Characterization of Corrinoid Compounds in the Edible Cyanobacterium &amp;lt;i&amp;gt;Nostoc flagelliforme&amp;lt;/i&amp;gt; the Hair Vegetable

Fei Teng,Yukinori Yabuta,Fumio Watanabe,Yuji Yamaguchi,Tomohiro Bito,Hiroyuki Takenaka,Shigeo Takenaka

doi:10.4236/fns.2014.54040

Abstract

Vitamin B12 contents in the edible cyanobacterium Nostoc flagelliforme, also known as hair vegetable, were assayed using a microbiological method. We detected high vitamin B12 contents in samples of naturally grown cells (109.2 ± 18.5 μg/100g dry weight) and cultured cells (120.2 ± 53.6 μg/100g dry weight). However, commercially available hair vegetable samples, which comprised fake substitutes and Nostoc, had variable contents (4.8 - 101.6 μg/100g dry weight) because concomitant fake items contain very low vitamin B12 contents. To evaluate whether natural and cultured N. flagelliforme samples contained vitamin B12 or pseudovitamin B12, corrinoid compounds were purified and identified as pseudovitamin B12 (approximately 72%) and vitamin B12 (approximately 28%) using silica gel 60 TLC bioautography and LC/MS. The results suggested that N. flagelliforme contains substantial amounts of pseudovitamin B12, which is inactive in humans.

Highlights

Nostoc flagelliforme is an edible cyanobacterium, which grows naturally in some semidesert regions of China and Mongolia
Several studies [5,6] have reported that most of the corrinoids found in certain edible cyanobacteria may not be bioavailable in mammals
Nostoc flagelliforme the Hair Vegetable which is inactive in humans, is the predominant corrinoid in the edible cyanobacteria used as a health food by humans

Summary

Introduction

Nostoc flagelliforme is an edible cyanobacterium, which grows naturally in some semidesert regions of China and Mongolia. Takenaka et al, [4] demonstrated the oral acute and subacute safety of dried N. flagelliforme in rats. Nostoc flagelliforme the Hair Vegetable which is inactive in humans, is the predominant corrinoid in the edible cyanobacteria used as a health food by humans. N. flagelliforme, hair vegetable, is already used as health food, but there is no information on about B12 contents in pure N. flagelliforme and commercially available hair vegetable, or whether the corrinoids are authentic B12 or inactive corrinoids. We characterized corrinoid compounds from N. flagelliforme sources, including naturally grown samples, cultured samples, and commercially available hair vegetable samples

Materials

Vitamin B12 Contents

Relative Content Ratios of B12 and Pseudo B12 in Various Nostoc Samples