Baljinder Kaur

Biotechnological and Molecular Approaches for Vanillin Production: a Review

Vanillin is one of the most widely used flavoring agents in the world. As the annual world market demand of vanillin could not be met by natural extraction, chemical synthesis, or tissue culture technology, thus biotechnological approaches may be replacement routes to make production of bio-vanillin economically viable. This review’s main focus is to highlight significant aspects of biotechnology with emphasis on the production of vanillin from eugenol, isoeugenol, lignin, ferulic acid, sugars, phenolic stilbenes, vanillic acid, aromatic amino acids, and waste residues by applying fungi, bacteria, and plant cells. Production of biovanillin using GRAS lactic acid bacteria and metabolically engineered microorganisms, genetic organization of vanillin biosynthesis operons/gene cassettes and finally the stability of biovanillin generated through various biotechnological procedures are also critically reviewed in the later sections of the review.

Involvement of PPAR-gamma in curcumin-mediated beneficial effects in experimental dementia

The present study was undertaken to investigate the possible mechanism of curcumin-mediated beneficial effects in memory deficits associated with experimental dementia. Dementia was induced in Swiss albino mice by administrating streptozotocin (3 mg kg−1) intracerebroventricularly on first and third day. Morris water maze test was employed to assess learning and memory of the animals. Biochemical analysis of brain homogenate was performed to assess brain acetyl cholinesterase (AChE) activity and total oxidative stress. Streptozotocin (STZ) produced a significant decrease in water maze performance of mice indicative of impairment in spatial reference memory. Curcumin (20 mg/kg p.o. daily for 14 days) successfully attenuated STZ-induced memory deficits. Higher levels of brain AChE activity and oxidative stress were observed in STZ-treated animals, which were significantly attenuated by curcumin. Furthermore, the noted beneficial effect of curcumin on STZ-induced dementia was significantly abolished by pretreatment with PPAR-γ receptor antagonist bisphenol-A-diglycidyl ether, i.e., BADGE (30 mg/kg intraperitoneally (i.p.)). It may be concluded that the beneficial effects of curcumin are mediated through the activation of PPAR-γ receptors.

Exploring mechanism of pioglitazone‐induced memory restorative effect in experimental dementia

The present study was undertaken to investigate possible mechanism of pioglitazone‐induced beneficial effect in memory deficits associated with experimental dementia. Dementia was induced in Swiss albino mice by administration of streptozotocin (STZ; 3u2003mg/kg administered intracerebroventricularly on 1st & 3rd day). Morris Water‐Maze test was employed to assess learning and memory of the animals. Brain acetylcholinesterase (AChE) activity was measured by Ell Mann’s method. Brain thiobarbituric acid reactive species (TBARS) levels and reduced glutathione (GSH) levels were measured by Ohokawa’s and Beutler’s method respectively to assess total oxidative stress. Blood glucose level was also measured. Streptozotocin (STZ) produced a significant decrease in water‐maze performance of mice hence reflecting loss of learning and memory. Pioglitazone (20u2003mg/kg p.o. daily for 14u2003days) successfully attenuated STZ‐induced memory deficits, without any significant per se effect on blood glucose levels. Higher levels of brain AChE activity, TBARS and lower levels of GSH were observed in STZ treated animals, which were significantly attenuated by pioglitazone. Further, the noted beneficial effect of pioglitazone on STZ‐induced dementia was significantly abolished by pre‐treatment of nitric oxide (NO) synthase inhibitor l‐NAME (3u2003mg/kg i.p.) manifested in the terms of decrease in water‐maze performance and increase in brain AChE activity as well as oxidative stress. It is concluded that anti‐dementic effect of pioglitazone may involve central cholinergic, oxidative and NO pathways.

Biomedical Applications of Fermenticin HV6b Isolated from Lactobacillus fermentum HV6b MTCC10770

Fermenticin HV6b is a class IIa antimicrobial peptide produced by Lactobacillus fermentum HV6b MTCC 10770 isolated from human vaginal ecosystem. It shows growth inhibition of a wide range of opportunistic pathogens of humans, for example, Bacteroides, Gardnerella vaginalis, Mobiluncus, Staphylococci, and Streptococci, associated with bacterial vaginosis in humans. It does possess an impressive sperm immobilization and spermicidal activity tested against human sperms which makes it an attractive proposition for formulating antibacterial vaginosis and contraceptive products. Apart from this, in vitro studies conducted against four different tissue models have indicated its potential to be used as a component of anticancerous drug therapy as it is reported to induce apoptosis in cancerous cells. This information could be integrated in future studies focusing on in vivo assessment of anticancerous activity of lactic acid bacterial toxins or bacteriocins.

Phenolic Biotransformations during Conversion of Ferulic Acid to Vanillin by Lactic Acid Bacteria

Vanillin is widely used as food additive and as a masking agent in various pharmaceutical formulations. Ferulic acid is an important precursor of vanillin that is available in abundance in cell walls of cereals like wheat, corn, and rice. Phenolic biotransformations can occur during growth of lactic acid bacteria (LAB), and their production can be made feasible using specialized LAB strains that have been reported to produce ferulic acid esterases. The present study aimed at screening a panel of LAB isolates for their ability to release phenolics from agrowaste materials like rice bran and their biotransformation to industrially important compounds such as ferulic acid, 4-ethyl phenol, vanillic acid, vanillin, and vanillyl alcohol. Bacterial isolates were evaluated using ferulic acid esterase, ferulic acid decarboxylase, and vanillin dehydrogenase assays. This work highlights the importance of lactic acid bacteria in phenolic biotransformations for the development of food grade flavours and additives.

Biotransformation of rice bran to ferulic acid by pediococcal isolates.

Ferulic acid (FA) is widely used in foods, in beverages, and in various pharmaceutical industries as a precursor of vanillin. FA biotransformation can occur during the growth of lactic acid bacteria (LAB), and its conversion to other phenolic derivatives is observed by many scientists, where ferulic acid esterase (FAE) and ferulic acid decarboxylase (FDC) play significant roles. The present study aimed at screening a panel of LAB for their ability to release FA from rice bran, an agro waste material. FAE and FDC activities were analyzed for the preliminary screening of various dairy isolates. Two Pediococcus acidilactici isolates were selected for studying further the hydrolysis of FA from rice bran and its bioconversion into phenolic derivatives like 4-ethylphenol, vanillin, vanillic acid, and vanillyl alcohol. P. acidilactici M16, a probiotic isolate, has great potential for the production of FA from rice bran and could be exploited as starter culture in the food industry for the production of biovanillin.

Statistical Optimization of Conditions for Decolorization of Synthetic Dyes by Cordyceps militaris MTCC 3936 Using RSM

In the present study, the biobleaching potential of white rot fungus Cordyceps militaris MTCC3936 was investigated. For preliminary screening, decolorization properties of C. militaris were comparatively studied using whole cells in agar-based and liquid culture systems. Preliminary investigation in liquid culture systems revealed 100% decolorization achieved within 3 days of incubation for reactive yellow 18, 6 days for reactive red 31, 7 days for reactive black 8, and 11 days for reactive green 19 and reactive red 74. RSM was further used to study the effect of three independent variables such as pH, incubation time, and concentration of dye on decolorization properties of cell free supernatant of C. militaris. RSM based statistical analysis revealed that dye decolorization by cell free supernatants of C. militaris is more efficient than whole cell based system. The optimized conditions for decolorization of synthetic dyes were identified as dye concentration of 300 ppm, incubation time of 48 h, and optimal pH value as 5.5, except for reactive red 31 (for which the model was nonsignificant). The maximum dye decolorizations achieved under optimized conditions for reactive yellow 18, reactive green 19, reactive red 74, and reactive black 8 were 73.07, 65.36, 55.37, and 68.59%, respectively.

Metabolic engineering of Pediococcus acidilactici BD16 for production of vanillin through ferulic acid catabolic pathway and process optimization using response surface methodology

Occurrence of feruloyl-CoA synthetase (fcs) and enoyl-CoA hydratase (ech) genes responsible for the bioconversion of ferulic acid to vanillin have been reported and characterized from Amycolatopsis sp., Streptomyces sp., and Pseudomonas sp. Attempts have been made to express these genes in Escherichia coli DH5α, E. coli JM109, and Pseudomonas fluorescens. However, none of the lactic acid bacteria strain having GRAS status was previously proposed for heterologous expression of fcs and ech genes for production of vanillin through biotechnological process. Present study reports heterologous expression of vanillin synthetic gene cassette bearing fcs and ech genes in a dairy isolate Pediococcus acidilactici BD16. After metabolic engineering, statistical optimization of process parameters that influence ferulic acid to vanillin biotransformation in the recombinant strain was carried out using central composite design of response surface methodology. After scale-up of the process, 3.14xa0mM vanillin was recovered from 1.08 mM ferulic acid per milligram of recombinant cell biomass within 20xa0min of biotransformation. From LCMS-ESI spectral analysis, a metabolic pathway of phenolic biotransformations was predicted in the recombinant P. acidilactici BD16 (fcs+/ech+).

Effect of the oral intake of probiotic Pediococcus acidilactici BA28 on Helicobacter pylori causing peptic ulcer in C57BL/6 mice models.

Probiotic lactic acid bacteria are being proposed to cure peptic ulcers by reducing colonization of Helicobacter pylori within the stomach mucosa and by eradicating already established infection. In lieu of that, in vitro inhibitory activity of pediocin-producing probiotic Pediococcus acidilactici BA28 was evaluated against H. pylori by growth inhibition assays. Further, chronic gastritis was first induced in two groups of C57BL/6 mice by orogastric inoculation with H. pylori with polyethylene catheter, and probiotic P. acidilactici BA28 was orally administered to study the eradication and cure of peptic ulcer disease. H. pylori and P. acidilactici BA28 were detected in gastric biopsy and fecal samples of mice, respectively. A probiotic treatment with P. acidilactici BA28, which is able to eliminate H. pylori infection and could reverse peptic ulcer disease, is being suggested as a co-adjustment with conventional antibiotic treatment. The study provided an evidence of controlling peptic ulcer disease, by diet modulation.

In Vitro Cytotoxicity of Native and Rec-Pediocin CP2 Against Cancer Cell Lines: A Comparative Study

Pediocin CP2 is a natural antimicrobial peptide produced by Pediococcus acidilactici MTCC 5101. Its recombinant version was created by employing computational protein engineering approach and was expressed as a synthetic fusion protein in recombinant E. coli BL21(DE3)-pedA. Both native and rec-pediocin were comparatively evaluated for their cytotoxicity against HepG2 (a hepatocarcinoma cell line), HeLa (a cervical adenocarcinoma), MCF7 (a mammary gland adenocarcinoma) and Sp2/0-Ag14 (a spleen lymphoblast) cell lines. Inhibition of cell proliferation was quantitated by MTT assay and induction of apoptosis was studied by genomic DNA fragmentation assay. Results indicated a significantly higher cytotoxicity of rec-pediocin and damage of chromosomal DNA in bacteriocin tested cell lines.