Cytotoxic, Cellular Antioxidant, and Antiglucuronidase Properties of the Ethanol Leaf Extract from Bulbine asphodeloides.

Bulbine asphodeloides (L.) Spreng (Xanthorrhoeaceae family), popularly known in South Africa as "ibhucu" or "Balsamkopieva," is a perennial plant traditionally used to treat skin diseases, including sunburns, rough skin, dressing burns, itches, and aging. The present study reports the cytotoxic, cellular antioxidant, and antiglucuronidase properties of the ethanol leaf extract from B. asphodeloides. The cytotoxic effect of the plant extract on human dermal fibroblast (MRHF) cells was evaluated by the bis-Benzamide H 33342 trihydrochloride/propidium iodide (Hoechst 33342/PI) dual-staining method. A validated biological cell-based assay was used to determine the cellular antioxidant activity of the extract. The antiglucuronidase and metal chelating activities were evaluated using standard in vitro methods. Lipopolysaccharide- (LPS-) induced RAW 264.7 cell model was used to determine the anti-inflammatory effect of the plant extract, and the immune-modulatory activity was performed using RAW 264.7 cells. The extract demonstrated no cytotoxic effect towards the MRHF cells at all the tested concentrations. Furthermore, the extract also possessed significant cellular antioxidant and antiglucuronidase activities, but a weak effect of metal chelating activity in a dose-dependent manner. However, the extract showed no significant anti-inflammatory and immune-stimulatory activities. Overall, the results showed that B. asphodeloides may be a useful therapeutic agent for the treatment of skin diseases, therefore supporting its ethnomedicinal usage.

Quantification of endospores in ancient permafrost using time-resolved terbium luminescence.

We describe herein a simple procedure for quantifying endospore abundances in ancient and organic-rich permafrost. We repeatedly (10x) extracted and fractionated permafrost using a tandem filter assembly composed of 3 and 0.2 µm filters. Then, the 0.2 µm filter was washed (7x), autoclaved, and the contents eluted, including dipicolinic acid (DPA). Time-resolved luminescence using Tb(EDTA) yielded a LOD of 1.46 nM DPA (6.55 × 103 endospores/mL). In review, DPA/endospore abundances were ~2.2-fold greater in older 33 ky permafrost (258 ± 36 pmol DPA gdw-1; 1.15 × 106 ± 0.16 × 106 spores gdw-1) versus younger 19 ky permafrost (p = 0.007297). This suggests that dormancy increases with permafrost age.

Isolation and Sequencing of Cu-, Fe-, and Zn-Binding Whey Peptides for Potential Neuroprotective Applications as Multitargeted Compounds.

This study aims to isolate metal-binding peptides and synthesize promising amino acid sequences to potentially act as neuroprotective compounds in the future, targeting different mechanisms. Fractions of whey metal-binding peptides (Cu, Fe, and Zn) isolated by immobilized metal affinity chromatography showed different amino acid profiles according to the metal. The Cu-binding peptides presented roughly twofold increase in the in vitro antioxidant, as assessed by oxygen radical absorbance capacity and anticholinesterase activities over the hydrolysate. This is probably because of the higher concentration of aromatic and basic residues, the latter being crucial for binding to the anionic sites of acetylcholinesterase. Six peptide sequences were synthesized based on the metal-binding sites, molecular mass, hydrophobicity, and bioactivity probability. Among the synthetic peptides, the VF dipeptide stood out both for its in vitro antioxidant and anticholinesterase activities. This peptide, as well as the fraction of Cu-binding peptides, should be further studied because it may act through different mechanisms related to neurodegenerative diseases, in addition to the chelation of the excess of metals in the central nervous system.

In Vitro and In Vivo Antioxidant Activity of Agave sisalana Agro-Industrial Residue.

Agave sisalana agro-industrial residue has considerable potential against damage associated with oxidative stress and skin aging. This study aims to demonstrate, in vitro and in vivo, the potential of Agave sisalana agro-industrial residue as a safe and effective alternative for the prevention of damage caused by oxidative stress and aging. The antioxidant activity was evaluated in vitro (total antioxidant capacity, reducing power, DPPH radical scavenging, metal chelating (Fe2+ and Cu2+), and hydroxyl radical scavenging) and in vivo using the Caenorhabditis elegans organism model. The extract showed in vitro antioxidant activity in all tests performed. Tests with C. elegans showed that the extract was able to reduce the intracellular levels of reactive oxygen species (ROS) and increase the survival rate of worms. A downregulation of gst-4::GFP expression suggests a direct action against free radicals. Agave sisalana agro-industrial residue extract (AsRE) can therefore be considered as a source of antioxidant biomolecules, and the use of this agro-industrial residue in a new production process can lead to sustainability and socioeconomic development.

Recovery of antioxidant and antimicrobial peptides through the reutilization of Nile perch wastewater by biodegradation using two Bacillus species.

Nile perch wastewater was biodegraded using two Bacillus species to recover bioactive substances to enhance its reutilization value. The two Bacillus species successfully produced low-molecular-weight substances with a 47.8% degree of hydrolysis. The antioxidant activities of the Nile perch wastewater increased as the biodegradation proceeded, and the culture supernatant exhibited the highest DPPH (80.1%), ABTS (93.1%) and Fe2+ chelating (88.5%) antioxidant activities at 60 h. The antioxidant potential of the biodegraded Nile perch wastewater was found to be higher than those of other fish hydrolysates. Moreover, the biodegraded Nile perch wastewater exhibited effective antimicrobial activity against Vibrio vulnificus, exhibiting a minimal inhibitory concentration of 585 µg mL-1. Two-dimensional thin layer chromatography analysis revealed the specific amino acids responsible for the antioxidant activity, and molecular-weight cut-off ultrafiltration revealed that the <2-kDa fraction exhibited the highest antioxidant activity with the lowest IC50 values (0.43 and 0.22 mg mL-1 for DPPH and ABTS antioxidant activities, respectively). This is the first report of the reutilization of Nile perch wastewater as a natural antioxidant and antimicrobial ingredient for nutraceuticals.

Chromatographic separation simulation of metal-chelating peptides from surface plasmon resonance binding parameters.

Some metal-chelating peptides have antioxidant properties, with potential nutrition, health, and cosmetics applications. This study aimed to simulate their separation on immobilized metal ion affinity chromatography from their affinity constant for immobilized metal ion determined in surface plasmon resonance, both technics are based on peptide-metal ion interactions. In our approach, first, the affinity constant of synthetic peptides was determined by surface plasmon resonance and used as input data to numerically simulate the chromatographic separation with a transport-dispersive model based on Langmuir adsorption isotherm. Then, chromatographic separation was applied on the same peptides to determine their retention time and compare this experimental tR with the simulated tR obtained from simulation from surface plasmon resonance data. For the investigated peptides, the relative values of tR were comparable. Hence, our study demonstrated the pertinence of such numerical simulation correlating immobilized metal ion affinity chromatography and surface plasmon resonance.

Milk thistle (Silybum Marianum) as an antidote or a protective agent against natural or chemical toxicities: a review.

Biological and chemical agents cause dangerous effects on human health via different exposing ways. Recently, herbal medicine is considered as a biological and safe treatment for toxicities. Silybum marianum (milk thistle), belongs to the Asteraceae family, possesses different effects such as hepatoprotective, cardioprotective, neuroprotective, anti-inflammatory and anti-carcinogenic activities. Several studies have demonstrated that this plant has protective properties against toxic agents. Herein, the protective effects of S. marianum and its main component, silymarin, which is the mixture of flavonolignans including silibinin, silydianin and silychristin acts against different biological (mycotoxins, snake venoms, and bacterial toxins) and chemical (metals, fluoride, pesticides, cardiotoxic, neurotoxic, hepatotoxic, and nephrotoxic agents) poisons have been summarized. This review reveals that main protective effects of milk thistle and its components are attributed to radical scavenging, anti-oxidative, chelating, anti-apoptotic properties, and regulating the inflammatory responses.

Inhibition of Amyloid ß Aggregation Using Optimized Nano-Encapsulated Formulations of Plant Extracts with High Metal Chelator Activities.

BACKGROUND: The role of Fe+2, Cu+2 and Zn+2 in facilitating aggregation of Amyloid ß (Aß) and consequently, the progression of Alzheimer's disease (AD) is well established. OBJECTIVE: Development of non-toxic metal chelators is an emerging era in the treatment of AD, in which complete success has not been fully achieved. The purpose of this study was to determine plant extracts with high metal chelator and to encapsulate them in nano-micellar systems with the ability to pass through the Blood Brain Barrier (BBB). METHODS: Extracts of 36 different Anatolian plants were prepared, total phenolic and flavonoid contents were determined, and the extracts with high content were examined for their Fe+2, Cu+2 and Zn+2 chelating activities. Apolipoprotein E4 (Apo E) decorated nano-formulations of active extracts were prepared using Poly (Lactide-co-Glycolide) (PLGA) (final product ApoEPLGA) to provide BBB penetrating property. RESULTS: Verbascum flavidum aqueous extract was found as the most active sample, incubation of which, with Aß before and after metal-induced aggregation, resulted in successful inhibition of aggregate formation, while re-solubilization of pre-formed aggregates was not effectively achieved. The same results were obtained using ApoEPLGA. CONCLUSION: An optimized metal chelator nano-formulation with BBB penetrating ability was prepared and presented for further in-vivo studies.

The purification, identification and bioactivity study of a novel calcium-binding peptide from casein hydrolysate.

In this study, a novel calcium-binding peptide from casein hydrolysate was purified using reversed-phase high performance liquid chromatography and sequenced by high-performance liquid chromatography-mass spectrometry (MS)/MS. The amino acid sequence of the calcium-binding peptide was identified as VLPVPQK (N- to C-terminal, MW = 779.4960 Da). The calcium binding characteristics of VLPVPQK were further investigated using UV absorption spectroscopy, zeta potential and isothermal titration calorimetry (ITC). The results showed that VLPVPQK has a strong calcium binding activity (129.46 mg g-1), 312% higher than that of 3-hour enzymatic hydrolysates. VLPVPQK could chelate calcium with a 1 : 3 stoichiometry, causing a decrease in the positive charge of the peptide-Ca2+ complex. Furthermore, VLPVPQK could effectively enhance calcium transport and absorption in a concentration-dependent manner in Caco-2 cell monolayers, suggesting that VLPVPQK has the potential to be developed as a nutraceutical additive.

Chemistry and Biology of Siderophores from Marine Microbes.

Microbial siderophores are multidentate Fe(III) chelators used by microbes during siderophore-mediated assimilation. They possess high affinity and selectivity for Fe(III). Among them, marine siderophore-mediated microbial iron uptake allows marine microbes to proliferate and survive in the iron-deficient marine environments. Due to their unique iron(III)-chelating properties, delivery system, structural diversity, and therapeutic potential, marine microbial siderophores have great potential for further development of various drug conjugates for antibiotic-resistant bacteria therapy or as a target for inhibiting siderophore virulence factors to develop novel broad-spectrum antibiotics. This review covers siderophores derived from marine microbes.

Evaluating the efficacy of a ferrous-ion-chelating peptide from Alaska pollock frame for the improvement of iron nutritional status in rats.

This study aimed to investigate the effects of ferrous-ion-chelating peptides from Alaska pollock frames (APFP-Fe) on iron deficiency in anaemic rats. We hydrolysed the Alaska pollock frames to obtain a peptide with an average molecular weight of 822 Da. The bioavailability of APFP-Fe was tested using animal experiments. Wistar rats were randomly divided into six groups: an iron deficiency control group, a normal control group, and iron deficiency groups treated with ferrous sulfate (FeSO4) or low-, medium-, or high-dose APFP-Fe. Rats in the iron deficiency groups were fed an iron-deficient diet to establish the iron deficiency anaemia (IDA) model. After the model was established, different iron supplements were given to rats once per day via intragastric administration for 21 days. The results showed that APFP-Fe had restorative effects, returning the body weight, weight gain, height, and haematological parameters in IDA rats to normal levels. In addition, compared with FeSO4, APFP-Fe promoted significant weight gain and effectively improved haemoglobin, serum iron and transferrin levels, and recovery of the capacity of iron binding with transferrin, especially at the medium and high doses. These findings suggest that APFP-Fe is an effective source of iron for improving the iron nutritional status in IDA rats and shows promise as a new source of iron supplementation.

Preparation of Chlorella vulgaris polysaccharides and their antioxidant activity in vitro and in vivo.

In the present study, six different polysaccharides (RFPs, MAPs, UWPs, AEPs, HWPs and CEPs) were extracted from Chlorella vulgaris using repeated freeze-thawing, microwave-assisted-, ultrasonic wave-, alkali-, hot water-, and cellulase-based methods; and antioxidant property assays were performed both in vitro and in vivo. Radical-scavenging capacity (using DPPH, superoxide and hydroxyl radicals) and metal chelating ability were assessed in vitro; Caenorhabditis elegans was used to assess antioxidant effects in vivo. Based on the in vitro screening tests, UWPs exhibited high antioxidant capacity. The UWP yield was 17.1% ±â€¯2.2%; the DPPH-, superoxide-, and hydroxyl radical-scavenging rates were 65.1% ±â€¯2.4%, 61.2% ±â€¯2.7%, and 56.2% ±â€¯2.2%, respectively, and the metal chelating ability was 63.6% ±â€¯2.5% at a concentration of 0.4 mg/mL. UWPs also exhibited high antioxidant activity in vivo. UWPs significantly increased the lifespan of C. elegans under oxidative stress induced by hydrogen peroxide compared with the control group, enhanced stress-resistance-related enzymes, including catalase and superoxide dismutase by 7.29% ±â€¯1.8% and 24.41% ±â€¯4.8%, respectively. The results of the present study indicate that the extraction methods of C. vulgaris polysaccharides were a key factor influencing antioxidant activity.

Streptomyces sp. MUM273b: A mangrove-derived potential source for antioxidant and UVB radiation protectants.

Microbial natural products serve as a good source for antioxidants. The mangrove-derived Streptomyces bacteria have been evidenced to produce antioxidative compounds. This study reports the isolation of Streptomyces sp. MUM273b from mangrove soil that may serve as a promising source of antioxidants and UV-protective agents. Identification and characterization methods determine that strain MUM273b belongs to the genus Streptomyces. The MUM273b extract exhibits antioxidant activities, including DPPH, ABTS, and superoxide radical scavenging activities and also metal-chelating activity. The MUM273b extract was also shown to inhibit the production of malondialdehyde in metal-induced lipid peroxidation. Strong correlation between the antioxidant activities and the total phenolic content of MUM273b extract was shown. In addition, MUM273b extract exhibited cytoprotective effect on the UVB-induced cell death in HaCaT keratinocytes. Gas chromatography-mass spectrometry analysis detected phenolics, pyrrole, pyrazine, ester, and cyclic dipeptides in MUM273b extract. In summary, Streptomyces MUM273b extract portrays an exciting avenue for future antioxidative drugs and cosmeceuticals development.

Role of acemannan O-acetyl group in murine radioprotection.

Present study was designed to investigate the role of acemannan acetyl group in murine radioprotection. Acemannan, extracted from Aloe vera gel, has molecular weight of 1.02 × 106 Da and mainly composed of mannose (84.9%), glucose (7.2%), and galactose (3.9%), with backbone of (1→4)-linked mannose and glucose. Acemannan was over-acetylated and deacetylated to investigate the role of acetyl group. Acetylation enhances acemannan viscosity and thermal stability. Free radicals scavenging and Fenton reaction inhibition was mediated by acemannan acetyl and hydroxyl group respectively. Native or over-acetylated or deacetylated acemannan pre-treatment to mice has shown to reduce the γ-radiation-induced oxidative damage, and hematopoietic injuries by free radical scavenging and microphage activation (secretes pro-hematopoietic factors through TLR-4) respectively. Over-acetylated acemannan has stronger effects on immunomodulation/radioprotection. In summary, acemannan acetyl-group modulates immune system, while hydroxyl-group participate in free radical scavenging, and present finding can be employed in food and pharma industries for enhancing polysaccharide bioactivity.

An overview of plant-based interventions to ameliorate arsenic toxicity.

The industrial and technological advancements in the world have also contributed to the rapid deterioration in the environment quality through introduction of obnoxious pollutants that threaten to destroy the subtle balance in the ecosystem. The environment contaminants cause severe adverse effects to humans, flora and fauna that are mostly irreversible. Chief among these toxicants is arsenic, a metalloid, which is considered among the most dangerous environmental toxins that leads to various diseases which affect the quality of life even when present in small quantities. Treatment of arsenic-mediated disorders still remains a challenge due to lack of effective options. Chelation therapy has been the most widely used method to detoxify arsenic. But this method is associated with deleterious effects leading various toxicities such as hepatotoxicity, neurotoxicity and other adverse effects. It has been discovered that indigenous drugs of plant origin display effective and progressive relief from arsenic-mediated toxicity without any side-effects. Further, these phytochemicals have also been found to aid the elimination of arsenic from the biological system and therefore can be more effective than conventional therapeutic agents in ameliorating arsenic-mediated toxicity. This review presents an overview of the toxic effects of arsenic and the therapeutic strategies that are available to mitigate the toxic effects with emphasis on chelation as well as protective and detoxifying activities of different phytochemicals and herbal drugs against arsenic. This information may serve as a primer in identifying novel prophylactic as well as therapeutic formulations against arsenic-induced toxicity.

Extraction, preliminary characterization and in vitro antioxidant activity of polysaccharides from Oudemansiella radicata mushroom.

Oudemansiella radicata mushroom has many functions. Optimal condition of extracting its polysaccharides (ORP) with a yield of 5.85 ±â€¯0.13% were determined by using RSM: extraction temperature 84 °C, extraction time 2.3 h and ratio of water to raw material 20.0 mL/g. ORP-1, ORP-2 and ORP-3 were further obtained by chromatography with an average molecular of 13,921 Da, 14,942 Da and 10,209 Da, respectively. ORP-1 is mainly composed of mannose, ribose, glucose, galactose and xylose in a ratio of 2.46:2.63:3.89:3.22:2.78; ORP-2 is mainly composed of ribose, glucose and xylose in a ratio of 2.63:3.38:2.65; ORP-3 is mainly composed of glucose, xylose in a ratio of 3.38: 2.65. ORP exhibits relatively strong in vitro antioxidant activity. Except crude ORP, ORP-1 has the highest DPPH and ABTS radical scavenging activity, and ORP-3 shows the strongest hydroxyl radical scavenging activity and ferrous ion chelating activity, while the three fractions have no significance in scavenging radical superoxide anion.

Catenulobactins A and B, Heterocyclic Peptides from Culturing Catenuloplanes sp. with a Mycolic Acid-Containing Bacterium.

The production of two new heterocyclic peptide isomers, catenulobactins A (1) and B (2), in cultures of Catenuloplanes sp. RD067331 was significantly increased when it was cocultured with a mycolic acid-containing bacterium. The planar structures and absolute configurations of the catenulobactins were determined based on NMR/MS and chiral-phase GC-MS analyses. Catenulobactin B (2) displayed Fe(III)-chelating activity and moderate cytotoxicity against P388 murine leukemia cells.

New Sources of Calcium (Chicken Eggshells, Chelates) - Preparation of Raw Material and Tablets.

BACKGROUND: There are many calcium supplements available in the market, especially those containing calcium in the form of carbonate, which unfortunately is not absorbed by the body to a sufficient degree. METHOD: Therefore, an attempt was made to prepare new sources of calcium, consuming the chicken eggshells as natural raw materials, which were used in preparation of tablets containing calcium carbonate and calcium citrate as well as tablets with calcium carbonate and calcium bisglycinate. The influence of raw material properties on the pharmaceutical availability of calcium from the obtained tablets was investigated. RESULTS: Based on the obtained calcium release profiles from the prepared tablets, it was found that the optimal source of calcium is a preparation containing calcium from chicken eggshells. It was found that both chicken eggshells and calcium bisglycinate (chelate) may be new, prospective sources of calcium. Calcium citrate prepared using eggshells as starting materials and bisglycinate is completely released within no more than 150 minutes. CONCLUSION: In turn, calcium carbonate added to calcium bisglycinate statistically significantly prolonges the release of calcium ions to 4 hours.

Isolation and Identification of Tyrosinase-Inhibitory and Copper-Chelating Peptides from Hydrolyzed Rice-Bran-Derived Albumin.

Rice-bran albumin (RBAlb), which shows higher tyrosinase-inhibitory activity than other protein fractions, was hydrolyzed with papain to improve the bioactivity. The obtained RBAlb hydrolysate (RBAlbH) was separated into 11 peptide fractions by RP-HPLC. Tyrosinase inhibition and copper chelation activities decreased with increasing retention times of the peptide fractions. RBAlbH fraction 1, which exhibited the greatest activity, contained 13 peptides whose sequences were determined by using LC-MS/MS. Most of the peptide sequences contained features of previously reported tyrosinase-inhibitory and metal-chelating peptides, especially peptide SSEYYGGEGSSSEQGYYGEG. RBAlbH fraction 1 showed more effective tyrosinase inhibition (IC50 = 1.31 mg/mL) than citric acid (IC50 = 9.38 mg/mL), but it was less effective than ascorbic acid (IC50 = 0.03 mg/mL, P ≤ 0.05). It showed copper-chelating activity (IC50 = 0.62 mg/mL) stronger than that of EDTA (IC50 = 1.06 mg/mL, P ≤ 0.05). These results suggest that RBAlbH has potential as a natural tyrosinase inhibitor and copper chelator for application in the food and cosmetic industries.

Multidirectional investigations on different parts of Allium scorodoprasum L. subsp. rotundum (L.) Stearn: Phenolic components, in vitro biological, and in silico propensities.

Allium species have been widely used for culinary and medicinal purposes. This study attempts for the first time to investigate into the enzyme inhibitory potential of different plant parts of Allium scorodoprasum L. subsp. rotundum (L.) Stearn, also known as wild garlic or leek in Turkey. The antioxidant and enzyme inhibitory potential of the flower, stem, and bulb extracts of A. scorodoprasum were assessed using in vitro bio-assays. The phenolic composition of the different plant parts was also established. The flower extract, having high phenolic content (27.69 mg GAEg extract), showed potent antioxidant activity as a metal chelating agent (22.27 mg EDTAE/g extract), radical scavenger (34.83 and 66.02 mg trolox equivalent (TE)/g extract, for 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) assays, respectively) and reducing agent (90.53 mg TE/g extract, for the cupric reducing antioxidant capacity assay). Besides, the flower extract was a potent inhibitor of butyrylcholinesterase (3.16 mg galantamine equivalent (GALAE)/g extract) and tyrosinase (55.21 mg kojic acid equivalent/g extract). The flower extract was rich in rosmarinic acid. In silico studies revealed that rosmarinic acid established several hydrogen bonds and π-π interactions in the enzymatic cavity of butyrylcholinesterase. On the other hand, the stem extract of A. scorodoprasum showed inhibitory action against acetylcholinesterase (2.17 mg GALAE/g extract) and α-amylase (0.55 mmol acarbose equivalent/g extract). Interestingly, we noted that the bulb extract of A. scorodoprasum, inferior in phenolic compounds, showed the least activity. These results suggest that the different plant parts of A. scorodoprasum possessed different biological activities and might be used as a medicinal food plants for specific therapeutic applications.