; Lactobacillus casei subsp. casei; Lactobacillus curvatus; Lactobacillus kefiri; Lactobacillus paracasei; Lactobacillus sakei; Lactococcus lactis subsp. lactis; Leuconostoc mesenteroides. Diversity of microorganisms in a both products was similar, but percentage of each microorganism changed during fermentation process. Yeast biodiversity in shubat was studied by using denaturing gradient gel electrophoresis (DGGE). Target DNAbands were identified according to the reference species scoring. Comigrating bands present in the DGGE profiles were resolved by species-specific PCR. The dominant yeasts in both products included Kazakhstania unispora, Saccharomyces cerevisiae and Kluyveromyces marxianus. Frequently isolated yeast species were Dekkera bruxellensis and more rarely Galactomyces geotrichum. The results of microflora identification in these products provide a theoretical foundation for developing starter cultures.