Preparation, structural characterization, and bioactivities of polysaccharides from Psidium guajava: A review

Extraction, structure, activity and application of konjac glucomannan

Konjac is a perennial herbaceous plant from the Araceae family's Amorphophallus genus. It has high nutritional, health, and pharmacological values. It contains various bioactive components, the most notable of which is konjac glucomannan, which has several biological roles, including efficiently fighting diabetes, exerting prebiotic activity, containing antioxidant capacity, modulating immunological function, and demonstrating anti-cancer potential. Currently, the konjac glucomannan (KGM) research mainly focuses on packaging film, gel characteristics, efficacy, and evaluation. However, the extraction, underlying portrayal, derivatization, and action of KGM are seldom detailed. Herein, the utilization of konjac as an unrefined substance was surveyed, meaning to give extensive and orderly recombinant data on the extraction, decontamination, structure, natural movement, derivatization, and use of KGM to provide a full play to the interesting gelatinate, biocompatibility, high viscosity and other properties of KGM. It provided a theoretical basis for further developing the konjac glucomannan food industry, pharmaceutical field, and other fields.

Bioactive Compounds from Guava Leaves (Psidium guajava L.): Characterization, Biological Activity, Synergistic Effects, and Technological Applications

The characteristics of bioactive compounds from guava (Psidium guajava L.) leaf extract, their biological activity, and their technological applications are critical topics in many engineering fields. Guava leaf extract is rich in bioactive compounds, including phenolic acids, flavonoids, tannins, terpenes, alkaloids, etc. Bioactive compounds from guava leaf exhibit notable synergistic effects in enzyme inhibition, as well as antimicrobial and anti-inflammatory activities. Natural bioactive compounds are complicated due to their sensitivity and instability during storage, but their use is promising. Thus, for bioactive compound protection, advanced techniques such as the encapsulation, microemulsion, and nanosuspension of such natural bioactive compounds can be a promising approach. These methods are particularly important for the development of natural preservatives serving as additive agents, which have significant industrial relevance. However, sufficient scientific evidence is required to make a health claim on and to promote the functional benefits of guava leaf extract. This review focuses on recent research into guava leaf extract and its technical roles. Demonstrations of the chemical structure of bioactive compounds are addressed, besides discussing their analytical methods, nutritional bioavailability, biological activity, and synergy effects. Furthermore, this review study considers the methods used to protect the active compounds and technological applications in food, pharmaceuticals, and cosmetic products.

Preparation, structural characterization, and bioactivities of polysaccharides from Rhodiola: A review

Rhodiola, the dried rhizome of various plants of the family Crassulaceae and genus Rhodiola, has been used as a traditional Tibetan medicine for thousands of years, with high medicinal and healthcare value. Polysaccharides, the major active components of Rhodiola, have attracted widespread attention due to their abundant biological activities and medicinal value. Rhodiola polysaccharides (RPs) have various biological activities such as germ cell protection, antioxidant, immunomodulatory, anti-fatigue, hypoglycemic, anti-tumor, and hematopoietic functions. The biological activities of RPs are closely related to their structures and different extraction and purification methods produce different polysaccharide structures. This review aims to provide a comprehensive overview of the research progress in the extraction, purification, structural characterization, bioactivity, potential mechanisms, and structural modification of RPs as well as their potential development prospects and future promising research directions, to lay a foundation for the further development of RP pharmaceutical products.

Low-pressure cold plasma pretreatment: Impact on quality attributes of "Fan Retief" guava and efficacy against Colletotrichum gloeosporioides

This work investigated the impact of low-pressure cold plasma (CP) as a pretreatment with polyethylene terephthalate (PET) plastic trays or open corrugated cardboard (OCC) boxes on the overall quality of "Fan Retief" guava fruits stored for 28 days at 13°C. Untreated samples placed in PET and OCC served as control. Guava fruits followed typical climacteric responses, but CP-treated samples significantly slowed down respiration (RRCO2) and ethylene production rate during storage (p ≤ 0.05). On day 28, CP-treated samples retained the highest titratable acidity and total phenolics compared to untreated samples (p ≤ 0.05). Overall, CP pretreatment better maintained the relative abundance of characteristic volatile compounds for guava fruits during storage, effectively delayed decay incidence, and inhibited the growth of Colletotrichum gloeosporioides in vivo compared to control. PRACTICAL APPLICATION: This study demonstrated low-pressure cold plasma as a potential alternative phytosanitary tool for the postharvest handling of guava fruit.

Exploring the structure-activity relationship of Safflower polysaccharides: From the structural characteristics to biological function and therapeutic applications

ETHNOPHARMACOLOGICAL RELEVANCE

Safflower, the florets of Carthamus tinctorius L., is a widely used traditional Chinese medicine for promoting circulation and improving dysmenorrhea. Polysaccharides is one of the principal water-soluble components in Safflower, which recently endowed with a variety of biological activities, thus making them have important research significance in the field of ethnopharmacology.

AIM OF THE STUDY

This review summarized the latest research progress on the preparation technology, structural characteristics, and pharmacological effects of Safflower polysaccharides. Moreover, by comparing the structural characteristic of Safflower polysaccharides, the potential structure-activity relationship of Safflower polysaccharides was also discussed.

MATERIALS AND METHODS

This article used keywords including Safflower polysaccharide, Carthamus tinctorius L polysaccharide, Safflower polysaccharide extraction and separation, Safflower polysaccharide structure, and Safflower polysaccharide anti-tumor effects to search for all relevant literature in PubMed, Web of Science, Google Scholar, ScienceDirect, CNKI and other databases from the establishment of the database to July 2024.

RESULTS

Summarizing current research findings, seventeen homogeneous Safflower polysaccharides have been obtained. Their structural characteristics, including molecular weights, monosaccharide composition, sugar residue types, glycosidic bond configuration, and the linkage sequence, were initially researched. In terms of pharmacological activity, Safflower polysaccharides exhibit a wide range of biological activities, including immune regulation, anti-tumor effects, and antioxidant properties. Furthermore, the structural characteristics of Safflower polysaccharides significantly influence its biological activities, encompassing factors such as molecular weight, monosaccharide composition, and degree of branching.

CONCLUSION

Safflower polysaccharides have seen significant advancements in recent years regarding preparation methods, structural characterization, and pharmacological studies. These achievements would provide a theoretical basis for the application of Safflower polysaccharide in the field of ethnopharmacology. While Safflower polysaccharides exhibit diverse biological activities and significant potential for development and utilization, further in-depth research is needed to enhance our understanding of their mechanisms of action and optimize their clinical applications.

Research progress on extraction techniques, structure-activity relationship, and biological functional mechanism of berry polysaccharides: A review

In recent years, polysaccharides extracted from berries have received great attention due to their various bioactivities. However, the preparation and application of berry polysaccharides have been greatly limited due to the lack of efficient extraction techniques, unclear structure-activity relationships, and ambiguous functional mechanisms. This review discusses the technological progress in solvent extraction, assisted extraction, critical extraction, and combination extraction. The structure-activity relationship and functional mechanism (antioxidation, hypoglycemic, immunoregulation etc.) of berry polysaccharides are reviewed. After systematic exploration, we believe that industrial production is more suitable for using efficient and low-cost extraction methods, such as ultrasonic assisted extraction and microwave assisted extraction. And some of the bioactivities (antioxidant activity, hypoglycemic activity, etc.) of berry polysaccharides are closely related to their structure (molecular weight, monosaccharide composition, branching structure, etc.). Besides, berry polysaccharides exhibit bioactivities by regulating enzyme activity, cellular metabolism, gene expression, and other pathways to exert their effects on the body. These findings indicate the potential of berry polysaccharides as functional foods and drugs. This paper will contribute to the preparation, bioactivity research, and application of berry polysaccharides.

Caseinate-coated zein nanoparticles as potential delivery vehicles for guavinoside B from guava: Molecular interactions and encapsulation properties

Guavinoside B (GUB) is a characteristic constituent from guava with strong antioxidant activity; however, its low water solubility limits its utilization. Herein, we investigated the interaction between GUB and zein, a prolamin with self-assembling property, using multiple spectroscopic methods and fabricated GUB-zein-NaCas nanoparticles (GUB-Z-N NPs) via the antisolvent coprecipitation approach. GUB caused fluorescence quenching to zein via the static quenching mechanism. Fourier-transform infrared spectroscopy and computational analysis revealed that GUB bound to zein via van der Waals interaction, hydrogen bond, and hydrophobic forces. The GUB-Z-N NPs were in the nanometric size range (< 200 nm) and exhibited promising encapsulation efficiency and redispersibility after freeze-drying. These particles remained stable for up to 31 days at 4 °C and great resistance to salt and pH variation, and displayed superior antioxidant activity to native GUB. The current study highlights the potential of zein-based nanoparticles as delivery vehicles for GUB in the food industry.

Application of ionic liquid ultrasound-assisted extraction (IL-UAE) of lycopene from guava (Psidium guajava L.) by response surface methodology and artificial neural network-genetic algorithm

Lycopene-rich guava (Psidium guajava L.) exhibits significant economic potential as a functional food ingredient, making it highly valuable for the pharmaceutical and agro-food industries. However, there is a need to enhance the extraction methods of lycopene to fully exploit its beneficial uses. In this study, we evaluated various ionic liquids to identify the most effective one for extracting lycopene from guava. Among thirteen ionic liquids with varying carbon chains or anions, 1-butyl-3-methylimidazolium chloride demonstrated the highest productivity. Subsequently, a single-factor experiment was employed to test the impact of several parameters on the efficiency of lycopene extraction using this selected ionic liquid. These parameters included extraction time, ultrasonic power, liquid-solid ratio, concentration of the ionic liquid, as well as material particle size. Moreover, models of artificial neural networks using genetic algorithms (ANN-GA) and response surface methodology (RSM) were employed to comprehensively assess the first four key parameters. The optimized conditions for ionic liquid ultrasound-assisted extraction (IL-UAE) were determined as follows: 33 min of extraction time, 225 W of ultrasonic power, 22 mL/g of liquid-solid ratio, 3.0 mol/L of IL concentration, and extraction cycles of three. Under these conditions, lycopene production reached an impressive yield of 9.35 ± 0.36 mg/g while offering advantages such as high efficiency, time savings, preservation benefits, and most importantly environmental friendliness.

Recent trends in extraction, purification, structural characterization, and biological activities evaluation of Perilla frutescens (L.) Britton polysaccharide

Perilla frutescens (L.) Britton is an annual herb plant of the Perilla genus in the Labiatae family, which is commonly utilized as an edible and medicinal resource. Polysaccharides are among the major components and essential bioactive compounds of P. frutescens, which exhibit a multitude of biological activities, including antioxidant, antitumor, anti-fatigue, immunoregulation, hepatoprotective, anti-inflammatory, and lipid-lowering effects. As a natural carbohydrate, P. frutescens polysaccharide has the potential to be utilized in the development of drugs and functional materials. In this paper, we provide an overview of progress made on the extraction, purification, structural characterization, and bioactivity of polysaccharides from different parts of P. frutescens. The challenges and opportunities for research are discussed, along with the potential development prospects and future areas of focus in the study of P. frutescens polysaccharides.

Molecular Detection of Secreted Aspartyl Proteinases (Saps) From Dental Isolates of Candida albicans and Targeting With Psidium guajava Biocompounds: An In Vitro and In Silico Analysis

Introduction Candida albicans (C. albicans) is an opportunistic yeast-like fungus and is considered a functional biome of the oral and gut microbiomes. The sap gene and its types play a vital role in the pathogenesis of C. albicans. The emergence of resistance traits is a major problem, and targeting the same with alternative medicines has sparked renewed interest in recent years. Objectives This study is thus aimed at detecting the frequency of sap gene types in the clinical isolates of C. albicans and evaluating the antifungal effect of the crude methanolic extract of Psidium guajava (P. guajava). Further in silico assessments will assess the inhibitory effect of six compounds of P. guajava against the Sap protein. Materials and methods C. albicans was characterized phenotypically in 20 patients with root caries, and the sap gene was detected by PCR. The crude methanolic extract was prepared, and its antifungal efficacy was evaluated by the agar well diffusion method. Auto-docking was performed to assess the best compound based on the docking and overall interactions. Results Six isolates were identified as C. albicans and sap gene types 1-3 were detected in the four strains. P. guajava methanolic extracts showed a promising antifungal effect at varying concentrations. In silico analysis showed myricetin possessing the maximum number of hydrogen bonds and high docking energy with one violation. Conclusion The study concludes that P. guajava has a promising inhibitory effect against C. albicans with myricetin as the best compound to target the sap gene of C. albicans. However, further experimental studies are to be considered for its effectiveness in treating the infections caused by C. albicans.

Optimization of Extraction Process, Preliminary Characterization and Safety Study of Crude Polysaccharides from Morindae Officinalis Radix

In this study, the hot water extraction process of crude polysaccharides from Morindae officinalis radix (cMORP) was conducted and optimized through a single-factor test and orthogonal experimental design. With the optimal extraction process (extraction temperature of 80 °C, extraction time of 2 h, liquid/solid ratio of 15 mL/g, and number of extraction of 1), the cMORP was obtained by the ethanol precipitation method. The chemical properties and preliminary characterization of the cMORP were analyzed by chemical or instrumental methods. Furthermore, to indicate a preliminary study on safety, a single oral dose of 5000 mg/kg body weight (BW) was administered orally to Kunming (KM) mice for acute toxicity, and the cMORP was administered orally to KM mice once a day at doses of 25, 50, and 100 mg/kg BW for 30 days. General behaviors, body weight variations, histopathology, relative organ weights, and hematological and serum biochemical parameters were observed and recorded. The results suggested there were no toxicologically significant changes. Based on the safety study, cMORP can be initially considered non-toxic with no acute oral toxicity up to 5000 mg/kg BW and safe at up to 100 mg/kg BW in KM mice for 30 days.