Eugenol isolated from supercritical fluid extract of Ocimum sanctum: a potent inhibitor of DENV-2.

Dengue is one of the fairly prevalent viral infections at the world level transmitted through mosquitoes (Aedes aegypti and Aedes albopictus). Due to various environmental factors, dengue cases surged rapidly at the global level in recent decades, with 193245 cases in 2021 and an increment of 110473 cases in 2022. There is no antidote available against dengue and other flaviviruses. In the absence of a dengue vaccine or specific antiviral, medicinal plants or their products can be the only choice for its effective management. Ocimum sanctum is known as ''The Incomparable One,'' ''Mother Medicine of Nature'' and ''Queen of Herbs'' in Ayurveda, and is considered an "elixir of life" supreme in both healthcare and spiritual terms. In present study eugenol was isolated in O.sanctum. Eugenol (1-hydroxy-2-methoxy-4-allylbenzene) has been substantially responsible for its therapeutic potential. High-performance thin-layer chromatography, Fourier transform infrared spectroscopy and ultraviolet-visible spectroscopy were applied to identify the compound. The Rf value of isolated compound was same in the chromatogram (0.69 + 0.05) with compare to standard. The safe dose of plant and eugenol were found as < 31.25 µg/ml and < 15.62 µg/ml. The anti-dengue activity was assessed in C6/36 cell lines, their effect was determined through Quantitative PCR. The NMR of the isolated eugenol showed similar properties as the commercial marker compound. The eugenol and SFE extract of O. sanctum showed the inhibition of 99.28% and completely against Dengue-2, respectively. Docking study exposed that the interaction of eugenol with NS1 and NS5 dengue protein showed the binding energy as - 5.33 and - 5.75 kcal/mol, respectively. The eugenol from the O. sanctum plant has the potential to be a good source of future treatment medications for dengue illness, as well as a valuable tool in its successful management.

Monkeypox virus is nature's wake-up call: a bird's-eye view.

Several infections have emerged in humans, domestic animals, wildlife, and plant populations, causing a severe problem for humanity. Since the discovery of the Monkeypox virus (Mpox) in 1958 in Copenhagen, Denmark, it has resurfaced several times, producing severe infections in humans and resulting in a significant fatality rate. Mpox is an Orthopoxvirus of the Poxviridae family. This family contains various medically important viruses. The natural reservoir of Mpox is unknown yet. Mpox might be carried by African rodents and nonhuman primates (such as monkeys). The role of monkeys has been confirmed by its various outbreaks. The infection may be transferred from unidentified wild animals to monkeys, who can then spread it to humans by crossing species barriers. In close contact, human-to-human transmission is also possible. Mpox outbreaks have been documented regularly in Central and Western Africa, but recently in 2022, it has spread to over one hundred-six countries. There is no specific treatment for it, although the smallpox vaccine, antivirals, and vaccinia immune globulin help in the effective management of Mpox. In conclusion: Monkeypox poses a severe threat to public health due to the lack of specific vaccinations and effective antivirals. Surveillance studies in affected regions can assist in the early diagnosis of disease and help to control significant outbreaks. The present review provides information on epidemiology, clinical symptoms, risk factors, diagnosis, and preventive measures of Mpox.

Hepatitis B virus-induced hepatocellular carcinoma: a persistent global problem.

Hepatitis B virus (HBV) infections are highly prevalent globally, representing a serious public health problem. The diverse modes of transmission and the burden of the chronic carrier population pose challenges to the effective management of HBV. Vaccination is the most effective preventive measure available in the current scenario. Still, HBV is one of the significant health issues in various parts of the globe due to non-response to vaccines, the high number of concealed carriers, and the lack of access and awareness. Universal vaccination programs must be scaled up in neonates, especially in the developing parts of the world, to prevent new HBV infections. Novel treatments like combinational therapy, gene silencing, and new antivirals must be available for effective management. The prolonged infection of HBV, direct and indirect, can promote the growth of hepatocellular carcinoma (HCC). The present review emphasizes the problems and probable solutions for better managing HBV infections, causal risk factors of HCC, and mechanisms of HCC.

The Cat Que Virus: a resurfacing orthobunyavirus could lead to epidemics.

The newly emerging and re-emerging of viral contagion in the present scenario are of more extensive health concern. After a long calm of many years, an unexpected eruption of the Cat Que Virus in China is a source of our concern. Cat Que Virus is an Arbovirus and belongs to the Simbu serogroup of the Orthobunyavirus genus of the Bunyaviridae family. The Simbu serogroup is an extremely diverse group of Arbovirus. The arboviruses are causing the infection in multiple hosts including humans and various livestock. They can cause mild to life-threatening infections. Arboviruses expand their spectrum and are more observable in recent times. Human actions have the most significant geophysical impact on the environment. Changes in rainfall patterns, floods, and the risk of extreme weather events are all consequences of climate change. These events may be connected to the extension of permissive vectors, geographic ranges, and therefore provide more chance of growth and spread of potential vector. Arboviruses are responsible for the health hazard to millions of people globally. It is critical to concentrate research and surveillance on these emerging and re-emerging viruses, particularly arthropod-borne viral infections. The appropriate research and surveillance on them will help us for the development of effective control and treatment strategies and also reduce health problems. The present review summarizes the current broad outline of discovery, evolution and dispersal of this unknown virus.

Anti-dengue activity of super critical extract and isolated oleanolic acid of Leucas cephalotes using in vitro and in silico approach.

BACKGROUNDS: Leucas cephalotes is a common ethnomedicinal plant widely used by traditional healers for the treatment of Malaria and other types of fever. Oleanolic acid and its derivatives have been reported for various types of pharmacological activities, such as anti-inflammatory, antioxidant, anticancer, hepatoprotective, anti-HIV and anti-HCV activity. METHODS: L.cephalotes plant extracts were prepared by supercritical fluid extraction (SFE) method and oleanolic acid was isolated by preparatory thin-layer chromatography. The compound was identified and characterize by using ultraviolet-visible spectroscopy (UV-VIS), Fourier transform infra-Red spectroscopy (FT-IR) and high-performance thin-layer chromatography (HPTLC). The structure of the compound was elucidated by proton nuclear magnetic resonance (1HNMR) and carbon nuclear magnetic resonance (1CNMR) and the purity checked by differential scanning calorimetry (DSC). The MTT assay was used to determine the toxicity of plant extract and oleanolic acid using a microplate reader at 595 nm. The anti-dengue activity of plant extract and oleanolic acid was tested in vitro and in silico using real-time RT-PCR. RESULTS: The optimum yield of the extract was obtained at 40 °C temperature and 15Mpa pressure. The maximum non-toxic dose (MNTD) of plant extract and oleanolic acid were found as 46.87 µg/ml and 93.75 µg/ml, respectively in C6/36 cell lines. UV spectrophotometer curve of the isolated compound was overlapped with standard oleanolic acid at 232 nm. Superimposed FT-IR structure of the isolated compound was indicated the same spectra at 3433, 2939, 2871, 1690, 1500,1463, 1387, 1250, 1209, 1137 and 656 position as per marker compound. HPTLC analysis showed the retention factor of L. cephalotes extract was 0.19 + 0.06 as similar to the standard oleanolic acid chromatogram. The NMR structure of the isolated compound was identified as similar to the marker oleanolic acid structure. DSC analysis revealed the purity of isolated oleanolic acid was 98.27% with a melting point of 311.16 °C. Real-time RT PCR results revealed that L. cephalotes supercritical extract and isolated oleanolic acid showed 100 and 99.17% inhibition against the dengue - 2 virus when treated with MNTD value of plant extract (46.87 µg/ml) and the test compound (93.75 µg/ml), respectively. The molecular study demonstrated the binding energy of oleanolic acid with NS1and NS5 (non-structural protein) were - 9.42 & -8.32Kcal/mol, respectively. CONCLUSIONS: The SFE extract L. cephalotes and its active compound, oleanolic acid inhibiting the activity of dengue-2 serotype in the in vitro and in silico assays. Thus, the L.cephalotes plant could be an excellent source for drug design for the treatment of dengue infection.

In-vitro and in-silico evaluation of the anti-chikungunya potential of Psidium guajava leaf extract and their synthesized silver nanoparticles.

Chikungunya is a notorious viral infection, which affects a large segment of world populations in absence of vaccines and antivirals. The current study evaluates of anti-chikungunya activities of Psidium guajava leaves extract and their green synthesized silver nanoparticles. Green synthesized nanoparticles were well characterized for their size and stability by dynamic light scattering (DLS), zeta potential, scanning electron microscopy (SEM) and their functional groups were analyzed by FTIR. Maximum non-toxic doses (MNTD) of extracts and nanoparticles were analysed by using Vero cell-lines. Anti-chikungunya activities of extracts and nano-particles were determined on Vero cells and their effects on cell viability were measured by MTT assay. The P. guajava nano-particles and extracts revealed the anti-chikungunya activities in the Vero cell. The cells viability was increased by 40% and 60% as compared to the virus control, when these cells were treated with MNTD of P. guajava nano-particles and extracts, respectively. To know the reason for antiviral activity, molecular docking of phytochemicals was done against a replication essential cysteine protease (nsP2) of Chikungunya. It was found that phytochemicals; Longifollen and Quercetin showed the minimum binding energy with nsP2. P. guajava extracts can be exploited to develop an effective anti-chikungunya agent. In the absence of CHIKV vaccines and antivirals, P. guajava may be used to develop rapid, responsive, specific, and cost-effective anti-chikungunya agents. Supplementary Information: The online version contains supplementary material available at 10.1007/s13337-021-00685-4.

Identification and characterization of new potent inhibitors of dengue virus NS5 proteinase from Andrographis paniculata supercritical extracts on in animal cell culture and in silico approaches.

ETHNOPHARMACOLOGICAL RELEVANCE: About 2.5 billion peoples are at risk of dengue virus and the majority of people, use traditional plant-based medicines to combat dengue. The whole plant of Andrographis paniculata used traditionally over past decades for health promotion. Andrographolide isolated from Andrographis paniculata is used as natural remedy for the treatment of various diseases in different parts of the world. Andrographolide has been reported to have antiviral activity against hepatitis B virus, hepatitis C virus, herpes simplex virus, influenza virus, chikungunya virus, dengue virus 2 and 4. AIM OF THE STUDY: The aim of the present study to isolate the andrographolide from the A. paniculata by supercritical fluid extraction technique and to characterize the isolated compound along with it anti-dengue activity against DENV-2 in vitro and in silico methods. MATERIALS AND METHODS: Supercritical extraction condition for A. paniculata was standardised to isolate andrographolide compound at definite temperature and pressure on the basis of previous study. The andrographolide was identified by using Ultraviolet-Visible Spectroscopy (UV-VIS), Fourier-Transform Infrared Spectroscopy (FT-IR) and High Performance Thin Layer Chromatography (HPTLC) and Proton Nuclear Magnetic Resonance (1HNMR). The maximum non-toxic dose of isolated andrographolide was detected by MTT assay using a micro plate reader at 595 nm. One hundred (100) copies/ml of the DENV-2 virus was used for antiviral assay in C6/36 cells lines and inhibition of virus due to andrographolide was determined by real-time PCR assay. The purity of isolated andrographolide was determined by Differential Scanning Calorimetry (DSC). The dengue NS5 receptor protein was docked with andrographolide and evaluated on the basis of the total energy and binding affinity score by Auto Dock (V4.2.6) software. RESULTS: Andrographolide, a diterpene lactone was isolated from the A. paniculata supercritical extract at 40 °C temperature and 15 Mpa pressure. UV spectrophotometer analysis revealed that the curve of andrographolide plant extract was overlapped with reference compound at 228 nm and the similar bands were detected from FT-IR spectroscopy analysis at 3315, 2917, 2849, 1673, 1462 and 1454 cm-1 in isolated and standard andrographolide. HPTLC analysis shows the retention factor (Rf) of A. paniculata extract at 0.74 ± 0.06 as similar to standard andrographolide Rf values. The purity of isolated andrographolide was 99.76%. The maximum non-toxic dose of isolated andrographolide was found as 15.62 µg/ml on the C6/36 cell line calculated by using MTT assay. The andrographolide showed the 97.23% anti-dengue activity against the dengue-2 virus in C6/36 cell lines. Results of molecular docking showed that the interaction between andrographolide and NS5 of dengue protein with the maximum binding energy as -7.35 kcal/mol. CONCLUSIONS: It is concluded that isolated andrographolide from the A. paniculata possess anti-dengue activity against dengue-2 virus as revealed from in vitro and in silico method. Due to lack of the vaccine and anti-viral agents, andrographolide extracted from A. paniculata play a major role to inhibit the dengue replication. Hence, it could be a source for drug design and help to reduce the dengue infection.

In-vitro and in silico activity of Cyamopsis tetragonoloba (Gaur) L. supercritical extract against the dengue-2 virus.

Our health and wealth are highly influenced by a number of viruses. Dengue is one of them having a global influence in absence of vaccines and antiviral. WHO suggested that the morbidity of dengue is increasing more than 6 times from 0.5 million in 2010 to over 3.34 million in 2016, following a sharp increase in 2019. The aim of the present study is to check the in vitro and in silico anti-dengue activity of Cyamopsis tetragonoloba supercritical extract in cell lines. The optimum yield of supercritical extract was obtained 0.13 g/10 g (1.3% w/w) at 40 °C temp and 15 MPa pressure and further characterized by GC-MS. The antiviral assay was performed on C6/36 cell lines with 100 copies of dengue-2 virus and maximum non-toxic dose (31.25 µg/ml) of supercritical extract and their effect was detected by real-time RT-PCR. This study revealed that C. tetragonoloba supercritical extract inhibited the dengue-2 virus (99.9%). GC-MS analysis of C. tetragonoloba supercritical extract showed the presence of 10 compounds. The major compounds identified were Hexadecanoic acid, 15-methyl-methyl ester (24.498%); 9,12-octadecadienoyl chloride, (z,z)- (23.718%); methyl dodecanoic acid (13.228%); methyl-stearate (8.696%); Tridecanoic acid, 12-methyl-, methyl-ester (8.426%), dodecanoic acid (6.102%). The study reveals that C. tetragonoloba can be exploited to develop an effective, inexpensive, and specific anti-dengue. The molecular docking study demonstrated the binding energy of 1,2-benzenedicarboxylic acid, bis(2-methylpropyl) ester (- 4.1 kcal/mol), 9,12-octadecadienoyl chloride (z,z) (- 4.0 kcal/mol) ligands were higher than others. It is concluded that C. tetragonoloba can play a major role to inhibit dengue-2 virus.

Anti-viral activity of Zingiber officinale (Ginger) ingredients against the Chikungunya virus.

Chikungunya is one of the highly infectious viral disease without vaccine and anti-viral. Aim of present study is to check the anti-chikungunya activities of Zingiber officinale (Ginger) in the animal cell culture model. The medicinal plant extract was prepared from Z. officinale rhizome. Median tissue culture infective dose (TCID50) of Chikungunya virus (CHIKV) and Maximum non-toxic dose (MNTD) of Z. officinale extract was determined in Vero cell-line on the basis of cell viability followed by MTT assay. In vitro anti-chikungunya activity was performed in Vero cell-line with MNTD and half of MNTD of Z. officinale medicinal plant extract. The anti-viral effect of Z. officinale was studied by observing the cytopathic effects and cell viability measured by MTT assay. Maximum non-toxic dose of Z. officinale plant extract was found 62.5 µg/ml. During anti-chikungunya experimentation, cell viability increased to 51.05% and 35.10%, when Vero cells were pre-treated with MNTD and half of MNTD of Z. officinale extract respectively. Similarly, in co-treatment, when MNTD, half of MNTD of Z. officinale and Median tissue culture infective dose CHIKV were inoculated simultaneously, then the viability of Vero cell-line was increases by 52.90% and 49.02% respectively. The rhizome extracts of Z. officinale have high potential to treat CHIKV. Medicinal plants and their metabolites are most important sources of antimicrobial and can be utilized for the development of new drugs. In view of the rapid expansion of CHIKV at the global level, there is an urgent need to develop newer anti-chikungunya drugs.

The Indian perspective of COVID-19 outbreak.

The emerging infection of COVID-19 was initiated from Wuhan, China, have been spread to more than 210 countries around the globe including India. The clinical symptoms of COVID-19 are very similar to other respiratory viruses. The number of laboratory-confirmed cases and associated deaths are increasing regularly in various parts of the World. Seven coronaviruses (229E, NL63, OC43, HKU1, SARS, MERS and, COVID-19) can naturally infect human beings. Out of these four (229E-CoV, NL63-CoV, OC43-CoV, HKU1-CoV) are responsible for mild upper respiratory infections, while SARS-CoV, MERS-CoV, and COVID-19 are well known for their high mortality. Few mild strains of coronaviruses are circulating in India but there is no evidence of SARS and MERS outbreaks. The COVID-19 is an emerging viral infection responsible for pandemics. Fortunately, the mortality of COVID-19 is low as compared with SARS and MERS, the majority of its cases are recovered. The death toll of COVID-19 is high even after its low mortality because COVID-19 causes a pandemic while SARS-CoV and MERS-CoV cause epidemics only. COVID-19 influenced the large segments of the world population, which led to a public health emergency of international concern, putting all health organizations on high alert. COVID-19 is the first coronavirus after Spanish Flu 1918-1919, who has extremely influenced the health system, economy, and psychology of India. The present study review is on the general continent, virology, pathogenesis, global epidemiology, clinical presentation, diagnosis, treatment and control of COVID-19 with the reference to India.

Zika virus: an emerging challenge to public health worldwide.

Zika virus (ZIKV) is a mosquito-borne virus that was first isolated from Zika forest, Uganda, in 1947. Since its inception, major and minor outbreaks have been documented from several parts of world. Aedes spp. mosquitoes are the primary vectors of ZIKV, but the virus can also be transmitted through sexual practices, materno-fetal transmission, and blood transfusion. The clinical presentations of symptomatic ZIKV infections are similar to dengue and chikungunya, including fever, headache, arthralgia, retro-orbital pain, conjunctivitis, and rash. ZIKV often causes mild illness in the majority of cases, but in some instances, it is linked with congenital microcephaly and autoimmune disorders like Guillain-Barré syndrome. The recent Indian ZIKV outbreak suggests that the virus is circulating in the South East Asian region and may cause new outbreaks in future. At present, no specific vaccines or antivirals are available to treat ZIKV, so management and control of ZIKV infections rely mostly on preventive measures.

Phylogenetic analysis of the hemagglutinin gene of influenza A(H1N1)pdm09 and A(H3N2) virus isolates from Haryana, India.

Influenza A viruses are highly adaptable and are the main pathogen behind winter time morbidity. The present study reports the molecular and phylogenetic characterization of A(H1N1)pdm09 and H3N2 isolates from Haryana, India during 2015 influenza outbreak. A total of 144 nasopharyngeal samples were collected from Post Graduate Institute of Medical Sciences, Rohtak, Haryana, India form September 2014 to February 2016. The samples were screened for influenza A subtypes; A(H1N1)pdm09 and H3N2 by using real-time RT-PCR. Virus isolation and hemagglutinin gene sequencing studies were performed for selected positive samples. Out of 24 (16.6%) Influenza A positive samples, 13 (54.2%) and 11 (45.8%) were subtyped into A(H1N1)pdm09 and H3N2, respectively by real-time RT-PCR. Genetic analysis of A(H1N1)pdm09 isolates revealed the presence of key mutations (P100S, S202T and S220T) in HA gene as compare to reference strain A/California/07/2009 and these isolates were grouped in clade 6B.1 and 6B.2. All A(H3N2) isolates were clustered in clade 3C.2a and revealed specific amino acid substitutions of N161S and P214S in their HA genes in comparison to the reference strain A/Texas/50/2012. The HA gene sequences of all isolates showed 97-98% of nucleotide sequence similarity with their respective reference strains. Influenza A(H1N1)pdm09 and H3N2 isolates were drifted significantly from their respective vaccines strains of 2015-2016 and were more closely related to recommended vaccine strains for flu season 2017-2018. The study supports the need of routine influenza surveillance and continuous monitoring of the genetic changes in the major antigenic sites of these viruses.

Emerging trends of Nipah virus: A review.

Since emergence of the Nipah virus (NiV) in 1998 from Malaysia, the NiV virus has reappeared on different occasions causing severe infections in human population associated with high rate of mortality. NiV has been placed along with Hendra virus in genus Henipavirus of family Paramyxoviridae. Fruit bats (Genus Pteropus) are known to be natural host and reservoir of NiV. During the outbreaks from Malaysia and Singapore, the roles of pigs as intermediate host were confirmed. The infection transmitted from bats to pigs and subsequently from pigs to humans. Severe encephalitis was reported in NiV infection often associated with neurological disorders. First NiV outbreak in India occurred in Siliguri district of West Bengal in 2001, where direct transmission of the NiV virus from bats-to-human and human-to-human was reported in contrast to the role of pigs in the Malaysian NiV outbreak. Regular NiV outbreaks have been reported from Bangladesh since 2001 to 2015. The latest outbreak of NiV has been recorded in May, 2018 from Kerala, India which resulted in the death of 17 individuals. Due to lack of vaccines and effective antivirals, Nipah encephalitis poses a great threat to public health. Routine surveillance studies in the infected areas can be useful in detecting early signs of infection and help in containment of these outbreaks.

Green synthesis of silver nanoparticles from medicinal plants and evaluation of their antiviral potential against chikungunya virus.

The exploration of nanoscale materials for their therapeutic potential against emerging and re-emerging infections has been increased in recent years. Silver nanoparticles (AgNPs) are known to possess antimicrobial activities against different pathogens including viruses and provide an excellent opportunity to develop new antivirals. The present study focused on biological synthesis of AgNPs from Andrographis paniculata, Phyllanthus niruri, and Tinospora cordifolia and evaluation of their antiviral properties against chikungunya virus. Synthesized plants AgNPs were characterized to assess their formation, morphology, and stability. The cytotoxicity assays in Vero cells revealed that A. paniculata AgNPs were most cytotoxic with maximum non-toxic dose (MNTD) value of 31.25 µg/mL followed by P. niruri (MNTD, 125 µg/mL) and T. cordifolia AgNPs (MNTD, 250 µg/mL). In vitro antiviral assay of AgNPs based on degree of inhibition of cytopathic effect (CPE) showed that A. paniculata AgNPs were most effective, followed by T. cordifolia and P. niruri AgNPs. The results of antiviral assay were confirmed by cell viability test using 3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyltetrazolium bromide (MTT) dye, which revealed that A. paniculata AgNPs inhibited the virus to a maximum extent. The cell viability of CHIKV-infected cells significantly increased from 25.69% to 80.76 and 66.8%, when treated with A. paniculata AgNPs at MNTD and ½MNTD, respectively. These results indicated that use of plants AgNPs as antiviral agents is feasible and could provide alternative treatment options against viral diseases which have no specific antiviral or vaccines available yet.