Abstract: The present invention comprises a method of producing .beta.-1,3-glucan wherein a microbe capable of producing .beta.-1,3-glucan is cultured in a medium containing as a nitrogen source an ammonium salt of an organic carboxylic acid the microbe can assimilate wherein the .beta.-1,3-glucan is produced and accumulated, and then harvesting. The .beta.-1,3-glucan production method of the present invention does not require addition of a pH regulator such as calcium carbonate or alkali ions, since the medium does not decrease in pH because a microbe capable of producing .beta.-1,3-glucan is cultured in a medium containing as a nitrogen source an ammonium salt of an organic carboxylic acid which the microbe can assimilate. For this reason, cultivation is not adversely affected, nor does any salt form in the medium, aspects which facilitate purification of said glucan, offering an industrially excellent production method. Moreover, the method of the present invention makes it feasible to produce .beta.

Abstract: Disclosed is a microorganism belonging to the genus Agrobacterium which is able to produce .beta.-1,3-glucan and is either deficient or defective in phosphoenolpyruvate carboxykinase activity. Preferred microorganisms are mutants of Agrobacterium sp. biovar I. Particularly preferred mutant strains are Agrobacterium sp. biovar I GA-27 (FERM BP-4350) and Agrobacterium sp. biovar I GA-33 (FERM BP-4351).

Abstract: A microorganism belonging to the Gram-positive cocci having not less than about 55 mol % of guanine plus cytosine content of DNA is cultivated in a medium. Trehalose is produced and extracellularly accumulated in the medium with a good yield. The present method, therefore, brings about a feasible method for the industrial production of trehalose. Preferably, the microorganism used is Deinococcus proteolyticus (IFO 15345), Deinococcus erythromyxa (IFO 15344), Deinococcus radiopugnans (IFO 15348), Micrococcus varians (FERM BP-4238 and IFO 3765), Micrococcus agilis (IFO 15323) or Microccus luteus (IFO 3067 and IFO 12708).

Abstract: In a fermentive production of polyglutamic acid and a salt thereof, the accumulation of polyglutamic acid can be markedly increased in a very simple manner by adding an alkaline earth metal ion to the medium in a concentration of not less than 0.05 mole per liter.

Abstract: A tasty yeast extract is obtained by heating an aqueous suspension of yeast at 55.degree. to 70.degree. C., allowing the yeast cells to autolyze at pH 8 to 10, and eliminating water insoluble matter from the suspension and recovering the yeast extract.

Abstract: L-Glutamic acid is produced in a high yield by cultivating an L-glutamic acid-producing microorganism which requires oleic acid but does not require biotin for growth in a culture medium containing an oleic acid compound and a biotin compound of no less than 100 .mu.g/liter as biotin, with carbohydrate and acetic acid as carbon sources being maintained in a weight ratio of about 80:20 through about 40:60.