Tyrosinase from the pulps of local cultivars of Musa spp: Purification, characterization, immobilization, and application in the batch production of l-3,4-dihydroxyphenylalanine.

Tyrosinase, an enzyme involved in browning reactions in plants/crops exposed to mechanical injury, was isolated from the pulp of some different locally available bananas (M. cavendish, M. acuminata, and M. paradisiaca). Tyrosinase from the pulps was extracted, purified, immobilized, and characterized. Thereafter, the potentials of the immobilized tyrosinase in the possible production of l-3,4-dihydroxyphenylalanine (L-DOPA) in an improvised batch reactor was exploited using tyrosine and ascorbate as the substrates. L-DOPA production was monitored via thin-layer chromatography and spectrophotometry (Arnow's method). L-DOPA is a drug that is used in the treatment of Parkinson's disease. Hence, this study exploited a non-chemical route for its synthesis using the tyrosinase obtained from the banana pulps. The purified tyrosinase had an optimum pH and temperature of 6.5 and 7.0, respectively. The molecular weight of the purified tyrosinase was 45 kDa. Quercetin and resorcinol both competitively inhibited the purified tyrosinase from the three cultivars. Immobilized M. cavendish tyrosinase produced the highest concentration (0.60 mM) of L-DOPA after 8 h in an improvised batch reactor. The tyrosinase in the banana pulps serves as a cheap and readily available green route for the possible production of L-DOPA.

Susceptibility of cytoskeletal-associated proteins for tumor progression.

The traditional functions of cytoskeletal-associated proteins (CAPs) in line with polymerization and stabilization of the cytoskeleton have evolved and are currently underrated in oncology. Although therapeutic drugs have been developed to target the cytoskeletal components directly in cancer treatment, several recently established therapeutic agents designed for new targets block the proliferation of cancer cells and suppress resistance to existing target agents. It would seem like these targets only work toward inhibiting the polymerization of cytoskeletal components or hindering mitotic spindle formation in cancer cells, but a large body of literature points to CAPs and their culpability in cell signaling, molecular conformation, organelle trafficking, cellular metabolism, and genomic modifications. Here, we review those underappreciated functions of CAPs, and we delineate the implications of cellular signaling instigated by evasive properties induced by aberrant expression of CAPs in response to stress or failure to exert normal functions. We present an analogy establishing CAPs as vulnerable targets for cancer systems and credible oncotargets. This review establishes a paradigm in which the cancer machinery may commandeer the conventional functions of CAPs for survival, drug resistance, and energy generation; an interesting feature overdue for attention.

Hypolipidemic effects of lactic acid bacteria fermented cereal in rats.

BACKGROUND: The objectives of the present study were to investigate the efficacy of the mixed culture of Lactobacillus acidophilus (DSM 20242), Bifidobacterium bifidum (DSM 20082) and Lactobacillus helveticus (CK60) in the fermentation of maize and the evaluation of the effect of the fermented meal on the lipid profile of rats. METHODS: Rats were randomly assigned to 3 groups and each group placed on a Diet A (high fat diet into which a maize meal fermented with a mixed culture of Lb acidophilus (DSM 20242), B bifidum (DSM 20082) and Lb helveticus (CK 60) was incorporated), B (unfermented high fat diet) or C (commercial rat chow) respectively after the first group of 7 rats randomly selected were sacrificed to obtain the baseline data. Thereafter 7 rats each from the experimental and control groups were sacrificed weekly for 4 weeks and the plasma, erythrocytes, lipoproteins and organs of the rats were assessed for cholesterol, triglyceride and phospholipids. RESULTS: Our results revealed that the mixed culture of Lb acidophilus (DSM 20242), B bifidum (DSM 20082) and Lb helveticus (CK 60) were able to grow and ferment maize meal into 'ogi' of acceptable flavour. In addition to plasma and hepatic hypercholesterolemia and hypertriglyceridemia, phospholipidosis in plasma, as well as cholesterogenesis, triglyceride constipation and phospholipidosis in extra-hepatic tissues characterized the consumption of unfermented hyperlipidemic diets. However, feeding the animals with the fermented maize diet reversed the dyslipidemia. CONCLUSION: The findings of this study indicate that consumption of mixed culture lactic acid bacteria (Lb acidophilus (DSM 20242), Bifidobacterium bifidum (DSM 20082) and Lb helveticus (CK 60) fermented food results in the inhibition of fat absorption. It also inhibits the activity of HMG CoA reductase. This inhibition may be by feedback inhibition or repression of the transcription of the gene encoding the enzyme via activation of the sterol regulatory element binding protein (SREBP) transcription factor. It is also possible that consumption of fermented food enhances conversion of cholesterol to bile acids by activating cholesterol-7α-hydroxylase.