Folate derivatives, 5-methyltetrahydrofolate and 10-formyltetrahydrofolate, protect BEAS-2B cells from high glucose-induced oxidative stress and inflammation.

Folate (vitamin B9) and its biologically active derivatives are well-known antioxidant molecules protecting cells from oxidative degradation. The presence of high glucose, often found in diabetic patients, causes oxidative stress resulting in cellular stress and inflammatory injury. Cells in organs such as the lung are highly prone to inflammation, and various protective mechanisms exist to prevent the progressive disorders arising from inflammation. In the present study, the synthetic form of folate, i.e. folic acid, and active forms of folate, i.e. 5-methyltetrahydrofolate and 10-formyltetrahydrofolate, were evaluated for their antioxidant and antiinflammatory potential against high glucose (50 mM)-mediated oxidative stress and inflammation in BEAS-2B cells, an immortalised bronchial epithelial cell line. High glucose treatment showed a 67% reduction in the viability of BEAS-2B cells, which was restored to the viability levels seen in control cultures by the addition of active folate derivatives to the culture media. The DCFH-DA fluorometric assay was performed for oxidative stress detection. The high glucose-treated cells showed a significantly higher fluorescence intensity (1.81- and 3.8-fold for microplate assay and microscopic observation, respectively), which was normalised to control levels on supplementation with active folate derivatives. The proinflammatory NF-κB p50 protein expression in the active folate derivative-supplemented high glucose-treated cells was significantly lower compared to the folic acid treatment. In support of these findings, in silico microarray GENVESTIGATOR database analysis showed that in bronchiolar small airway epithelial cells exposed to inflammatory condition, folate utilization pathway genes are largely downregulated. However, the folate-binding protein gene, which encodes to the folate receptor 1 (FOLR1), is significantly upregulated, suggesting a high demand for folate by these cells  in inflammatory situations. Supplementation of the active folate derivatives 5-methyltetrahydrofolate and 10-formyltetrahydrofolate resulted in significantly higher protection over the folic acid from high glucose-induced oxidative stress and inflammation. Therefore, the biologically active folate derivatives could be a suitable alternative over the folic acid for alleviating inflammatory injury-causing oxidative stress.

Improvement in vitamin B12 status of Wistar rats by supplementing the diet with Chlorella vulgaris biomass.

The sources of bioavailable vitamin B12 are limited, and most of them are animal-derived. Chlorella vulgaris, a freshwater microalga, is known for immune system boosting, nutraceutical properties and presence of a natural form of vitamin B12. The present study focused on the in vivo evaluation of the Chlorella biomass as a source of bioavailable vitamin B12 to alleviate the vitamin B12 deficiency status of Wistar rats. Experimental animals were evaluated for the vitamin B12 deficiency-related circulatory marker (serum vitamin B12) and functional markers (plasma homocysteine and urinary methylmalonic acid), haematological and histological changes. The results showed that an increase of 2.4-fold in urinary methylmalonic acid (13.01 ± 0.89 µmoles moles of creatinine-1), 2.6-fold in plasma homocysteine (17.18 ± 3.57 µmole L-1), and 48% decrease in serum vitamin B12 levels (252.69 ± 1.46 pg mL-1) in vitamin B12 deficient group compared to control animals. The Chlorella biomass supplementation in the diet led to the restoration of the functional and circulatory markers, hematological parameters, and vitamin B12 content of kidney and liver to control levels. The Chlorella biomass supplementation increased the erythrocyte precursors and MAST cells in the bone marrow and also normalized the histological features of kidney, liver, and lung tissues. The results suggest that the vitamin B12 from the Chlorella biomass was bioavailable and facilitated the improvement of vitamin B12 status in deficient rats.

Comparative life cycle assessment of autotrophic cultivation of Scenedesmus dimorphus in raceway pond coupled to biodiesel and biogas production.

Life cycle assessment (LCA) of indigenous freshwater microalgae, Scenedesmus dimorphus, cultivation in open raceway pond and its conversion to biodiesel and biogas were carried out. The LCA inventory inputs for the biogas scenario was entirely based on primary data obtained from algal cultivation (in pilot scale raceway pond), harvesting, and biogas production; while only the downstream processing involved in biodiesel production namely drying, reaction and purification were based on secondary data. Overall, eight scenarios were modeled for the integrated process involving: algae-based CO2 capture and downstream processing scenarios for biodiesel and biogas along with impact assessment of nutrient addition and extent of recycling in a life cycle perspective. The LCA results indicated a huge energy deficit and net CO2 negative in terms of CO2 capture for both the biodiesel and biogas scenarios, majorly due to lower algal biomass productivity and higher energy requirements for culture mixing. The sensitivity analysis indicated that variability in the biomass productivity has predominant effect on the primary energy demand and global warming potential (GWP, kg CO2 eq.) followed by specific energy consumption for mixing algal culture. Furthermore, the LCA results indicated that biogas conversion route from microalgae was more energy efficient and sustainable than the biodiesel route. The overall findings of the study suggested that microalgae-mediated CO2 capture and conversion to biodiesel and biogas production can be energy efficient at higher biomass productivity (> 10 g m-2 day-1) and via employing energy-efficient systems for culture mixing (< 2 W m-3).

Improvement of vitamin B12 status with Spirulina supplementation in Wistar rats validated through functional and circulatory markers.

Spirulina evaluated as a source of vitamin B12 through the modulation of vitamin B12 deficiency mediated physiological and biochemical changes in experimental animals. The B12 deficient male weanling Wistar rats were fed with Spirulina-supplemented diet for 10 weeks. An increase in urinary methylmalonic acid (22.70 ± 4.08 µmol/moles of creatinine) and plasma homocysteine (16.55 ± 0.48 µmol/L) levels in the B12 deficient group was observed, while these were equal to control in the Spirulina fed group (8.71 ± 0.48 µmol/mol of creatinine and 6.88 ± 1.18 µmol/L, respectively). The vitamin B12 levels in serum (874.27 ± 89.69), plasma (615.53 ± 26.5 pg/ml), kidney (10.19 ± 1.066 ng/g), and liver tissues (6.37 ± 0.62 ng/g) in the Spirulina fed group were similar to control. Severe atrophic changes in the testes and altered tissue architecture in lung and spleen as seen in the B12 deficient group were normalized in the Spirulina fed group. The study validates that Spirulina can improve the vitamin B12 status. PRACTICAL APPLICATIONS: The present study showed that the supplementation of Spirulina in the diet of vitamin B12 deficient rats leads to the normalization of vitamin B12 deficiency-induced circulatory and functional biomarkers along with biochemical and histological changes. Vegetarian sources for vitamin B12 are limited and the results presented here provide scientific validation for the use of Spirulina as a potential vegetarian source of bioavailable vitamin B12 .