Four sulfur-containing compounds with anti-colon cancer effect from marine-derived fungus Aspergillus terreus.

Sulfur-containing natural products possess a variety of biological functions including antitumor, antibacterial, anti-inflammatory and antiviral activities. In this study, four previously undescribed sulfur-containing compounds asperteretals L and M, terreins A and B, together with 17 known compounds were obtained from a culture of marine fungus A. terreus supplemented with inorganic sulfur source Na2SO4. Their planar structures and absolute configurations were elucidated by NMR, HRESIMS, and ECD experiments. The in vitro cytotoxicities of compounds 1-21 against HCT-116 and Caco-2 were evaluated by SRB assay. Asperteretal M (2) exhibited activity against HCT-116 with the IC50 value at 30µM. The antiproliferative effect of asperteretal M was confirmed by colony formation assay and cell death staining. Furthermore, the preliminary study on the anti-colon cancer mechanism of asperteretal M was performed by RNA-seq analysis. Western blotting validated that asperteretal M significantly decreased the expression of cell-cycle regulatory proteins CDK1, CDK4, and PCNA in a concentration-dependent manner.

Organosulfur Compounds in Colorectal Cancer Prevention and Progression.

This work represents an overview of the current investigations involving organosulfur compounds and colorectal cancer. The molecules discussed in this review have been investigated regarding their impact on colorectal cancer directly, at the in vitro, in vivo, and clinical stages. Organosulfur compounds may have indirect effects on colorectal cancer, such as due to their modulating effects on the intestinal microbiota or their positive effects on intestinal mucosal health. Here, we focus on their direct effects via the repression of multidrug resistance proteins, triggering of apoptosis (via the inhibition of histone deacetylases, increases in reactive oxygen species, p53 activation, ß-catenin inhibition, damage in the mitochondrial membrane, etc.), activation of TGF-ß, binding to tubulin, inhibition of angiogenesis and metastasis mechanisms, and inhibition of cancer stem cells, among others. In general, the interesting positive effects of these nutraceuticals in in vitro tests must be further analyzed with more in vivo models before conducting clinical trials.

Sulfur assimilation using gaseous carbonyl sulfide by the soil fungus Trichoderma harzianum.

Fungi have the capacity to assimilate a diverse range of both inorganic and organic sulfur compounds. It has been recognized that all sulfur sources taken up by fungi are in soluble forms. In this study, we present evidence that fungi can utilize gaseous carbonyl sulfide (COS) for the assimilation of a sulfur compound. We found that the filamentous fungus Trichoderma harzianum strain THIF08, which has constitutively high COS-degrading activity, was able to grow with COS as the sole sulfur source. Cultivation with 34S-labeled COS revealed that sulfur atom from COS was incorporated into intracellular metabolites such as glutathione and ergothioneine. COS degradation by strain THIF08, in which as much of the moisture derived from the agar medium as possible was removed, indicated that gaseous COS was taken up directly into the cell. Escherichia coli transformed with a COS hydrolase (COSase) gene, which is clade D of the ß-class carbonic anhydrase subfamily enzyme with high specificity for COS but low activity for CO2 hydration, showed that the COSase is involved in COS assimilation. Comparison of sulfur metabolites of strain THIF08 revealed a higher relative abundance of reduced sulfur compounds under the COS-supplemented condition than the sulfate-supplemented condition, suggesting that sulfur assimilation is more energetically efficient with COS than with sulfate because there is no redox change of sulfur. Phylogenetic analysis of the genes encoding COSase, which are distributed in a wide range of fungal taxa, suggests that the common ancestor of Ascomycota, Basidiomycota, and Mucoromycota acquired COSase at about 790-670 Ma.IMPORTANCEThe biological assimilation of gaseous CO2 and N2 involves essential processes known as carbon fixation and nitrogen fixation, respectively. In this study, we found that the fungus Trichoderma harzianum strain THIF08 can grow with gaseous carbonyl sulfide (COS), the most abundant and ubiquitous gaseous sulfur compound, as a sulfur source. When the fungus grew in these conditions, COS was assimilated into sulfur metabolites, and the key enzyme of this assimilation process is COS hydrolase (COSase), which specifically degrades COS. Moreover, the pathway was more energy efficient than the typical sulfate assimilation pathway. COSase genes are widely distributed in Ascomycota, Basidiomycota, and Mucoromycota and also occur in some Chytridiomycota, indicating that COS assimilation is widespread in fungi. Phylogenetic analysis of these genes revealed that the acquisition of COSase in filamentous fungi was estimated to have occurred at about 790-670 Ma, around the time that filamentous fungi transitioned to a terrestrial environment.

Preliminary investigation of a combined herbal extract of Aruncus dioicus, Cirsium nipponicum, and Ocimum basilicum for halitosis.

BACKGROUND: Halitosis, the unpleasant odor in the oral cavity, has garnered increased attention and concern due to the growing significance of social interaction. SGE-107, a blend of 3 botanical drugs-Korean goat's beard, Cirsium tanakae, and Basil-with caffeic acid as its indicator component. This study aims to investigate the efficacy of SGE-107 in treating halitosis in patients with mild gastrointestinal symptoms. METHODS: We enrolled 25 participants with oral malodor and dyspeptic symptoms. We assessed the severity of halitosis using the visual analog scale. Throughout a 4-week period of administering SGE-107, we evaluated both objective and subjective parameters, including the halitosis-associated life-quality test, the Korean gastrointestinal symptom rating scale, levels of volatile sulfur compounds, salivary flow rate, oral moisture, tongue index, Winkel tongue coating index, and tongue temperature. RESULTS: After the intervention period, both the visual analog scale (5.88 ±â€…1.03 vs 2.38 ±â€…0.93, P < .001) and the scores of the halitosis-associated life-quality test (31.21 ±â€…11.78 vs 13.83 ±â€…6.38, P < .001) showed significant reductions. The proportion of participants with abnormal levels of methyl mercaptan (a volatile sulfur compound) also significantly decreased (17, 70.8% vs 9, 37.5%, P = .039). Furthermore, there were significant improvements in reflux, constipation, diarrhea, and the total scores on the Korean gastrointestinal symptom rating scale. Throughout the study period, only 2 participants experienced mild adverse events. CONCLUSION: SGE-107 appears to be a safe and effective treatment for halitosis-associated with gastrointestinal symptoms; nevertheless, the limited sample size necessitates further large-scale randomized, controlled studies to confirm our findings.

Release characteristics and risk assessment of volatile sulfur compounds in a municipal wastewater treatment plant with odor collection device.

Due to the malodorous effects and health risks of volatile sulfur compounds (VSCs) emitted from wastewater treatment plants (WWTPs), odor collection devices have been extensively utilized; however, their effectiveness has rarely been tested. In the present investigation, the characteristics of VSCs released in a WWTP equipped with gas collection hoods are methodically examined by gas chromatography. The obtained results indicate that the concentration of VSCs in the ambient air can be substantially reduced, and the primary treatment unit still achieves the highest concentration of VSCs. Compared to WWTPs without odor collection devices, the concentration of H2S in this WWTP is not dominant, but its sensory effects and health risks are still not negligible. Additionally, research on the emission of VSCs from sludge reveals that the total VSCs emitted from dewatering sludge reaches the highest level. Volatile organic sulfur compounds play a dominant role in the component and sensory effects of VSCs released by sludge. This study provides both data and theoretical support for analyzing the effectiveness of odor collection devices in WWTPs, as well as reducing the source of VSCs. The findings can be effectively employed to optimize these devices and improve their performance.

[Development of Functional Compounds Using Chemically Unstable Compounds Obtained from Medicinal Plants].

Sulfur- or nitrogen-containing compounds from medicinal plants exhibit various biological activities such as anticancer potential. Developing efficient strategies to isolate or synthesize these compounds or their derivatives is a remarkable achievement. We have isolated several sulfur-containing compounds such as tetrahydro-2H-difuro[3,2-b:2',3'-c]furan-5(5aH)-one derivatives from Allium plants. We have devised a unique approach for the rapid preparation of thiopyranones using the regioselective sequential double Diels-Alder reaction; we used a naturally-occurring chemically-unstable intermediate such as thioacrolein, which is produced from allicin, a major component in garlic. The cytotoxicity of the synthetic thiopyranones against cancer stem cells (CSCs) was equal to or higher than that of (Z)-ajoene, the reference compound.

Development of an analytic method for organosulfur compounds in Welsh onion and its use for nutritional quality analysis of five typical varieties in China.

A reliable, simple, and sensitive method capable of quantifying six organosulfur compounds (OSCs) was established. The samples were extracted by water containing 3 % formic acid with a simple vortex, ultrasound, and centrifugation step, and the solutions were analyzed by ultra-high-performance liquid chromatography separation system coupled with a triple-quadrupole mass spectrometry (UHPLC - MS/MS). Then the method was applied for the analysis of six OSCs in five varieties of two types Welsh onions in China, and the moisture content, reducing sugar, total polyphenols, and 21 free amino acids were also analyzed to study the characters of these Welsh onions intensively. Multivariate statistical analysis was used to investigate the differences in OSCs and free amino acids profiles among the samples. This study showed that enzymatic inhibition method combined with UHPLC - MS/MS is an effective technique to analyze OSCs in Welsh onion, and could be valuable for the routine quantitation of OSCs in other foods.

Diverse pollen nutrition can improve the development of solitary bees but does not mitigate negative pesticide impacts.

Floral resource loss and pesticide exposure are major threats to bees in intensively managed agroecosystems, but interactions among these drivers remain poorly understood. Altered composition and lowered diversity of pollen nutrition may reinforce negative pesticide impacts on bees. Here we investigated the development and survival of the solitary bee Osmia bicornis provisioned with three different pollen types, as well as a mixture of these types representing a higher pollen diversity. We exposed bees of each nutritional treatment to five pesticides at different concentrations in the laboratory. Two field-realistic concentrations of three nicotinic acetylcholine receptor (nAChR) modulating insecticides (thiacloprid, sulfoxaflor and flupyradifurone), as well as of two fungicides (azoxystrobin and tebuconazole) were examined. We further measured the expression of two detoxification genes (CYP9BU1, CYP9BU2) under exposure to thiacloprid across different nutrition treatments as a potential mechanistic pathway driving pesticide-nutrition interactions. We found that more diverse pollen nutrition reduced development time, enhanced pollen efficacy (cocoon weight divided by consumed pollen weight) and pollen consumption, and increased weight of O. bicornis after larval development (cocoon weight). Contrary to fungicides, high field-realistic concentrations of all three insecticides negatively affected O. bicornis by extending development times. Moreover, sulfoxaflor and flupyradifurone also reduced pollen efficacy and cocoon weight, and sulfoxaflor reduced pollen consumption and increased mortality. The expression of detoxification genes differed across pollen nutrition types, but was not enhanced after exposure to thiacloprid. Our findings highlight that lowered diversity of pollen nutrition and high field-realistic exposure to nAChR modulating insecticides negatively affected the development of O. bicornis, but we found no mitigation of negative pesticide impacts through increased pollen diversity. These results have important implications for risk assessment for bee pollinators, indicating that negative effects of nAChR modulating insecticides to developing solitary bees are currently underestimated.

Comprehensive metabolite and biological profile of "Sulmona Red Garlic" ecotype's aerial bulbils.

"Sulmona Red Garlic" is a well-known Italian traditional product. Bulbs, used for culinary purposes, have been largely investigated for their medicinal properties whereas aerial bulbils are usually removed as waste material. Here, for the first time, chemical composition and biological properties of the hydroalcoholic extract from aerial bulbils were investigated. Complementary information on metabolite composition were obtained using both NMR based untargeted and HPLC-DAD targeted methodologies. The NMR analysis revealed the presence of sugars, organic acids, amino acids, organosulphur compounds (methiin, alliin, allicin and cycloalliin), and other secondary metabolites. In particular, methiin and alliin were identified for the first time in the NMR spectra of aerial bulbil garlic extracts. Polyphenol content was determined by HPLC-DAD analysis: catechin, chlorogenic acid, and gallic acid turned out to be the most abundant phenolics. Hydroalcoholic extract blocked cell proliferation of colon cancer cell line HCT116 with an IC50 of 352.07 µg/mL, while it was non-toxic to myoblast cell line C2C12. In addition, it caused seedling germination reduction of two edible and herbaceous dicotyledon species, namely Cichorium intybus and C. endivia. Moreover, the same extract reduced the gene expression of TNF-α (tumor necrosis factor), HIF1-α (hypoxia-inducible factor), VEGFA (vascular endothelial growth factor), and transient receptor potential (TRP) M8 (TRPM8) indicating the ability to contrast cancer development through the angiogenic pathway. Final, in silico experiments were also carried out supporting the biological effects of organosulphur compounds, particularly alliin, which may directly interact with TRPM8. The results here reported suggest the potential use of garlic aerial bulbils often considered a waste product as a source in phytotherapeutic remedies.

Optimization of complex coacervation parameters for the production of encapsulated black garlic using response surface methodology.

The purpose of this study was to optimize black garlic encapsulation parameters (core/coating ratio, extract concentration, and coacervate/maltodextrin [MD] ratio) using central composite design of the response surface methodology based on encapsulation efficiency (EE) (%). The optimum parameters were determined as 4.0 for the coating material/core ratio, 50% for the extract concentration, and 6.0 for the MD/coacervate ratio depending on the EE (%). The antioxidant activity values were determined as 101 and 134 µmol Trolox/100 g dry weight (DW) for the 2,2-diphenyl-1-picrylhydrazyl and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) methods, respectively, whereas the total phenolic content was 49 mg gallic acid equivalent/100 g DW for the encapsulated black garlic samples. S-Allyl-l-cysteine (SAC), γ-l-glutamyl-SAC (GSAC), γ-l-glutamyl-(S)-trans-1-propenyl-l-cysteine, and allicin were the organosulfur (OS) compounds determined in the samples. The SAC concentration of the encapsulated black garlic samples was determined as 22.36 mg/g, whereas the GSAC content was found at a lower concentration (0.33 mg/g) compared to SAC. The allicin content was quantified to be 0.31 mg/g. The encapsulated samples were also characterized by scanning electron microscopy (SEM) and Fourier transform infrared (FT-IR) spectroscopy. The FT-IR analysis revealed specific functional groups, including hydroxyl, carbonyl, and glycosidic linkage. The interaction between lentil protein isolate and pectin was strong enough to encourage capsule formation as visualized in the SEM images. This study shows the potential of black garlic coacervates as a functional ingredient for the food industry due to their stability, solubility, and preservation of OS and antioxidant compounds.

Searching for bacteria able to metabolize polycyclic aromatic sulfur compounds in 12-years periodically fed bioreactor.

Biodesulfurization is a promising alternative for removing sulfur molecules from the polycyclic aromatic sulfur compounds (PASC) found in petroleum. PASC consists of recalcitrant molecules that can degrade fuel quality and cause a range of health and environmental problems. Therefore, identifying bacteria capable of degrading PASC is essential for handling these recalcitrant molecules. Microorganisms in environments exposed to petroleum derivatives have evolved specific enzymatic machinery, such as the 4S pathway associated with the dszABC genes, which are directly linked to sulfur removal and utilization as nutrient sources in the biodesulfurization process. In this study, bacteria were isolated from a bioreactor containing landfarm soil that had been periodically fed with petroleum for 12 years, using a medium containing dibenzothiophene (DBT), 4.6-dimethylbenzothiophene, 4-methylbenzothiophene, or benzothiophene. This study aimed to identify microorganisms capable of degrading PASC in such environments. Among the 20 colonies isolated from an inoculum containing DBT as the sole sulfur source, only four isolates exhibited amplification of the dszA gene in the dszABC operon. The production of 2-hydroxybiphenyl (HPB) and a decrease in DBT were detected during the growth curve and resting cell assays. The isolates were identified using 16S rRNA sequencing belonging to the genera Stutzerimonas and Pseudomonas. These isolates demonstrated significant potential for biodesulfurization and/or degradation of PASC. All isolates possessed the potential to be utilized in the biotechnological processes of biodesulfurization and degradation of recalcitrant PASC molecules.

Effect of Yogurt and Its Components on the Deodorization of Raw and Fried Garlic Volatiles.

Garlic contains sulfur volatiles that cause a bad odor after consumption. The objective of this study was to understand how yogurt and its components cause deodorization. Raw and fried garlic samples were mixed with various treatments and measurements of volatiles were conducted using a selected-ion flow-tube mass spectrometer. Frying garlic significantly reduced almost all sulfur volatile compounds. Raw garlic was deodorized more than fried garlic by all of the treatments. Fat, protein and water significantly reduced the concentration of sulfur-based volatiles in garlic. At the same concentration, either fat or protein produced higher deodorization, depending on the hydrophobicity of the volatile. Whey protein, casein and their complex all caused deodorization. Increasing the pH to 7 or heating changed the structure of the proteins and decreased the deodorization of the volatiles, showing the importance of proteins for deodorization. As the quantity of fat increased, the deodorization of the volatiles also increased. Foods with higher fat or protein content can be formulated to offer a potential solution to reduce the unpleasant odor associated with garlic consumption.

The Garlic Tree of Borneo, Scorodocarpus borneensis (Baill.) Becc. (Olacaceae): Potential Utilization in Pharmaceutical, Nutraceutical, and Functional Cosmetic Industries.

Scorodocarpus borneensis (Baill.) Becc. is attracting increased attention as a potential commercial medicinal plant product in Southeast Asia. This review summarizes the current knowledge on the taxonomy, habitat, distribution, medicinal uses, natural products, pharmacology, toxicology, and potential utilization of S. borneesis in the pharmaceutical/nutraceutical/functional cosmetic industries. All data in this review were compiled from Google Scholar, PubMed, Science Direct, Web of Science, ChemSpider, PubChem, and a library search from 1866 to 2022. A total of 33 natural products have been identified, of which 11 were organosulfur compounds. The main organosulfur compound in the seeds is bis-(methylthiomethyl)disulfide, which inhibited the growth of a broad spectrum of bacteria and fungi, T-lymphoblastic leukemia cells, as well as platelet aggregation. Organic extracts evoked anti-microbial, cytotoxic, anti-free radical, and termiticidal effects. S. borneensis and its natural products have important and potentially patentable pharmacological properties. In particular, the seeds have the potential to be used as a source of food preservatives, antiseptics, or termiticides. However, there is a need to establish acute and chronic toxicity, to examine in vivo pharmacological effects and to perform clinical studies.

Novel Cytotoxic Sesquiterpene Coumarin Ethers and Sulfur-Containing Compounds from the Roots of Ferula turcica.

Six new sesquiterpene coumarin ethers, namely turcicanol A (1), turcicanol A acetate (2), turcicanol B (3), turcica ketone (4), 11'-dehydrokaratavicinol (5), and galbanaldehyde (6), and one new sulfur-containing compound, namely turcicasulphide (7), along with thirty-two known secondary metabolites were isolated from the root of the endemic species Ferula turcica Akalin, Miski, & Tuncay through a bioassay-guided isolation approach. The structures of the new compounds were elucidated by spectroscopic analysis and comparison with the literature. Cell growth inhibition of colon cancer cell lines (COLO205 and HCT116) and kidney cancer cell lines (UO31 and A498) was used to guide isolation. Seventeen of the compounds showed significant activity against the cell lines.

Potential antitumor activity of garlic against colorectal cancer: focus on the molecular mechanisms of action.

PURPOSE: The aim of this review is to highlight the potential of garlic phytoconstituents as antitumor agents in colorectal cancer management based on their molecular mechanisms of action, while asking if their consumption, as part of the human diet, might contribute to the prevention of colorectal cancer. METHODS: To gather information on appropriate in vitro, in vivo and human observational studies on this topic, the keywords "Allium sativum", "garlic", "colorectal cancer", "antitumor effect", "in vitro", "in vivo", "garlic consumption" and "colorectal cancer risk" were searched in different combinations in the international databases ScienceDirect, PubMed and Google Scholar. After duplicate and reviews removal, 61 research articles and meta-analyses published between 2000 and 2022 in peer-reviewed journals were found and included in this review. RESULTS: Garlic (Allium sativum) proves to be a rich source of compounds with antitumor potential. Garlic-derived extracts and several of its individual constituents, especially organosulfur compounds such as allicin, diallyl sulfide, diallyl disulfide, diallyl trisulfide, diallyl tetrasulfide, allylmethylsulfide, S-allylmercaptocysteine, Z-ajoene, thiacremonone and Se-methyl-L-selenocysteine were found to possess cytotoxic, cytostatic, antiangiogenic and antimetastatic activities in different in vitro and in vivo models of colorectal cancer. The molecular mechanisms for their antitumor effects are associated with the modulation of several well-known signaling pathways involved in cell cycle progression, especially G1-S and G2-M transitions, as well as both the intrinsic and extrinsic apoptotic pathways. However, even though in various animal models some of these compounds have chemopreventive effects, based on different human observational studies, a diet rich in garlic is not consistently associated with a lower risk of developing colorectal cancer. CONCLUSION: Independent of the impact of garlic consumption on colorectal cancer initiation and promotion in humans, its constituents might be good candidates for future conventional and/or complementary therapies, based on their diverse mechanisms of action.

Urinary excretion of organosulfur compounds after acute ingestion of black onion.

Onion (Allium cepa L.) and its newly derived product "black onion" are characterised by the presence of compounds with potential bioactivity, particularly organosulfur compounds (OSCs). However, little is known about the metabolism, distribution, and excretion of these compounds as they pass through the gastrointestinal tract. This study monitored healthy subjects after an acute intake of black onion and analysed the excretion of OSCs using UHPLC-HRMS. A total of 31 OSCs were detected in urine after the acute ingestion of black onion, the main components being S-methyl-L-cysteine sulfoxide (methiin) (13.6 ± 3.9 µmol), isoalliin (12.4 ± 4.7 µmol) and S-propyl-L-cysteine (deoxypropiin) (3.1 ± 0.7 µmol). Moreover, N-acetylated metabolites of the major OSCs detected in black onion, namely, N-acetyl-S-(1-propenyl)-L-cysteine sulfoxide (NAS1PCS) and N-acetyl-S-(1-propenyl)-L-cysteine (NAS1PC), were found in urine after black onion consumption. The N-acetylation reaction takes place in the kidneys and liver, and metabolism pathways are proposed to explain the excretion of OSCs in urine. The basis of the identification of OSCs as urinary metabolites after black onion consumption is described for the first time and provides the basis for further research.

Organosulfur Compounds of Allium Subgenus Nectaroscordum Species.

Organosulfur compounds formed upon comminuting the bulbs of two Allium subgenus Nectaroscordum species (Allium siculum and Allium tripedale) were analyzed by HPLC-PDA-MS/MS. The major organosulfur components were isolated and structurally characterized (MS, NMR), including several previously unknown compounds. It was found that the organosulfur chemistry occurring when these plants are cut is very similar to that observed in onion (Allium cepa). In all cases, however, the organosulfur compounds found in Nectaroscordum species were higher homologues of those observed in onion, being formed by various combinations of C1 and C4 building blocks derived from methiin and homoisoalliin/butiin, respectively. Thiosulfinates, bis-sulfine, cepaenes, and several cepaene-like compounds were identified among the major organosulfur components present in the homogenized bulbs. Several groups of 3,4-diethylthiolane-based compounds, structurally homologous with onionin A, cepathiolane A, allithiolanes A-H, and cepadithiolactone A, found in onion, were also detected.

Optimization of Biodesulfurization of sour heavy crude oil.

Biodesulfurization of fossil fuels is a promising method for treating the sour oil due to its environmental friendliness and ability to get rid of the recalcitrant organosulfur compounds. In this study, many types of microorganisms such as Ralstonia eutropha, Rhodococcus erythropolis, Acidithiobacillus ferrooxidans, and Acidithiobacillus thiooxidans applied on a sour heavy crude oil (sulfur content was 4.4%). Also, a colony isolated from the crude oil and oil concentrate was examined by supplying it with PTCC 106. The various official and famous mediums were significantly evaluated such as (PTCC 2, PTCC 105, PTCC 106 (9K), PTCC 116, PTCC 123, PTCC 132), sulfur-free MG-medium, basal salts medium, and mineral salts. It was found that Rhodococcus erythropolis and Acidithiobacillus ferrooxidans from microorganisms and SFM and the medium PTCC 105 were selected as the higher desulfurization efficiencies of crude oil equaling 47 and 19.74% respectively. The bioreactions depend on the treated fluid, targeting sulfur compounds as these represent the environmental status (amounts and types of nutrients), and the type of biotreaters whether microorganism are septic, semiseptic, or aseptic. The optimum operation conditions have been designed by using Definitive method such as mixing speed, temperature, surfactant dose, OWR, acidity. The optimum efficiencies obtained here are better than the previous efforts even though those gained by bioengineering. Biodesalination was a simultaneous process with the BDS.

Improving endothelial health with food-derived H2S donors: an in vitro study with S-allyl cysteine and with a black-garlic extract enriched in sulfur-containing compounds.

A healthy vascular endothelium plays an essential role in modulating vascular tone by producing and releasing vasoactive factors such as nitric oxide (NO). Endothelial dysfunction (ED), the loss of the endothelium physiological functions, results in the inability to properly regulate vascular tone, leading to hypertension and other cardiovascular risk factors. Alongside NO, the gasotransmitter hydrogen sulfide (H2S) has emerged as a key molecule with vasodilatory and antioxidant activities. Since a reduction in H2S bioavailability is related to ED pathogenesis, natural H2S donors are very attractive. In particular, we focused on the sulfur-containing amino acid S-allyl cysteine (SAC), a bioactive metabolite, of which black garlic is particularly rich, with antioxidant activity and, among others, anti-diabetic and anti-hypertensive properties. In this study, we analyzed the protective effect of SAC against ED by evaluating reactive oxygen species level, H2S release, eNOS phosphorylation, and NO production (by fluorescence imaging and western blot analysis) in Bovine Aortic Endothelial cells (BAE-1). Furthermore, we chemically characterized a Black Garlic Extract (BGE) for its content in SAC and other sulfur-containing amino acids. BGE was used to carry out an analysis on H2S release on BAE-1 cells. Our results show that both SAC and BGE significantly increase H2S release. Moreover, SAC reduces ROS production and enhances eNOS phosphorylation and the consequent NO release in our cellular model. In this scenario, a natural extract enriched in SAC could represent a novel therapeutic approach to prevent the onset of ED-related diseases.

Bio-catalytic degradation of dibenzothiophene (DBT) in petroleum distillate (diesel) by Pseudomonas spp.

Biodesulfurization (BDS) was employed in this study to degrade dibenzothiophene (DBT) which accounts for 70% of the sulfur compounds in diesel using a synthetic and typical South African diesel in the aqueous and biphasic medium. Two Pseudomonas sp. bacteria namely Pseudomonas aeruginosa and Pseudomonas putida were used as biocatalysts. The desulfurization pathways of DBT by the two bacteria were determined by gas chromatography (GC)/mass spectrometry (MS) and High-Performance Liquid Chromatography (HPLC). Both organisms were found to produce 2-hydroxy biphenyl, the desulfurized product of DBT. Results showed BDS performance of 67.53% and 50.02%, by Pseudomonas aeruginosa and Pseudomonas putida, respectively for 500 ppm initial DBT concentration. In order to study the desulfurization of diesel oils obtained from an oil refinery, resting cells studies by Pseudomonas aeruginosa were carried out which showed a decrease of about 30% and 70.54% DBT removal for 5200 ppm in hydrodesulfurization (HDS) feed diesel and 120 ppm in HDS outlet diesel, respectively. Pseudomonas aeruginosa and Pseudomonas putida selectively degraded DBT to form 2-HBP. Application of these bacteria for the desulfurization of diesel showed promising potential for decreasing the sulfur content of South African diesel oil.