Chung-Yi Wang

Probiotic properties of Lactobacillus strains isolated from the feces of breast-fed infants and Taiwanese pickled cabbage.

This study assessed potential probiotic Lactobacillus strains isolated from the feces of breast-fed infants and from Taiwanese pickled cabbage for their possible use in probiotic fermented foods by evaluating their (i) in vitro adhesive ability, resistance to biotic stress, resistance to pathogenic bacteria, and production of β-galactosidase; (ii) milk technological properties; and (iii) in vivo adhesive ability, intestinal survival and microbial changes during and after treatment. Five Lactobacillus isolates identified as Lactobacillus reuteri F03, Lactobacillus paracasei F08, Lactobacillus rhamnosus F14, Lactobacillus plantarum C06, and Lactobacillus acidophilus C11 that showed resistance to gastric juice and bile salts were selected for further evaluation of their probiotic properties. All the strains demonstrated the ability to adhere to Caco-2 cells, particularly, strain L. plantarum C06 and L. reuteri F03 showed satisfactory abilities, which were similar to that of the reference strain L. rhamnosus GG. The strains L. paracasei F08 and L. acidophilus C11 had the highest β-galactosidase activity. Most of the strains were resistant to aminoglycosides and vancomycin but sensitive to ampicillin, erythromycin, and penicillin. All the 5 strains elicited antibacterial activity against both Gram-positive (Bacillus cereus, Listeria monocytogenes and Staphylococcus aureus) and -negative (Escherichia coli and Salmonella enterica) pathogens. Moreover, the strains L. reuteri F03, L. paracasei F08, and L. plantarum C06 could grow rapidly in milk without nutrient supplementation and reached 10⁸ cfu/mL after 24 h of fermentation at 37 °C. The viable cell counts of the 3 strains remained above 10⁷ cfu/mL after 21 d of storage at 4 °C. In the animal feeding trial, the number of intestinal lactobacilli increased significantly after administration of milk fermented with the 3 strains, and the counts of fecal coliforms and Clostridium perfringens were markedly reduced. Lactobacillus strains could also survive in the ileal intestinal tissue of the treated rats. Technologically interesting Lactobacillus isolates may be used in the future as probiotic starter cultures for manufacturing novel fermented foods.

Lactic acid bacterial fermentation on the production of functional antioxidant herbal Anoectochilus formosanus Hayata

This study evaluated a novel use of the traditional Asian herb Anoectochilus formosanus. This plant is a traditional food item, generally used for the treatment of liver disorder, hepatitis, hypertension, diabetes, cardiovascular disorder, etc. In this study, the root, stem, and leaf of A. formosanus were used as substrates for lactic fermentation. The fermentation products were analyzed for their total antioxidant activity, reducing power, and scavenging effect on superoxide anion radicals and hydrogen peroxide. The pH of the fermentation medium reached its lowest value, 3.5, at the 35th hour of fermentation. Antioxidant activity of A. formosanus was found to be 61-78%. Lactobacillus longum-led fermentation exhibited the greatest reducing power with an average of 0.3. The products of fermentations utilizing the three plant parts as substrates exhibited a similar scavenging activity (27-30%) on free radicals. This study may suggest a novel use of lactic-fermenting A. formosanus in the production of functional food.

Antioxidant properties of certain cereals as affected by food-grade bacteria fermentation

The effects of fermentation by 2 food-grade bacteria (Bacillus subtilis and Lactobacillus plantarum) on antioxidant activities and the contents of phenolics and flavonoids in 4 cereals (specifically adlay, chestnut, lotus seed, and walnut) were determined and compared with those of their non-fermented counterparts. Results showed that antioxidant properties observed in the fermented and non-fermented cereals may vary with fermented starters. Fermentation was observed to increase the phenolic and flavonoid contents of the extracts. The effects on Bacillus-fermented cereals were stronger than on Lactobacillus-fermented cereals. In IC50 values (mg/mL) of extracts, the extracts of fermented cereal showed a stronger DPPH radical scavenging and ferric-reducing activities. Fermentation did not significantly alter the Fe(2+)-chelating activity in the extracts of chestnuts and lotus seeds. All cereals were shown significantly inhibited the production of LPS-induced intracellular reactive oxygen species (ROS) without creating obvious cytotoxic effects in the macrophage cells. These results suggest that the fermentation process enables cereal-based foods with enhanced antioxidant capacities to contribute to health and nutritional improvements in consumers.

Probiotic potential of noni juice fermented with lactic acid bacteria and bifidobacteria

The present study assesses the feasibility of noni as a raw substrate for the production of probiotic noni juice by lactic acid bacteria (Lactobacilluscasei and Lactobacillus plantarum) and bifidobacteria (Bifidobacteriumlongum). Changes in pH, acidity, sugar content, cell survival and antioxidant properties during fermentation were monitored. All tested strains grew well on noni juice, reaching nearly 109 colony-forming units/ml after 48 h fermentation. L.casei produced less lactic acid than B.longum and L. plantarum. After 4 weeks of cold storage at 4°C, B.longum and L. plantarum survived under low-pH conditions in fermented noni juice. In contrast, L.casei exhibited no cell viability after 3 weeks. Moreover, noni juice fermented with B.longum had a high antioxidant capacity that did not differ significantly (P <0.05) from that of lactic acid bacteria. Finally, we found that B.longum and L. plantarum are optimal probiotics for fermentation with noni juice.

Virgibacillus chiguensis sp. nov., a novel halophilic bacterium isolated from Chigu, a previously commercial saltern located in southern Taiwan.

A Gram-positive, motile, endospore-forming, irregular rod-shaped (0.7-0.9 x 2.5-5.0 microm), halophilic bacterial strain, NTU-101(T), was isolated from Chigu saltern in southern Taiwan, previously used as a salt production field. The isolate was characterized taxonomically based on biochemical and molecular approaches. It grows optimally at 40 degrees C and in the presence of 5-10 % NaCl. Strain NTU-101(T) has cell-wall peptidoglycan based on meso-diaminopimelic acid and MK-7 as the predominant menaquinone. Major polar lipids are phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. Anteiso-C(15 : 0), iso-C(15 : 0) and anteiso-C(17 : 0) are the major fatty acids. The DNA G+C content was 37.3 mol%. Phylogenetic analyses based on 16S rRNA gene sequences showed its affiliation to the genus Virgibacillus. DNA-DNA relatedness values between strain NTU-101(T) and Virgibacillus dokdonensis and Virgibacillus pantothenticus were 17.5 and 21.5 %, respectively. Based on the phenotypic and phylogenetic properties, strain NTU-101(T) (=BCRC 17637(T)=CGMCC 1.6496(T)) was classified as a novel strain of Virgibacillus species, for which the name Virgibacillus chiguensis sp. nov. is proposed.

Free radical-scavenging and tyrosinase-inhibiting activities of extracts from sorghum distillery residue.

This study evaluated the potential free radical-scavenging and tyrosinase-inhibiting activities of extracts from sorghum distillery residue (SDR). The results demonstrated that methanol was a more efficient solvent for extracting the active components of SDR, and methanol extracts showed the highest radical-scavenging and tyrosinase-inhibiting activities.

Lactic fermentation and antioxidant activity of Zingiberaceae plants in Taiwan

The present study evaluated functional properties of lactic-fermented ginger products. Three Zingiberaceae species were used as the substrate for fermentation using three lactic acid bacteria. The fermentation process ended 35–40 h after inoculation and reached a pH value of 3.5–4.0. Total antioxidant performances were 68–75%, and were best observed using Bifidobacteriumlongum as the starter in three ginger samples. DPPH scavenging was on average 70%, with free radical anion scavenging and peroxide removal effects of 30.6% and 43.7%, respectively. The product acceptance survey showed that the 100% fermented juice without a mixture with non-fermented ginger juice obtained the highest score in overall performance. The lactic-fermented Vanoverberghia and Hedychium ginger species retained an antioxidant activity and DPPH scavenging activity of on average 70%. This study may suggest a new way of ginger food processing with high functionality. Also, it may help to popularize the growing and processing of endemic ginger plants in Taiwan.

Marinobacter szutsaonensis sp. nov., isolated from a solar saltern

A Gram-negative, aerobic, non-spore-forming, halophilic bacterial strain, NTU-104(T), was isolated from the Szutsao saltern in southern Taiwan, which was previously used as salt production field. The novel isolate grew optimally at 35-40 degrees C, at pH 7.5-8.0 and in the presence of 5 % (w/v) NaCl. The major fatty acids were C(16 : 0), C(18 : 1)omega9c, C(16 : 1)omega9c, C(12 : 0) 3-OH and C(12 : 0). The predominant quinone was Q-9. Phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine were the predominant polar lipids. The DNA G+C content was 56.5 mol%. Phylogenetic analyses based on 16S rRNA gene sequences revealed the affiliation of the novel isolate to the genus Marinobacter. DNA-DNA hybridization results between strain NTU-104(T) and the type strains of the most closely related species, Marinobacter pelagius and Marinobacter koreensis, were 36.4 % and 33.2 %, respectively. On the basis of phenotypic, phylogenetic and genetic analyses, strain NTU-104(T) is considered to represent a novel species of the genus Marinobacter. The name Marinobacter szutsaonensis sp. nov. is proposed, with strain NTU-104(T) (=BCRC 17809(T)=CGMCC 1.7011(T)=JCM 15751(T)) as the type strain.

Halomonas beimenensis sp. nov., isolated from an abandoned saltern

A Gram-staining negative, motile, non-spore-forming, short rod-shaped (0.8-1.5 × 1.5-2.0 µm), halophilic bacterium, designated strain NTU-107(T), was isolated from brine samples collected from the abandoned Beimen saltern in southern Taiwan. The novel strain grew with 0-15% (w/v) NaCl (optimum between 5% and 10%), at 15-55 °C (optimum 40 °C) and at pH 5.5-9.5 (optimum pH 7.5). The major cellular fatty acids were C(18:1)ω7c, C(16:0) and C(19:0 )cyclo ω8c, the genomic DNA G+C content was 66.5 mol%, and the predominant ubiquinone was Q-9. The major polar lipids included phosphatidylglycerol, diphosphatidylglycerol and phosphatidylethanolamine. In a phylogenetic analysis based on 16S rRNA gene sequences, strain NTU-107(T) clustered with members of the genus Halomonas. In hybridization experiments, however, the levels of DNA-DNA relatedness between strain NTU-107(T) and the type strains of its closest phylogenetic neighbours (Halomonas koreensis, H. organivorans and H. ventosae) were all found to be less than 40 %. Based on the phenotypic, chemotaxonomic and genetic data, strain NTU-107(T) represents a novel species within the genus Halomonas, for which the name Halomonas beimenensis sp. nov. is proposed. The type strain is NTU-107(T) ( = BCRC 17999(T) = KCTC 22876(T) = JCM 16084(T)).

Activity of cellulase from Thermoactinomycetes and Bacillus spp. isolated from Brassica waste compost

Residuos vegetais apresentam alta concentracao de celulose, que e um material orgânico ideal para preparacao de composto. Cinco linhagens de termofilos foram isoladas de residuos processados de Brassica e a atividade hidrolitica em varios substratos contendo celulose e seus padroes de temperatura foram determinados. O sequenciamento de rRNA 16S permitiu a identificacao dessas isolados como Thermoactinomyces e Bacillus spp. A atividade maxima de celulase foi determinada como de 2,3 U mL-1 de enzima. O uso dessas linhagens em residuos de Brassica rapa resultou em um aumento total do conteudo de nitrogenio. TA-3, uma linhagem de Thermoactinomycetes sp., apresentou melhor desempenho entre os inoculantes, aumentando o conteudo de nitrogenio de 0,74 para 0,91%, e diminuindo o conteudo de carbono de 15,4 para 12,2%, mostrando sua alta eficiencia e bioatividade durante a compostagem.