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As the most consumed source of animal protein in Southern Algeria, this study focused on monitoring the quality of fresh camel meat stored at different temperatures by analyzing some physicochemical and microbiological parameters according to national standards. Dried and salted camel meat, locally called (Kadid), was used as a control sample. The microbiological results of fresh camel meat showed a total aerobic mesophilic flora (TAMF) load of 5,8 Log10 CFU/g, 3,86 Log10 CFU/g for total coliforms, and 2,95 Log10 CFU/g for fecal coliforms. All samples analyzed were free of pathogenic bacteria, namely coagulase-positive staphylococci (CoPS), Listeria monocytogenes, and Salmonella spp. However, coagulase-negative staphylococci (CoNS) species with a load of 3,47 Log10 CFU/g were identified as follows: S. saprophyticus and S. epidermidis. In less than 7 days, sample B stored at room temperature experienced deterioration, with the microbial load exceeding the maximum acceptable threshold (M) set by national regulations, along with changes in physicochemical parameters, rendering the product unfit for consumption. This degradation was faster compared to the sample A stored at a maximum temperature of +10°C. However, for the control sample, the physicochemical results of dried and salted camel meat (Kadid) showed an acidic medium (pH=5,26). The analyzed samples had moisture content (MC %), sodium chloride content (SCC %), and total solid content (TSC %) of 10,73%, 0,3% (3g/L), and 89,27%, respectively. From a microbiological points of view, fresh camel meat stored at +10°C meets national legislation requirements for a maximum storage of one month. In contrast, the physicochemical and microbiological characteristics of dried and salted camel meat (Kadid) allow it to be preserved for an extended period, even at room temperature. The traditional method of preparing and preserving the meat has proven effective against microbial contaminants. It maintains a balance of physicochemical parameters that enhance preservation and improve the nutritional and organoleptic quality compared to chilled fresh camel meat.

This study aims to estimate the in situ effect of Phoenician juniper leaves on the physicochemical and microbiological quality of fermented goat’s milk stored under ambient conditions. In this study, we used two samples. The first sample was goat's milk flavored with juniper leaves, compared to the control sample without juniper leaves. We analyzed three physicochemical parameters: pH, titratable acidity, and temperature. Furthermore, the bacteriological analysis focused on the following parameters: Total aerobic mesophilic flora (TAMF), total coliforms (TC), fecal coliforms (FC), coagulase-positive Staphylococci (CoPS), and pathogenic bacteria (Salmonella spp and Listeria monocytogenes). The physicochemical results showed a change in the pH and titratable acidity of both samples with a higher acidity for the test sample compared to the control sample. This change was marked by an increase in a load of total aerobic mesophilic flora and lactic acid bacteria, a decrease in the total coliforms and thermotolerant coliforms, and the Staphylococci load in the test sample compared to the control sample, which experienced an increase in these bacterial parameters. For the test sample, juniper leaves reduced bacterial contaminants in fermented goat’s milk by 38% for total coliforms, 41% for fecal coliforms, and 89% for staphylococci. Both samples were free of Salmonella spp and L. monocytogenes. These results are probably due to the effect of bioactive compounds of Juniperus phoenicea L leaves known for their antimicrobial effect. This traditional practice of our ancestors can improve the quality of fermented goat’s milk stored even at ambient temperature.

Abstract Redox‐active materials that exhibit both electrochromism and electrofluorochromism have great potential as multifunctional elements in optoelectronics. Here, in situ spectroelectrochemistry is presented on NU‐1000, a zirconium pyrenetetrabenzoate metal–organic framework. A thin film of NU‐1000 exhibits reversible color changes between light yellow and dark blue when subjected to an alternating electrochemical potential. In situ fluorescence excitation‐emission spectral mapping elucidates a dominant blue emission of highly fluorescent electrochromic NU‐1000 that is being quenched via an oxidation reaction. Density‐functional theory calculations reveal the forbidden optical transition between the singly occupied molecular orbital (SOMO) and the lowest unoccupied molecular orbital (LUMO) in the oxidized linker as the cause of the quenching. Double potential step chronoamperometry measures response times as fast as a dozen seconds and excellent switching stability over 500 cycles without noticeable attenuation of the color contrast. These findings provide valuable insight into the electrochromism and electrofluorochromism in metal–organic frameworks, offering exciting opportunities for developing advanced multifunctional porous materials with potential applications in optoelectronics and sensing.

Date palms (Phoenix dactylifera L.) are of ecological, socio-economic, and nutritional importance for the Saharan population. This study aims to scan the production of dates, particularly in Bechar (Southwest of Algeria) by determining the main varieties of dates, and the areas of agricultural exploitation intended for their production in Bechar. Several palm oases were visited to survey the different varieties of dates produced in Bechar, while the statistical data relating to the dates production and the date-producing agricultural areas were obtained through bibliographic, documentary research, as well as data from the agricultural services department of Bechar (DSA). The obtained results showed that Algeria is among the leading producers of dates, ranking fourth worldwide through 16 date-producing provinces, where the province of Bechar occupies the 6th position with production going from 2,446 t (2015) to 59,781.3 t (2021). A rate of 85% of this production is attributed to the soft date variety 'Ghers' and its analogs, while 15% is for the dry dates 'Degla Beida' and similar ones. The survey carried out in Bechar showed richness and diversity in terms of the variety of dates. Among the 10 component municipalities of Bechar province, Taghit is the most dates-producing municipality, constituting a rate of 12,72% of the total production. The agricultural area intended for the production of dates has also undergone an evolution where it reached a total of 13,918.5 ha (Agricultural area occupied by date palms) of which 10,027 ha is the date-producing agricultural area. The challenges facing this crop mainly lie in phytopathogenic diseases affecting the date palms and in climatic factors, namely drought and water stress. The local and national authorities should intervene to maintain and even promote the place of date-producing provinces in Algeria, which constitutes one of the drivers of economic development outside the oil sector.

Abstract Barium phosphate (Ba3(PO4)2) is a class of material that has attracted significant attention thanks to its chemical stability and versatility. However, the use of Ba3(PO4)2 as a photocatalyst is scarcely reported, and its use as a photocatalyst has yet to be reported. Herein, Ba3(PO4)2 nanoflakes synthesis is optimized using sol‐gel and hydrothermal methods. The as‐prepared Ba3(PO4)2 powders are investigated using physicochemical characterizations, including XRD, SEM, EDX, FTIR, DRS, J–t, LSV, Mott‐Schottky, and EIS. In addition, DFT calculations are performed to investigate the band structure. The oxidation capability of the photocatalysts is investigated depending on the synthesis method using rhodamine B (RhB) as a pollutant model. Both Ba3(PO4)2 samples prepared by the sol‐gel and hydrothermal methods display high RhB photodegradation of 79% and 68%, respectively. The Ba3(PO4)2 obtained using the sol‐gel process exhibits much higher stability under light excitation after four regeneration cycles. The photocatalytic oxidation mechanism is proposed based on the active species trapping experiments where O2•‒ is the most reactive species. The finding shows the promising potential of Ba3(PO4)2 photocatalysts and opens the door for further investigation and application in various photocatalytic applications.

The orthophosphate BaNi2Fe(PO4)3 has been synthesized by a solid-state reaction route and characterized by single-crystal X-ray diffraction and energy-dispersive X-ray spectroscopy. The crystal structure comprises (100) sheets made up of [Ni2O10] dimers that are linked to two PO4 tetrahedra via common edges and vertices and of linear infinite [010] chains of corner-sharing [FeO6] octahedra and [PO4] tetrahedra. The linkage of the sheets and chains into a framework is accomplished through common vertices of PO4 tetrahedra and [FeO6] octahedra. The framework is perforated by channels in which positionally disordered Ba2+ cations are located.

Abstract This present work is a part of the liquid discharges treatment topic by studying the removal performance for thermotolerant coliforms (FC) and fecal streptococci (F.Strep) by a local natural light green clay from Kenadsa (Bechar-Algeria) under continuous adsorption processes in a fixed-bed column. The study estimated the clay adsorbing efficiency by the adsorption technique for bacteria contaminating the dairy effluent by determining the bacterial load before and after treatment. The mean log counts per 100 ml for FC and F.Strep were assessed by MPN method on liquid medium. The clay material characterizations were made through X-ray diffraction, X fluorescence spectrometry and Fourier transform infrared spectroscopy analysis. Besides, some parameters were estimated such as the breakthrough time tb (clay filter breakdown); the amount of the contaminating bacteria that was removed at the breakthrough time Xb and the exhaustion of disinfection capacity Xe; the total amount of contaminating bacteria flowing through the column Xtotal; and the total removal efficiency (Y). According to the XRD, XRF and FTIR results, the predominant mineral constituents were silicon dioxide, aluminum oxide, ferric oxide and magnesium oxide with rates of 59,44; 18,09; 7,79; and 3,87%, respectively, and hence, their classification among non-swelling clay minerals, illite is the major mineral group of this material. The results of the bacteriological analysis of raw dairy effluents showed an average bacterial load of 3,88 Log10 and 4,1 Log10 CFU/100 mL for FC and F.Strep, respectively, exceeding the thresholds set by the national and the international regulations. The results of the dairy effluents treated by the tested material have shown that the used clay has a relatively high adsorption property for the clay fixed-bed system (3 cm of bed height), expressed by a total removed efficiency Y (%) of FC and F.Strep used to evaluate the column performance ranging from 55 to 84%. It gives a higher log removal for FC and F.Strep (0.98–1.65 Log10) reported from the first adsorption process, and a breakthrough time ranged from 100 to 250 min, which was inversely proportional to the initial bacterial load of discharges and also linked to the nature of the bacterial contaminants. When the breakthrough occurs earlier, the column service life will be shortened. For the studied parameters, the results of treated effluent complied with national and WHO regulations for unrestricted agricultural irrigation, otherwise, as authorized effluents to be discharged into nature without risks. These preliminary results are very promising at laboratory scale as an innovative green technology, treatment method respecting the environment and opens up prospects for the future, where the modification or the optimization of operating conditions such as the bed height of the fixed bed for adsorption, the volumetric flow rate or the clay structure like the particle size distribution of the adsorbents, known as one of the adsorbent classes endowed with an antimicrobial property, can improve the column performance, and further, the removal or even more the disinfection process by adsorption method.

Abstract Milk and dairy products’ production lines generate pollution in the form of food waste. The management of this waste concerns professionals that fit the purpose of this study to assess the chemical risk of the raw liquid effluents that are discharged from a milk processing plant located in Bechar (Southwest of Algeria) by analyzing the main chemical indicator parameters of water pollution following official analytical methods. A total of ten samples were analyzed during the months of February, March and April of the year 2019. The obtained results were interpreted according to the regulatory requirements recommended by the Algerian standard related to threshold limit of physicochemical parameters’ values. The obtained results showed pollution signs revealed by high levels of the organic matters, expressed by significant means related to the following parameters: chemical oxygen demand (COD: 810.33 mg/L), 5 days-biochemical oxygen demand (BOD5: 797.91 mg/L), total suspended solids (TSS: 47.3 mg/L) and turbidity (174.014 NTU) exceeding those required by the national standard, except other physicochemical parameters, such as pH, conductivity, sulfate, nitrate and nitrite contents that did not exceed the threshold of acceptable values. Although these raw effluents present a high organic load expressed by average BOD5/COD ratio equal to 0.985, they constitute organic matters in a dissolved form (average value of the TSS/BOD5 ratio = 0.076). Furthermore, The COD/BOD5 ratio that had an average value equal to 1.015 underlines the biodegradability character of discharged dairy effluents. The high pollution levels which are aggravated by the lack of wastewater treatment can hurt the environment and the biological diversity and, therefore the humans' health. This requires an immediate intervention for a solution, where it is very important that proper wastewater treatment systems should be installed for the environment protection and for the ecological balance. Otherwise, it may constitute a risk to the public health on medium- to long-term by affecting the quality of the underground reservoir known as the main source of supply for the inhabitants of arid and semi-arid areas.

Single crystals of sodium copper(II) indium bis[phosphate(V)], NaCuIn(PO4)2, were grown from the melt under atmospheric conditions. The title phosphate crystallizes in the space group P21/n and is isotypic with KCuFe(PO4)2. In the crystal, two [CuO5] trigonal bipyramids share an edge to form a dimer [Cu2O8] that is connected to two PO4 tetrahedra. The obtained [Cu2P2O12] units are interconnected through vertices to form sheets that are sandwiched between undulating layers resulting from the junction of PO4 tetrahedra and [InO6] octahedra. The two types of layers are alternately stacked along [101] and are joined into a three-dimensional framework through vertex- and edge-sharing, leaving channels parallel to the stacking direction. The channels host the sodium cations that are surrounded by four oxygen atoms in form of a distorted disphenoid.

Crystals of the new compound, AgSr4Cu4.5(PO4)6, were grown successfully by the hydrothermal process. The asymmetric unit of the crystal structure of the title compound contains 40 independent atoms (4 Sr, 4.5 Cu, 1 Ag, 6 P and 24 O), which are all in general positions except for one Cu atom, which is located on an inversion centre. The Cu atoms are arranged in CuOn (n = 4 or 5) polyhedra, linked through common oxygen corners to build a rigid three-dimensional motif. The connection of these copper units is assured by PO4 tetrahedra. This arrangement allows the construction of layers extending parallel to the (100) plane and hosts suitable cavities in which Ag+ and Sr2+ cations are located. The crystal-structure cohesion is ensured by ionic bonds between the silver and strontium cations and the oxygen anions belonging to two adjacent sheets. Charge-distribution analysis and bond-valence-sum calculations were used to validate the structural model.

The title compound, sodium (sodium,manganese) triiron(II,III) tris[vanadate(V)], (Na0.70)(Na0.70,Mn0.30)(Fe3+,Fe2+)2Fe2+(VO4)3, was prepared by solid-state reactions. It crystallizes in an alluaudite-like structure, characterized by a partial cationic disorder. In the structure, four of the 12 sites in the asymmetric unit are located on special positions, three on a twofold rotation axis (Wyckoff position 4e) and one on an inversion centre (4b). Two sites on the twofold rotation axis are entirely filled by Fe2+ and V5+, whereas the third site has a partial occupancy of 70% by Na+. The site on the inversion centre is occupied by Na+ and Mn2+ cations in a 0.7:0.3 ratio. The remaining Fe2+ and Fe3+ atoms are statistically distributed on a general position. The three-dimensional framework of this structure is made up of kinked chains of edge-sharing [FeO6] octahedra stacked parallel to [10-1]. These chains are held together by VO4 tetrahedral groups, forming polyhedral sheets perpendicular to [010]. Within this framework, two types of channels extending along [001] are present. One is occupied by (Na+/Mn2+) while the second is partially occupied by Na+. The mixed site containing (Na+/Mn2+) has an octahedral coordination sphere, while the Na+ cations in the second channel are coordinated by eight O atoms.