Recent Patents on Biotechnology - Volume 7, Issue 3, 2013

Bacteriocins produced by lactic acid bacteria are of keen interest to the food industry for their bio-preservative potential and antimicrobial properties. The increasing demand for high quality ‘safe’ foods which are not extensively processed has created a niche for natural food preservatives. The bacteriocins (produced by bacteria) derived their name after the genera that produce them, hence bacteriocins produced by genus Pediococcus are known as Pediocin. Pediocins are antimicrobial peptides which show a strong activity against food spoilage and pathogenic bacteria, also are thermostable in nature as well as stable over a wide range of pH. Pediocin produced by Pediococcus acidilactici, has been generally recognized as safe (GRAS). The current review summarizes about the progress made on the Pediocin research from patent perspective along with the immense potential of these Pediococcus derived bacteriocins not only as antimicrobial, biopreservative and probiotic agents but also for the treatment of cancer, body odors and other health promoting actions. The relevant patents have been listed and briefly analyzed to upgrade and benefit food industries by prolonging the shelf life of various products.

Flavonoids are substances which are widely distributed in the plant kingdom. They occur in considerable quantities in common food products, spices and beverages. Interest of researchers has been greatly enhanced towards therapeutic potential of flavonoids in last some years. This review summarizes important patents pertaining to recent biotechnological techniques applied for the production, analysis of biosynthetic pathways, effects and applications of different flavonoids. For systematic studies investigations which have been published in the form of patents, are classified in different sectors like biosynthesis, medical application, antimicrobial activity, alteration of flower color, industrial application, cosmetics, food and plant tissue culture. A number of activities have been observed in each sector with vast area of research on flavonoids.

Hydroxynitrile lyases (HNLs) catalyze the cleavage as well as the formation of cyanohydrins. The latter reaction is valuable for the stereoselective C-C bond formation by condensation of HCN with carbonyl compounds. The resulting cyanohydrins serve as versatile building blocks for a broad range of chemical and enzymatic follow-up reactions. A significant number of (R)- and (S)-selective HNLs are known today and the number is still increasing. HNLs not only exhibit varying substrate scope but also differ in sequence and structure. Tailor-made enzymes for large-scale manufacturing of cyanohydrins with improved yield and enantiomeric excess are very interesting targets, which is reflected in a solid number of patents. This review will complement and extend our recent review with a strong focus on applications of HNLs for the synthesis of highly functionalized, chiral compounds with newest literature, recent and current patent literature.

Hemicelluloses comprise a major part of renewable plant biomass and therefore have received considerable attention in lignocellulose biotechnology. Hemicelluloses are a heterogeneous group of structural polysaccharides such as xylan, mannan and arabinan named after their major constituent monomeric sugar. Bioconversion of hemicelluloses proceeds through hydrolysis using hemicellulases. A variety of hemicellulases have been identified from mesophilic and thermophilic microorganisms. First prominent industrial application of a hemicellulase was in the area of pulp biobleaching when xylanases were found to be able to reduce use of toxic chlorine oxide. Later many applications of hemicellulases in various areas such as deinking of paper waste, clarification of fruit juices, upgradation of feed, fodder and fibres, and saccharification were revealed. The present review presents an overview of patents related to hemicellulases including xylanases, mannanases, arabionosidases, acetylxylan esterases (AXE) and other accessory enzymes.

Ionizing radiation-induced Acute Radiation Syndrome (ARS) can be prevented/treated using radioprotective agents including; radioprotectors, radiomitigators and radio-therapeutics. Most of the radioprotective molecules currently being developed have emerged from classical drug discovery approaches and have certain shortcomings related to efficacy and toxicity. In order to overcome these issues, adoption of new target-based drug development approaches is required. Like other pharmaceutical drug development programs, patents are being used to protect the new radioprotective compounds that provide right of exclusivity to the inventors. In addition to patents, the FDA approval for safety and efficacy is required for the development of radioprotective drugs that is often being done under FDA’s animal rule and requires huge amount of funding. However, radiation countermeasure agents considered emergency medicines and not carrying attractive revenue generation opportunities and are often granted ‘orphan drug status’. Thus, pharma giants do not take much interest in such molecules that limit the funding options only to the government agencies, which in turn reduces the interest of researchers in this particular area. In addition to their emergency use, these agents could also be employed for clinical radiotherapy purposes and may provide reasonable incentive to the inventor. Thus, encouraging the development of new radioprotective agent with cutting-edge drug discovery approaches needs more public-private partnership ensuring affordable access; that may stimulate researchers to engage in the area of radioprotector development. This article attempts to cover information available so far on the products/patents/major compounds, known in this critical area of development, along with most relevant regulatory issues and future perspectives.

Tannin acyl hydrolase (E.C. 3.1.1.20) commonly referred as tannase, is a hydrolytic enzyme that catalyses the hydrolysis of ester bonds present in gallotannins, ellagitannins, complex tannins and gallic acid esters. Tannases are the important group of botechnologically relevant enzymes distributed throughout the animal, plant and microbial kingdoms. However, microbial tannases are currently receiving a great deal of attention. Tannases are extensively used in food, feed, pharmaceutical, beverage, brewing and chemical industries. Owing to its diverse area of applications, a number of patents have been appeared in the recent past. The present review pretends to present the advances and perspectives in the industrial application of tannase with special emphasis on patents.

Chitin is an extremely insoluble material with very limited industrial use; however it can be deacetylated to soluble chitosan which has a wide range of applications. The enzymatic deacetylation of various chitin samples was investigated using the bacterial chitin deacetylase (CDA), which was partially purified from Alcaligenes sp. ATCC 55938 growth medium and the kinetic parameters of the enzyme were determined. Also, the efficiency of biocatalyst recycling by immobilization technique was examined. CDA activity reached its maximum (0.419 U/ml) after 18 h of bacterial cultivation. When glycol chitin was used as a substrate, the optimum pH of the enzyme was estimated to be 6 after checking a pH range between 3 and 9, while the optimum temperature was found to be 35°C. Addition of acetate (100 mM) in the assay mixture resulted in 50% loss of enzyme activity. The Km value of the enzyme is 1.6 × 10-4 µM and Vmax is 24.7 µM/min. The average activity of CDA was 0.38 U/ml for both of immobilized and freely suspended cells after 18 h of bacterial growth. Some related patents are also discussed here.