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''Lactobacillus hilgardii'' (also known as ''Lacobacillus vermiforme'') is a species of bacterium found in wine, dairy products, and wine musts. Its morphology is consistent (on a cellular level) of rods that are 0.5–0.8 micrometres of both single short chains and long filament like structures. On a colony level, the bacteria appears glossy, round and white. For study, the bacteria requires malt agar and can ferment maltose, but often also requires yeast extract in order to ferment properly. To study ''L. hilgardii'' in liquid requires growing it in Elliker broth so it can show turbidity and gas formation. Grams strain of the bacteria are positive. ''L. hilgardii'' is considered a negative catalase (enzyme that decomposes hydrogen peroxide into oxygen and water) and creates lactic acid, ethanol/acetic acid, and carbon dioxide. Along with this it is capable of sometimes producing biogenic amines or histamine and ethyl carbamate, which causes health risks. Its role in the fermentation of wine is that it is impactful when spoiling high-alcohol dessert wines and can be used in malolactic fermentations (winemaking fermentation). ''Lactobacillus hilgardii'' is sensitive to SO2, both not sensitive and metabolized to sorbate. It is highly tolerant to acids and pH. It is tolerant of ethanol up to 20 vol%. ''Lactobacillus hilgardii'' hybridizes easily with ''Lactobacillus brevis'', a bacteria that it is very taxonomically close to. Prior to its specization ''L. hilgardii'' was believed to be ''L. brevis'', and as a result, the bacteria’s ability to hybridize raised doubts about the bacteria’s taxonomy. ''L. hilgardii'' grows in wine when it contains 1% autolysated yeast. It also grows in ethanol at 15–18%. The bacteria grow best between 30 and 35 degrees Celsius, and can grow at temperatures as low as 15 degrees Celsius. ==References== 〔 * * * * 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Lactobacillus hilgardii」の詳細全文を読む スポンサード リンク
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