Organosulfide profile and hydrogen sulfide-releasing capacity of stinky bean (Parkia speciosa) oil: Effects of pH and extraction methods

Effect of Boiling, Steaming and Microwaving on the Antioxidant and Antibacterial Properties of Parkia speciosa Seeds

This study investigated the effects of boiling, steaming, and microwaving on the total phenolic content (TPC), cyclic polysulfide content, antioxidant, and antibacterial properties of Parkia speciosa seeds. Ferric reducing antioxidant power (FRAP) and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging activity of the seeds were evaluated. The main antibacterial components of P. speciosa seeds, cyclic polysulfides were characterized using Gas Chromatography-Mass Spectrometry analysis and evaluated using a broth microdilution method against seven gram-positive and five gram-negative bacterial strains. Microwaving displayed the highest decrease in TPC, followed by boiling, while steaming retained most TPC. Thermal treatment did not affect DPPH free radical scavenging activity but significantly reduced the FRAP of the seeds. Uncooked seeds exhibited significant antibacterial activity against the 12 bacterial strains with minimum inhibitory concentration (MIC) values of 5-40 mg/mL. Thermal treatment of the seeds displayed reduced antibacterial activity, a decreased amount of 1,2,4,5-tetrathiane whereas 1,3,5-trithiane and 1,2,5,6-tetrathiocane were detected.

Organosulfur in food samples: Recent updates on sampling, pretreatment and determination technologies

Organosulfur compounds (OSCs), mainly found in garlic, are the main biologically active substances for their pharmacological effects, including lowering of blood pressure and cholesterol, anti-cancer effect, liver protection, and anti-inflammatory. Efficient and sensitive pretreatment and determination methods of OSCs in different food matrices are of great significance. This review provides a comprehensive summary about the pretreatment and determination methods for OSCs in different food samples since 2010. Commonly used pretreatment methods, such as liquid-liquid extraction, microwave-assisted extraction, pressurized liquid extraction, liquid-liquid microextraction, solid phase extraction, dispersive solid phase extraction, solid-phase microextraction, and so on, have been summarized and overviewed in this paper. In particular, we discussed and compared various analysis methods including high performance liquid chromatography coupled with different detectors, gas chromatography-based methods, and few other methods. Finally, we tried to highlight the applicability, advantages and disadvantages of different pretreatment and analysis methods, and identified future prospects in this field.

Progress and perspective on hydrogen sulfide donors and their biomedical applications

Following the discovery of nitric oxide (NO) and carbon monoxide (CO), hydrogen sulfide (H₂ S) has been identified as the third gasotransmitter in humans. Increasing evidence have shown that H₂ S is of preventive or therapeutic effects on diverse pathological complications. As a consequence, it is of great significance to develop suitable approaches of H₂ S-based therapeutics for biomedical applications. H₂ S-releasing agents (H₂ S donors) play important roles in exploring and understanding the physiological functions of H₂ S. More importantly, accumulating studies have validated the theranostic potential of H₂ S donors in extensive repertoires of in vitro and in vivo disease models. Thus, it is imperative to summarize and update the literatures in this field. In this review, first, the background of H₂ S on its chemical and biological aspects is concisely introduced. Second, the studies regarding the H₂ S-releasing compounds are categorized and described, and accordingly, their H₂ S-donating mechanisms, biological applications, and therapeutic values are also comprehensively delineated and discussed. Necessary comparisons between related H₂ S donors are presented, and the drawbacks of many typical H₂ S donors are analyzed and revealed. Finally, several critical challenges encountered in the development of multifunctional H₂ S donors are discussed, and the direction of their future development as well as their biomedical applications is proposed. We expect that this review will reach extensive audiences across multiple disciplines and promote the innovation of H₂ S biomedicine.

Near-Infrared Fluorescent Probe with a Large Stokes Shift for Detection of Hydrogen Sulfide in Food Spoilage, Living Cells, and Zebrafish

Hydrogen sulfide (H₂S) is a significant component of various physiological processes, and it can also cause a negative effect on foodstuffs. In this work, we designed and synthesized an NIR fluorescent turn-on responding probe (DDM-H₂S) with a large Stokes shift (190 nm) for the detection of H₂S. DDM-H₂S exhibited high selectivity and sensitivity, obvious color changes, and a fast response time for tracing H₂S. When DDM-H₂S reacted with H₂S, the PET process was eliminated, and the recovered ICT process and NIR fluorescence were observed. Moreover, DDM-H₂S could image endogenous and exogenous H₂S in living HeLa cells and zebrafish. What is more, the probe DDM-H₂S could be deposited easily to test paper strips, which were able to detect the H₂S gas produced during food spoilage (such as eggs, raw meat, and fishes) by the color of test paper strips changing from pink to purple. Therefore, this work provides a promising approach for monitoring H₂S in complicated biological systems and practical food samples.

Phytochemical Contents and Pharmacological Potential of Parkia speciosa Hassk. for Diabetic Vasculopathy: A Review

Diabetes mellitus (DM) is a metabolic disorder characterized by hyperglycemia and is considered a major health problem in the world. It is associated with endothelial dysfunction which causes progressive vascular damage. DM is a known risk factor for atherosclerosis and cardiovascular complications such as peripheral artery disease, coronary artery disease, and stroke. Medicinal plants may act as an alternative resource or adjunctive treatment option in the treatment of diabetes and its cardiovascular complications. Parkia speciosa (Fabaceae) is a plant found abundantly in the Southeast Asian region. Its seeds, with or without pods, and roots have long been used as a traditional medicine in this region to treat hypertension and diabetes. Studies have shown its numerous beneficial pharmacological properties. Extracts of P. speciosa, particularly from its seeds and empty pods, show the presence of polyphenols. They also exhibit potent antioxidant, hypoglycemic, anti-inflammatory, and antihypertensive properties. Its hypoglycemic properties are reported to be associated with the presence of β-sitosterol, stigmasterol, and stigmat-4-en-3-one. The current review aimed to provide an overview of the current status of P. speciosa, its pharmacological potential, and its phytochemical content in attenuating diabetic vasculopathy. Glycemic status, oxidative stress, inflammation, and hyperlipidemia are known to play pivotal roles in the initiation and severity of diabetic cardiovascular diseases; thus, targeting these factors might be beneficial for preventing and/or treating diabetic vasculopathy.

Dietary Organosulfur-Containing Compounds and Their Health-Promotion Mechanisms

Dietary organosulfur-containing compounds (DOSCs) in fruits, vegetables, and edible mushrooms may hold the key to the health-promotion benefits of these foods. Yet their action mechanisms are not clear, partially due to their high reactivity, which leads to the formation of complex compounds during postharvest processing. Among postharvest processing methods, thermal treatment is the most common way to process these edible plants rich in DOSCs, which undergo complex degradation pathways with the generation of numerous derivatives over a short time. At low temperatures, DOSCs are biotransformed slowly during fermentation to different metabolites (e.g., thiols, sulfides, peptides), whose distinctive biological activity remains largely unexplored. In this review, we discuss the bioavailability of DOSCs in human digestion before illustrating their potential mechanisms for health promotion related to cardiovascular health, cancer chemoprevention, and anti-inflammatory and antimicrobial activities. In particular, it is interesting that different DOSCs react with glutathione or cysteine, leading to the slow release of hydrogen sulfide (H2S), which has broad bioactivity in chronic disease prevention. In addition, DOSCs may interact with protein thiol groups of different protein targets of importance related to inflammation and phase II enzyme upregulation, among other action pathways critical for health promotion.

Expected final online publication date for the Annual Review of Food Science and Technology, Volume 13 is March 2022. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Diet and Hydrogen Sulfide Production in Mammals

Significance: In recent times, it has emerged that some dietary sulfur compounds can act on mammalian cell signaling systems via their propensity to release hydrogen sulfide (H₂S). H₂S plays important biochemical and physiological roles in the heart, gastrointestinal tract, brain, kidney, and immune systems of mammals. Reduced levels of H₂S in cells and tissues correlate with a spectrum of pathophysiological conditions, including heart disease, diabetes, obesity, and altered immune function. Recent Advances: In the last decade, researchers have now begun to explore the mechanisms by which dietary-derived sulfur compounds, in addition to cysteine, can act as sources of H₂S. This research has led to the identified several compounds, organic sulfides, isothiocyanates, and inorganic sulfur species including sulfate that can act as potential sources of H₂S in mammalian cells and tissues. Critical Issues: We have summarised progress made in the identification of dietary factors that can impact on endogenous H₂S levels in mammals. We also describe current research focused on how some sulfur molecules present in dietary plants, and associated chemical analogues, act as sources of H₂S, and discuss the biological properties of these molecules as studied in a range of in vitro and in vivo systems. Future Directions: The identification of sulfur compounds in edible plants that can act as novel H₂S releasing molecules is intriguing. Research in this area could inform future studies exploring the impact of diet on H₂S levels in mammalian systems. Despite recent progress, additional work is needed to determine the mechanisms by which H₂S is released from these molecules following ingestions of dietary plants in humans, whether the amounts of H₂S produced is of physiological significance following the metabolism of these compounds in vivo, and if diet could be used to manipulated H₂S levels in humans. Importantly, this will lead to a better understanding of the biological significance of H₂S generated from dietary sources, and this information could be used in the development of plant breeding initiatives to increase the levels of H₂S releasing sulfur compounds in crops, or inform dietary intervention strategies that could be used to alter the levels of H₂S in humans.

Microwave Drying for Production of Rehydrated Foods: A Case Study of Stink Bean (Parkia speciosa) Seed

The potential of microwave drying in the production of rehydrated foods is demonstrated with stink beans (Parkia speciosa), smelly legumes of Africa and Asia. Compared to stink beans dehydrated by convective drying and freeze drying, the microwave products exhibit higher moisture contents, but the distribution of microscopic pores leads to good rehydration characteristics. Dehydration by microwave drying is also achieved within a much shorter period than that commonly used in freeze drying. The dehydration time can be further reduced to 6 h comparable to convective drying, and the moisture content is dropped to 11% by decreasing the pressure during microwave drying. However, the rehydration time remains around 65 min for products from both ambient and low-pressure (400 Pa) microwave drying. In rehydration, the period is successfully reduced to 30 min by increasing the water temperature to 70 °C. The results indicate that microwave drying does not affect the value of crude protein and rehydrated products are comparable to fresh stink beans. From these findings, the microwave drying technique is an applicable technology for both manufacturers and consumers, with acceptable drying time and rehydration characteristics.

Genus Parkia: Phytochemical, Medicinal Uses, and Pharmacological Properties

The genus Parkia (Fabaceae, Subfamily, Mimosoideae) comprises about 34 species of mostly evergreen trees widely distributed across neotropics, Asia, and Africa. This review aims to provide an overview of the current status of the species from the genus Parkia in terms of its relationship between its phytochemistry and medical uses. Comprehensive information on Parkia species was retrieved from electronic databases, which were Web of Science, ScienceDirect, PubMed, and Google Scholar. This review identified nine species from genus Parkia with properties of medicinal use. They are used traditionally to treat several ailments, such as diabetes, diarrhea, wounds, hypertension, cough, chronic piles, conjunctivitis, and measles. The most common species studied are P. biglobosa, P. speciosa, P. javanica, P. bicolor, P. biglandulosa, P. filicoidea, and P. clappertoniana. A considerable number of secondary metabolites, such as terpenoids, phenolic acids, flavonoids (aglycone and glycosides), and numerous volatile compounds have been identified in this genus, which are responsible for their diverse pharmacological activities. Their extracts, pure compounds and seed lectins have been reported for their anticancer, antimicrobial, antihypertensive, antiulcer, antidiabetic, anti-inflammatory, antioxidant, antimalarial, hepatoprotective, and antidiarrheal activities. The information gathered in this review might be of help for future studies in terms of the current knowledge on the link between the phytochemical components and medicinal uses. This could facilitate more discoveries on its potentials particularly in the pharmacological characteristics and potential to be developed into modern medicines.

Garlic and Gaseous Mediators

Garlic (Allium sativum) and allied plant species are rich sources of sulfur compounds. Major roles for garlic and its sulfur constituents include the regulation of vascular homeostasis and the control of metabolic systems linked to nutrient metabolism. Recent studies have indicated that some of these sulfur compounds, such as diallyl trisulfide (DATS), alter the levels of gaseous signalling molecules including nitric oxide (NO), hydrogen sulfide (H₂S), and perhaps carbon monoxide (CO) in mammalian tissues. These gases are important in cellular processes associated with the cardiovascular system, inflammation, and neurological functions. Importantly, these studies build on the known biological effects of garlic and associated sulfur constituents. This review highlights our current understanding of the health benefits attributed to edible plants like garlic.

Alterations in the morphological, sugar composition, and volatile flavor properties of petai (Parkia speciosa Hassk.) seed during ripening

Petai seeds are one of the well-known strong-smelling foods of the Southeast Asian region that have been harvested and commercially offered in different ripening forms. The current study focused on alterations in the size, color, sugar composition, and volatile flavor properties of petai seeds in the four ripening stages (unripe, mid ripe, ripe, and over-ripe). The ripening process was mainly indicated by the increase in size and weight as seed color turned paler and less greenish. The total sugar content gradually increased during ripening, and then elevated from 1.60 g/100 g (ripe seed) to the level of 2.82 g/100 g in the over-ripe seed. Ripening also altered the volatile flavor composition of petai seed, wherein the predominant aldehydes (hexanal and acetaldehyde) were decreased, and the sulfuric compounds (hydrogen sulfide, methanethiol, and 1,2,4-trithiolane) tended to increase. Additionally, gas chromatography-olfactometry (GC-O) analysis revealed alterations in the perceived odor strength and sensation of each volatile compound and demonstrated volatile flavor profiles, viz. detection percentages of volatile group odor strengths and descriptive odors, of petai seed. These results provide valuable information for monitoring alterations in the physical appearance, sugar composition, and aroma that represent the flavor quality in seasonal petai seed.

International Union of Basic and Clinical Pharmacology. CII: Pharmacological Modulation of H2S Levels: H2S Donors and H2S Biosynthesis Inhibitors

Over the last decade, hydrogen sulfide (H2S) has emerged as an important endogenous gasotransmitter in mammalian cells and tissues. Similar to the previously characterized gasotransmitters nitric oxide and carbon monoxide, H2S is produced by various enzymatic reactions and regulates a host of physiologic and pathophysiological processes in various cells and tissues. H2S levels are decreased in a number of conditions (e.g., diabetes mellitus, ischemia, and aging) and are increased in other states (e.g., inflammation, critical illness, and cancer). Over the last decades, multiple approaches have been identified for the therapeutic exploitation of H2S, either based on H2S donation or inhibition of H2S biosynthesis. H2S donation can be achieved through the inhalation of H2S gas and/or the parenteral or enteral administration of so-called fast-releasing H2S donors (salts of H2S such as NaHS and Na2S) or slow-releasing H2S donors (GYY4137 being the prototypical compound used in hundreds of studies in vitro and in vivo). Recent work also identifies various donors with regulated H2S release profiles, including oxidant-triggered donors, pH-dependent donors, esterase-activated donors, and organelle-targeted (e.g., mitochondrial) compounds. There are also approaches where existing, clinically approved drugs of various classes (e.g., nonsteroidal anti-inflammatories) are coupled with H2S-donating groups (the most advanced compound in clinical trials is ATB-346, an H2S-donating derivative of the non-steroidal anti-inflammatory compound naproxen). For pharmacological inhibition of H2S synthesis, there are now several small molecule compounds targeting each of the three H2S-producing enzymes cystathionine-β-synthase (CBS), cystathionine-γ-lyase, and 3-mercaptopyruvate sulfurtransferase. Although many of these compounds have their limitations (potency, selectivity), these molecules, especially in combination with genetic approaches, can be instrumental for the delineation of the biologic processes involving endogenous H2S production. Moreover, some of these compounds (e.g., cell-permeable prodrugs of the CBS inhibitor aminooxyacetate, or benserazide, a potentially repurposable CBS inhibitor) may serve as starting points for future clinical translation. The present article overviews the currently known H2S donors and H2S biosynthesis inhibitors, delineates their mode of action, and offers examples for their biologic effects and potential therapeutic utility.