Distribution and functional perspective analysis of epiphytic and endophytic bacterial communities associated with marine seaweeds, Alexandria shores, Egypt.

There is an enormous diversity of life forms present in the extremely intricate marine environment. The growth and development of seaweeds in this particular environment are controlled by the bacteria that settle on their surfaces and generate a diverse range of inorganic and organic chemicals. The purpose of this work was to identify epiphytic and endophytic bacterial populations associated with ten common marine macroalgae from various areas along the Mediterranean Sea coast in Alexandria. This was done to target their distribution and possible functional aspects. Examine the effects of the algal habitat on the counting and phenotypic characterization of bacteria, which involves grouping bacteria based on characteristics such as shape, colour, mucoid nature, type of Gram stain, and their ability to generate spores. Furthermore, studying the physiological traits of the isolates under exploration provides insight into the optimum environmental circumstances for bacteria associated with the formation of algae. The majority of the bacterial isolates exhibited a wide range of enzyme activities, with cellulase, alginase, and caseinase being the most prevalent, according to the data. Nevertheless, 26% of the isolates displayed amylolytic activity, while certain isolates from Miami, Eastern Harbor, and Montaza lacked catalase activity. Geographical variations with the addition of algal extract may impact on the enumeration of the bacterial population, and this might have a relationship with host phylogeny. The most significant observation was that endophytic bacteria associated with green algae increased in all sites, while those associated with red algae increased in Abu Qir and Miami sites and decreased in Eastern Harbor. At the species level, the addition of algal extract led to a ninefold increase in the estimated number of epiphytic bacteria for Cladophora pellucida in Montaza. Notably, after adding algal extract, the number of presented endophytic bacteria associated with Codium sp. increased in Abu Qir while decreasing with the same species in Montaza. In addition to having the most different varieties of algae, Abu Qir has the most different bacterial isolates.

Copper oxide nanoparticles (CuO-NPs) as a key player in the production of oil-based paint against biofilm and other activities.

Copper oxide nanoparticles are among the metal nanoparticles gaining popularity in many biotechnological fields, particularly in marine environments. Their antimicrobial and antibiofilm activities make them appealing to many researchers. Among the various methods of producing nanoparticles, biosynthesis is crucial. Thus, a large number of reports have been made about the microbiological manufacture of these nanoparticles by bacteria. Nevertheless, bio-production by means of the cell-free supernatant of marine bacteria is still in its primary phase. This is landmark research to look at how bacteria make a lot (14 g/L) of copper oxide nanoparticles (CuO-NPs) via the cell-free supernatant of Bacillus siamensis HS, their characterization, and their environmental and medical approaches. The biosynthesized nanoparticles were characterized using a UV-visible spectrum range that provides two maximum absorption peaks, one obtained at 400 nm and the other around 550-600 nm. Diffraction of X-rays (XRD) clarifies that the size of the NPs obtained was estimated to be 18 nm using Debye-Scherrer's equation. Scanning electron microscope-energy dispersive X-ray spectroscopy (SEM-EDX) displays 91.93 % copper oxide purity. The Transmission Electron Microscope (TEM) image proves that the particles have a spherical form and an average diameter of 6.54-8.60 nm. At the environmental level, nanoparticles incorporated into oil-based paint can be used as antibiofilm tools to diminish the biofilm formed on the submerged surface in the marine environment. In disease management, NPs can be used as a wound healing agent to reduce the wound gap size as well as an anti-tumour agent to control liver cancer cells (hepatoma cells (HepG2)).

Functionalized maghemite superparamagnetic iron oxide nanoparticles (γ-Fe2O3-SPIONs)-amylase enzyme hybrid in biofuel production.

The current study describes a straightforward, biologically and environmentally friendly method for creating magnetic iron oxide (γ-Fe2O3) nanoparticles. We report here that the Bacillus subtilis SE05 strain, isolated from offshore formation water near Zaafarana, the Red Sea, Hurghada, Egypt, can produce highly magnetic iron oxide nanoparticles of the maghemite type (γ-Fe2O3). To the best of our knowledge, the ability of this bacterium to reduce Fe2O3 has yet to be demonstrated. As a result, this study reports on the fabrication of enzyme-NPs and the biological immobilization of α-amylase on a solid support. The identified strain was deposited in GenBank with accession number MT422787. The bacterial cells used for the synthesis of magnetic nanoparticles produced about 15.2 g of dry weight, which is considered a high quantity compared to the previous studies. The XRD pattern revealed the crystalline cubic spinel structure of γ-Fe2O3. TEM micrographs showed the spherically shaped IONPs had an average size of 7.68 nm. Further, the importance of protein-SPION interaction and the successful synthesis of stabilized SPIONs in the amylase enzyme hybrid system are also mentioned. The system showed the applicability of these nanomaterials in biofuel production, which demonstrated significant production (54%) compared to the free amylase enzyme (22%). Thus, it is predicted that these nanoparticles can be used in energy fields.

Large scale production of superparamagnetic iron oxide nanoparticles by the haloarchaeon Halobiforma sp. N1 and their potential in localized hyperthermia cancer therapy.

Magnetic iron oxide nanoparticles are among metal nanoparticles that attract huge attention in many biotechnological fields especially in the biomedical area. Their extensive capabilities and easy separation methodology drive them to be an interesting point to many researchers. Biosynthesis is of a major importance among different methods of nanoparticles production. Microbial synthesis of these nanoparticles by bacteria and yeasts have been reported on a wide scale. However, biosynthesis using halophilic archaea is still in an early stage. This study reveals the first contribution of the haloarchaeon Halobiforma sp. N1 to the nanobiotechnology field. It reports a rapid and economical one-step method of fabricating functionalized superparamagnetic iron oxide nanoparticles and their feasibility for hyperthermia treatment for cancer therapy. Herein, we have focused on optimizing the quantity of these fascinating nanoparticles, obtaining a very high yield of 15 g l-1 with high dispersion in water solution. Their unique characteristics enable them to participate in medical applications. They are nearly spherical in shape with a high degree of homogenity and uniformity with average diameter of 25 ± 9 nm. Also, the magnetic properties and elemental structure of the formed nanoparticles tend to be superparamagnetic like behavior with saturation magnetization of 62 emu g-1 and purity of 98.38% of iron oxide, respectively. The specific absorption rate (SAR) was measured and the particles induced significant heating power at lower frequencies which is a promising result to be applied for in vitro/in vivo hyperthermia studies in the near future.

Novel research on nanocellulose production by a marine Bacillus velezensis strain SMR: a comparative study.

Bacterial nanocellulose (BNC) is a nanofibrillar polymer that possesses unique characteristics such as high chemical purity, mechanical strength, flexibility, and absorbency. In addition, different bacterial strains can form nanocellulose (NC) in multiple shapes and sizes. This study describes the first report of a marine Bacillus strain that is able to synthesize NC. The strain identified as B. velezensis SMR based on 16S rDNA sequencing, produced highly structured NC, as confirmed by X-ray diffraction (XRD) and Scanning Electron Microscopic Analysis (SEM). In Hestrin-Schramm (HS) medium, B. velezensis SMR produced twice the quantity of BNC in comparison to the reference strain, G. xylinus ATCC 10245. The ability of B. velezensis SMR to produce NC using different industrial waste materials as growth media was tested. Growth in Ulva seaweed extract supported a 2.5-fold increase of NC production by B. velezensis SMR and a threefold increase in NC production by G. xylinus ATCC 10245. As proof of principle for the usability of NC from B. velezensis SMR, we successfully fabricated a BNC-based polyvinyl alcohol hydrogel (BNC-PVA) system, a promising material used in different fields of application such as medicine, food, and agriculture.