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The presence of toxic substances in water leads to varied adverse impacts on living organisms through direct or indirect exposure. Bisphenol A (BPA) is a toxic chemical that has been periodically discharged into wastewater treatment plants. BPA is an industrial precursor used for the manufacture of polycarbonates and epoxy resins. This compound has been discharged in the environment (water, soil, and air) by various means during the manufacturing processes (in particular during heating, handling, and transport of products). Several treatment methods, such as physical, chemical, and biological processes have been traditionally used to ensure higher removal of BPA from wastewater, albeit with lower removal rates or with resulting secondary pollution. In this context, this minireview is an attempt to explore different aspects of research in the field of biological removal of BPA from wastewater. The biological treatment is generally more effective than the physico-chemical treatment, as the former causes lower amounts of secondary pollution. Of the various biological modes of treatment, enzymatic degradation is the most effective, as it does not require the addition of nutrients for the microbial growth. Thus, it prevents the accumulation of biomass in water. Moreover, this technique is effective even while using small quantities of enzymes and it does not require a process control of the treatment conditions. Although the utility of the enzymatic treatment is approved more and more, the process remains highly expensive because of the higher cost of the raw material and the lower stability of enzymes. In this context, there is a need to find a solution for the economical production of enzymes to ensure the complete removal of BPA from wastewater in an eco-friendly manner. Key words: bisphenol A, biological treatment, enzymes, removal, wastewater. La presence des substances toxiques dans l'eau peut avoir des effets nefastes sur les organismes vivants a la suite d'une exposition directe ou indirecte des organismes a ces substances. Le bisphenol A (BPA) est un parmi les produits chimiques qui sont periodiquement decharges dans les eaux usees. Ce produit est un precurseur industriel primaire dans la fabrication de polycarbonates et de resines epoxy. Ce compose est decharge dans l'environnement (eau, sol et air) par differentes voies lors des processus de fabrication (en particulier pendant le chauffage, la manipulation et le transport des produits). Plusieurs types de traitement (physique, chimique et biologique) sont employes afin de degrader le BPA present dans les eaux usees. Cette revue met l'accent particulierement sur sa degradation par des procedes biologiques. Ces methodes sont plus efficaces que les procedeis physicochimiques. En effet, le traitement biologique offre une solution efficace et fiable pour l'elimination du BPA present dans les eaux usees sans pollution secondaire. La degradation enzymatique est le procede le plus efficace et le plus utilise et il ne demande pas l'ajout de nutriments pour la croissance microbienne. De plus, il permet d'eviter une accumulation de biomasse. En outre, cette technique est efficace meeme en utilisant de faibles quantites d'enzymes et ne necessite pas un processus de controle des conditions de traitement. Bien que l'utilitee du traitement enzymatique soit de plus en plus approuvee, le procede reste trees coflteux compte tenu du prix eleve de la matiere premiere et de la faible stabilitee des enzymes. Dans ce contexte, la recherche d'une solution permettant la production des enzymes a un coute economique s'avere indispensable afin d'assurer l'eelimination complete du BPA des eaux usees. Mots-cles: bisphenol A, traitement enzymatique, traitement microbien, eaux usees, enzymes., Introduction Les eaux usees et les boues d'epuration contiennent une grande variete de composes dissous mineraux et organiques. La majeure partie de ces polluants est eliminee par precipitation, coagulation-floculation, adsorption [...]

Spices are parts of plants that due to their properties are used as colorants, preservatives, or medicine. The uses of spices have been known since long time, and the interest in the potential of spices is remarkable due to the chemical compounds contained in spices, such as phenylpropanoids, terpenes, flavonoids, and anthocyanins. Spices, such as cumin (cuminaldehyde), clove (eugenol), and cinnamon (cinnamaldehyde) among others, are known and studied for their antimicrobial and antioxidant properties due to their main chemical compounds. These spices have the potential to be used as preservatives in many foods namely in processed meat to replace chemical preservatives. Main chemical compounds in spices also confer other properties providing a variety of applications to spices, such as insecticidal, medicines, colorants, and natural flavoring. Spices provide beneficial effects, such as antioxidant activity levels that are comparable to regular chemical antioxidants used so they can be used as a natural alternative to synthetic preservatives. In this review, the main characteristics of spices will be described as well as their chemical properties, different applications of these spices, and the advantages and disadvantages of their use. [ABSTRACT FROM AUTHOR]

Several food additives are added in food for their preservation to maintain the freshness of food (antioxidants) or to slow down or stop the growth of microorganisms (preservative agents). Nitrites and nitrates are used as preservative agents in meat. Nitrites give a smoked taste, a pinkish color in the meat and protect the consumers against the risk of bacterial deterioration. Their addition is however very limited as, in high dose, it can have risks on human health and the environment. Nitrites may also combine with secondary or tertiary amines to form N-nitroso derivatives. Certain N-nitroso compounds have been shown to produce cancers in a wide range of laboratory animals. Thus, alternatives of nitrates and nitrites are the object of numerous research studies. Alternatives, such as the addition of vitamins, fruits, chemicals products, natural products containing nitrite or spices, which have similar properties of nitrites, are in evaluation. In fact, spices are considered to have several organoleptic and anti-microbial properties which would be interesting to study. Several spices and combinations of spices are being progressively evaluated. This review discusses the sources of nitrites and nitrates, their use as additives in food products, their physicochemical properties, their negatives effects and the use of alternatives of nitrites and nitrates in preserving meat products. [ABSTRACT FROM AUTHOR]

Pseudomonas luteola (P. luteola) is rarely reported as a human bacterial pathogen. However, it may cause several serious infections, mainly in immuncompromised patients. We report here the first case of urinary tract infection due to P. luteola and we review, by searching in Pub Med all cases of P. luteola infection. [ABSTRACT FROM AUTHOR]