Diverse structural, functional and valuable polysaccharides are synthesized by bacteria of all taxa and secreted into the external environment. These polysaccharides are referred to as exopolysaccharides and they may either be homopolymeric or heteropolymeric in composition and of diverse high molecular weights (10 to 1000 kDa). The material properties of exopolysaccharides have revolutionized the industrial and medical sectors due to their retinue of functional applications and prospects. These applications have been extensive in areas such as pharmacological, nutraceutical, functional food, cosmeceutical, herbicides and insecticides among others, while prospects includes uses as anticoagulant, antithrombotic, immunomodulation, anticancer and as bioflocculants. Due to the extensive applications of bacterial exopolysaccharides, this overview provides basic information on their physiologic and morphologic functions as well as their applications and prospects in the medical and industrial sectors.

Ligninolytic extracellular enzymes, including lignin peroxidase, are topical owing to their high redox potential and prospective industrial applications. The prospective applications of lignin peroxidase span through sectors such as biorefinery, textile, energy, bioremediation, cosmetology, and dermatology industries. The litany of potentials attributed to lignin peroxidase is occasioned by its versatility in the degradation of xenobiotics and compounds with both phenolic and non‐phenolic constituents. Over the years, ligninolytic enzymes have been studied however; research on lignin peroxidase seems to have been lagging when compared to other ligninolytic enzymes which are extracellular in nature including laccase and manganese peroxidase. This assertion becomes more pronounced when the application of lignin peroxidase is put into perspective. Consequently, a succinct documentation of the contemporary functionalities of lignin peroxidase and, some prospective applications of futuristic relevance has been advanced in this review. Some articulated applications include delignification of feedstock for ethanol production, textile effluent treatment and dye decolourization, coal depolymerization, treatment of hyperpigmentation, and skin‐lightening through melanin oxidation. Prospective application of lignin peroxidase in skin‐lightening functions through novel mechanisms, hence, it holds high value for the cosmetics sector where it may serve as suitable alternative to hydroquinone; a potent skin‐lightening agent whose safety has generated lots of controversy and concern.

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This study assessed the microbiological quality of various ready-to-eat foods sold in Alice, South Africa. Microbiological analysis was conducted on 252 samples which included vegetables, potatoes, rice, pies, beef and chicken stew. The isolates were identified using biochemical tests and the API 20E, API 20NE and API Listeria kits; results were analyzed using the one-way-ANOVA test. Bacterial growth was present in all the food types tested; high levels of total aerobic count were observed in vegetables, 6.8 ± 0.07 followed by rice, 6.7 ± 1.7 while pies had the lowest count (2.58 ± 0.24). Organisms isolated included: Listeria spp. (22%), Enterobacter spp. (18%), Aeromonas hydrophila (12%), Klebsiella oxytoca (8%), Proteus mirabilis (6.3%), Staphylococcus aureus (3.2%) and Pseudomonas luteola (2.4%). Interestingly, Salmonella spp. and Escherichia coli were not isolated in any of the samples. There was a statistically significant difference ( p < 0.05) in the prevalence of foodborne pathogens from hygienic and unhygienic cafeterias. The results indicated that most of the ready-to-eat food samples examined in this study did not meet bacteriological quality standards, therefore posing potential risks to consumers. This should draw the attention of the relevant authorities to ensure that hygienic standards are improved to curtain foodborne infections.

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We evaluated bioflocculant production by a freshwater actinobacteria whose 16S rDNA nucleotide sequence was deposited in GenBank as Streptomyces sp. Gansen (accession number HQ537129). Optimum culture conditions for bioflocculant production were an initial medium pH of 6.8, incubation temperature of 30 °C, agitation speed of 160 rpm and an inoculum size of 2% (v/v) of cell density 1.5 × 10 8 cfu/mL. The carbon, nitrogen and cation sources for optimum bioflocculant production were glucose (89% flocculating activity), ammonium sulfate (76% flocculating activity) and MgCl 2 . Bioflocculant pyrolysis showed three step decomposition indicative of three components while chemical analyses showed 78% carbohydrate and 22% protein (wt/wt). The mass ratio of neutral sugar, amino sugar and uronic acids was 4.6:2.4:3. FTIR spectrometry indicated the presence of carboxyl, hydroxyl and amino groups, typical for heteropolysaccharide. The bioflocculant showed a lattice structure as seen by SEM imaging. Its high flocculation activity suggests its suitability for industrial applicability.

Helicobacter pylori is a Gram-negative, micro-aerophilic, motile, curved rod that inhabits the gastric mucosa of the human stomach. It chronically infects thousands of millions of people world-wide, and is one of the most genetically diverse of bacterial species. Infection with the bacterium leads to chronic gastritis, peptic ulceration, gastric cancers and gastric mucosa-associated lymphoid-tissue (MALT) lymphoma. The prevalence of infection appears to be partly determined by geographical and socio-demographic factors, being higher in Africa than elsewhere. Current treatment, based on potent combinations that each consist of a proton-pump inhibitor and two antibiotics, is successful in 80%-90% of patients. Some undesirable side-effects, poor patient compliance and drug resistance are, however, associated with significant levels of treatment failure and with contra-indications for some patients. Antibiotic resistance in H. pylori is a growing global concern that merits the urgent attention of public-health authorities. Numerous pieces of clinical evidence have revealed that eradication of the organism from a patient results in improvement of gastritis and drastically decreases the frequency of relapse of gastric and duodenal ulcers. Natural products, including medicinal plants and honey, may offer useful alternatives in the treatment of H. pylori-related infections.

Species of actinobacteria previously isolated from Tyume River in the Eastern Cape Province of South Africa and identified by 16S rDNA sequence as Cellulomonas and Streptomyces species were evaluated as a consortium for the production of bioflocculant. Sucrose, peptone and magnesium chloride were the nutritional sources which supported optimal production of bioflocculant resulting in flocculation activities of 91%, 82% and 78% respectively. Response surface design revealed sucrose, peptone and magnesium chloride as critical media components following Plackett-Burman design, while the central composite design showed optimum concentration of the critical nutritional source as 16.0 g/L (sucrose), 1.5 g/L (peptone) and 1.6g/L (magnesium chloride) yielding optimal flocculation activity of 98.9% and bioflocculant yield of 4.45 g/L. FTIR spectrometry of the bioflocculant indicated the presence of carboxyl, hydroxyl and amino groups, typical for heteropolysaccharide, while SEM imaging revealed an interwoven clump-like structure. The molecular weight distribution of the constituents of the bioflocculants ranged 494.81-18,300.26 Da thus, an indication of heterogeneity in composition. Additionally, the chemical analyses of the purified bioflocculant revealed the presence of polysaccharides and proteins with neutral sugar, amino sugar and uronic acids in the following concentration: 5.7 mg, 9.3mg and 17.8 mg per 100mg. The high flocculation activity of the bioflocculant suggests commercial potential.