Determination of the Antimicrobial and Antioxidative Properties and Total Phenolics of Two “Endemic” Lamiaceae Species from Turkey: <Emphasis Type="Italic">Ballota rotundifolia</Emphasis> L. and <Emphasis Type="Italic">Teucrium chamaedrys</Emphasis> C. Koch

This study was designed to examine the in vitro antimicrobial and antioxidant activities and the amount of total phenolics of the methanol extracts of Ballota rotundifolia L. and Teucrium chamaedrys C. Koch. In the case of antimicrobial activity tests, polar sub-fractions of the methanol extracts of plant species exhibited weakest antimicrobial activity when compared with the non-polar ones. While, non-polar sub-fraction of B. rotundifolia showed moderate activity against A. lwoffii, C. perfringens and the yeasts, T. chamaedrys performed excellent activity pattern against all of the tested microorganisms. The sub-fractions were also screened for their possible antioxidant activities by two complementary tests, namely DPPH free radical-scavenging and β-carotene/linoleic acid assays. Non-polar extracts of the plant species remained inactive in both test systems. On the other hand polar extracts showed remarkable antioxidant activities. In DPPH system, free radical scavenging effect of T. chamaedrys was measured as 18.00 ± 1.42 μg.mg⁻¹. It is extremely important to point out that, polar sub-fraction of T. chamaedrys is found as effective as the positive control BHT. Non-polar sub-fraction of T. chamaedrys found to have the highest total phenolic amount (97.12 ± 1.28 μg/mg). Results obtained from this experiment confirm the relationship between the amount of phenolics and biological activities.     

Antioxidant,Antimicrobial and Genotoxicity Screening of Hydro-alcoholic Extracts of Five Serbian <Emphasis Type="Italic">Equisetum</Emphasis> Species

The hydro-alcoholic extracts of five Equisetum species, E. arvense L., E. sylvaticum L., E. fluviatile L., E. palustre L. and E. telmateia Ehrh., growing-wild in Serbia were evaluated for their genotoxicity, antimicrobial activity, antioxidant capacity and the results related to the total phenol content and HPLC flavonoid profiles. The total phenol content was 92–349 μmol expressed as equivalents of chlorogenic acid per g of dried plant material. Main identified compounds were kaempferol-, quercetin- glycosides and caffeic acid derivatives. E. telmateia extract showed the greatest antioxidant capacity. Almost all tested microorganisms demonstrated some degree of sensitivity to the examined extracts. All tested extracts at 62.5 μg/ml showed higher incidence of micronucleus formation than in the control sample. The obtained data allowed mutual comparison of examined species and their assessment as possible sources of antioxidants, antimicrobials and/or genotoxic substances.     

Antioxidant activity and phenolic content of chestnut (Castanea sativa) shell and eucalyptus (Eucalyptus globulus) bark extracts

Chestnut (Castanea sativa) shell and eucalyptus (Eucalyptus globulus) bark, waste products of the food and wood industries, respectively, were analysed as potential sources of antioxidant compounds. The extraction yield, the antioxidant activity and total phenols content of the extracts were greater in chestnut shell than in eucalyptus bark for most of the extraction conditions essayed. Extraction of chestnut shell with a 2.5% Na₂SO₃ aqueous solution led to the highest extraction yield, 25.6%, total phenols, 13.4 g gallic acid equivalent/100 g oven-dried shell, and FRAP antioxidant activity, 80.7 mmol ascorbic acid equivalent/100 g oven-dried shell. Extraction with methanol:water (50:50, v/v) provided the best results for eucalyptus bark. The antioxidant activity and the total phenols content of the extracts had a positive linear correlation. FTIR spectroscopy confirmed the higher content of phenolic compounds in chestnut shell extracts compared to eucalyptus bark extracts. Chestnut shell extracts were characterized by the presence of high molecular weight species whereas lower molecular weight species were predominant in eucalyptus bark extracts.     

<Emphasis Type="BoldItalic">In Vitro</Emphasis> Antioxidant and Anti-rhizopus Activities of Lamiaceae Herbal Extracts

Eighty-eight extracts of different polarity obtained from 18 Lamiaceae medicinal and aromatic plants were screened for their antioxidant and antifungal properties. A TLC analysis combined with two bioassays were used to detect these activities. In most cases the highest radical scavenger capacity was detected in methanolic and aqueous extracts and polyphenols may be responsible. The most interesting antioxidant activity was observed in polar extracts obtained from Lycopus europaeus, Melissa officinalis, Origanum vulgare subsp. virens and Lavandula latifolia. On the contrary, the best results for the antifungal test against Rhizopus stolonifer were produced by non-polar herbal extracts. Phlomis lychnitis, Salvia pratensis and Calamintha sylvatica caused the highest inhibition on Rhizopus growth.     

Identification and Quantification of Steroidal Alkaloids from Wild Tuber-Bearing <Emphasis Type="Italic">Solanum</Emphasis> Species by HPLC and LC-ESI-MS

Wild Solanum species are characterized by several types of glycoalkaloids (GAs), which are usually not found in commercial potato cultivars. These alkaloids serve as defence compounds against herbivores and microorganisms, especially fungi. In this study, the GA composition of tuber and leaf material of 17 wild Solanum species was analysed qualitatively by liquid chromatography-electrospray ionization-mass spectrometry (LC-ESI-MS) and quantitatively by high-performance liquid chromatography. The GAs identified were α-solanine, α-chaconine, β-chaconine, solasonine, solamargine, demissine, dehydrodemissine, α-tomatine, dehydrotomatine, commersonine, dehydrocommersonine, leptine I and leptine II. Most species accumulated the common potato GAs α-solanine and α-chaconine in tubers and solasonine and solamargine additionally in leaves. In some species, such as S. acaule ssp. acaule, S. demissum and S. polyadenium, substantial amounts of unusual alkaloids were detected. By using LC-ESI-MS, we detected several minor alkaloids such as dehydrogenated forms of α-tomatine, demissine and commersonine for the first time. Total GA content, expressed as the sum of the four main alkaloids α-solanine, α-chaconine, solamargine and solasonine differed from species to species. In general, GA contents in leaf tissue were higher and GA patterns were more complex than those of tubers.     

Phenolics,Sugars, Antimicrobial and Free-Radical-Scavenging Activities of <Emphasis Type="Italic">Melicoccus bijugatus</Emphasis> Jacq. Fruits from the Dominican Republic and Florida

Edible fruits of the native South American tree Melicoccus bijugatus Jacq. are consumed fresh or in traditional food, drink and medicinal preparations. Some therapeutic effects of these fruits may be due to phenolics and sugars. Aqueous acetone, methanol or ethanol tissue extracts of different cultivars or collections of M. bijugatus fruits from the Dominican Republic and Florida were analyzed for total phenolics and free radical scavenging activity by UV-vis spectroscopy, sugars by gas chromatography, and antimicrobial activity by the disc diffusion assay. Total phenolics and free radical scavenging activities ranked: seed coat > embryo > pulp extracts. Montgomery cultivar fruits had the highest total phenolics. For sugars: pulp > embryo and highest in Punta Cana fruit pulp. In all extracts: sucrose > glucose and fructose. Glucose:fructose ratios were 1:1 (pulp) and 0.2:1 (embryo). Pulp extracts had dose-response antibacterial activity and pulp and embryo extracts had antifungal activity against one yeast species. Phenolics and sugars were confirmed with thin-layer chromatography and nuclear magnetic resonance. Sugar-free pulp fractions containing phenolics had slightly more antimicrobial activity than H₂O-soluble pulp fractions with sugars. Results indicate M. bijugatus fruits contain phenolics, sugars and other H₂O-soluble compounds consistent with therapeutic uses. Electronic supplementary material  The online version of this article (doi:) contains supplementary material, which is available to authorized users.     

Antioxidant Activities of Four Edible Seaweeds from the Southern Coast of Thailand

The aqueous extracts of four marine algae, Caulerpa racemosa var. macrophysa, Gracilaria tenuistipitata var. tenuistipitata, Sargassum sp., and Ulva lactuca, from the coastal areas in Southern Thailand, were prepared by boiling dried seaweed powder in water for 3 h, and by autoclaving each sample at 120 °C for 3 h. They were then freeze-dried and evaluated for their antioxidant activities using DPPH (1, 1-diphenyl-2-picrylhydrazyl), hydroxyl radical (OH^•) and superoxide anion (O₂^•−) scavenging assays. Boiling extracts of the seaweeds, except C. racemosa, were found to have higher total phenolic contents (TPC) than those obtained from the autoclave method. The antioxidant results also showed that O₂^•− scavenging activity existed only in the boiling extracts of C. racemosa, G. tenuistipitata, and U. lactuca. In DPPH and OH^• assays, however, almost all the boiling extracts were less active than the autoclave ones. Among the four alga species, Sargassum sp. was the most active. Both extracts of this seaweed had the highest TPC and also displayed the strongest DPPH^• and OH^• inhibitory activities. A strong positive-correlation between the antioxidant potency and TPC of the autoclave extracts was found, while for the boiling extracts such relation was very weak. This result thus reflected that in addition to the phenolic compounds, there might be some other active components present in these extracts involved in the antioxidant activity.     

Antioxidant and Antimicrobial Activity of Zingiberaceae Plants in Taiwan

The rhizomes of the Zingiberaceae family are a vegetable widely used in many Asian countries, and their medicinal functions have been broadly discussed and accepted in many traditional recipes. In this study, 18 species of five genus of Zingiberaceae plants from Taiwan area were collected and analyzed for their functional properties. Methanolic extracts of the plants were analyzed for their total phenol compounds, α,α-diphenyl-β-picrylhydrazyl (DPPH) scavenging activity, and reducing power. Antimicrobial activity of these samples was also determined. The results showed that the total phenol compounds of the Alpinia genus averaged 17, 30 mg/g for Curcumas, and the highest, 36.5 mg/g for Vanoverberghia sasakiana. Antioxidant performances were best observed in Vanoverberghia and Hedychium, both 89%, and DPPH scavenging activity followed similar trends. Particularly, Zingiber oligophyllum, considered as a traditional medicinal plant used in Taiwan exhibited low DPPH scavenging activity and reducing power. Most Zingiberaceae plant extracts exhibited antimicrobial activity against all tested food microorganisms. Hedychium and Vanoverberghia, did not show antimicrobial activities on Escherichia coli and Vibrio parahaemolyticus. This study is a positive demonstration of the utility of screening Taiwan’s endemic Zingiberaceous plants for their food and medicinal uses.     

Antioxidative and Anticancer Activity of Extracts of Cherry (<Emphasis Type="Italic">Prunus serrulata</Emphasis> var. <Emphasis Type="Italic">spontanea</Emphasis>) Blossoms

Organic solvent (methanol, ethanol, and acetone) extracts and water extracts of cherry (Prunus serrulata var. spontanea) blossoms were prepared, and antioxidant activities of the extracts were evaluated. Methanolic CBE (100 μg/ml) showed the highest total phenol content (104.30 μM), radical scavenging activity (34.2%), and reducing power (0.391). The effect of CBE on DNA damage induced by H₂O₂ in human leukocytes was evaluated by Comet assay. All CBE was a potent dose dependent inhibitor of DNA damage induced by 200 μM of H₂O₂, methanolic CBE showed the most strong inhibition activity. The methanolic CBE of 500 μg/ml showed 38.8% inhibition against growth of human colon cancer cell line HT-29. These results indicated that cherry blossoms could provide valuable bioactive materials.     

Production of phytoalexins, glycoalkaloids and phenolics in leaves and tubers of potato cultivars with different degrees of field resistance after infection withPhytophthora infestans

Summary The kinetics of accumulation of phytoalexins, glycoalkaloids and phenolics was studied in two potato cultivars differing in their degrees of field resistance when infected withPhytophthora infestans. Tuber slices and leaves of cvs Pampeana INTA (high degree of field resistance, free of R genes) and Bintje (susceptible) were infected with race C (complex race 1, 3, 5, 7, 11) ofPhytophthora infestans. Phytoalexins and phenolics accumulated in tuber and leaf tissues which had been inoculated. The levels of these compounds in the susceptible cv. Bintje were relatively low and similar to those found before inoculation. Leaves of cv. Pampeana INTA had a very high glycoalkaloid content, suggesting that glycoalkaloids may play a role in protection of leaves against the fungus. However, we could find no correlation between resistance and glycoalkaloid content of tubers. Our results suggest a major role of phytoalexins, phenolics and glycoalkaloids in the complex mechanisms of field resistance.     

Antimicrobial and cytotoxic assessment of marine cyanobacteria - Synechocystis and Synechococcus

Aqueous extracts and organic solvent extracts of isolated marine cyanobacteria strains were tested for antimicrobial activity against a fungus, Gram-positive and Gram-negative bacteria and for cytotoxic activity against primary rat hepatocytes and HL-60 cells. Antimicrobial activity was based on the agar diffusion assay. Cytotoxic activity was measured by apoptotic cell death scored by cell surface evaluation and nuclear morphology. A high percentage of apoptotic cells were observed for HL-60 cells when treated with cyanobacterial organic extracts. Slight apoptotic effects were observed in primary rat hepatocytes when exposed to aqueous cyanobacterial extracts. Nine cyanobacteria strains were found to have antibiotic activity against two Gram-positive bacteria, Clavibacter michiganensis subsp. insidiosum and Cellulomonas uda. No inhibitory effects were found against the fungus Candida albicans and Gram-negative bacteria. Marine Synechocystis and Synechococcus extracts induce apoptosis in eukaryotic cells and cause inhibition of Gram-positive bacteria. The different activity in different extracts suggests different compounds with different polarities.     

Preparation and application of an<Emphasis Type="Italic">s</Emphasis>-triazine-based novel<Emphasis Type="Italic">N</Emphasis>-halamine biocide for antimicrobial fibers

N-halamines serve as important antimicrobial agents. Development of this class of compounds has been shown to provide benefits especially from a biocidal point of view. A novels-triazine-basedN-heterocycle, dichloro-m-aminophenyl-hydantoinyl-s-triazine (DAPHT), which could be rendered antimicrobial through exposure to diluted chlorine bleach, was synthesized and characterized by¹H NMR,¹³C NMR, and FT-IR. A finishing method was used to apply theN-halamine precursor onto cotton fabric, and the optimum conditions for finishing were investigated. The DAPHT-treated cotton fabric had durable antimicrobial properties up to 50 standard washing cycles and was rechargeable under normal laundry/bleaching conditions. The antimicrobial efficacy against Gram-positive and Gram-negative bacteria was demonstrated.     

In vitro antioxidant activity of ragweed (Ambrosia artemisiifolia L., Asteraceae) herb

The antioxidant activity in 70% aqueous acetone extracts of the herb of Ambrosia artemisiifolia L., Asteraceae was evaluated with regards to total polyphenol and flavonoid contents. Antioxidant activity has been assessed by two commonly used in vitro tests, based on determination of ferric-reducing antioxidant power (FRAP assay) and DPPH free radical scavenging ability (DPPH assay), against butylated hydroxytoluene (BHT), ascorbic acid and quercetin, which were used as positive control substances. The results of both antioxidant tests showed that the plant material expressed a considerable activity (DPPH IC₅₀ = 27.6 μg/ml; FRAP value = 2.37 mmol Fe²⁺/g), attributed to both flavonoid aglyca and resembling glycosides, as verified by dot-blot TLC analysis.     

Intestinal absorption of D-galactose in the presence of extracts fromPhaseolus vulgaris hulls

The relatively low nutritional value of protein from legume seeds has been attributed to the occurrence of some antinutritional factors and the poor content in sulphur aminoacids, which leads to undesirable physiological and biochemical alterations. However, the intimate nature of these processes remains unclear. In order to evaluate the influence of naturally occurring substances of legume constituents on nutrient utilization, the intestinal absorption of D-galactose in the presence of aqueous or alcoholic extracts, obtained fromPhaseolus vulgaris hulls, has been measured by use of thein vivo successive absorption technique.Aqueous extracts inhibited significantly (p<0.01) the uptake of D-galactose at different times of exposure, while no changes in sugar transport were observed with the alcoholic solutions. Polyamide treatment (a polyphenolic complexing agent) of the aqueous extracts decreased its ability to inhibit sugar uptake. Kinetic studies showed that the aqueous fractions modifyV _max values for D-galactose absorption and alsoK _T data. This inhibition appeared to be reversible after short periods of exposure, affecting mainly the active component of transport. Therefore, it can be suggested that some substances, contained in aqueous extracts ofPhaseolus vulgaris reduce sugar absorption. Furthermore, our studies seem to indicate that polyphenols are, at least partly, involved in this phenomenon.     

Antimicrobial Action of Compounds from Marine Seaweed

Seaweed produces metabolites aiding in the protection against different environmental stresses. These compounds show antiviral, antiprotozoal, antifungal, and antibacterial properties. Macroalgae can be cultured in high volumes and would represent an attractive source of potential compounds useful for unconventional drugs able to control new diseases or multiresistant strains of pathogenic microorganisms. The substances isolated from green, brown and red algae showing potent antimicrobial activity belong to polysaccharides, fatty acids, phlorotannins, pigments, lectins, alkaloids, terpenoids and halogenated compounds. This review presents the major compounds found in macroalga showing antimicrobial activities and their most promising applications.     

Varietal and environmental effect on the glycoalkaloid content of potato (Solanum tuberosum L.)

The tubers of 14 potato varieties were analysed for glycoalkaloids. The level of glycoalkaloids in tubers of all the varieties analysed are within the safe limits for human consumption. The peels of tuber contained about 60–70% of the total glycoalkaloids present in the whole tuber. The levels of glycoalkaloids in leaves and tubers were correlated (r=0.865). There was a significant increase in the content of glycoalkaloids in peels of tubers exposed to sunlight. Glycoalkaloid contents increased at the rate of 1.9mg/100g fresh weight per day in peels of Kufri Jyoti tubers exposed to diffused sunlight.     

Functional Recombinants Designed from a Fetuin/Asialofetuin-Specific Marine Algal Lectin,Rhodobindin

Plant lectins have attracted much attention for biomedical applications including targeted drug delivery system and therapy against tumors and microbial infections. The main problem of using lectins as a biomedical tool is a batch-to-batch variation in isoforms content. The production of lectins using recombination tools has the advantage of obtaining high amounts of proteins with more precise properties, but there are only a handful of functional recombinant lectins presently available. A fetuin/asialo-fetuin specific lectin, Rhodobindin, has unique tandem repeats structure which makes it useful in exploiting for recombinant lectin. We developed three functional recombinant lectins using E. coli expression system: one from full cDNA sequence and two from fragmentary sequences of Rhodobindin. Hemagglutinating activity and solubility of the recombinant lectins were highest at OD 0.7 cell concentration at 20 °C. The optimized process developed in this study was suitable for the quality-controlled production of high amounts of soluble recombinant lectins.     

高粱不同组织浸提液对小麦幼苗的化感作用

为了给小麦合理轮作倒茬提供参考依据,研究了高粱不同组织的水浸提液对小麦幼苗生长的化感作用.结果表明,高粱秆、穗、叶的水浸提液对小麦幼苗的苗高和根长均有极强的化感作用,浸提液在低浓度时促进小麦生长,高浓度抑制小麦生长,且对根的化感作用大于对地上部的化感作用.高浓度高粱浸提液降低了小麦的根系活力和叶片可溶性蛋白含量,提高了小麦叶片的丙二醛(MDA)含量;小麦叶片的超氧化物歧化酶(SOD)、过氧化氢酶(CAT)、过氧化物酶(POD)等酶活性均显著下降.综合来看,高粱不同组织水浸提液对小麦的化感作用表现为秆＞穗＞叶.     

Improvement of the quality and shelf life of wheat bread by fermentation with the antifungal strain Lactobacillus plantarum FST 1.7

Lactobacillus plantarum FST 1.7 was screened for in vitro antimicrobial activity and was shown to be active against spoilage moulds and bacteria. Isolation of antimicrobial compounds from cell-free supernatant identified lactic acid, phenyllactic acid and the two cyclic dipeptides cyclo (l-Leu-l-Pro) and cyclo (l-Phe-l-Pro) as the major components responsible for this activity. L. plantarum FST 1.7 was tested for the ability to produce the antifungal compounds during sourdough fermentation and to produce bread of good quality and increased shelf-life. A rheofermentometer was used to examine the gaseous release and development characteristics of the dough. A range of parameters was determined including pH, TTA and specific loaf volume. The results were compared with those obtained using Lactobacillus sanfranciscensis, a chemically acidified and a non-acidified dough. The quality of sourdough and bread produced using L. plantarum FST 1.7 was comparable to that obtained using common sourdough starters, e.g. L. sanfranciscensis. Sourdoughs and breads were evaluated for the ability to retard growth of Fusarium culmorum and Fusarium graminearum two fungi found on breads. Sourdough and bread produced with strain FST 1.7 showed consistent ability to retard the growth of both Fusarium species, thus indicating that L. plantarum FST 1.7 has also the potential to improve the shelf-life of wheat bread.     

Antioxidant and Cytotoxic Activities of Aphanes arvensis Extracts

The objectives of this study were to examine the free radical scavenging activity and the protective effects against macromolecular oxidation as well as the cytotoxic activity of Aphanes arvensis aqueous and methanolic extracts. Free radical scavenging activity was determined by DPPH method. The methanolic extract showed a scavenging activity nearly equivalent to Trolox and Vitamin C and has an IC₅₀ value of 4.54 μg/mL. Total antioxidant capacity was determined by CUPRAC method. The antioxidant capacity of aqueous and methanolic extract was 0.792 and 1.550 mmol TE/g DWE, respectively. The protective effect of A. arvensis extracts against lipid peroxidation was evaluated using a liposome oxidation system. The methanolic extract was more active than the aqueous extract. The aqueous extract possessed protective effect against protein oxidation in a dose dependent manner. Both extracts showed inhibitory effect on DNA oxidation as measured by plasmid relaxation assay. Results presented here indicate that A. arvensis possess strong antioxidant activity and protective effects with very little cytotoxic effect, and they can therefore be used as a natural additive in food, cosmetic and pharmaceutical industries.