GERBAM — Deuxième Colloque International de Bactériologie marine — CNRS, Brest, 1-5 octobre 1984
IFREMER, Actes de Colloques, 3, 1986, pp. 169-173
18
PRODUCTION AND CONSUMPTION OF B GROUP VITAMINS IN SITU
A. KURATA
Lake Biwa Research Institute, Vehide-Hama, OTSU, Shiga 520, (JAPAN)
ABSTRACT - The changes in concentration of thiamine, biotin and vitamin B 12 in water of the soaked bottles for
6 hr in situ in the north basin of Lake Biwa were examined successively over 30 hours. The concentrations of the
vitamins changed comparatively during 6 hours soaking in situ. Generally, the concentrations of thiamine,
biotin and vitamin Bu were in high levels in the morning and in low levels in the evening both in the soaked
bottles and in the surrounding water. The fluctuation ranges in concentration of vitamins in a 5 m deep layer
were greater than those in thermocline. From the data obtained with the soaked bottles in situ, it was supposed
that the decrease of vitamins in concentration during the daytime was attribute to surpass the consumption of
vitamins by phytoplankton rather than the production, on the contrary the increase of vitamins in concentration
during the night time was attribute to surpass the autochthonous production of vitamins by various kinds of
microorganisms than the consumption of vitamins by phytoplankton. The averaged consumption rates of
thiamine, biotin and vitamins Bu in concentration in situ were 4.50,0.61 and 0.62 mµg/l/h, on the other hand,
the averaged production rates of these vitamins were 4.32, 0.43 and 0.95 mµg/l/h, respectively. Bacteria
producing vitamins by them was further examined. Some of the bacteria produced two or three kinds of
vitamins simultaneously.
Key words: bacteria, freshwater, production of vitamins.
RÉSUMÉ - Les variations des concentrations en thiamine, biotine et vitamine B 12 dans l’eau des bouteilles
immergées in situ pendant 6 heures dans le bassin nord du lac Biwa ont été suivies sur 30 heures. Les
concentrations en vitamines varient de façon comparable durant les 6 heures d’immersion. Généralement les
concentrations en thiamine, biotine et vitamine B 12 présentent des taux élevés le matin et bas le soir, ceci dans les
bouteilles immergées comme dans l’eau de mer environnante. Les concentrations en vitamines varient plus dans
une couche de 5 m qu’au niveau de la thermocline. A partir des données obtenues par les bouteilles immergées in
situ, il est supposé que la diminution diurne de la concentration en vitamines serait due à leur excès de
consommation par le phytoplancton. Au contraire, l’augmentation nocturne des concentrations en vitamines
serait attribuable à leur production par différents microorganismes. Les taux moyens de consommation de
thiamine, biotine et vitamine Bu in situ sont respectivement de 4.50, 6.61 et 0.62 mµg/l/h; ceux de leur
production de 4.32, 0.43 et 0.95 mµg/ l/h. Les bactéries produisant des vitamines sont plus particulièrement
examinées. Certaines d’entre elles produisent simultanément deux ou trois sortes de vitamines.
Mots clés: bactéries, eau douce, production de vitamines.
INTRODUCTION
We have previously reported a successive diurnal change and a periodical diurnal rhythm
in the concentration of B group vitamins having an inverse correlation to the phytoplankton population in the waters of the southern basin of Lake Biwa (Kurata A. et al., 1982).
However, it is necessary to clarify the short term continual fluctuation in the concentration of B group vitamins in an in situ closed system, in order to more clearly elucidate the
interrelationship of the autochthonous vitamin production by microorganisms, and the
consumption by phytoplankton requiring these vitamins, without allochthonous vitamin
supply and water turbulence. Few reports have been published concerning the successive
diurnal changes, and the continual fluctuations in the concentration of B group vitamins
169
IFREMER, Actes de Colloques, 3, 1986, pp. 169-173
18
PRODUCTION AND CONSUMPTION OF B GROUP VITAMINS IN SITU
A. KURATA
Lake Biwa Research Institute, Vehide-Hama, OTSU, Shiga 520, (JAPAN)
ABSTRACT - The changes in concentration of thiamine, biotin and vitamin B 12 in water of the soaked bottles for
6 hr in situ in the north basin of Lake Biwa were examined successively over 30 hours. The concentrations of the
vitamins changed comparatively during 6 hours soaking in situ. Generally, the concentrations of thiamine,
biotin and vitamin Bu were in high levels in the morning and in low levels in the evening both in the soaked
bottles and in the surrounding water. The fluctuation ranges in concentration of vitamins in a 5 m deep layer
were greater than those in thermocline. From the data obtained with the soaked bottles in situ, it was supposed
that the decrease of vitamins in concentration during the daytime was attribute to surpass the consumption of
vitamins by phytoplankton rather than the production, on the contrary the increase of vitamins in concentration
during the night time was attribute to surpass the autochthonous production of vitamins by various kinds of
microorganisms than the consumption of vitamins by phytoplankton. The averaged consumption rates of
thiamine, biotin and vitamins Bu in concentration in situ were 4.50,0.61 and 0.62 mµg/l/h, on the other hand,
the averaged production rates of these vitamins were 4.32, 0.43 and 0.95 mµg/l/h, respectively. Bacteria
producing vitamins by them was further examined. Some of the bacteria produced two or three kinds of
vitamins simultaneously.
Key words: bacteria, freshwater, production of vitamins.
RÉSUMÉ - Les variations des concentrations en thiamine, biotine et vitamine B 12 dans l’eau des bouteilles
immergées in situ pendant 6 heures dans le bassin nord du lac Biwa ont été suivies sur 30 heures. Les
concentrations en vitamines varient de façon comparable durant les 6 heures d’immersion. Généralement les
concentrations en thiamine, biotine et vitamine B 12 présentent des taux élevés le matin et bas le soir, ceci dans les
bouteilles immergées comme dans l’eau de mer environnante. Les concentrations en vitamines varient plus dans
une couche de 5 m qu’au niveau de la thermocline. A partir des données obtenues par les bouteilles immergées in
situ, il est supposé que la diminution diurne de la concentration en vitamines serait due à leur excès de
consommation par le phytoplancton. Au contraire, l’augmentation nocturne des concentrations en vitamines
serait attribuable à leur production par différents microorganismes. Les taux moyens de consommation de
thiamine, biotine et vitamine Bu in situ sont respectivement de 4.50, 6.61 et 0.62 mµg/l/h; ceux de leur
production de 4.32, 0.43 et 0.95 mµg/ l/h. Les bactéries produisant des vitamines sont plus particulièrement
examinées. Certaines d’entre elles produisent simultanément deux ou trois sortes de vitamines.
Mots clés: bactéries, eau douce, production de vitamines.
INTRODUCTION
We have previously reported a successive diurnal change and a periodical diurnal rhythm
in the concentration of B group vitamins having an inverse correlation to the phytoplankton population in the waters of the southern basin of Lake Biwa (Kurata A. et al., 1982).
However, it is necessary to clarify the short term continual fluctuation in the concentration of B group vitamins in an in situ closed system, in order to more clearly elucidate the
interrelationship of the autochthonous vitamin production by microorganisms, and the
consumption by phytoplankton requiring these vitamins, without allochthonous vitamin
supply and water turbulence. Few reports have been published concerning the successive
diurnal changes, and the continual fluctuations in the concentration of B group vitamins
169