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1.
Chirality ; 34(9): 1166-1190, 2022 09.
Article in English | MEDLINE | ID: covidwho-2084347

ABSTRACT

Polysaccharides arouse great interest due to their structure and unique properties, such as biocompatibility, biodegradability, and absence of toxicity. Polysaccharides from marine sources are particularly useful due to the wide variety of applications and biological activities. Chitosan, a deacetylated derivative of chitin, is an example of an interesting bioactive marine-derived polysaccharide. Moreover, a wide variety of chemical modifications and conjugation of chitosan with other bioactive molecules are responsible for improvements in physicochemical properties and biological activities, expanding the range of applications. An overview of the synthetic approaches for preparing chitosan, chitosan derivatives, and conjugates is described and discussed. A recent update of the biological activities and applications in different research fields, mainly focused on the last 5 years, is presented, highlighting current trends.


Subject(s)
Chitosan , Chitin/chemistry , Chitosan/chemistry , Chitosan/pharmacology , Polysaccharides/chemistry , Polysaccharides/pharmacology , Stereoisomerism
2.
Synthetic and Systems Biotechnology ; 2022.
Article in English | ScienceDirect | ID: covidwho-2082875

ABSTRACT

The COVID-19 pandemic has caused severe health problems worldwide and unprecedented decimation of the global economy. Moreover, after more than 2 years, many populations are still under pressure of infection. Thus, a broader perspective in developing antiviral strategies is still of great importance. Inspired by the observed multiple benefits of heparin in the treatment of thrombosis, the potential of low molecular weight heparin (LMWH) for the treatment of COVID-19 have been explored. Clinical applications found that LMWH decreased the level of inflammatory cytokines in COVID-19 patients, accordingly reducing lethality. Furthermore, several in vitro studies have demonstrated the important roles of heparan sulfate in SARS-CoV-2 infection and the inhibitory effects of heparin and heparin mimetics in viral infection. These clinical observations and designed studies argue for the potential to develop heparin mimetics as anti-SARS-CoV-2 drug candidates. In this review, we summarize the properties of heparin as an anticoagulant and the pharmaceutical possibilities for the treatment of virus infection, focusing on the perspectives of developing heparin mimetics via chemical synthesis, chemoenzymatic synthesis, and bioengineered production by microbial cell factories. The ultimate goal is to pave the eminent need for exploring novel compounds to treat coronavirus infection-caused diseases.

3.
Biocatalysis and Agricultural Biotechnology ; : 102470, 2022.
Article in English | ScienceDirect | ID: covidwho-2007464

ABSTRACT

Essential oil extracted from plants has many applications in the field of medicine, cosmetic and pharmaceuticals due to cost effectiveness and therapeutic effects associated. In this article, we have compiled discussion on the essential oil extracted from ginger, cinnamon, and lemon leaves. Essential oils are rich source of antioxidant compounds like cinnamaldehyde, zingiberene and limonene. This review article covers the literature related to antioxidant and biological activities of essential oils extracted from ginger, cinnamon and lemon. In addition, applications of the essential oils in the field of medical, pharmacology, cosmetic etc, have been discussed. Role of essential oils, for anti-cancer, anti-hypertension, reduction of heart diseases and maintaining of blood circulation and digestion due to presence of antioxidant components, has been discussed. Literature has also supported Covid-19 preventive effects of essential oils. Keeping in view the positive effects on health, essential oils can be used as supplements. Furthermore, essential oils must be further investigated for their biological activities followed by development of essential oil based drugs and pharmaceutics.

4.
Journal of Shahrekord University of Medical Sciences ; 24(3):145-152, 2022.
Article in English | Academic Search Complete | ID: covidwho-2002875

ABSTRACT

Background and aims: Curcumin or diferuloylmethane is derived from ferulic acid. This herbal compound has a particular chemical structure and various biological/medical properties. The functional groups in the curcumin structure and its analogs are involved in the formation of specific biological activities. This natural compound has high bioactivity, as well as the potential to treat diseases such as cancer, Alzheimer’s, diabetes, and severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Considering the spread of infectious diseases and cancers in recent years, as well as an increase in drug resistance and side effects, providing effective and available treatments is necessary. Methods: This review explained the chemical structure of curcumin and covered its biological properties, including anti-inflammation, antioxidant, anti-cancer, neuroprotective, anti-diabetic, and anti-SARS-CoV-2 activities. Scientific databases were studied to gather the required information. Results: Curcumin affected several molecular pathways, including activating transcription factors, cell growth factors, anti-inflammatory agents, protein kinases, cytokines, and apoptotic pathway factors. Thus, it had beneficial therapeutic effects on health. Conclusion: By targeting a wide range of molecular mechanisms, curcumin has the potential to treat various diseases. Knowledge of curcumin’s pharmacological/biological activities and its action mechanisms can enhance the applications of curcumin as a potentially bioactive and therapeutic compound. [ FROM AUTHOR] Copyright of Journal of Shahrekord University of Medical Sciences is the property of Journal of Shahrekord University of Medical Sciences and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full . (Copyright applies to all s.)

5.
Current Research in Nutrition and Food Science ; 10(1):31-44, 2022.
Article in English | Web of Science | ID: covidwho-1870122

ABSTRACT

Coronavirus disease 2019 (COVID-19) pandemic caused by Severe Acute Respiratory Syndrome Coronavirus- 2 (SARS-CoV-2) due to its rapid community transmission and absence of an effective antiviral drug has caused a high morbidity and mortality in human lives world over. According to the WHO Situation Report No. 102 as on January 12, 2022, India recorded 35.87 million confirmed cases of COVID 19 with a death rate of 1.34 %, the total death being 0.48 million, in comparison to the global death rate of 1.78%. The host-pathogen interactions are important to understand an infectious disease and to follow specific treatment for cure and measures for prevention. Various factors involved in disease emergence with interplay between pathogens, hosts and environment changes the disease ecology creating novel transmission patterns and severity. Indian conventional foods and culinary spices contain a number of active principles, including polysaccharides, terpenoids, alkaloids, flavonoids, glycosides, and essential oils, which act as immunomodulators and have tremendous capability to maintain and/or stimulate the immune system primarilythrough the modulation of nonspecific immune responses. This review highlights the bioactive components of some of the most commonly used Indian culinary spices grounding a new dimension of research on these natural phytoproducts to bring out their functional and medicinal values vis-a-vis improvement of human health. In conclusion, the structure of bioactive molecules present in the Indian dietary spices may pave way for the development of anti-SARS-CoV-2 drugs for the prevention and treatment of COVID-19.

6.
Computational Toxicology ; : 100231, 2022.
Article in English | ScienceDirect | ID: covidwho-1850910

ABSTRACT

Due to theirinteresting hydrogen-bonding properties, Schiff bases are known for their variety of applications in chemistry and medicinal chemistry. In this work, the interaction between symmetrical Schiff base ligand (L: bis [4-hydroxy-6-methyl-3-{(1E)-N-[2 (ethylamino) ethyl] ethanimidoyl}-2H-pyran-2-one]) and cancer cells, neurological, viruses and bacteria receptors was studied theoretically. Density functional theory (DFT) was used to determine the geometry, reactivity and electronic properties of this ligand. Homology modeling and molecular docking were performed to check their biological and medicinal properties, including anticancer, antiviral, antibacterial and neurological activities. DFT revealed that the mulliken charges, the molecular orbitals (HOMO and LUMO) and MEP results are in a good agreement to the localization of electrophilic and nucleophilic attack sites. The theoretical study showed a high chemical reactivity and a low kinetic stability of the ligand. The docking study results revealed that the ligand exhibits a good biological activity against leukemia, breast cancer, Alzheimer and Covid-19 with binding energy values of -7.36 kcal/mol, -6.35 kcal/mol, -6.19 kcal/mol and -5.58 kcal/mol, respectively. These results are explained by the low values of binding energy and inhibition constant and multiple H-bonds.

7.
Journal of Pharmacy & Pharmacognosy Research ; 10(3):357-386, 2022.
Article in English | Web of Science | ID: covidwho-1717293

ABSTRACT

Context: The contagious global pandemic of coronavirus 2019 (COVID-19) has prompted many Moroccans to turn to traditional phytoremedies. Aims: To highlight the ethnopharmacological information and the risks of intoxication related to the use of herbal medicine to combat COVID-19. Methods: Through a semi-structured questionnaire and using the "Free listing" technique, an ethnobotanical survey was conducted among 36 herbalists of the Meknes prefecture to collect ethnopharmacological data on species used in the fight against COVID-19. Then, many databases were used to document their pharmacological and toxicological activities. Results: A total of 36 species in 22 families were reported to be used to prepare traditional recipes against COVID-19. According to the relative frequency index of citation, the species Artemisia herba-alba Asso, Eucalyptus globulus Labill, Syzygium aromaticum (L.) Merr. & L.M. Perry, Citrus limon (L.) Osbeck, and Zingiber officinale Roscoe. were recommended by all respondents and recorded the highest usage values. Based on the value of the plant parts index, leaves were the most used part (PPV = 0.37). Most of the remedies were prepared as infusions and administered orally. The bibliographic research revealed that the plants used have several biological activities and are frequently used to treat respiratory diseases. However, some of them have been reported to be toxic. Conclusions: Recommended species are endowed with innumerable biological activities. They can be a promising alternative to combat COVID-19. However, their toxic effects require pharmacotoxicological studies to ensure the safety and efficacy of these natural remedies.

8.
Studia Universitatis Babes-Bolyai Chemia ; 66(4):107-122, 2021.
Article in English | Web of Science | ID: covidwho-1579405

ABSTRACT

The important molecule tryptophan and its derivatives serotonin and melatonin have vital functions in human and plant biosystem. Recent reports claimed these molecules and parthenolide may also have a role in COVID-19 treatments. Herewith the study, contents of chlorogenic acid, cynarin, quinic acid, parthenolide, and tryptophan derivatives in leaf and flowers of seven species of Tanacetum from Turkey were examined using HPLC. The methanolic extracts of the species were also screened for their total phenolic content and DPPH scavenging activity. Regarding to HPLC data, the highest amount of chlorogenic acid and cynarin were detected in T. cilicicum, quinic acid in T. densum subsp. amani and parthenolide in T. argenteum subsp. argenteum leaves. Also, the highest amount of tryptophan and serotonin were estimated in T. argenteum subsp. argenteum. Melatonin content was highest in T. densum subsp. amani. All Tanacetum species exhibited potent antioxidant activities. T. densum subsp. amani (Afsin) flowers had higher DPPH activity than control group BHT and T. cilicicum leaves and flowers had the highest total phenolic content. Herewith, phenolic profiles of T. argenteum subsp. argenteum, T. armenum and T. densum subsp. amani and tryptophan derivates of the species were reported for the first time.

9.
Foods ; 10(11)2021 Oct 30.
Article in English | MEDLINE | ID: covidwho-1488529

ABSTRACT

Cordyceps spp. mushrooms have a long tradition of use as a natural raw material in Asian ethnomedicine because of their adaptogenic, tonic effects and their ability to reduce fatigue and stimulate the immune system in humans. This review aims to present the chemical composition and medicinal properties of Cordyceps militaris fruiting bodies and mycelium, as well as mycelium from in vitro cultures. The analytical results of the composition of C. militaris grown in culture media show the bioactive components such as cordycepin, polysaccharides, γ-aminobutyric acid (GABA), ergothioneine and others described in the review. To summarize, based on the presence of several bioactive compounds that contribute to biological activity, C. militaris mushrooms definitely deserve to be considered as functional foods and also have great potential for medicinal use. Recent scientific reports indicate the potential of cordycepin in antiviral activity, particularly against COVID-19.

10.
Phytochem Rev ; 21(3): 725-764, 2022.
Article in English | MEDLINE | ID: covidwho-1384539

ABSTRACT

Flavaglines are formed by cycloaddition of a flavonoid nucleus with a cinnamic acid moiety representing a typical chemical character of the genus Aglaia of the family Meliaceae. Based on biosynthetic considerations 148 derivatives are grouped together into three skeletal types representing 77 cyclopenta[b]benzofurans, 61 cyclopenta[bc]benzopyrans, and 10 benzo[b]oxepines. Apart from different hydroxy, methoxy, and methylenedioxy groups of the aromatic rings, important structural variation is created by different substitutions and stereochemistries of the central cyclopentane ring. Putrescine-derived bisamides constitute important building blocks occurring as cyclic 2-aminopyrrolidines or in an open-chained form, and are involved in the formation of pyrimidinone flavaglines. Regarding the central role of cinnamic acid in the formation of the basic skeleton, rocagloic acid represents a biosynthetic precursor from which aglafoline- and rocaglamide-type cyclopentabenzofurans can be derived, while those of the rocaglaol-type are the result of decarboxylation. Broad-based comparison revealed characteristic substitution trends which contribute as chemical markers to natural delimitation and grouping of taxonomically problematic Aglaia species. A wide variety of biological activities ranges from insecticidal, antifungal, antiprotozoal, and anti-inflammatory properties, especially to pronounced anticancer and antiviral activities. The high insecticidal activity of flavaglines is comparable with that of the well-known natural insecticide azadirachtin. Comparative feeding experiments informed about structure-activity relationships and exhibited different substitutions of the cyclopentane ring essential for insecticidal activity. Parallel studies on the antiproliferative activity of flavaglines in various tumor cell lines revealed similar structural prerequisites that let expect corresponding molecular mechanisms. An important structural modification with very high cytotoxic potency was found in the benzofuran silvestrol characterized by an unusual dioxanyloxy subunit. It possessed comparable cytotoxicity to that of the natural anticancer compounds paclitaxel (Taxol®) and camptothecin without effecting normal cells. The primary effect was the inhibition of protein synthesis by binding to the translation initiation factor eIF4A, an ATP-dependent DEAD-box RNA helicase. Flavaglines were also shown to bind to prohibitins (PHB) responsible for regulation of important signaling pathways, and to inhibit the transcriptional factor HSF1 deeply involved in metabolic programming, survival, and proliferation of cancer cells. Flavaglines were shown to be not only promising anticancer agents but gained now also high expectations as agents against emerging RNA viruses like SARS-CoV-2. Targeting the helicase eIF4A with flavaglines was recently described as pan-viral strategy for minimizing the impact of future RNA virus pandemics.

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