Biohydrogen production is a cheap and clean way to obtain hydrogen gas. In subtropical countries such as Brazil the average temperatures of 27 °C can favor the hydrogen producing bacteria growth. A mixed culture was obtained from a subtropical sludge treating brewery wastewater and anaerobic batch reactors were fed with glucose, sucrose, fructose and xylose in low concentrations (2.0, 5.0 and 10.0 g L⁻¹) at 37 °C, initial pH 5.5 and headspace with N₂ (99%) to maintain the anaerobic conditions. The inoculum was a subtropical granulated sludge from UASB (Upflow Anaerobic Sludge Blanket) reactor treating brewery wastewater. The higher H₂ yields were obtained in reactors operated with 2 and 5 g L⁻¹ of fructose and they were 1.5 mol H₂ mol⁻¹ of fructose and 1.3 mol H₂ mol⁻¹ of sucrose, respectively. The volatile fatty acids (VFA) generated at the end of operation were, predominantly, butyric and acetic acid, indicating the favoring of the metabolic route of hydrogen generation by the consortium of anaerobic bacteria from the brewery wastewater. Biomolecular analyses revealed the predominance of hydrogen producing bacteria from Firmicutes phylum distributed in the families Streptococcaceae, Veillonellaceae and uncultured bacteria. These results confirm future applications of subtropical sludges with agroindustrial wastewaters containing low concentrations of sugars on hydrogen generation.

生物制氢是一种廉价，清洁的获取氢气的方法。在亚热带国家（如巴西），平均温度为27°C可以促进产氢细菌的生长。从亚热带污泥处理啤酒废水中获得混合培养物，并在37°C，初始pH 5.5和顶部空间向厌氧间歇反应器中加入低浓度（2.0、5.0和10.0 g L ^-1）的葡萄糖，蔗糖，果糖和木糖。用N ₂（99％）维持厌氧条件。接种物是来自UASB（上流厌氧污泥毯）反应器的亚热带颗粒污泥，用于处理啤酒废水。在使用2和5 g L ^-1果糖操作的反应器中获得了更高的H ₂收率，它们是1.5 mol H₂ 摩尔^-1的果糖和1.3摩尔H ₂ 摩尔^-1的蔗糖。在操作结束时产生的挥发性脂肪酸（VFA）主要是丁酸和乙酸，这表明来自啤酒废水的厌氧细菌财团有利于产氢的代谢途径。生物分子分析揭示了主要分布在链球菌科，绒藻科和未培养细菌科中的菲门菌产氢细菌的优势。这些结果证实了亚热带污泥在含有低浓度糖类的农用工业废水产生氢气方面的未来应用。