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The heterocyclic ether 1,4-Dioxane (1,4-DE) is a toxic by-product used widely in various industrial activities as a solvent or stabilizer. 1,4-DE was classified as a probable human carcinogen according to the United States Environmental Protection Agency (USEPA) due to its chemical and physical properties. Emerging pollutants in industrial wastewater is the major challenge for the operation of effluent treatment plant. The bioremediation of 1,4-DE is an effective approach to treat the industrial wastewater. The bacterial consortium was obtained from industrial sludge samples, Yanbu, Saudi Arabia and enriched in 1,4-DE supported basal salt saline medium. Biodegradation of 1,4-DE was studied at several concentrations ranging from 200 to 1200 mg/L. Complete mineralization of 1,4-DE from 200 to 800 mg/L was achieved in 4 to 8 days at 4% salinity. 1,4-DE utilization was studied at different salinity (4% and 6%), the results exhibited complete mineralization of 1,4-DE at 4 days and 6 days respectively. Increase in salinity to 8% displayed 92% degradation of 1,4-DE. Addition of yeast extract accelerated the biomass production correspondingly reduced the time required for biodegradation under saline condition. The bacterial consortium showed the ability to degrade 1,4-DE completely at various range of concentrations. Lab scale continuous stirred tank reactor (CSTR) was used to evaluate the industrial wastewater treatment efficacy of the bacterial consortium under saline condition. CSTR operated for 36 days displayed chemical oxygen demand (COD) removal and 1,4-DE degradation of 96% under saline condition. THF (Tetrahydrofuran) which accelerated the degradation process of 1,4-DE was completely degraded in 28 days. Bacterial analysis with high throughput sequencing technique confirmed the existence of bacterial strains like Ochrobactrum (45%), Marinobacter (21%), Stenotrophomonas (16%), Pseuodomonas (9%), Sphingomonas (4%), Bacillus (3.5%) and Sedimentibacter (1.5%). [ABSTRACT FROM AUTHOR]

Sponges forms association with many bacteria that serve as sources of new bioactive compounds. The compounds are produced in response to environmental and nutritional conditions of the environment that enable them to protect their host from colonization. In this study, three sponge bacterial endophytes were isolated, identified, and subjected to solvent extraction processes. The identified bacteria are Bacillus amyloquifaciens, Bacillus paramycoides, and Enterobacter sp. The bacteria were cultured in two different fermentation media with varying nutritional composition for the extraction process. The extracts were evaluated for antibacterial and antibiofilm activity against microfouling bacteria and the chemical composition of each extract was analyzed via gas chromatography-mass spectrometry (GC-MS). The extract from the endophytes shows varying antibacterial and antibiofilm activity against the tested strains. Several compounds were detected from the extracts including some with known antibacterial/antibiofilm activity. The results showed variations in activity and secondary metabolite production between the extracts obtained under different nutritional composition of the media. In conclusion, this study indicated the role of nutrient composition in the activity and secondary metabolites production by bacteria associated with sponge Also, this study confirmed the role of sponge bacterial endophytes as producers of bioactive compounds with potential application as antifouling (AF) agents. [ABSTRACT FROM AUTHOR]

In marine environments where biofouling occurs and has an impact on the maritime economy and environment, compounds that inhibit the attachment, growth and survival of microorganisms in a biofilm complex as well as settlement of larvae are considered potential antifouling compounds. In this study, the extracellular metabolites from two surface-associated bacteria isolated from soft coral and macroalga were evaluated for antibiofilm and antisettlement activity. The bacteria were identified using 16S rRNA gene sequencing, and the culture supernatant extract of each strain was evaluated for antibiofilm activity. The compounds present in the extracts were analysed using GC-MS. The two bacterial strains were identified as Bacillus licheniformis MBR1 and Vibrio alginolyticus MBR4 for the isolates from soft coral and macroalgae, respectively. The extracts inhibited the growth of biofilm-forming bacteria, biofilm formation and barnacle larval settlement. The GC-MS analysis of the extract detected the presence of compounds such as tetrapentacontane, octadecanoic acid, 2,3-dihydroxypropyl ester, hexadecanoic acid, 2-hydroxy-1-(hydroxymethyl) ethyl ester and 17-pentatriacontene. The results of the study show that extracellular metabolites of the bacteria associated with marine organisms could be used as natural antifouling compounds to control biofouling. [ABSTRACT FROM AUTHOR]

Probiotic bacteria are used in the development of fermented products that can increase the nutritional value of the products. Thus, the aim of this study is to examine the effect of functional ingredients on the viability of L. acidophilus in nondairy products. Four nutritional drinks were prepared including date drink (D), date-coconut drink (DC50), date-oat drink (DO50), and mixture drink (M). The drinks were fermented with 1% of L. acidophilus ATCC 314. The products were analyzed for total fat and protein, pH, titratable acidity, antioxidant activity, sensory evaluation, and viable cell count during storage time at 4 °C. At the end of the storage period, L. acidophilus was able to survive above 107 CFU/mL in all products, the maximum growth was recorded in D drink which reached 109 CFU/mL, followed by DO50 drink with 108 CFU/mL after 7 days of cold storage. The amount of lactic acid (%) increased in D, DC50, DO50, and M from (0.098, 0.027, 0.035, 0.034) to (0.159, 0.12, 0.138, 0.126) respectively. The increase in lactic acid content led to a reduction in the pH value of the products which confirmed the bacterial growth. The antioxidant activity assay indicated the addition of L. acidophilus to the products increased the antioxidant activity. The sensory evaluation showed that the consumers most preferred D and DC50 in taste and overall acceptability compared to other products DO50 and M. The present research will be used to develop a new nondairy probiotic product at low-cost with high nutritional value. [ABSTRACT FROM AUTHOR]

Clean-up of contaminated wastewater remains to be a major challenge in petroleum refinery. Here, we describe the capacity of a bacterial consortium enriched from crude oil drilling site in Al-Khobar, Saudi Arabia, to utilize polycyclic aromatic hydrocarbons (PAHs) as sole carbon source at 60°C. The consortium reduced low molecular weight (LMW; naphthalene, phenanthrene, fluorene and anthracene) and high molecular weight (HMW; pyrene, benzo(e)pyrene and benzo(k)fluoranthene) PAH loads of up to 1.5 g/L with removal efficiencies of 90% and 80% within 10 days. PAH biodegradation was verified by the presence of PAH metabolites and evolution of carbon dioxide (90 ± 3%). Biodegradation led to a reduction of the surface tension to 34 ± 1 mN/m thus suggesting biosurfactant production by the consortium. Phylogenetic analysis of the consortium revealed the presence of the thermophilic PAH degraderPseudomonas aeruginosastrain CEES1 (KU664514) andBacillus thermosaudia(KU664515) strain CEES2. The consortium was further found to treat petroleum wastewater in continuous stirred tank reactor with 96 ± 2% chemical oxygen demand removal and complete PAH degradation in 24 days. [ABSTRACT FROM AUTHOR]