This study aimed to select Bacillus spp. for surfactin production by solid-state fermentation and to investigate the physiochemical characterizations of the fermented product (FP) and its effect on growth performance, carcass trait, intestinal morphology, and clinical blood biochemistry of broilers. Accordingly, the correlations between the functional components of FP and the growth performance of broilers are elucidated. Four hundred eighty 1-day-old Ross 308 broiler chicks were randomly assigned to dietary supplementation of 2.5% fish meal, 2.5% unfermented product, or 2.5% FP produced by Bacillus subtilis LYS1 (LYS1), Bacillus amyloliquefaciens Da16, B. subtilis Lo6 (Lo6), B. subtilis NSN7, B. subtilis subsp. natto N21, or B. subtilis N12. Each treatment had 6 replicates. The experimental period was 5 wk. Results showed that the Lo6 showed the highest protease activity among all fermented groups. The LYS1 showed the highest surfactin yields (10.69 mg/g) among all fermented groups (P < 0.05). The weight gain (WG), feed conversion ratio (FCR), and production efficiency factor (PEF) of LYS1 group were significantly better than unfermented group at 0 to 3 and 0 to 5-wk-old (P < 0.05). The Bacillus-like counts and surfactin content of FP were moderately correlated to WG (0.7 > r > 0.3), FCR (-0.3 > r > -0.7), and PEF (0.7 > r > 0.3) at 0 to 3 and 0 to 5-wk-old (P < 0.05). The protease activity of FP was moderately correlated to WG (0.7 > r > 0.3), FCR (-0.3 > r > -0.7), and PEF (0.7 > r > 0.3) at 0 to 3-wk-old (P < 0.05). The villus height to crypt depth ratio in duodenum and jejunum of fish meal group and LYS1 group were higher than unfermented group (P < 0.05). In conclusion, LYS1 shows the highest surfactin yields. Diets supplemented with 2.5% LYS1 FP can improve the growth performance and the development of intestinal villi in broilers. Moreover, this study proves that the surfactin content, Bacillus-like counts, and protease activity of FP show a correlation to the growth performance of broilers.

This study aimed to investigate the physiochemical characterizations of the fermented product (FP) produced by the high-yield surfactin strain Bacillus subtilis LYS1 (LYS1), as well as its effects on growth performance, carcass traits, intestinal morphology, tibial bone characteristics, and clinical blood biochemistry in broilers. Accordingly, the optimal supplementation of FP for improving growth performance, intestinal villi development, and tibial bone strength in broilers was elucidated using a broken-line quadratic (BLQ) ascending model. Three hundred and sixty 0-day-old Ross 308 broiler chicks, with equal numbers of both sexes, were randomly assigned to dietary supplementation of 2.5% fish meal or 0, 1, 1.5, 2, or 2.5% FP. Each treatment had six replicates, and the experimental period was 5 wk. The LYS1 count, surfactin content, and surfactin composition of the FP were 9.1 log CFU/g, 11.23 mg/g, and C₁₂ to C₁₈, respectively. The FP-supplemented groups improved feed intake, weight gain (WG), and production efficiency factor at 0 to 5 weeks old (p < 0.05) compared with the 0% group. The villus height/crypt depth (V/C) in the jejunum and ileum of the FP-supplemented groups was higher than in the 0% group (p < 0.05). The tibiotarsal index, Ca, and P in the tibia showed a linear effect with increased FP supplementation (p < 0.05). Moreover, the tibiotarsus weight/length index (TWLI) showed a quadratic effect with increased FP supplementation (p < 0.05). The optimal supplementation of FP for WG, V/C in the jejunum and ileum, and TWLI was 1.8, 1.9, and 1.6%, respectively. In conclusion, dietary supplementation with 1 to 2.5% LYS1 FP in broilers can improve their growth performance and the development of intestinal villi. Moreover, 1.9% is the optimal supplementation of LYS1 FP in the diet, based on the fitting results obtained with the BLQ model.

This is the first study to discuss the effects of dark septate endophytes (DSE) on the growth promotion and berberine concentration in Mahonia oiwakensis, whose extract (MOE) has been suggested to have potential therapeutic effects against human lung cancer. First, as per phylogenetic analysis, the strains were divided into four groups: CkDB2, CkDB5, MoAL2 and MoAL5. All of these were DSEs, which could form microsclerotia in M. oiwakensis. The growth response experiment revealed that inoculation of the plant with MoAL5 and CkDB5 promoted an increase in the total fresh weight of the seedlings. Chemical composition analysis showed that seedlings inoculated with CkDB5 had the highest berberine concentration. These results showed that some DSEs have the ability to promote growth and induce phytochemical responses in the host plant.