Sang-Buem Cho

Investigation on antibacterial and antioxidant activities, phenolic and flavonoid contents of some thai edible plants as an alternative for antibiotics.

This study was aimed to examine the antibacterial and antioxidative properties of seven edible plants from Thailand to develop alternative antibiotics as feed additives. The plants include Citrus aurantifolia Swingle (Lime) fruits and its leaves, Sesbania grandiflora L. (Agati sesbania) leaves, Piper sarmentosum Roxb (Wild betal) leaves, Curcuma domestica Valeton (Turmeric) roots, Morinda citrifolia L. (Beach mulberry) leaves, Cassia siamea britt (Siamea cassia) leaves, and Cocos nucifera L. (Coconut) peels. The plants were extracted by methanol, n-hexane, chloroform, ethyl acetate, butanol and water. Antibacterial activities with minimum inhibitory concentration (MIC) were determined by agar diffusion assay against Escherichia coli, Burkholderia sp., Haemopilus somnus, Haemopilus parasuis, and Clostridium perfringens that were considered pathogenic strains in livestock infection. Methanol extracts of C. aurantifolia Swingle fruits and leaves showed the broadest spectrum of antibacterial activities except for C. perfringens. Butanol extract of S. grandiflora L. leaves showed the strongest activity against Burkholderia sp. with MIC, 135 μg/mL. P. sarmentosum Roxb leaves showed antibacterial activities against E. coli, Burkholderia sp. and H. parasuis. Ethyl acetate and water extracts from C. domesitca Valeton roots showed MIC of 306 μg/mL and 183 μg/mL, respectively against only C. perfringens. Antioxidative activity was determined by 2-diphenyl-2-picryl hydrazyl photometric assay. The methanol extracts of C. aurantifolia Swingle fruits and P. sarmentosum Roxb leaves showed the highest antioxidant activity among all the extracts with 3.46 mg/mL and 2.70 mg/mL effective concentration 50% (EC50) values, respectively. Total contents of phenolics and flavonoids were measured from the plant extracts. Methanol extracts of S. grandiflora L. and chloroform extracts of C. domestica Valeton were found to have the highest amount of total phenolics, 41.7 and 47.8 μg/mL, respectively. Flavonoid content of methanol extracts in S. grandiflora L. T was 22.5 μg/mL and the highest among plant extracts tested. These results indicated that C. aurantifolia Swingle, S. grandiflora L., P. sarmentosum Roxb, and C. domestica Valeton have antibacterial and antioxidant activities and can be used as alternative antibiotics or potential feed additives for the control of animal pathogenic bacteria.

Neuroprotective effects of a sesquiterpene lactone and flavanones from Paulownia tomentosa Steud. against glutamate‐induced neurotoxicity in primary cultured rat cortical cells

The neuroprotective effects of Paulownia tomentosa against glutamate‐induced neurotoxicity were studied in primary cultured rat cortical cells. It was found that the aqueous extract of this medicinal plant significantly attenuated glutamate‐induced toxicity. In order to clarify the mechanism(s) underlying this neuroprotective effect, the active fractions and components were isolated and identified. Five compounds were isolated as the methanol extracts from air‐dried flowers of P. tomentosa. Isoatriplicolide tiglate exhibited significant neuroprotective activity against glutamate‐induced toxicity at concentrations ranging from 1 µm to 10 µm, and exhibited cell viability of approximately 43–78%. Therefore, the neuroprotective effect of P. tomentosa might be due to the inhibition of glutamate‐induced toxicity by the sesquiterpene lactone derivative it contains. Copyright

Anti-complement activity of isolated compounds from the roots of Clerodendrum bungei Steud.

To determine the anti‐complement activity of natural diterpenes, chromatographic separation of the acetone‐soluble fraction from the roots of Clerodendrum bungei (Verbenaceae) led to the isolation of five diterpenoids. An acetone‐soluble extract of the roots of C. bungei exhibited significant anti‐complement activity on the classical pathway complement system, which was expressed as total hemolytic activity. Five compounds isolated from the roots of C. bungei, namely 12‐O‐β‐d‐glucopyranosyl‐3,11,16‐trihydroxyabieta‐8,11,13‐triene (1), 3,12‐O‐β‐d‐diglucopyranosyl‐11,16‐dihydroxyabieta‐8,11,13‐triene (2), ajugaside A (3), uncinatone (4) and 19‐hydroxyteuvincenone F (5). Compounds 1, 2, 3, 4 and 5 showed inhibitory activity against complement system with 50% inhibitory concentrations (IC50) values of 24 µm, 138 µm, 116 µm, 87 µm and 232 µm. Among the compounds tested, 1 showed the most potent anti‐complement activity (IC50, 24 µm). Copyright

Retracted: Composition and immunotoxicity activity of essential oils from leaves of Zingiber officinale Roscoe against Aedes aegypti L

RETRACTION

Characteristics of Chinese chives (Allium tuberosum) fermented by Leuconostoc mesenteroides

This study was conducted to investigate the characteristics of bioactive compounds in Chinese chives juice (FC) fermented with Leuconostoc mesenteroides SK1962, a lactic acid bacteria isolated from Kim-chi. L. mesenteroides SK1962 only (LO) was used as comparison. The pH of FC gradually decreased from 6.21 to 4.23 during the 48-h incubation period, which was similar to that of LO. The growth of L. mesenteroides SK1962 in FC was higher compared with that in LO for various incubation times, with the exception of the 8-h incubation. Total polyphenol and flavonoid contents in FC were higher as compared with those in LO during incubation, leading to increased antioxidant activity in FC at different incubation times. Moreover, FC was more effective than LO in reduction of superoxide free radical production in primary bovine mammary alveolar cells. In addition, FC demonstrated antibacterial properties against pathogenic bacteria such as Listeria monocytogenes, Pantoea agglomerans, Haemophilus parasuis, Salmonella gallinarum, Escherichia coli O157, and Burkholderia. sp. Although LO also showed antibacterial effects against the above-mentioned pathogenic bacteria, its antibacterial activities were generally lower compared with those of FC. The results show that the antioxidant and antibacterial activities in Chinese chives was induced by fermentation with L. mesenteroides SK 1962. In conclusion, fermentation may lead to an increase in bioactive compounds including total polyphenol and flavonoid.

RETRACTED: Immunotoxicity activity of sesquiterpenoids from black galingale (Kaempferia parviflora Wall. Ex. Baker) against Aedes aegypti L.

RETRACTED

Cell Growth and Antioxidant Activity on Onion Juice Fermentation by Using Lactobacillus plantarum as Animal Probiotics

This study was conducted to establish the optimal medium condition for the animal probiotic Lactobacillus plantarum by using onion juice. Cell yield and antioxidant activity increased in proportion to high additive levels of onion juice in medium. Onion juice, sucrose and yeast extract were selected as media ingredient factors and the effects of their mixed ratio in medium were evaluated. The full factorial design consisted of 24 experimental runs and was employed to estimate the main effects of the factors and their interactions. Significant positive effects on cell yield and antioxidant activity was shown with yeast extract and onion juice, respectively. Significant interaction was found only between sucrose and yeast extract in antioxidant activity. Finally, we selected an optimal medium that was composed of (g/l) onion juice, 600; sucrose, 15; yeast extract, 5. The efficiency of this optimum medium was estimated by using a 5 l jar fermenter. As a result, the maximum cell yield was (CFU/ml) at 12 hr. Cell yield at the end of incubation (20 hr) was (CFU/ml) and it was very similar with the predicted value, (CFU/ml). Antioxidant activity of culture was maintained at about 60~65% during all incubation time, resulting in a higher-than-predicted activity of 47.1%.

Investigation of Dietary Lysophospholipid (Lipidol TM ) to Improve Nutrients Availability of Diet with In Vitro Rumen Microbial Fermentation Test

This study was conducted to investigate the effect of biological membrane transfer modifier, lysophospholipd (LPLs) on the parameters from in vitro rumen simulated fermentation. Commercially available LPLs product (Lipidol) was supplemented into experimental diets which consisted of orchard grass and concentrate diet (60:40) in different levels (0.1%, 0.3% and 0.5%). Then in vitro rumen simulated fermentation was performed. Although, a declining trend of pH was found in treatments, all pH values were detected in a range relevant to normal rumen fermentation. Gas production, ammonia nitrogen and total VFA production were greatly influenced by the supplementation of LPLs. All parameters were increased along with increased levels of LPLs in diet. As a result, 0.1% of Lipidol is recommended based on the determined in vitro rumen fermentative parameters in this study.

Protective effects of methoxyflavone derivatives from black galingale against glutamate induced neurotoxicity in primary cultured rat cortical cells.

To examine the neuroprotective effects of black galingale, its protection was tested against glutamate‐induced neurotoxicity in primary cortical cultured neurons. It was found that an aqueous extract of this medicinal plant exhibited significant protection against glutamate‐induced toxicity in primary cultured rat cortical cells. In order to clarify the neuroprotective mechanism(s) of this observed effect, isolation was performed to seek and identify active fractions and components. By such fractionation, bioactive methoxyflavone derivatives were isolated from the methanol extracts from the air‐dried rhizomes of black galingale. 5‐Hydroxy‐3,7,3′,4′‐tetramethoxyflavone exhibited significant neuroprotective activities against glutamate‐induced toxicity, exhibiting cell viability of about 60–70%, at concentrations ranging from 0.1 μm to 10 μm. Therefore, the neuroprotective effect of black galingale might be due to the inhibition of glutamate‐induced toxicity by the methoxyflavone derivatives it contains. Copyright

Contamination Analysis of Heavy Metals in Commercial Feed for the Production of Safe-Animal Products

The safety of animal feed was evaluated by analyzing the levels of heavy metals (Pb, Cr, Cd, As, Se and Ag) in cattle, swine, and poultry feeds and the levels of Cu, Zn and P in swine feed. Feeds used in the analysis were produced in Korea from 2004 through the first half of 2007. The results of the study revealed that, with the exception of Cd, the concentration of heavy metals were much lower than the Minimum Regulation Levels (MRLs). However, the Cd concentration exceeded the MRL in 1 of 987 swine feed samples in 2005, as well as in 4 of 1,239 swine feed samples and 1 of 778 poultry feed samples in 2006. The levels of Cu, Zn and P in swine feed were compared with the swine breeding standard. The results of this analysis revealed that the Cu concentrations in the samples exceeded the MRL for growing pigs by 0.97%, and that for finishing and breeding pigs by 9.9%. In addition, the Cu levels (80.98 ppm for piglet, 44.82 ppm for growing pigs, 19 ppm for finishing and breeding pigs) in swine feed showed higher levels compared to 3.5-6.0 ppm, which is the Cu requirement for swine. Furthermore, the results of the Zn analysis revealed that the samples exceeded the MRL for piglets, growing pigs, and finishing and breeding pigs by 5.7%, 7.7%, and 9.3%, respectively. Finally, the average concentration of P in swine feed was 0.74%, which is almost the same as the phosphate requirement for swine.