Using Caenorhabditis elegans as a model animal, we evaluated the effects of chronical supplementation with high-dose folic acid on physiological events such as life cycle and egg-laying capacity and folate metabolism. Supplementation of high-dose folic acid significantly reduced egg-laying capacity. The treated worms contained a substantial amount of unmetabolized folic acid and exhibited a significant downregulation of the mRNAs of cobalamin-dependent methionine synthase reductase and 5,10-methylenetetrahydrofolate reductase. In vitro experiments showed that folic acid significantly inhibited the activity of cobalamin-dependent methionine synthase involved in the metabolism of both folate and methionine. In turn, these metabolic disorders induced the accumulation of unmetabolized homocysteine, leading to severe oxidative stress in worms. These results were similar to the phenomena observed in mammals during folate deficiency.

The vitamin B 12 content of lobster, crayfish, crab, and shrimp viscera was determined using a microbiological assay based on Lactobacillus delbrueckii subsp. lactis ATCC7830. These viscera contained high vitamin B 12 levels (7.2−118.6 μg/100 g of wet weight). We purified vitamin B 12 compounds from the extracts of these viscera using an immunoaffinity column. Corrinoid compounds were identified using liquid chromatography-electrospray ionization tandem mass spectrometry. The viscera tested contained vitamin B 12 -b-, -d-, and -e-monocarboxylic acids and vitamin B 12 -be-dicarboxylic acid, modified with peripheral propionamide side chains of the corrin ring. These vitamin B 12 carboxylic acids are specifically located in the viscera edible portions of lobster, crayfish, crab, and shrimp.

No abstract

Pear juice concentrate prepared by boiling Japanese pear (Pyrus pyrifolia Nakai cv. Nijisseiki) juice can significantly inhibit the activity of tyrosinase, a key enzyme in melanin synthesis in human skin. Using the ethanol extract of pear juice concentrate, we homogeneously purified an active compound that was identified as 5-hydroxymethyl-2-furaldehyde (5-HMF) through 1H- and 13C-NMR and mass spectroscopy. We observed that 5-HMF inhibited the monophenolase and diphenolase activities of mushroom tyrosinase as a mixed-type inhibitor (Ki values of 3.81 and 3.70 mmol/L, respectively). In B16 mouse melanoma cells, treatment with 170 µmol/L of 5-HMF significantly reduced α-melanocyte-stimulated melanin synthesis by suppressing the cyclic adenosine monophosphate-dependent signaling pathway involved in melanogenesis. The results of our study indicated that 5-HMF can be potentially used as a skin-lightening agent in the cosmetic industry. Abbreviations: AC: adenylate cyclase; CREB: cAMP response element-binding protein; dhFAME: S-(−)-10,11-Dihydroxyfarnesoic acid methyl ester; DMEM: dulbecco′s modified eagle medium; l-DOPA: 3-(3,4-Dihydroxyphenyl)- l-alanine; GAPDH: glyceraldehyde-3-phosphate dehydrogenase; HEPES: 4-(2-Hydroxyethyl)-1-piperazine ethane sulfonic acid; 5-HMF: 5-Hydroxymethyl-2-furaldehyde; MITF: microphthalmia-associated transcription factor; α-MSH: α-Melanocyte-stimulating hormone; PKA: protein kinase A; PVDF: polyvinylidene difluoride; SDS: sodium dodecyl sulfate; TRP1: tyrosinase-related protein 1; TRP2: tyrosinase-related protein 2

(1) Background: Currently, no data are available on the vitamin B12 content of an organic fertilizer product, viz. fermented poultry manure, or whether the organic fertilizer product contains vitamin B12 or inactive corrinoids (or both). (2) Methods: This study conducted a microbiological assay to determine the vitamin B12 content of various commercially available fermented poultry manure fertilizer products. (3) Results: The results varied from 1.4 μg to approximately 20 μg per 100 g of dry weight. In the bioautography analysis, selected products had two positive spots with identical Rf values of vitamin B12 and pseudovitamin B12. High-performance liquid chromatography and liquid chromatography/electrospray ionization−mass spectrometry analyses of the selected products indicated that these fertilizers primarily contained vitamin B12. They also contained minor inactive cobamides such as pseudovitamin B12, 2-methyladenyl cobamide, and 2-methylmercaptoadenyl cobamide. (4) Conclusions: These results suggested that edible plants would enrich vitamin B12 using fermented poultry manure organic fertilizer products.

BACKGROUND Vitamin B12 is an essential vitamin that is absent in plant‐derived foods such as fruits and vegetables. This can result in an increased risk of developing vitamin B12 deficiency in strict vegetarians (vegans). There are several studies that have aimed to enhance nutrients in food crops. The purpose of the present study was to fortify tomato fruits with vitamin B12 (or cyanocobalamin). RESULTS Tomato plants were grown for 70 days in hydroponic culture pots and treated with 5 μm of cyanocobalamin on days 1–24 after the fruiting, and then harvested for tomato fruits. The ripened tomato fruits contained 4.0 × 10−7 g of cyanocobalamin per 100 g of dry weight and showed a significant increase in glucose and lycopene levels. CONCLUSION The present study highlights the use of a cyanocobalamin–supplementation system for the production of B12 fortified tomato fruits that can help prevent B12 deficiency in vegetarians. © 2022 Society of Chemical Industry.

No abstract

No abstract