Plant Foods for Human Nutrition 61: 87–89, 2006. c  2006 Springer Science+Business Media, Inc. DOI: 10.1007/s11130-006-0019-3 87 Biochemical Composition and Indigestible Oligosaccharides in Phaseolus vulgaris L. Seeds L ´ ILIAN DA SILVA FIALHO, VAL ´ ERIA MONTEZE GUIMAR ˜ AES, EVERALDO GONC ¸ALVES DE BARROS, MAURILIO ALVES MOREIRA, LUIZ ANT ˆ ONIO DOS SANTOS DIAS, MARIA GORETI DE ALMEIDA OLIVEIRA, IN ˆ ES CHAMEL JOS ´ E & SEBASTI ˜ AO TAVARES DEREZENDE ∗ Universidade Federal de Vic ¸osa – BIOAGRO, CEP 36570-000, Vic ¸osa, MG Brasil ( ∗ author for correspondence; e-mail: srezende@ufv.br) Published online: 20 June 2006 Abstract. Common beans have a high nutritional value, but contain galac- tooligosaccharides (GO), which cause flatulence and intestinal discom- fort in humans. The biochemical composition of ten bean cultivars was determined to select those of high protein and low GO contents. The cultivars varied in carbohydrate (47.02–60.17%), GO (3.12 – 5.71%), protein (22.17–33.50%), lipid (1.13–1.81%), moisture (11.42–12.93%) and ash contents (4.08–5.61%). ‘Mexico 222’ presented the highest α- galactosidase activity. Protein and GO contents were positively correlated. ‘Perry Marrow’ combined high protein and low GO concentrations, in- dicating it can be used in improvement programs aiming at high-quality cultivars for human consumption. Key words: Phaseolus vulgaris, Galactooligosaccharides, α-galacto- sidase, Flatulence, Protein Introduction Common bean (Phaseolus vulgaris L.) is an important source of protein, carbohydrates, fibers, vitamins, unsat- urated fatty acids, and micronutrients [1]. Brazil is the first world producer of the species Phaseolus vulgaris [2]. Bean grains contain 20–35% protein and 50–60% carbo- hydrates, but present antinutritional factors such galac- tooligosaccharides (GO), mainly raffinose, stachyose and verbascose [3]. The GO are heat resistant and remain in the end product [4]. Due to the absence of α-galactosidase (EC 3.2.1.22) in the intestinal tract of human, the GO are accumulated and fermented, producing a large amount of gases. The GO are considered inducers of gastrointestinal disorders, diarrhea and flatulence, inhibiting nutrient uptake [5]. α-Galactosidases present in bean grains can be poten- tially used for several biotechnological applications, mainly in the food industry to hydrolyze the GO in soybean products [6, 7]. Several studies aimed at the selecting α- galactosidase sources in plants to be used in enzymatic processes. Here the biochemical composition and α-galactosidase activity of 10 bean cultivars were determined. These cul- tivars are used in the bean breeding program of BIOA- GRO/UFV, which aims to select cultivars with high protein and low GO contents to be used for human nutrition. Material and Methods Cultivars Rud´ a, P´ erola, Michelite, Cornell 49-242, TU, AB 136, Mexico 222 (Mesoamerican origin) and Kaboon, Perry Marrow, MDRK (Andean origin) were provided by the BIOAGRO/UFV bean breeding program. For a determina- tion of the moisture content, approximately 1 g of grain was dried at 105 ◦ C for 24 h. Total proteins (Kjeldahl method), lipid, carbohydrate and ash contents were determined as de- scribed by AOAC [8]. To determine α-galactosidase activ- ity, samples of 100 mg of ground grains were homogenized with 1.5 ml 100 mM sodium acetate buffer, pH 5.0. The enzyme extract was centrifuged at 16,100 × g for 7 min, at 4 ◦ C, and protein concentration [9] and α-galactosidase ac- tivity [7] were determined in the supernatant. One enzyme unit (U) was defined as the quantity of protein required to produce 1 μmol of ρ -nitrophenol (ρ NP) per min. GOs were extracted from 20 mg of grain powder as described by Guimar˜ aes et al. [6]. Aliquots of 20 μl were analyzed by HPLC, in a 10A Shimadzu Chromatograph, using re- fraction index detector, LC-NH 2 Supelcosil column (5 μm, 250 × 4.6 mm), at 35 ◦ C, and acetonitrile-water 70:30 (v/v) at a flow rate of 1.0 ml/min. All data were subjected to tests of normality. Means were compared by the Tukey test. Pearson’s correlation analyses were also performed. Results and Discussion The moisture contents in grains varied from 11.4 to 12.9%. This range is close to that observed by Shimelis and Rakshit [10]. Protein concentration in the grains varied from 22.17 to 33.50%, in agreement with values cited by Grupta [11]. The highest protein values (29.49–33.5%) were observed in cultivars Cornell 49-242, Perry Marrow, MDRK, and P´ erola. Lipid concentrations varied from 1.13 to 1.81%, comparable to those described by Costa et al. [12]. The ash contents varied from 4.08 to 5.61%. Total carbohydrate contents varied from 59.42 to 71.59%, as also determined by Rehman et al. [13]. GOs are considered antinutritional factors since they in- duce gastrointestinal disorders, flatulence and diarrhea [14]. The GO contents varied from 3.12 to 5.71%, while total