背景:婴儿肠道菌群产生的肠道气体和粪便短链脂肪酸(SCFA)可能对其健康产生重大影响。但是有关早产儿肠道气体的成分和体积以及SCFA谱的信息很少.目的:本研究研究了早产儿肠道菌群在生命的前4周内体外产生的肠道气体成分和体积以及SCFA谱的变化。方法:在五个时间点(3天内,1周,2周,3周,和4周)来自19名在上海市儿童医院新生儿重症监护病房(NICU)住院的早产儿,上海交通大学2020年5月至7月。这些样品最初接种到含有乳糖(LAT)的四种不同培养基中,低聚果糖(FOS),2'-岩藻糖基乳糖(FL-2),和低聚半乳糖(GOS),然后在厌氧条件下在37.8°C模拟大肠的条件下发酵24小时。总肠道气体的体积和单个二氧化碳(CO2)的浓度,氢气(H2),甲烷(CH4),和硫化氢(H2S)通过气体分析仪测量。总SCFA的浓度,单独的乙酸,丙酸,丁酸,异丁酸,戊酸,和戊酸通过气相色谱法(GC)测量。结果:肠道气体的总体积(在含LAT的培养基中为0.01至1.64ml;GOS为0-1.42ml;FOS为0-0.91ml;FL-2为0-0.44ml)以及CO2,H2,H2S的浓度,所有6种粪便SCFA随年龄增长而增加(p趋势<0.05)。其中,二氧化碳通常是主要的肠道气体,乙酸通常是主要的SCFA。按出生体重分层时(<1,500和≥1,500克),性别,和交付模式,与体重<1,500g的婴儿相比,体重≥1,500g的婴儿的CO2浓度更为明显(p趋势<0.05).结论:我们的发现表明,在生命的前4周内,早产儿肠道菌群在体外产生的肠道气体和SCFA随年龄增加。
Background: The production of intestinal gases and fecal short-chain fatty acids (SCFAs) by infant gut microbiota may have a significant impact on their health, but information about the composition and volume of intestinal gases and SCFA profiles in preterm infants is scarce. Objective: This study examined the change of the composition and volume of intestinal gases and SCFA profiles produced by preterm infant gut microbiota in vitro during the first 4 weeks of life. Methods: Fecal samples were obtained at five time points (within 3 days, 1 week, 2 weeks, 3 weeks, and 4 weeks) from 19 preterm infants hospitalized in the neonatal intensive care unit (NICU) of Shanghai Children\'s Hospital, Shanghai Jiao Tong University between May and July 2020. These samples were initially inoculated into four different media containing lactose (LAT), fructooligosaccharide (FOS), 2\'-fucosyllactose (FL-2), and galactooligosaccharide (GOS) and thereafter fermented for 24 h under conditions mimicking those of the large intestine at 37.8°C under anaerobic conditions. The volume of total intestinal gases and the concentrations of individual carbon dioxide (CO2), hydrogen (H2), methane (CH4), and hydrogen sulfide (H2S) were measured by a gas analyzer. The concentrations of total SCFAs, individual acetic acid, propanoic acid, butyric acid, isobutyric acid, pentanoic acid, and valeric acid were measured by gas chromatography (GC). Results: The total volume of intestinal gases (ranging from 0.01 to 1.64 ml in medium with LAT; 0-1.42 ml with GOS; 0-0.91 ml with FOS; and 0-0.44 ml with FL-2) and the concentrations of CO2, H2, H2S, and all six fecal SCFAs increased with age (p-trends < 0.05). Among them, CO2 was usually the predominant intestinal gas, and acetic acid was usually the predominant SCFA. When stratified by birth weight (<1,500 and ≥1,500 g), gender, and delivery mode, the concentration of CO2 was more pronounced among infants whose weight was ≥1,500 g than among those whose weight was <1,500 g (p-trends < 0.05). Conclusions: Our findings suggested that the intestinal gases and SCFAs produced by preterm infant gut microbiota in vitro increased with age during the first 4 weeks of life.