Free Radical Scavenging, Metal Chelating and Singlet Oxygen Quenching Activity of Fractionated Brown Seaweed Sargassum hystrix Extract

Ultrasound-assisted extraction of phenolics from Sargassum carpophyllum - A kinetics study

The species of the brown macroalgal genus Sargassum are distributed globally and contain many bioactive compounds. In this study, ultrasound-assisted extraction (UAE) was applied to obtain phenolic compounds with strong antioxidant activity from Sargassum carpophyllum collected along the coastline of Weizhou Island in the South China Sea. The influence of different variables such as the solid-liquid ratio (1:5-1:30 g · mL-1), ultrasonic power (160-280 W), duty circle ratio (DCR, 1/3-1/1), and ethanol concentration (30% to ~90%) were studied using a single factor design. The extraction kinetics were investigated using the Peleg model and second-order kinetics model, and the second-order model described the extraction procedure better than the Peleg model. Total phenol content (TPC) values of 3.316, 2.964, 2.741, and 3.665 mg phloroglucinol (PHG) · g-1 algae were achieved at a higher solid-liquid ratio (1:30 g · mL-1), higher ultrasonic power (280 W), a higher DCR (1/1), and a moderate ethanol concentration (50%), respectively. However, a slightly different result was observed in the extract obtained, with total phenol contents (TPCextract) of 52.99, 65.00, 46.22, and 55.10 mg PHG · g-1 extract and DPPH radical scavenging activity (IC50) of 0.096, 0.066, 0.131, and 0.136 mg extract · mL-1 observed at 50% ethanol, 1:5 g m· mL-1, 2/3 DCR, and 200 W respectively. All variables studied influenced the extraction kinetics by altering the extraction rate and the TPC at equilibrium. As for the bioactivities in the extract, a larger solid-liquid ratio and greater ultrasonic power may not contribute because of their ability to extract non-phenolic components simultaneously, leading to reduced overall bioactivities. The results of the present study provide essential information for future UAE process design and optimization for extracting phenolics from S. carpophyllum through mathematical modeling and could be regarded as important reference for obtaining value-added products from other macroalgae species.

Anti-Inflammatory, Antioxidant and Enzyme Inhibition Activities in Correlation with Mycochemical Profile of Selected Indigenous Ganoderma spp. from Balkan Region (Serbia)

The aim of this research work was to study the bioactivity potentials (antioxidant, anti-inflammatory, and enzyme inhibitory) of ethanol (EtOH), water (H₂ O) and chloroform (CHCl₃ ) extracts of G. applanatum, G. lucidum, G. pfeifferi and G. resinaceum as well as their mycochemical profile: the total content of phenolics (TP) and sugars (TS) and LC/MS/MS detection of phenolics. LC/MS/MS profile showed that p-hydroxybenzoic and protocatechuic acids were mostly found. The highest ABTS and DPPH activities were detected in polar G. applanatum extracts (159.84±0.59 mg TE/g d.w., IC₅₀ =0.85±0.30 μg/mL, respectively), while G. resinaceum CHCl₃ extract was the most potent in NO assay (IC₅₀ =41.21±0.18-81.89±0.81 μg/mL). The highest TP and TS were generally determined in G. applanatum EtOH extracts. Enzyme inhibitory effects were determined in H₂ O extracts. Generally, CHCl₃ extracts showed the most powerful anti-inflammatory potential. These results suggest that analyzed species are a promising source of bioactive compounds and may be considered as candidates for new food supplements or drug formulations.

DFT Studies of Distinct Anilines with p-Hydroxycinnamic Acids for Antioxidant Profile

BACKGROUND

Life style and jobs in current situations have generated increased free radicals such as hydroxyl (OH•) and superoxide (O2•) radicals, thereby increasing stress in humans. Interest in search of antioxidants that trap these free radicals has increased to relieve stress. β-carotene (provitamin A), ascorbic acid (vitamin C), tocopherol or vitamin E, Trolox; butyl hydroxy toluene and phenolic compounds are the well-known antioxidants. Several methods evaluate the antioxidant property existing in natural substances (medicinal plants and agri-food products) and synthetic compounds (2-methyl-3- (pyrrolidin-2-ylideneamino) quinazolin-4 (3H) -one and 3,3'- (1,4- phenylenebis (methanylylidene)) bis (azanylylidene) (2-methyl-quinazolin-4 (3H) -one).

OBJECTIVE

The objective of this study is to focus on complexes with p-hydroxycinnamic acids to trap free radicals in a greener way.

METHODS

Spectroscopic shifts and structural studies were employed to attribute electronic properties responsible for antioxidant profile. Spectroscopic shifts in wavenumbers were attributed with Fourier Transform Infrared Spectra (FTIR) and Fourier Transform Raman spectra (FT Raman Spectra). Structural studies were performed with Gaussian package, electron density method the B3LYP method, basis set 6-31(d) for attributing electronic properties responsible for antioxidant profile.

RESULTS

Interpretation of FTIR spectra revealed spectroscopic shifts in wavenumbers in all the complexes responsible for bonding. Further, studies confirmed the formation of complex with reduced intensities in Raman spectra. Computational studies revealed enhancement in molecular and electronic properties responsible for antioxidant power.

CONCLUSION

Studies revealed that complex with p-nitroaniline contribute to greater acceptor and donor power responsible for antioxidant power. These higher powers suggest the best antiradicals to trap free radicals.

Efficacy of algal Ecklonia cava extract against viral hemorrhagic septicemia virus (VHSV)

The inhibition efficacy of an extract from Ecklonia cava (E. cava) was studied to determine whether the extract and compounds exhibited inhibitory activity against VHSV in the fathead minnow (FHM) cell line and following oral administration to the olive flounder. Based on its low toxicity and effective concentration, the E. cava extract (Ext) and compounds (eckol and phlorofucofuroeckol A) were selected for further analysis. In the plaque reduction assay, simultaneous co-exposure of VHSV to Ext, eckol and phlorofucofuroeckol A showed a higher level of inhibition than the pre- and post-exposure groups. The antiviral activity in the FHM cell line was time-dependent and increased with the exposure time with the virus and Ext or the compounds. In the in vivo experiments, different Ext concentrations were orally administered to the olive flounder. In trial I, the relative percent survival (RPS) following oral administration of 500 and 50 μg/g/day of Ext was 31.25% and 12.50%, respectively. In trial II, the RPS for 1000, 500 and 50 μg/g/day of Ext was 31.57%, 0% and 0%, respectively. In trial III, the RPS after 1 and 2 weeks (1000 μg/g/day) of exposure to Ext was 26.31% and 31.57%, respectively. Oral administration of Ext (1000 μg/g/day) significantly induced inflammatory cytokine responses (IL-1β, IL-6 and IFN-γ) at 1 and 2 days post-oral administration (dpa). Additionally, IFN-α/β (7-12 dpa), ISG15 (2, 7 and 10 dpa) and Mx (7-12 dpa) were significantly activated in the olive flounder. In conclusion, we demonstrated an inhibitory ability of the E. cava extract and compounds against VHSV in the FHM cell line. Moreover, oral administration of the E. cava extract to the olive flounder enhanced antiviral immune responses and the efficacy of protection against VHSV, resulting in an anti-viral status in the olive flounder.

Anti-stress activity of Sargassum polycystum extracts using a cold restraint stress model

Anti-stress effects of polyphenol extracts of Sargassum polycystum were evaluated. Polyphenol extracts of S. polycystum and diazepam were compared for anti-stress activities using a cold restraint animal stress model. S. polycystum extracts were administered orally at dosages of 150 and 450 mg/kg. Diazepam, an anti-stress agent, was used as a standard drug at 0.18 mg/kg p.o. Both dosages of S. polycystum extracts showed good anti-stress effects. Due to cold restraint stress there was an imbalance in levels of biochemical parameters, including glucose, triglycerides, cholesterol, alkaline phosphatase (ALP), alanine aminotransferase (ALT), and aspartate amino transferase (AST), which were near normalized following adminstration of S. polycystum extracts. Polyphenol extracts of S. polycystum at oral dosages of 150 and 450 mg/kg exerted anti-stress effects.

Antioxidant Effects of Brown Algae Sargassum on Sperm Parameters: CONSORT-Compliant Article

The occurrence of oxidative stress during the sperm freeze-thaw cycles affects the sperm parameters and eventually leads to a decrease in its reproductive potential. Sperm protection against oxidative reactions during freezing is done by antioxidants. Since the selection of a suitable sperm cryopreservation bank is effective in maintaining acceptable reproductive potential and motility of sperm during cryopreservation.This study aimed to evaluate the antioxidant effects of different doses of the extract of brown algae Sargassum on oxidative stress and frozen human sperm parameters.We conducted a randomized controlled trial on the semen samples from 11 healthy men in the age group of 25 to 36 years. The samples were collected by masturbation after 3 to 5 days of abstinence from ejaculation. The specimens were divided into 3 equal parts, including 1 control group and 2 experimental groups.The 2 experimental groups were frozen using the rapid solidification technique with Sargassum extract at doses of 250 and 500 μg/mL.Motility and morphology of sperms were measured using a computer system and CASA software and the amount of reactive oxygen species was determined using Oxisperm kit.Sargassum extract significantly decreased the amount of reactive oxygen species (P < 0.005) and at doses of 250 and 500 μg/mL, significantly increased the overall motility (P < 0.006) and progressive motility (P < 0.007) after solidification, but did not affect the normal morphology of sperms.The addition of ethanol extract of Sargassum prevents reactive oxygen species production during the solidification process and improves sperm motility at doses of 250 and 500 μg/mL.

In vitro antioxidant properties of crude extracts and compounds from brown algae

Research on the bioactives from seaweeds has increased in recent years. Antioxidant activity is one of the most studied, due to the interest of these compounds both as preservatives and protectors against oxidation in food and cosmetics and also due to their health implications, mainly in relation to their potential as functional ingredients. Brown algae present higher antioxidant potential in comparison with red and green families and contain compounds not found in terrestrial sources. In vitro antioxidant chemical methods, used as a first approach to evaluate potential agents to protect from lipid oxidation in foods, confirmed that the brown algae crude extracts, fractions and pure components are comparatively similar or superior to synthetic antioxidants. Particular emphasis on the fucoidan and phlorotannin polymeric fractions is given, considering variations associated with the species, collection area, season, and extraction and purification technologies.