Fe-reducing Power Research Articles

Characterization and antioxidant activity of eumelanin produced by Streptomyces lasalocidi NTB 42

Melanin, a macromolecule derived from the oxidative polymerization of phenolic compounds, possesses notable bioactive attributes and serves as a crucial biological safeguard against deleterious environmental factors. Melanin originates in Streptomyces and is known for its antioxidative properties. This study aimed to characterize and evaluate the antioxidant activity of melanin obtained from Streptomyces lasalocidi NTB 42. Based on 16 S rRNA identification, strain NTB 42 was identified as Streptomyces lasalocidi NTB 42 (OR710932). During melanin biosynthesis, S. lasalocidi NTB 42 had the highest tyrosinase activity on day 5 and the highest L-3,4-dihydroxyphenylalanine concentration on day 6. Melanin NTB 42 exhibited polymorphic and irregular morphology. Melanin NTB 42 characteristics were analyzed using the A650/A500 ratio, UV–visible spectroscopy, Fourier transform infrared spectroscopy, high-performance liquid chromatography, dispersive X-ray spectroscopy, and thermal degradation products based on pyrolysis-gas chromatography-mass spectrometry were identified as eumelanin. The scavenging ability of NTB 42 melanin, as determined by the half maximal inhibitory concentration (IC50), was 70.60 ± 0.40 μg/mL for 2,2-diphenyl-1-picrylhydrazyl and 176.76 ± 0.93 μg/mL for 2,2′-azino-bis(3-ethylbenzothiazolin-6-acid sulfonate radicals. The Fe-reducing power and total antioxidant capacity values were 114.05 ± 0.41 mg AAE/g melanin and 145.10 ± 0.56 mg AAE/g melanin, respectively. This study is the first attempt to characterize the antioxidant properties of eumelanin from S. lasalocidi NTB 42. The antioxidant ability of eumelanin NTB 42 against various free radicals shows promise for further development as an antioxidant.

Synthesis, structural characterization, and quantum chemical study of the 7-acetyl-5-nitrobenzofurans as anticancer agents with antioxidant properties

Synthesis of 7-acetyl-2-aryl-5-nitrobenzofurans 2a–j involved sequential Sonogashira cross-coupling of 2-hydroxy-3-iodo-5-nitroacetophenone with terminal acetylenes and in situ Cacchi-type cycloisomerization of 5-alkynylated intermediates. Hirshfeld's fingerprint diagrams and surface analysis showed varied intermolecular interactions. Additionally, intramolecular interactions were examined using DFT and QTAIM calculations. Benzofuran derivatives were tested for antiproliferative efficacy in vitro against MDA-MB-231 and Caski cell lines. The 1-(5-nitro-2-(p-tolyl)benzofuran-7-yl)ethan-1-one 2h showed promising antiproliferative activity against Caski and MDA-MB-231 cell lines, with IC50 values of 26.96 ± 4.97 µM and 5.13 ± 0.86 µM, respectively, compared to Camptothecin (IC50 = 8.96 ± 0.23 and 24.69 ± 0.26 µM). Derivatives with 2-(4-fluorophenyl)-2c, 2-(4-methoxyphenyl)- 2g, and 2-(3,5-bis(trifluoromethyl)phenyl)-2j groups showed significant antioxidant activity, with Fe-reducing power values of 520.14 ± 1.34 µM, 433.50 ± 1.30 µM, and 466.08 ± 1.91 µM, respectively, compared to ascorbic acid (IC50 = 538.05 µM). The most active molecules that docked with protease (2c, 2g, and 2j) and FKBP12-mTOR (2d, 2h and 2j) active site residues showed significant interactions which were confirmed by Molecular dynamic simulation. ADME investigation indicated drug-like characteristics, safe in silico toxicity, and no carcinogenic or mutagenicity.

Evaluation of drought-tolerant endophytic fungus Talaromyces purpureogenus as a bioinoculant for wheat seedlings under normal and drought-stressed circumstances.

The present work is aimed to hypothesize that fungal endophytes associated with wheat (Triticum aestivum L.) plants can play a variety of roles in biotechnology including plant growth. Out of 67 fungal isolates, five maximum drought-tolerant isolates were used to check their various plant growth-promoting traits, antioxidants, and antifungal activities under secondary screening. Fungal isolate #8TAKS-3a exhibited the maximum drought tolerance capacity and potential to produce auxin, gibberellic acid, ACC deaminase, phosphate, zinc solubilization, ammonia, siderophore, and extracellular enzyme activities followed by #6TAKR-1a isolate. In terms of antioxidant activities, #8TAKS-3a culture also showed maximum DPPH scavenging, total antioxidant, and NO-scavenging activities. However, #6TAKR-1a exhibited maximum total flavonoid content, total phenolic content, and Fe-reducing power and also the highest growth inhibition of Aspergillus niger (ITCC 6152) and Colletotrichum sp. (ITCC 6152). Based on morphological characters and multi-locus phylogenetic analysis of the nuc rDNA internal transcribed spacer region (ITS1-5.8S-ITS2 = ITS), β-tubulin (TUB 2), and RNA polymerase II second largest subunit (RPB2) genes, potent fungal isolate #8TAKS-3a was identified as Talaromyces purpureogenus. Under the in vitro conditions, T. purpureogenus (#8TAKS-3a) was used as a bioinoculant that displayed a significant increase in various physio-biochemical growth parameters under normal and stressed conditions (p < 0.05). Our results indicate that drought stress-tolerant T. purpureogenus can be further used for field testing as a growth promoter.

The effect of Sichuan pepper on gut microbiota in mice fed a high-sucrose and low-dietary fibre diet

Sichuan pepper (Zanthoxylum bungeanum, HJ), a spice widely used in China, has antioxidative, anti-inflammatory, antibacterial, and anti-obesity properties. In this study, to confirm the value of HJ as a functional food, the in vitro antioxidant and bile acid-lowering capacities, as well as the effects on caecal microbiota, were compared with those of cumin (Cuminum cyminum, CM) and coriander (Coriandrum sativum, CR) seeds in Institute of Cancer Research (ICR) mice fed a high-sucrose and low-dietary fibre diet. The total phenolic content, superoxide anion radical-scavenging capacity, and Fe-reducing power of the HJ aqueous solution were higher than those of CM and CR (p < 0.05). The bile acid (taurocholic, glycocholic, and deoxycholic acids)-lowering capacity of the HJ suspension was also higher than those of CM and CR. Compared with mice fed a control diet (no fibre, NF), caecal Lactobacillus gasseri- and Muribaculum intestinale-like bacteria were higher in mice fed a diet containing 5% (w/w) of CM, CR, or HJ for 14days. Bifidobacterium pseudolongum-, Lactobacillus murinus/animalis-, and Faecalibaculum rodentium-like bacteria were significantly increased, while Desulfovibrio-like bacteria were significantly decreased in the HJ group. In addition, CM and HJ may benefit specific metabolic functions of gut microbiota, such as starch, sucrose, and tyrosine metabolism. The tumour necrosis factor (TNF-α) concentration in the spleen tissue of ICR mice was decreased by the intake of spices. However, there were no changes in interleukin-2 (IL-2) and IL-10 levels in HJ fed mice. These results suggested that HJ has potential as a functional food related to gut microbiota. KEY POINTS: • Bididobacterium and Faecalibaculum in mice gut microbiota are increased by Sichuan pepper (HJ). • Desulfovibrionaceae, an inflammatory LPS producer, in mice gut microbiota is decreased by HJ. • HJ decreases pro-inflammatory TNF both in murine spleen tissue and in vitro macrophages.

Detection of indigenous gut bacteria related to red chilli pepper (Capsicum annuum) in murine caecum and human faecal cultures.

Red chilli pepper (Capsicum annuum; RP) is a popular spice containing the active compound capsaicin. Indigenous gut bacteria and metabolism can affect host health. The functions of capsaicin, including the regulation of metabolic health and anti-oxidant properties, may be correlated with the gut microbiota. To identify indigenous gut bacteria that are responsive to RP, Institute of Cancer Research mice fed a diet with no fibre or with 5% (w/w) RP for 14days. Additionally, human stool samples collected from four healthy volunteers were incubated without (control) or with 2% (w/v) RP at 37°C for 24h. Microbiota in murine caecal samples and human faecal cultures were analysed using 16S rRNA (V4) amplicon sequencing. Compared with the microbiota in mice fed no-fibre diets, Lachnospiraceae spp.-, Muribaculaceae spp.-, and Phacaeicola vulgatus-like bacteria were defined as murine RP-responsive indigenous gut bacteria (RP-RIB). In the human faecal cultures, acetate and propionate levels were higher in RP cultures than in the control cultures. Subdoligranulum spp.-, Blautia spp.-, Faecalibacterium prausnitzii-, P. vulgatus-, and Prevotella copri-like bacteria were defined as human RP-RIB. Compared with control culture Fe-reducing power was increased in the culture with RP. RP increases the amount of short-chain fatty acid-producing bacteria and beneficial gut bacteria in mouse and human faecal cultures. Overall, RP could have a positive effect on the host by altering the gut microbiota.

In vitro anti-oxidant, anti-glycation, and bile acid-lowering capacity of chickpea milk fermented with Lactiplantibacillus pentosus Himuka-SU5 and Lactococcus lactis subsp. lactis Amami-SU1

In the present study, we developed new functional food materials from chickpea (Cicer arietinum) milk (CM) with desirable nutritional value, health functions, and rheology to mitigate lifestyle and age-related diseases. The anti-oxidant, anti-glycation, and bile acid-lowering properties of CM fermented with the lactic acid bacteria Lactiplantibacillus pentosus Himuka-SU5 (LpFCM) and Lactococcus lactis subsp. lactis Amami-SU1 (LcFCM) were determined in vitro. L. pentosus Himuka-SU5 and L. lactis Amami-SU1 were found to lower the pH from 6.4 to 4.7 at 12 and 48 h, respectively. The lactic acid concentration in LpFCM and LcFCM was 6.9 and 4.4 mg/mL, respectively. Both starters were found to degrade the dissolved proteins in CM, and L. lactis Amami-SU1 produced ammonia. Though the total phenolic content was slightly lower in LpFCM and LcFCM than in unfermented CM, O2− radical-scavenging capacity, 1,1-diphenyl-2-picrylhydrazyl radical-scavenging capacity, and Fe-reducing power were high in both LpFCM and LcFCM. Anti-glycation in a bovine serum albumin-fructose model and the bile acid-lowering capacities of CM were distinctly increased following fermentation. Based on the results of the present study, we inferred that fermented CM can be considered a desirable food material to prevent and ameliorate chronic lifestyle diseases, particularly in the elderly.

Effects of alginate and laminaran on the microbiota and antioxidant properties of human faecal cultures

Alginate and laminaran are water soluble dietary fibres in brown algae. In a previous study, pure cultures of Bacteroides xylanisolvens, Bacteroides uniformis, and Erysipelaclostridium ramosum increased antioxidant capacities in the broth with alginate and/or laminaran fermentation. This study was conducted to evaluate the presence of the alginate- and laminaran-responsive human gut indigenous bacteria (RIB) and their functions. Briefly, human stool samples were cultured in media without (control), or with 1% (w/v) alginate or laminaran at 37 °C for 24 h under anaerobic conditions. Results showed that during incubation, the pH of the culture reduced with the polysaccharides. Phenol production was clearly suppressed via laminaran supplementation in the faecal sample cultures. The 16S rRNA (V4) gene amplicon sequencing confirmed that B. xylanisolvens-, B. uniformis and E. ramosum-like bacteria were alginate- and/or laminaran-RIB in human gut, although their read numbers differed among individuals. Additionally, some butyrate-producers, such as Faecalibacterium and Roseburia, were also detected as the RIB in alginate and laminaran cultures, respectively. Fermentation increased 1,1-diphenyl-2-picrylhydrazyl and superoxide anion radical-scavenging capacities and the Fe-reducing power of the culture medium. Additionally, the fermented cultures increased the nitric oxide secretion in macrophage like RAW 264.7 cells culture. These results suggest that the interaction of alginate and laminaran with their RIB may have desirable effects on the host as next generation prebiotics when brown algae are ingested.

Extraction of Essential Oil from River Tea Tree (Melaleuca bracteata F. Muell.): Antioxidant and Antimicrobial Properties

Tea tree oil (TTO) from the genus Melaleuca L. has antimicrobial, antibacterial, antifungal, and antioxidant properties and is used by the cosmetic, pharmaceutical, and horticultural industries. In Pakistan, Melaleuca bracteata can be exploited for essential oil purposes, as this species is well adapted to Pakistan’s agroclimatic conditions. The objective of the present study was to evaluate the yield of M. bracteata essential oil together with its antioxidant and antimicrobial properties under local prevailing conditions of the subtropics. Essential oil was extracted through the hydrodistillation method. Using this method, six batches of 8 kg samples (fresh leaves and branches) underwent a distillation process for 4–5 h. The average yield obtained was about 0.2%. The GCMS was used to identify the components of extracted essential oil. Eugenol methyl ether is the major component in extracted essential oil, i.e., 96% of the total. A high content of flavonoids and phenolics and a Fe-reducing power ability of M. bracteata were observed. The oil was also found effective against B. subtilis, B. cereus, White rot, and A. flavus. Hence, it is concluded that there is a possibility to use TTO for its biocidal properties, and it must also be inspected and then commercialized in Pakistan by the agriculture and cosmetic industries.

Induction of browning and antioxidant capacity of cooked shark meats by pre-treatment with fermented rice bran suspension

Abstract Ten % w/v rice bran suspension (RB) were fermented by Saccharomyces cerevisiae Misaki-SU1 and Lactobacillus plantarum Sanriku-SU8 (FRB). Pre-treatment of shark meats in 20% v/v FRB added 10% w/v sucrose and 5% w/v NaCl at 10 °C for 48 h improves the flavour and taste. In the present study, effects of RB and FRB pre-treatments on the browning (Maillard reaction) and antioxidant capacity of retorted (115 °C for 15 min) shark meats. Browning of the meat was suppressed and promoted by RB and FRB, respectively. DPPH radical scavenging was clearly increased by FRB, and its induction was correlated with the increasing a* value of the retorted meat paste. The Fe-reducing power was decreased with RB pre-treatment and it was correlated with the b* value of retorted meat broth. These results suggest that RB-treatment can prevent undesirable browning, and FRB can induce radical scavenging capacity. These are both thought to be useful for improving the quality of sharks and other meats.

In vitro antioxidant, anti-glycation and immunomodulation activities of fermented blue-green algae Aphanizomenon flos-aquae.

To clarify the antioxidant, anti-glycation and immunomodulatory capacities of fermented blue-green algae Aphanizomenon flos-aquae (AFA), hot aqueous extract suspensions made from 10% AFA were fermented by Lactobacillus plantarum AN7 and Lactococcus lactis subsp. lactis Kushiro-L2 strains isolated from a coastal region of Japan. The DPPH and O2- radical scavenging capacities and Fe-reducing power were increased in the fermented AFA. The increased DPPH radical scavenging capacity of the fermented AFA was fractionated to mainly < 3kDa and 30-100kDa. The increased O2- radical scavenging capacities were fractionated to mainly < 3kDa. Anti-glycation activity in BSA-fructose model rather than BSA-methylglyoxal model was increased by the fermentation. The increased anti-glycation activity was fractionated to mainly 30-100kDa. The NO concentration in the murine macrophage RAW264.7 culture media was high with the fermented AFA. The increased immunomodulation capacity was also fractionated to mainly 30-100kDa. These results suggest that the fermented AFA is a more useful material for health foods and supplements.

Induction of superoxide anion radical-scavenging capacity in an argan press cake-suspension by fermentation using Lactobacillus plantarum Argan-L1

The argan tree, Argania spinosa, is only endemic to south-western Morocco. Oils from the argan tree are not only edible, but also used for hair-conditioning, dermocosmetic, and pharmaceutical purposes. The mechanical press method yields approximately 43% argan oil, and a residue, which is called the argan press cake (APC). To elucidate the usefulness of the APC, the effects of fermentation using the bacteria Lactobacillus plantarum Argan-L1, which is isolated from argan fruits, on the in vitro antioxidant properties of a 5% w/v APC-suspension (APC-S), were determined. The main sugar in the APC-S was sucrose, which was converted to lactic acid in the fermented APC-S (F-APC-S). Although the fermentation slightly reduced the phenolic compound content and Fe-reducing power, there was a notable rise in the superoxide anion (O2−) radical scavenging capacity in the F-APC-S. From the results obtained for the ultrafiltered fractions, it can be said that the increase in the O2− radical-scavenging capacity might be due to the presence of <3 kDa compounds, including lactic acid and protein-related compounds. These results suggest that the F-APC-S, which had retained polyphenols and saponins, generated lactic acid and peptides, and thus, Argan-L1 can be used to prepare functional food and cosmetic materials.

Limoniastrum guyonianum prevents H2O2-induced oxidative damage in IEC-6 cells by enhancing enzyamtic defense, reducing glutathione depletion and JNK phosphorylation

Limoniastrum guyonianum is used in several regions of North Africa as a folk medicine. The objective of this study was to determine the in vitro antioxidant activities of L. guyonianum roots and their cytoprotective action on H2O2-challenged rat small intestine epithelial cells (IEC-6 cells). To assess the cytoprotective effect of L. guyonianum extract (LGE), IEC-6 cells were pre-incubated with different LGE concentrations. Then, IEC-6 cultures were exposed to 40μM H2O2 during 4h. Modulation of endogenous antioxidant system including SOD, CAT, MDA, GSH and the expression of possibly involved MAPKs was evaluated. Main results reported that L. guyonianum was rich in polyphenols and exhibited an important antioxidant activity as revealed by different tests (DPPH Assay, IC50=1.6μg/mL; ABTS+ test, IC50=27μg/mL; Fe-reducing power, EC50=44μg/mL). HPLC analysis showed that quercetin, catechin, and isorhamnetin-3-O-rutinoside were major phenolics. The exposure of IEC-6 cells to 40μM H2O2 during 4h resulted in oxidative stress manifested by (i) over 70% cell mortality, (ii) over-activity of CAT (246%), (iii) decrease in GSH level (10.4nmol/mg), (iv) excess in MDA content (18.4nmol/mg), and (v) a trigger of JNK phosphorylation. Pretreatment with LGE, especially at 0.25μg/mL, restored cell viability to 100%, and normal cell morphology in H2O2-chalenged cells. In addition, this extract maintained a high CAT activity, enhanced SOD capacity (120%) and increased GSH level (45.5nmol/mg). Furthermore, reducing cell death seems to be due to dephosphorylated JNK MAPK exerted by L. guyonianum bioactive compounds. In all, L. guyonianum components provided a cross-talk between regulatory pathways, implying their role as cytoprotector against oxidative stress.

Antioxidant and fermentation properties of aqueous solutions of dried algal products from the Boso Peninsula, Japan

Abstract The mineral and saccharide contents, and antioxidant properties in aqueous extract solutions of eleven dried algal products obtained from the Boso Peninsula, Japan, were investigated. Potassium content was high in the brown alga Sargassum fusiforme. Polysaccharides content and viscosity were high in the red algae Gloiopeltis furcata, Chondrus ocellotus and C. elatus. Total phenolic compound content, 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical-scavenging capacity, and Fe-reducing power were high in brown algae Eisenia bicyclis, S. fusiforme and the red alga Pyropia sp. Superoxide anion (O2−) radical-scavenging capacity was high in G. furcata, C. ocellotus, C. elatus and the green alga Monostroma nitidum. Lactobacillus plantarum strains isolated from the coast could ferment G. furcata, C. elatus and M. nitidum. The O2− radical-scavenging capacities of the red algae were increased by fermentation. These results suggest that some macroalgal beach-cast brown algae without fermentation and red algae with fermentation can be utilized as natural resources for functional foods.

Tamarix gallica phenolics protect IEC-6 cells against H2O2 induced stress by restricting oxidative injuries and MAPKs signaling pathways.

Polyphenolic compounds gained interest in the pharmaceutical research area due to their beneficial properties. Herein, antioxidant and cytoprotective capacities of T. gallica extract on H2O2-challenged rat small intestine epithelial cells were investigated. To set stress conditions, IEC-6 cultures were challenged with numerous H2O2 doses and durations. Then, 40μM H2O2 during 4h were selected to assess the cytoprotective effect of different T. gallica extract concentrations. Oxidative parameters, measured through CAT and SOD activities as well as MDA quantification were assessed. In addition, the expression of possibly involved MAPKs was also valued. Main results reported that T. gallica was rich in polyphenols and exhibited an important antioxidant activity (DPPH Assay, IC50=6μgmL-1; ABTS+ test, IC50=50μgmL-1; Fe-reducing power, EC50=100μgmL-1). The exposure of IEC-6 cultures to 40μM H2O2 during 4h caused oxidative stress manifested by (i) over 70% cell mortality, (ii) over-activity of CAT (246%), (iii) excess in MDA content (18.4nmolmg-1) and (iiii) a trigger of JNK phosphorylation. Pretreatment with T. gallica extract, especially when used at 0.25μgmL-1, restored cell viability to 122%, and normal cell morphology in H2O2-chalenged cells. In addition, this extract normalized CAT activity and MDA content (100% and 14.7nmolmg-1, respectively) to their basal levels as compared to control cells. Furthermore, stopping cell death seems to be due to dephosphorylated JNK MAPK exerted by T. gallica bioactive compounds. In all, T. gallica components provided a cross-talk between regulatory pathways leading to an efficient cytoprotection against harmful oxidative stimulus.

Anti-glycation properties of the aqueous extract solutions of dried algae products harvested and made in the Miura Peninsula, Japan, and effect of lactic acid fermentation on the properties

To clarify the anti-oxidant and anti-glycation properties of traditional edible algae, aqueous extract solutions (AESs) from eight dried algal products that were commercially available in the Miura Peninsula of Japan were prepared. AESs of the red alga, Pyropia sp. (nori), demonstrated strong Fe-reducing power with a high total phenolic compound content. On the other hand, the sporophyll of the brown alga Undaria pinnatifida (mekabu) exhibited high superoxide anion radical-scavenging capacity. Anti-glycation activity in bovine serum albumin (BSA)-fructose (Fru) and in BSA-methylglyoxal (MGO) was high for nori and the stem of Sargassum fusiforme (naga-hijiki). The results of the BSA-MGO model agreed with those of the phenolic content and Fe-reducing power. Anti-glycation activities of mekabu, Sargassum horneri (akamoku), naga-hijiki, the frond of U. pinnatifida (wakame), and Gelidium elegans (tengusa) in the BSA-Fru model were clearly increased by fermentation with Lactobacillus plantarum Miura-SU1 isolated from the Miura Peninsula. The results of the present study suggest that, once fermented with lactic acid bacteria (LAB), akamoku and other edible algae will have a potential role in preventing diabetes- and aging-related glycation.

Anti-glycation properties of the aqueous extract solutions of dried algae products and effect of lactic acid fermentation on the properties

The antioxidant and anti-glycation properties in aqueous extract solutions (AESs) of 11 dried algae products were investigated. AESs of brown algae Ecklonia kurome (kurome) and Ecklonia stolonifera (tsuruarame) showed a strong DPPH radical-scavenging capacity and Fe-reducing power with high total phenolic compound content. On the other hand, superoxide anion radical-scavenging capacities of Porphyra sp. (iwanori, red alga), sporophyll of Undaria pinnatifida (mekabu, brown alga), and Gelidiaceae sp. (tengusa, red alga) were also high. Anti-glycation activities in BSA-fructose and BSA-methylglyoxal glycation were also high in kurome, while iwanori showed high activity. Results of the BSA-fructose model agreed with those of superoxide anion radical-scavenging. On the other hand, those of the BSA-methylglyoxal model agreed with those of the phenolic content, DPPH radical-scavenging capacity, and Fe-reducing power. Anti-glycation activities of iwanori, U. pinnatifida (wakame), and mekabu in the BSA-fructose model were clearly increased by fermentation with Lactobacillus plantarum AN6.

In vitro antioxidant and anti-inflammation properties of lactic acid bacteria isolated from fish intestines and fermented fish from the Sanriku Satoumi region in Japan

The Ministry of the Environment, Government of Japan, defines a Satoumi as a coastal area where biological productivity and biodiversity has increased through human interaction. As a way to identify new starters and probiotics, we isolated and screened lactic acid bacteria (LAB) with acid, bile, and salt resistance from the intestines of 23 fish and 11 fermented fish samples obtained from the northeastern (Sanriku) Satoumi region of Japan. Of the 301 isolates, 75 strains were selected as LAB, 6 of which clearly showed increased antioxidant activities (DPPH and O2− radical scavenging and Fe-reducing power) in their cultured broth. Four isolates (S-SU1, 3–5) were identified as Lactobacillus plantarum. The two other strains (S-SU2, 6) identified were Lactococcus lactis and Pediococcus pentosaceus. In these in vitro assays, Lc. lactis S-SU2, isolated from sea pineapple kimchi showed the highest radical scavenging capacity. Moreover, the protective effect of heat-killed cells against the toxicity of 3mM H2O2 on Saccharomyces cerevisiae was the highest for Lb. plantarum S-SU1 isolated from a salted squid product, followed by P. pentosaceus S-SU6 isolated from the intestines of blue mackerel. Furthermore, Lb. plantarum S-SU5 showed inhibitory effect against the toxicity of 3mM H2O2 in human enterocyte-like HT-29-luc cells and on nitrite (NO) production in mouse RAW264.7 macrophage cells, which was induced by Escherichia coli O111 lipopolysaccharide (LPS). These results suggest that the selected LAB strains are potential starters and/or functional components with antioxidant and anti-inflammatory properties.

Effects of drought stress on quantitative and qualitative yield and antioxidative activity of Bunium persicum

Drought stress is one of the growing concerns in agriculture management around the world. Adopting tolerant plants to drought conditions could be an appropriate approach to this problem. Bunium persicum is one of the most important medicinal plants of Iran and Turkey as well as neighbouring countries and has been forced into endangered plant status due to mismanagement of its wild habitats. An experiment was conducted in order to evaluate drought tolerance of Bunium persicum and the effects of drought on its essential oil qualitative properties. Two separate plans based on randomised complete block design were performed with 4 drought levels (irrigation after 60, 90, 120, and 150 mm of evaporation from an evaporation basin) and 3 replications. Drought treatments were applied after the stem elongation and flowering stages. Results indicated that applied drought treatments reduced yield and yield components of plants in both growth stages. Some differences were observed in yield components when plants were exposed to drought stress at different growth stages. The essential oil percentage of Bunium persicum was affected by drought conditions, and it was elevated along with increasing drought levels. Due to reduced seed yield, essential oil yield was significantly decreased. Antioxidative activity assessment of seed extracts revealed that drought had positive effects on antioxidant parameters, including 2'-diphenyl 1-picrylhydrazyl radical scavenging activity, hydrogen peroxide scavenging activity, and Fe-reducing power. Phenol content was also improved through applied drought treatments. In general, these results showed the high tolerance of Bunium persicum to drought and also revealed positive effects of drought on the antioxidative activities of plant seeds.

Effects of holdfast of Laminaria japonica on listeria invasion on enterocyte-like Caco-2 cells and NO production of macrophage RAW 264.7 cells.

Listeria monocytogenes (Lm) causes food poisoning in humans mainly through consumption of ready-to-eat foods. Immunocompromised persons are at the highest risk for infection. We investigated effects of crude soluble polysaccharides (SPS) and ethanolic extract (EE) fractions of frond (kombu) and holdfast (ganiashi) parts of Laminaria japonica on Lm invasion into human enterocyte-like Caco-2 cells and immune and/or inflammatory reactions of murine macrophage RAW 264.7 cells. Recovery and viscosity were high in kombu SPS. Total phenolic content and antioxidant activities (2,2-diphenyl-1-picrylhydrazyl radical scavenging capacity and Fe-reducing power) were higher in ganiashi EE. EE of ganiashi, rather than kombu, suppressed the Lm invasion into the differentiated Caco-2 cells, though the inhibitory effect of SPS was not significant. Ganiashi SPS increased the nitric oxide (NO) production of intact RAW 264.7 cells. On the other hand, the NO production from Escherichia coli O111 lipopolysaccharide-activated cells was suppressed by kombu SPS and ganiashi EE. These results suggest that L. japonica, particularly ganiashi, might suppress the invasion and infection of Lm and also the inflammation.

Solvent effects on Antioxidants and biological activities of the halophyte Nitraria retusa (Forssk.) Asch

Nitraria retusa (Forssk.) Asch. is a traditional medicinal species widely used as anti-inflammatory and cicatrizing agent. In this work, two fractions (non-polar and polar) of Nitraria leaves, after fractionation by solvent mixture (chloroform/methanol/water, 12/5/3), were investigated on their phenolic content, antioxidant activity (using several tests) and antimicrobial capacity against human pathogen strains. Moreover, phenolic and fatty acid compositions were identified using RP-HPLC and GC/MS, respectively. Results showed that phenolic contents and antioxidant activities varied considerably as function of solvent polarity. Polar fraction leaves (methanol/water) showed the highest polyphenol (7.97mg GAE/g DW) and tannin (1.78mg CE/g DW) contents, while chloroform fraction (non-polar) exhibits the highest content of flavonoids (2.74mg CE/g DW). Moreover, antiradical activity against DPPH, and β-carotene bleaching test (IC50 values were 39, 700µg.ml-1, respectively) and Fe-reducing power (EC50=410µg ml-1) were more important in leaf non-polar fraction as compared to polar fraction. Besides, chloroform fraction was more efficient against all human pathogen strains mainly Escherichia coli and Staphylococcus aureus. The HPLC analysis showed two major phenolic compounds: trans-4-hydroxy-3-methoxycinnamic acid (ferulic acid) and p-coumaric acid. The major fatty acids identified by GC/MS were palmitic acid (28.04%), and polyunsaturated acids (48.78%) are characterized by linolenic acid (29.69%) and α-linolenic acid (omega 3) (19.09%). These results indicate that selective extraction of bioactive molecules from natural sources as halophyte species, by appropriate solvents, is important for obtaining fractions with high biological activities which can be used as preservative ingredients in food, cosmetic and/or pharmaceutical industries.