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Objective: Surgery remains the ideal treatment for hydatid cysts. However, medical treatment with albendazole can be eficient and can, in some circumstances, replace surgery.Patients and methods: We report three cases of multiple hydatid cysts considered inoperable and treated by albendazole. The evaluation of results was based on computerized tomography. Cure was defined as disappearance of the cyst and improvement was defined as a clear decrease (at least 25%) of its size or a clear increase of the cystic density.Results: Cure was obtained in 41% and improvement in 50% of 22 cysts.Comments: The efficiency of chemotherapy in hydatidosis is well proved. Medical treatment is indicated when surgery is not possible and to reduce post surgical dissemination and relapse. Indications, optimal protocols, and criteria of good response should be standardized and evaluated in large series so as to optimize medical treatment. [Copyright &y& Elsevier]

In developing countries, orphan legumes stand at the forefront in the struggle against climate change. Their high nutrient value is crucial in malnutrition and chronic diseases prevention. However, as the 'orphan' definition suggests, their seed systems are still underestimated and seed production is scanty. Seed priming is an effective, sustainable strategy to boost seed quality in orphan legumes for which up-to-date guidelines are required to guarantee reliable and reproducible results. How far are we along this path? What do we expect from seed priming? This brings to other relevant questions. What is the socio-economic relevance of orphan legumes in the Mediterranean Basin? How to potentiate a broader cultivation in specific regions? The case study of the BENEFIT-Med (Boosting technologies of orphan legumes towards resilient farming systems) project, developed by multidisciplinary research networks, envisions a roadmap for producing new knowledge and innovative technologies to improve seed productivity through priming, with the long-term objective of promoting sustainability and food security for/in the climate-sensitive regions. This review highlights the existing drawbacks that must be overcome before orphan legumes could reach the state of 'climate-ready crops'. Only by the integration of knowledge in seed biology, technology and agronomy, the barrier existing between research bench and local agricultural fields may be overcome, generating high-impact technical innovations for orphan legumes. We intend to provide a powerful message to encourage future research in line with the United Nations Agenda 2030 for Sustainable Development., Competing Interests: Author CK was employed by the company Agroland S.A. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (Copyright © 2024 Balestrazzi, Calvio, Macovei, Pagano, Laux, Moutahir, Rajjou, Tani, Chachalis, Katsis, Ghaouti, Gmouh, Majid, Elleuch, Hanin, Khemakhem, El Abed, Nunes, Araújo, Benhamrouche and Bersi.)

Plant polyphenols are nutraceutical components with relevant biological effects on human health. They act against development of several diseases including cancer. In this study, the methanolic extracts of four date palm Phoenix dactylifera leaves (Deglet Noor (DN), Barhee (B), Khalas (KS) and Khunezi (KZ)) collected from south Tunisia were preliminary analyzed for their effects against U87 (human glioblastoma) and MDA-MB-231 (human breast cancer) cell line development. Results showed that Barhee extract (30 μg/mL) was the most efficient to reduce the growth of both tumor cells to about 40% (p < 0.05) without inducing cytotoxicity. Significantly, KS, KZ, DN and B extracts (30 μg/mL) decreased MDA-MB-231 and U87 cell adhesion towards fibrinogen and fibronectin. Using integrin blocking antibodies, leaf extracts competitively decreased human glioblastoma cell attachment to immobilized antibodies by interfering to αvβ3 and α5β1 integrin receptors. At the same concentration, extracts decreased MDA-MB-23 and U87 cell migration performed with wound healing assay. Particularly, Barhee and Deglet Noor leaf extracts (30 μg/mL) significantly reduced U87 cell invasion by 52.92% (p < 0.01) and 74.56% (p < 0.01), respectively. Collegially, our findings revealed beneficial proprieties of four varieties of date palm leaf especially those displayed by DN and B extracts that may serve as active candidates against human glioblastoma and breast cancer progression., (© 2024. The Author(s), under exclusive licence to Springer Science+Business Media, LLC, part of Springer Nature.)

Many inherited conditions cause hepatocellular cholestasis in infancy, including progressive familial intrahepatic cholestasis (PFIC), a heterogeneous group of diseases with highly overlapping symptoms. In our study, six unrelated Tunisian infants with PFIC suspicion were the subject of a panel-target sequencing followed by an exhaustive bioinformatic and modeling investigations. Results revealed five disease-causative variants including known ones: (the p.Asp482Gly and p.Tyr354 * in the ABCB11 gene and the p.Arg446 * in the ABCC2 gene), a novel p.Ala98Cys variant in the ATP-binding cassette subfamily G member 5 (ABCG5) gene and a first homozygous description of the p.Gln312His in the ABCB11 gene. The p.Gln312His disrupts the interaction pattern of the bile salt export pump as well as the flexibility of the second intracellular loop domain harboring this residue. As for the p.Ala98Cys, it modulates both the interactions within the first nucleotide-binding domain of the bile transporter and its accessibility. Two additional potentially modifier variants in cholestasis-associated genes were retained based on their pathogenicity (p.Gly758Val in the ABCC2 gene) and functionality (p.Asp19His in the ABCG8 gene). Molecular findings allowed a PFIC2 diagnosis in five patients and an unexpected diagnosis of sisterolemia in one case. The absence of genotype/phenotype correlation suggests the implication of environmental and epigenetic factors as well as modifier variants involved directly or indirectly in the bile composition, which could explain the cholestasis phenotypic variability., (© 2023 University College London (UCL) and John Wiley & Sons Ltd.)

In this work, five novel phosphonium salts derived from the Michael reaction were screened for their antiplatelet activity. Our findings revealed that compounds 2a, 2b, 2c, and 2d significantly inhibit platelet aggregation triggered by ADP or collagen (P < 0.001). Notably, compound 2c inhibited the arachidonic acid pathway (P < 0.001). Moreover, the selected compounds reduce CD62-P expression and inhibit GPIIb/IIIa activation. The interactions of the active compounds with their targets, ADP and collagen receptors, P2Y12 and GPVI respectively were investigated in silico using molecular docking studies. The results revealed a strong affinity of the active compounds for P2Y12 and GPVI. Additionally, cytotoxicity assays on platelets, erythrocytes, and human embryonic kidney HEK293 cells showed that compounds 2a, 2c and 2d were non-toxic even at high concentrations. In summary, our study shows that phosphonium salts can have strong antiplatelet power and suggests that compounds 2a, 2c and 2d could be promising antiplatelet agents for the management of cardiovascular diseases., Competing Interests: Declaration of competing interest The authors would like to disclose potential competing interests in the form of a granted patent titled "Nouveaux sels de phosphonium issus des accepteurs de MICHAEL en tant qu'agents antiagrégants plaquettaire." This patent is awarded to Haitham Elleuch, Asma Haffouz, Ikram Ben Amor, Amira Jerbi, Jalel Gargouri, Farhat Rezgui, Ali Gargouri, and Basma HadjKacem. It is important to note that this patent has been issued to the ”Institut National de la Normalisation et de la Propriété Industrielle (INNORPI)” in Tunisia, bearing the reference number TN2022/0155., (Copyright © 2024 The Authors. Published by Elsevier B.V. All rights reserved.)

Soil contamination by heavy metals is one of the major problems that adversely decrease plant growth and biomass production. Inoculation with the plant growth-promoting rhizobacteria (PGPR) can attenuate the toxicity of heavy metals and enhancing the plant growth. In this study, we evaluated the potential of a novel extremotolerant strain (IS-2 T) isolated from date palm rhizosphere to improve barley seedling growth under heavy metal stress. The species-level identification was carried out using morphological and biochemical methods combined with whole genome sequencing. The bacterial strain was then used in vitro for inoculating Hordeum vulgare L. exposed to three different Cr, Zn, and Ni concentrations (0.5, 1, and 2 mM) in petri dishes and different morphological parameters were assessed. The strain was identified as Bacillus glycinifermentans species. This strain showed high tolerance to pH (6-11), salt stress (0.2-2 M), and heavy metals. Indeed, the minimum inhibitory concentrations at which bacterium was unable to grow were 4 mM for nickel, 3 mM for zinc, more than 8 mM for copper, and 40 mM for chromium, respectively. It was observed that inoculation of Hordeum vulgare L. under metal stress conditions with Bacillus glycinifermentans IS-2 T stain improved considerably the growth parameters. The capacity of the IS-2 T strain to withstand a range of abiotic stresses and improve barley seedling development under lab conditions makes it a promising candidate for use as a PGPR in zinc, nickel, copper, and chromium bioremediation., (© 2024. The Author(s) under exclusive licence to Sociedade Brasileira de Microbiologia.)

The phytochemical investigation of Thymelaea tartonraira leaves led to the isolation and characterization of six compounds, including one new flavonoid glycoside identified as hypolaetin 8-O-β-D-galactopyranoside (4) along with five known compounds, daphnoretin (1), triumbelletin (2), genkwanin (3), tiliroside (5) and yuankanin (6). Their structures were established based on spectroscopic methods, such as UV, IR, NMR, and HR-ESI-MS. Triumbelletin (2) and tiliroside (5) were isolated for the first time from T. tartonraira leaves. The antioxidant property of all isolated compounds was tested based on DPPH, FRAP and total antioxidant capacity assays. Compound 4 displayed an antioxidant potency more interesting than vitamin C with an IC 50 =15.00±0.50 μg/ml, followed by compound 5. Furthermore, the both compounds 4 and 5 were tested for their α-amylase inhibitory activity in-vitro. Compound 4 displayed higher potency to inhibit α-amylase, with an IC 50 =46.49±2.32 μg/ml, than compound 5, with an IC 50 =184.2±9.2 μg/ml, while the reference compound acarbose presented the highest potency to inhibit α-amylase with an IC 50 =0.44±0.022 μg/ml. Compound 4 displayed a strong inhibitory ability of α-glucosidase activity approximately twice more than the reference compound, acarbose, with IC 50 values of 60.00±3.00 and 125.00±6.25 μg/ml, respectively. Thus, compound 4 exhibited a specific inhibitory activity for α-glucosidase. The molecular docking studies have supported our findings and suggested that compound 4 has been involved in various binding interactions within the active site of both enzymes α-amylase and α-glucosidase., (© 2023 Wiley-VHCA AG, Zurich, Switzerland.)

A novel symmetric tetra -imidazolium- bis -heterocycle, called C7, was designed and synthesized in a quick two-step pathway, with the objective to synthesize biologically active supramolecular assembly. The synthesized compound was then analyzed for its photophysical properties, for a potential application in theragnostic (fluorescence) or phototherapy (photodynamic therapy, with the production of reactive oxygen species, such as singlet oxygen 1 O 2 ). C7 was thus screened for its biological activity, in particular against important human pathogens of viral origin (respiratory viruses such as adenovirus type 2 and human coronavirus 229E) and of fungal and bacterial origin. The compound showed limited antiviral activity, combined with very good antiproliferative activity against breast cancer, and head and neck squamous cell carcinoma models. Interestingly, the selected compound showed excellent antibacterial activity against a large array of Gram-positive and Gram-negative clinically isolated pathogenic bacteria, with a possible inhibitory mechanism on the bacterial cell wall synthesis studied with electron microscopy and molecular docking tools. Collectively, the newly synthesized compound C7 could be considered as a potential lead for the development of new antibacterial treatment, endowed with basic photophysical properties, opening the door towards the future development of phototherapy approaches.

The coronavirus pandemic (COVID-19) has created an urgent need to develop effective strategies for prevention and treatment. In this context, therapies against protease M pro , a conserved viral target, would be essential to contain the spread of the virus and reduce mortality. Using combined techniques of structure modelling, in silico docking and pharmacokinetics prediction, many compounds from algae were tested for their ability to inhibit the SARS-CoV-2 main protease and compared to the recent recognized drug Paxlovid. The screening of 27 algal molecules including 15 oligosaccharides derived from sulfated and non-sulphated polysaccharides, eight pigments and four poly unsaturated fatty acids showed high affinities to interact with the protein active site. Best candidates showing high docking scores in comparison with the reference molecule were sulfated tri-, tetra- and penta-saccharides from Porphyridium sp. exopolysaccharides (SEP). Structural and energetic analyses over 100 ns MD simulation demonstrated high SEP fragments-M pro complex stability. Pharmacokinetics predictions revealed the prospects of the identified molecules as potential drug candidates., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The COVID-19 new variants spread rapidly all over the world, and until now scientists strive to find virus-specific antivirals for its treatment. The main protease of SARS-CoV-2 (M pro ) exhibits high structural and sequence homology to main protease of SARS-CoV (93.23% sequence identity), and their sequence alignment indicated 12 mutated/variant residues. The sequence alignment of SARS-CoV-2 main protease led to identification of only one mutated/variant residue with no significant role in its enzymatic process. Therefore, M pro was considered as a high-profile drug target in anti-SARS-CoV-2 drug discovery. Apigenin analogues to COVID-19 main protease binding were evaluated. The detailed interactions between the analogues of Apigenin and SARS-CoV-2 M pro inhibitors were determined as hydrogen bonds, electronic bonds and hydrophobic interactions. The binding energies obtained from the molecular docking of M pro with Boceprevir, Apigenin, Apigenin 7-glucoside-4'-p-coumarate, Apigenin 7-glucoside-4'-trans-caffeate and Apigenin 7-O-beta-d-glucoside (Cosmosiin) were found to be -6.6, -7.2, -8.8, -8.7 and -8.0 kcal/mol, respectively. Pharmacokinetic parameters and toxicological characteristics obtained by computational techniques and Virtual ADME studies of the Apigenin analogues confirmed that the Apigenin 7-glucoside-4'-p-coumarate is the best candidate for SARS-CoV-2 M pro inhibition.

The aim of this study was to evaluate the antioxidant, the anti-inflammatory, and the antitumoral activities of the aqueous ethanolic extract from Phoenix dactylifera L. parthenocarpic dates. The antioxidant activity was carried using DPPH radical scavenging activity. The result showed that parthenocarpic dates had strongly scavenging activity on DPPH reaching 94% with an IC 50 value of 0.15 ± 0.011 mg/mL (p < 0.05). The anti-inflammatory potential was determined by the inhibitory effect of the aqueous ethanolic extract on phospholipase A 2 activity as well as on carrageenan-induced paw oedema in mice. The in vitro study showed that the extract inhibited the phospholipase A 2 activity with an IC 50 value of 130  μ g/mL and the in vivo study showed a significantly decrease in the paw oedema after 1 h compared to the control group. Finally, the antiproliferative activity of the aqueous ethanolic extract was assessed by MTT test against MCF-7 and MDA-MB-231 cancer cell lines. This extract was effective in inhibiting MDA-MB-231 and MCF-7 cancer cells growth with IC 50 values of 8 and 18 mg/mL, respectively, after 72 h treatment. These results confirm the ethnopharmacological significance of Phoenix dactylifera L. parthenocarpic dates, which could add support for its pharmaceutical use.

Three different concentrations of a purified maltogenic amylase (FSA) from fenugreek ( Trigonella foenum graecum ) seeds were incorporated into the cake formulation. The addition of FSA at 0.003, 0.005 and 0.01 U/g of cake increased the loaf volume, the number of holes (gas cells), and water absorption. Textural study revealed an improvement of the cake quality, resulting in the decrease of hardness and the increase of cohesion. Environmental scanning electron microscopy was performed on different cakes to evaluate the influence of amylase activity on microstructure. The microstructure observation showed that the FSA had a beneficial effect on starch and crumb properties. The sensory evaluation supported this result and confirmed the beneficial effect of adding FSA on cake odor and crust color. In addition, relationships between physical parameters, instrumentally textural parameters, and sensory characteristics of cake treated with FSA might be used for constructing linear regression analysis models to predict overall acceptability. In fact, overall acceptability of treated cake with FSA at 0.01 U appeared to be the most remarkable one and could be a promising technology to improve the quality of cake., Competing Interests: Compliance with ethical standardThe authors declare that they have no conflict of interest in the publication.

Background: Phoenix dactylifera L. plays an important role in social, economic and ecological Tunisian sectors. Some date palms produce parthenocarpic fruit named Sish. The objective of the present study was to extract biomolecules from parthenocarpic fruit by producing value-added products from the fruits., Results: The extraction of amylolytic activity from parthenocarpic fruit (AmyPF) was optimized using Box-Behnken design (BBD). Partial purification of about 250-fold with an activity yield of 47% was achieved. The amylase exhibited a specific activity of 80 U mg -1 protein. The optimum pH and temperature for enzyme activity were 5 and 55 °C respectively. The enzyme was highly active over a wide range of pH (5-10), and significant stabilization was observed at 60 °C. The purified enzyme belongs to the exo type of amylases. Given the economic and industrial relevance of amylases used in the food industry, three different concentrations of AmyPF (0.007, 0.014 and 0.018 U g -1 ) were incorporated into a cake formulation, resulting in a decrease in density, moisture retention and water activity and an increase in hardness., Conclusion: The beneficial effect of AmyPF on the technological characteristics of cakes was confirmed by sensory evaluation. © 2017 Society of Chemical Industry., (© 2017 Society of Chemical Industry.)

Phoenix dactylifera L. plays an important role in social, economic, and ecological Tunisian sectors. Some date palms produce parthenocarpic fruit named Sish. The aqueous ethanolic extract from P. dactylifera parthenocarpic dates demonstrated a potent inhibition of the enzymes related to type II diabetes. In this work, extraction optimization of amylase inhibitors was carried out using Box-Behnken Design. Bioactivity-guided fractionation of the 70% aqueous ethanol extract was performed to identify the active compounds. The physicochemical results by liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis showed the presence of 13 phenolic compounds. The in vitro study showed that the extract exhibited a more specific inhibitor of α-glucosidase than α-amylase with an IC 50 value of 0.6 and 2.5mg/mL, respectively. The in vivo study of this extract effect on the postprandial hyperglycemia activity showed a decrease in plasma glucose levels after 30min stronger than the Acarbose effect. These results confirmed the anti-postprandial hyperglycemia activity of the aqueous ethanolic extract from P. dactylifera parthenocarpic dates, which could lend support for its pharmaceutical use., (Copyright © 2017 Elsevier Masson SAS. All rights reserved.)

A continuous research is attempted to fulfil the highest industrial demands of natural amylases presenting special properties. New α -amylases extracted from stems and leaves of Pergularia tomentosa , which is widespread and growing spontaneously in Tunisia, were studied by the means of their activities optimization and purification. Some similarities were recorded for the two identified enzymes: (i) the highest amylase activity showed a promoted thermal stability at 50°C; (ii) the starch substrate at 1% enhanced the enzyme activity; (iii) the two α -amylases seem to be calcium-independent; (iv) Zn 2+ , Cu 2+ , and Ag 2+ were considered as important inhibitors of the enzyme activity. Following the increased gradient of elution on Mono Q-Sepharose column, an increase in the specific activity of 11.82-fold and 10.92-fold was recorded, respectively, for leaves and stems with the presence of different peaks on the purification profiles. Pergularia amylases activities were stable and compatible with the tested commercial detergents. The combination of plant amylase and detergent allowed us to enhance the wash performance with an increase of 35.24 and 42.56%, respectively, for stems and leaves amylases. Characterized amylases were reported to have a promoted potential for their implication notably in detergent industry as well as biotechnological sector.

Among various chronic disorders, cancer and diabetes mellitus are the most common disorders. This study was designed to evaluate the effectiveness of hydroalcoholic extract of Phoenix dactylifera L. leaves (HEPdL) in animal models of type II diabetes in vitro/in vivo and in a human melanoma-derived cell line (IGR-39). A liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis was also performed to determine the amount of phenolic and flavonoid compounds in this plant. The physicochemical results by LC-MS/MS analysis of HEPdL showed the presence of 10 phenolic compounds. The in vitro study showed that the extract exhibited a more specific and potent inhibitor of α-glucosidase than α-amylase with an IC 50 value of 20±1μg/mL and 30±0.8μg/mL, respectively. More importantly, the in vivo study of the postprandial hyperglycemia activity with (20mg/kg) of HEPdL showed a decrease in plasma glucose levels after 60min in resemblance to the glucor (acarbose) (50mg/kg) effect. The oral administration of HEPdL (20mg/kg) in alloxan-induced diabetic mices for 28days showed a more significant anti-diabetic activity than that of the drug (50mg/kg). Moreover, cytotoxicity effects of HEPdL in IGR-39 cancer cell lines were tested by MTT assay. This extract was effective in inhibiting cancer cells growth (IGR-39) at dose 35 and 75μg/mL. These results confirm ethnopharmacological significance of the plant and could be taken further for the development of an effective pharmaceutical drug against diabetes and cancer., (Copyright © 2016 Elsevier Masson SAS. All rights reserved.)

Oat (Avena sativa L.) seed extracts exhibited a high degree of catalytic activity including amylase activities. Proteins in the oat seed extracts were optimized for their amylolytic activities. Oat extract with amylolytic activity was separated by SDS-PAGE and a major protein band with an apparent molecular mass of 53 kDa was subjected to tryptic digestion. The generated amino acid sequences were analyzed by liquid chromatography–tandem mass spectrometry (LC/ESI/MS/MS) and database searches. These sequences were used to identify a partial cDNA from expressed sequence tags (ESTs) of A. sativa L. Based upon EST sequences, a predicted full-length gene was identified, with an open reading frame of 1464 bp encoding a protein of 488 amino acid residues (AsBAMY), with a theoretical molecular mass of 55 kDa identified as a β-amylase belonging to the plant β-amylase family. Primary structure of oat β-amylase (AsBAMY) protein indicated high similarity with other β-amylase from other cereals such as wheat (Triticum aestivum), barley (Hordeum vulgare), and rye (Secale cereale) with two conserved Glu residues (E184 and E378) assigned as the “putative” catalytic residues which would act as an acid and base pair in the catalytic process. In addition, a 3D-model of AsBAMY was built from known X-ray structures and sequence alignments. A similar core (β/α)8-barrel architecture was found in AsBAMY like the other cereal β-amylases with a specific location of the active site in a pocket-like cavity structure made at one end of this core (β/α)8-barrel domain suggesting an accessibility of the non-reducing end of the substrate and thus confirming the results of AsBAMY exo-acting hydrolase.

Statistical approaches were employed for the optimisation of the extraction of amylolytic activity from oat (Avena sativa) seeds. The application of the response surface methodology allows us to determine a set of optimal conditions (ratio seed weight/buffer volume 0.1, germination days 10 days, temperature 20 °C and pH 5.6). Experiments carried out under these conditions led to amylase production yield of 91 U/g. Its maximal activity was in the pH 5.6 and at 55 °C. Study of the incorporation of the optimised oat extract into the bread formulation revealed an improvement of the sensory quality and the textural properties of fresh and stored bread. Three-dimensional elaborations of Confocal Laser Scanning Microscopy (CLSM) images were performed on crumb of the different breads to evaluate the influence of amylase activity on microstructure. The result showed improved baking characteristics as well as overall microscopic and macroscopic appearance., (Copyright © 2014 Elsevier B.V. All rights reserved.)

Oat is a promising plant for the future. It is edible and beneficial thanks to its nutritional, medicinal and pharmaceutical uses and, hence, recognized to be useful for a healthier world. The assessment of the vital functions of oat components is important for industries requiring correct health labelling, valid during the shelf life of any product. Oil, enzymes and other biomolecules of nutraceutic or dietary usage from oats would be valorized for this purpose. Although oats have a unique and versatile composition including antioxidants and biomolecules indispensable for health, they are undervalued in comparison with other staple cereals such as wheat, barley and rice. Furthermore, oats, apart from maize, comprise a high oil content used for a wide range of beneficial purposes. In addition, they contain beta glucan that has proven to be very helpful in reducing blood cholesterol levels and other cardiovascular diseases risks. In fact, there is diversity in the composition and content of the beneficial oat components within their genotypes and the different environmental conditions and, thus, oats are amenable to be enhanced by agronomic practices and genetic approaches.

Opuntia ficus-indica f. inermis (cactus pear) flowers have wide application in folk medicine. However, there are few reports focusing on their biological activity and were no reports on their chemical composition. The nutrient composition and hexane extracts of Opuntia flowers at 4 flowering stages and their antibacterial and antifungal activities were investigated. The chemical composition showed considerable amounts of fiber, protein, and minerals. Potassium (K) was the predominant mineral followed by calcium (Ca), magnesium (Mg), sodium (Na), iron (Fe), and zinc (Zn). The main compounds in the various hexane extracts were 9.12-octadecadienoic acid (29-44%) and hexadecanoic acid (8.6-32%). The antibacterial activity tests showed that O. inermis hexane extracts have high effectiveness against Escherichia coli and Staphylococcus aureus, making this botanical source a potential contender as a food preservative or food control additive.

An amylase and lipase producing bacterium (strain C2) was enriched and isolated from soil regularly contaminated with olive washing wastewater in Sfax, Tunisia. Cell was aerobic, mesophilic, Gram-negative, motile, non-sporulating bacterium, capable of growing optimally at pH 7 and 30°C and tolerated maximally 10% (W/V) NaCl. The predominant fatty acids were found to be C(18:1)ω7c (32.8%), C(16:1)ω7c (27.3%) and C16:0 (23.1%). Phylogenetic analysis of the 16S rRNA gene revealed that this strain belonging to the genus Pseudomonas. Strain C2 was found to be closely related to Pseudomonas luteola with more than 99% of similarity. Amylase optimization extraction was carried out using Box Behnken Design (BBD). Its maximal activity was found when the pH and temperature ranged from 5.5 to 6.5 and from 33 to 37°C, respectively. Under these conditions, amylase activity was found to be about 9.48 U/ml.

The effects of copper on germination and growth of fenugreek (Trigonella foenum-graecum) was investigated separately using different concentrations of CuSO₄. The germination percentage and radical length had different responses to cupric ions: the root growth increased with increasing copper concentration up to 1 mM Cu²⁺ and was inhibited thereafter. In contrast, the germination percentage was largely unaffected by concentrations of copper below 10 mM. The reduction in root growth may have been due to inhibition of hydrolytic enzymes such as amylase. Indeed, the average total amylolytic activity decreased from the first day of treatment with [Cu²⁺] greater than 1 mM. Furthermore, copper affected various plant growth parameters. Copper accumulation was markedly higher in roots as compared to shoots. While both showed a gradual decrease in growth, this was more pronounced in roots than in leaves and in stems. Excess copper induced an increase in the rate of hydrogen peroxide (H₂O₂) production and lipid peroxidation in all plant parts, indicating oxidative stress. This redox stress affected leaf chlorophyll and carotenoid content which decreased in response to augmented Cu levels. Additionally, the activities of proteins involved in reactive oxygen species (ROS) detoxification were affected. Cu stress elevated the ascorbate peroxidase (APX) activity more than two times at 10 mM CuSO₄. In contrast, superoxide dismutase (SOD) and catalase (CAT) levels showed only minor variations, only at 1 mM Cu²⁺. Likewise, total phenol and flavonoid contents were strongly induced by low concentrations of copper, consistent with the role of these potent antioxidants in scavenging ROS such as H₂O₂, but returned to control levels or below at high [Cu²⁺]. Taken together, these results indicate a fundamental shift in the plant response to copper toxicity at low versus high concentrations., (© 2013 Elsevier Inc. All rights reserved.)

Background: Oats (Avena sativa L.) are a potential economically viable source of lipids and starch for use in foods. The aim of this study was to determine the effect of treated and untreated urban wastewater on seed germination, growth parameters and lipase and amylase activities in A. sativa., Results: Untreated wastewater was highly toxic in nature and had an inhibitory effect on seed germination and seedling growth. However, after bacterial treatment, its toxicity was significantly reduced and it showed improved seed germination. It was observed that treated wastewater had no inhibitory effect on seedling growth parameters. However, A. sativa seeds treated with untreated effluent showed reduced lipase and amylase activities., Conclusion: Treated wastewater could be used for irrigation purposes provided that it satisfies other conditions fixed by legislation., (© 2012 Society of Chemical Industry.)

We have previously cloned and characterized the thermostable phytase (PHY US417) from Bacillus subtilis US417. It differs with PhyC from B. subtilis VTTE-68013 by the R257P substitution. PHY US417 was shown to be more thermostable than PhyC. To elucidate the mechanism of how the Pro 257 changes the thermostability of Bacillus phytases, this residue was mutated to Arg and Ala. The experimental results revealed that the thermostability of the P257A mutants and especially P257R was significantly decreased. The P257R and P257A mutants recovered, respectively, 64.4 and 81.5% of the wild-type activity after incubation at 75 °C for 30 min in the presence of 5mM CaCl(2). The P257R mutation also led to a severe reduction in the specific activity and catalytic efficiency of the enzyme. Structural investigation, by molecular modeling of PHY US417 and PhyC focused on the region of the 257 residue, revealed that this residue was present in a surface loop connecting two of the six characteristic β sheets. The P257 residue is presumed to reduce the local thermal flexibility of the loop, thus generating a higher thermostability., (Copyright © 2012 Elsevier B.V. All rights reserved.)

Background: In Tunisia, prickly pear fruit grow spontaneously; it is consumed as fresh fruit, juice or jam. When the fruit is used for juice production, the seeds are discarded and go to waste. Our study aimed to extract biomolecules from seeds by producing value-added products from the fruits., Results: An amylase from Opuntia ficus-indica seeds was extracted and purified to homogeneity. An increase in specific activity of 113-fold was observed. The apparent molecular mass of the enzyme is 64 kDa. The optimum pH and temperature for enzyme activity were pH 5 and 60 °C, respectively. Under these conditions, the specific activity is 245.5 U mg(-1) . The enzyme was activated by Co(2+) and Mg(2+) (relative activity 117% and 113% respectively) at lower ion concentrations. It was strongly inhibited by Mn(2+) and Fe(2+) . Cu(2+) inhibited totally the activity of this enzyme, but Ca(2+) has an inhibitory effect which increases with ion concentration., Conclusion: The extracted enzyme belongs to the exo type of amylases and is classified as a β-cyclodextrin glycosyltransferase since it generates mainly β-cyclodextrin from starch. It exhibits high thermal stability and a broad range of pH stability, making it a promising prospect for industrial and food applications., (Copyright © 2012 Society of Chemical Industry.)

AmyTM is a truncated mutant of the α-amylase of Bacillus stearothermophilus US100. It has been derived from the wild type amylase gene via a reading frame shift, following a tandem duplication of the mutant primer, associated to an Adenine base deletion. AmyTM was composed of 720 nucleotides encoding 240 amino acid residues out of 549 of the wild type. The AmyTM protein was devoided of the three catalytic residues but still retains catalytic activity. It is Ca-independent maltotetraose producing amylase, optimally active at pH 6 and 60°C, under monomeric or multimeric forms. AmyTM is the smallest functional truncated TIM barrel. It contains the βαβα unit as the minimal subdomain associated to an enzymatic function. The enzymatic activity can, until now, be attributed to the presence of the whole domain B, in the structure of AmyTM. This mutant revealed, for the first time, the regeneration of a catalytic site after its abolition. This fact may be considered as the restoration of a primitive active site, which was lost in the course of evolution toward more stable domains., (Copyright © 2011 Elsevier Inc. All rights reserved.)

To provide insight into the potential role of a loop in domain B of several bacterial alpha-amylases, molecular and structural investigation of Bacillus stearothermophilus alpha-amylase (Amy US100) was used as a model. Combination deletion mutants of G(213), I(214) and G(215), described as a loop-forming on the surface bacterial amylases, were subjected to biochemical and structural investigation. Thermoactivity, thermostability as well calcium requirement were studied for each mutant. Thus, deletion of one residue differently affects only the thermostability. Shortening the loop by deletion of G(213)-I(214) or I(214)-G(215) improved the thermostability and reduces calcium requirement. However, the deletion of three residues has a negative effect on thermostability and reduces the optimal temperature by 17 degrees C. The structural investigation showed that stabilizing deletions contribute to reinforce the architecture of domain B and the active site conformation. The deletion of three residues reduces the flexibility of this region and abolishes a denser hydrogen bond network.

AmyUS100DeltaIG is a variant of the most thermoactive and thermostable maltohexaose forming alpha-amylase produced by Geobacillus stearothermophilus sp.US100. This enzyme which was designed to improve the thermostability of the wild-type enzyme has acquired a very high resistance to chelator agents. According to modeling structural studies and with the aim of enhancing its resistance towards chemical oxidation, a mutant (AmyUS100DeltaIG/M197A) was created by substituting methionine 197 to alanine. The catalytic proprieties of the resulting mutant show alterations in the specific activity and the profile of starch hydrolysis. Interestingly, AmyUS100DeltaIG/M197A displayed the highest resistance to oxidation compared to the AmyUS100DeltaIG and to Termamyl300, the well-known commercial amylase used in detergent. Further, performance of the engineered alpha-amylase was estimated in the presence of commonly used detergent compounds and a wide range of commercial detergent (liquid and solid). These studies indicated a high compatibility and performance of AmyUS100DeltaIG/M197A, suggesting its potential application in detergent industry.

The implications of Asn315 and Val450 in the atypical starch hydrolysis profile of Bacillus stearothermophilus Amy (a-amylase) US100 have been suggested previously [Ben Ali, Mhiri, Mezghani and Bejar (2001) Enzyme Microb. Tech. 28, 537-542]. In order to confirm this hypothesis, three mutants were generated. Of these two have a single mutation, N315D or V450G, whereas the third contains both mutations. Analysis of the starch breakdown-profile of these three mutants, as well as of the wild-type, allowed us to conclude that each single mutation induces a small variation in the hydrolysis product. However, the major end product produced by the double mutant shifts from maltopentaose/maltohexaose to maltose/maltotriose, confirming the involvement of these two residues in starch hydrolysis. The superimposition of AmyUS100 model with that of Bacillus licheniformis shows in AmyUS100 an additional loop containing residues Ile214 and Gly215. Remarkably, the deletion of these two residues increases the half-life at 100 degrees C from 15 min to approx. 70 min. Moreover, this engineered amylase requires less calcium, 25 p.p.m. instead of 100 p.p.m., to reach maximal thermostability.

Mucormycosis is a rare opportunistic infection but a fulminant disease. We report the 4 first cases of rhinocerebral mucormycosis diagnosed in Sfax region (Tunisia). They occurred in insulin dependent diabetes and developed varying clinical manifestations from facial cellulites to ocular and cerebral extension. The diagnosis of mucormycosis was not initially evoked, but confirmed tardively by anatomopathologic and mycologic examinations. The evolution was favourable in 2 cases by administration of amphotericine B associated with extensive surgical debridement and correction of the diabetes. Two patients had a fatal outcome. This infection has a severe prognosis and necessitates early diagnosis.

We report a case of Candida glabrata perinephric abscess in a patient with diabetes mellitus who recently underwent ureteropelvic surgery for lithiasic urinary tract obstruction. Surgical drainage and amphotericin B treatment led to resolution of the infection. C. glabrata urinary infection has become more prevalent over the last decade in immunocompromised patients. Drainage is indicated for development of a fungal abscess in the perinephric area. Most authors recommend administration of an antifungal adjuvant treatment.