SCOPE: Surveillance of COVID-19 in pregnancy- results of a multicentric ambispective case-control study on clinical presentation and maternal outcomes in India between April to November 2020.

OBJECTIVE: To determine the clinical manifestations, risk factors, treatment modalities and maternal outcomes in pregnant women with lab-confirmed COVID-19 and compare it with COVID-19 negative pregnant women in same age group. DESIGN: Multicentric case-control study. DATA SOURCES: Ambispective primary data collection through paper-based forms from 20 tertiary care centres across India between April and November 2020. STUDY POPULATION: All pregnant women reporting to the centres with a lab-confirmed COVID-19 positive result matched with controls. DATA QUALITY: Dedicated research officers extracted hospital records, using modified WHO Case Record Forms (CRF) and verified for completeness and accuracy. STATISTICAL ANALYSIS: Data converted to excel files and statistical analyses done using STATA 16 (StataCorp, TX, USA). Odds ratios (ORs) with 95% confidence intervals (CI) estimated using unconditional logistic regression. RESULTS: A total of 76,264 women delivered across 20 centres during the study period. Data of 3723 COVID positive pregnant women and 3744 age-matched controls was analyzed. Of the positive cases 56·9% were asymptomatic. Antenatal complications like preeclampsia and abruptio placentae were seen more among the cases. Induction and caesarean delivery rates were also higher among Covid positive women. Pre-existing maternal co-morbidities increased need for supportive care. There were 34 maternal deaths out of the 3723(0.9%) positive mothers, while covid negative deaths reported from all the centres were 449 of 72,541 (0·6%). CONCLUSION: Covid-19 infection predisposed to adverse maternal outcomes in a large cohort of Covid positive pregnant women as compared to the negative controls.

Postbiotic production: harnessing the power of microbial metabolites for health applications.

Postbiotics, which are bioactive substances derived from the metabolic processes of beneficial microbes, have received considerable attention in the field of microbiome science in recent years, presenting a promising path for exploration and innovation. This comprehensive analysis looks into the multidimensional terrain of postbiotic production, including an extensive examination of diverse postbiotic classes, revealing their sophisticated mechanisms of action and highlighting future applications that might significantly affect human health. The authors thoroughly investigate the various mechanisms that support postbiotic production, ranging from conventional fermentation procedures to cutting-edge enzyme conversion and synthetic biology approaches. The review, as an acknowledgment of the field's developing nature, not only highlights current achievements but also navigates through the problems inherent in postbiotic production. In order to successfully include postbiotics in therapeutic interventions and the production of functional food ingredients, emphasis is given to critical elements, including improving yields, bolstering stability, and assuring safety. The knowledge presented herein sheds light on the expanding field of postbiotics and their potential to revolutionize the development of novel therapeutics and functional food ingredients.

Repurposing of the herbal formulations: molecular docking and molecular dynamics simulation studies to validate the efficacy of phytocompounds against SARS-CoV-2 proteins.

Herbal formulations mentioned in traditional medicinal texts were investigated for in silico effect against SARS-COV-2 proteins involved in various functions of a virus such as attachment, entry, replication, transcription, etc. To repurpose and validate polyherbal formulations, molecular docking was performed to study the interactions of more than 150 compounds from various formulations against the SARS-CoV-2 proteins. Molecular dynamics (MD) simulation was performed to evaluate the interaction of top scored ligands with the various receptor proteins. The docking results showed that Liquiritic acid, Liquorice acid, Terchebulin, Glabrolide, Casuarinin, Corilagin, Chebulagic acid, Neochebulinic acid, Daturataturin A, and Taraxerol were effective against SARS-COV-2 proteins with higher binding affinities with different proteins. Results of MD simulations validated the stability of ligands from potent formulations with various receptors of SARS-CoV-2. Binding free energy analysis suggested the favourable interactions of phytocompounds with the recpetors. Besides, in silico comparison of the various formulations determined that Pathyadi kwath, Sanjeevani vati, Yashtimadhu, Tribhuvan Keeratiras, and Septillin were more effective than Samshamni vati, AYUSH-64, and Trikatu. Polyherbal formulations having anti-COVID-19 potential can be used for the treatment with adequate monitoring. New formulations may also be developed for systematic trials based on ranking from these studies.Communicated by Ramaswamy H. Sarma.

Identifying the Molecular Targets of an Anti-pathogenic Hydroalcoholic Extract of Punica granatum Peel Against Multidrug-resistant Serratia marcescens.

BACKGROUND: Antibiotic-resistant members of the family Enterobacteriaceae are among the serious threats to human health globally. This study reports the anti-pathogenic activity of Punica granatum peel extract (PGPE) against a multi-drug resistant, beta-lactamase producing member of this family i.e. Serratia marcescens. OBJECTIVE: This study aimed at assessing the anti-pathogenic activity of PGPE against the gramnegative bacterial pathogen S. marcescens and identifying the molecular targets of this extract in the test bacterium. METHODS: Effect of PGPE on S. marcescens growth and quorum sensing (QS)-regulated pigment production was assessed through broth dilution assay. In vivo anti-infective and prophylactic activity of PGPE was assessed employing the nematode worm Caenorhabditis elegans as a model host. Differential gene expression in PGPE-exposed S. marcescens was studied through a whole transcriptome approach. RESULTS: PGPE was able to modulate QS-regulated pigment production in S. marcescens without exerting any heavy growth-inhibitory effect at concentrations as low as ≥2.5 µg/mL. It could attenuate the virulence of the test bacterium towards the worm host by 22-42% (p≤0.01) at even lower concentrations (≥0.5 µg/mL). PGPE also exerted a post-extract effect on S. marcescens. This extract was found to offer prophylactic benefit too, to the host worm, as PGPE-pre-fed worms scored better (34-51%; p≤0.001) survival in face of subsequent bacterial attack. Differential gene expression analysis revealed that PGPE affected the expression of a total of 66 genes in S. marcescens by ≥1.5 fold. CONCLUSION: The anti-virulence effect of PGPE against S. marcescens is multifaceted, affecting stress-response machinery, efflux activity, iron homeostasis, and cellular energetics of this bacterium notably. Among the major molecular targets identified in this study are LPS export transporter permease (LptF), t-RNA pseudouridine synthase (TruB), etc.

Anti-infective potential of a quorum modulatory polyherbal extract (panchvalkal) against certain pathogenic bacteria.

BACKGROUND: In view of the gravity of the problem of antimicrobial resistance among pathogenic bacteria against conventional bactericidal agents, investigation on alternative approaches to combat bacterial infections is warranted. OBJECTIVE: Current study aimed at investigating anti-infective potential of a polyherbal ayurvedic formulation namely panchvalkal against three different pathogenic bacteria. MATERIALS AND METHODS: The panchvalkal formulation available as Pentaphyte P5® was tested for its possible in vitro quorum-modulatory potential against Chromobacterium violaceum, Serratia marcescens, and Staphylococcus aureus through broth dilution assay. Invivo efficacy was demonstrated employing Caenorhabditis elegans as the model host for test pathogens. RESULTS: This formulation was found to exert quorum-modulatory effect on C. violaceum, S. marcescens, and S. aureus at 250-750 µg/ml. Besides altering production of the quorum sensing-regulated pigments in these bacteria, the test formulation also had in vitro effect on antibiotic susceptibility, catalase activity and haemolytic potential of the pathogens. Invivo assay confirmed the protective effect of this panchvalkal formulation on C. elegans, when challenged with the pathogenic bacteria. Repeated exposure of S. aureus to panchvalkal did not induce resistance in this bacterium. CONCLUSION: To the best of our awareness, this the first report on quorum-modulatory potential of panchvalkal formulation, validating the anti-infective potential and moderate prebiotic property of this polyherbal preparation.

The Anti-infective Potential of Hydroalcoholic Extract of Phyllanthus emblica Seeds Against Selected Human-pathogenic Bacteria.

INTRODUCTION: In the context of the global threat of antimicrobial resistance (AMR) among bacterial pathogens against conventional bactericidal antibiotics, investigation on complementary/ alternative approaches to manage bacterial infections is warranted. The present study aimed at investigating the anti-pathogenic potential of Phyllanthus emblica seed extract (PESE) against four different pathogenic bacteria. METHODS: Hydroalcoholic extract of P. emblica seeds was tested for its possible in vitro quorummodulatory potential against Chromobacterium violaceum, Serratia marcescens, Pseudomonas aeruginosa, and Staphylococcus aureus through broth dilution assay. In vivo efficacy of PESE was assayed employing Caenorhabditis elegans as the model host for these four pathogens. RESULTS: PESE was found to exert in vitro quorum-modulatory effect on C. violaceum, S. marcescens, P. aeruginosa, and S. aureus at ≥50 µg/mL. This extract could curb the haemolytic activity of all the four test bacteria by 23-65%, inhibit biofilm formation, and was also able to modulate their antibiotic susceptibility (AS) and catalase activity. Susceptibility of P. aeruginosa and S. aureus to lysis by human serum was enhanced under the influence of this extract by 23% and 49%, respectively. Repeated exposure of both these notorious pathogens to PESE did not induce resistance in them. In vivo assay confirmed the anti-virulence effect of this extract in the C. elegans host, wherein the nematode host challenged with the PESE-treated pathogenic bacteria scored better survival. PESE also displayed notable prebiotic potential by promoting the growth of three probiotic strains. CONCLUSION: To the best of our awareness, this is the first report on the quorum-modulatory potential of P. emblica seed extract, validating its anti-infective potential and prebiotic property.

Supernatants of the Probiotic Bacterial Cultures at sub-MIC Levels Attenuate Virulence of Pathogenic Bacteria Towards the Model Host Caenorhabditis elegans.

OBJECTIVE: This study assessed the anti-pathogenic potential of culture supernatants from three probiotic strains viz. Lactobacillus plantarum, Bifidobacterium bifidum, and Enterococcus faecium against five different gram-positive and gram-negative pathogenic bacteria. METHODS: The effect of probiotic culture supernatants on growth and production of quorum sensing (QS)-regulated pigments was assessed through broth dilution assay. In vivo anti-infective efficacy of these supernatants was evaluated by challenging the model nematode host Caenorhabditis elegans with pathogenic bacteria pre-treated with probiotic culture supernatants, and worm survival was monitored over a period of 8 days. RESULTS: All the probiotic culture supernatants (at 5-10 %v/v) exhibited bactericidal activity against four of the test pathogens (including three multi-drug resistant gram-negative bacteria) and they (at ≥ 1%v/v) could also modulate QS in pathogenic bacteria. Pre-treatment with culture supernatants from all the three probiotic strains were able to attenuate virulence of four of the test pathogens towards C. elegans. Worms challenged with supernatant-pre-treated pathogens recorded 75-100% better survival than those challenged with pathogens receiving no such pretreatment. Virulence-attenuating effect of the culture supernatants was also carried forward to daughter populations of the supernatant-treated parent pathogens. Lactic acid seemed to contribute notably towards anti-virulence activity of the culture supernatants, but acidic pH did not seem to be important for such activity. CONCLUSION: Culture supernatants of probiotic strains used in this study can be said to possess appreciable virulence-attenuating potential. Further investigation for characterization of these supernatants and identification of the bioactive constituents is warranted. Elucidation of the molecular basis associated with the anti-pathogenic potential of these supernatants may lead to the identification of novel targets in pathogenic bacterial populations.

Anti-infective efficacy of Psidium guajava L. leaves against certain pathogenic bacteria.

Water extracts of Psidium guajava leaves prepared by three different extraction methods were compared with respect to their anti-infective activity against Pseudomonas aeruginosa and Staphylococcus aureus in the nematode host Caenorhabditis elegans. The water extract prepared by Microwave Assisted Extraction method was found to have better anti-infective activity, and its activity was further compared with hydroalcoholic extract prepared using the same extraction method against five different pathogenic bacteria. Both these extracts could attenuate virulence of P. aeruginosa, S. aureus, Serratia marcescens, and Chromobacterium violaceum, towards C. elegans. Anti-infective efficacy of P. guajava leaf extract seems partly to stem from its quorum-modulatory property, as it could modulate production of quorum sensing-regulated pigments in all the susceptible bacteria.

Anti-infective potential of hydroalcoholic extract of Punica granatum peel against gram-negative bacterial pathogens.

Background:Punica granatum extracts have been prescribed in traditional medicine for management of a variety of disease conditions including microbial infections. Generation of scientific evidence for validation of P. granatum peel extract's anti-pathogenic efficacy is required. Methods: Hydroalcoholic extract of P. granatum peel (PGPE), prepared by microwave assisted extraction method was evaluated for its quorum-modulatory potential against two different human-pathogenic bacteria viz. Chromobacterium violaceum and Pseudomonas aeruginosa. Results: This extract was able to modulate in vitro production of quorum sensing-regulated pigments in both these test bacteria at ≥5 µg/ml. Virulence traits of P. aeruginosa like haemolytic activity, and biofilm formation were negatively affected by the test extract, and it also made P. aeruginosa more susceptible to lysis by human serum. Antibiotic susceptibility of both test bacteria was modulated owing to pre-treatment with PGPE. Exposure of these test pathogens to PGPE (≥0.5 µg/ml) effectively reduced their virulence towards the nematode Caenorhabditis elegans. Repeated subculturing of P. aeruginosa on PGPE-supplemented growth medium did not induce resistance to PGPE in this notorious pathogen, and this extract was also found to exert a post-extract effect on P. aeruginosa. Individual constituent phytocompounds of PGPE were found to be less efficacious than the whole extract. PGPE seemed to interfere with the signal-response machinery of P. aeruginosa and C. violaceum. PGPE also exhibited notable prebiotic potential by promoting growth of probiotic strains- Bifidobacterium bifidum and Lactobacillus plantarum at ≤50 µg/ml. Conclusions: This study indicates PGPE to be an effective antipathogenic and prebiotic preparation, and validates its therapeutic use mentioned in traditional medicine. This study also emphasizes the need for testing any bioactive extract at broadest possible concentration range, particularly in vivo, so that an accurate picture of dose-response relationship can emerge.

Antipathogenic Potential of a Polyherbal Wound-Care Formulation (Herboheal) against Certain Wound-Infective Gram-Negative Bacteria.

This study investigated antipathogenic efficacy of a polyherbal wound-healing formulation Herboheal against three multidrug-resistant strains of gram-negative bacterial pathogens associated with wound infections. Herboheal was evaluated for its quorum-modulatory potential against three different human-pathogenic bacteria, first in vitro through the broth dilution assay and then in vivo in the model host Caenorhabditis elegans. Herboheal at ≥0.1% v/v was able to inhibit (19-55%) in vitro production of quorum sensing-regulated pigments in all these bacteria and seemed to interfere with bacterial quorum sensing by acting as a signal-response inhibitor. This formulation could compromise haemolytic activity of all three bacteria by ∼18-69% and induced their catalase activity by ∼8-21%. Herboheal inhibited P. aeruginosa biofilm formation up to 40%, reduced surface hydrophobicity of P. aeruginosa cells by ∼9%, and also made them (25%) more susceptible to lysis by human serum. Antibiotic susceptibility of all three bacteria was modulated owing to pretreatment with Herboheal. Exposure of these test pathogens to Herboheal (≥0.025% v/v) effectively reduced their virulence towards the nematode Caenorhabditis elegans. Repeated subculturing of P. aeruginosa on the Herboheal-supplemented growth medium did not induce resistance to Herboheal in this mischievous pathogen, and this polyherbal extract was also found to exert a post-extract effect on P. aeruginosa, wherein virulence of the Herboheal-unexposed daughter cultures, of the Herboheal-exposed parent culture, was also found to be attenuated. Overall, this study indicates Herboheal formulation to be an effective antipathogenic preparation and validates its indicated traditional therapeutic use as a wound-care formulation.

Validation of the anti-infective potential of a polyherbal 'Panchvalkal' preparation, and elucidation of the molecular basis underlining its efficacy against Pseudomonas aeruginosa.

BACKGROUND: A Panchvalkal formulation (Pentaphyte P-5®) mentioned in ancient texts of Indian traditional medicine was investigated for its anti-infective potential against Pseudomonas aeruginosa. METHODS: Effect of the test formulation on bacterial growth and pigment production was evaluated by broth dilution assay. In vivo efficacy was evaluated using Caenorhabditis elegans as the model host. Whole transcriptome approach was taken to study the effect of test formulation on bacterial gene expression. RESULTS: This formulation in vitro was found to be capable of affecting quorum sensing (QS)-regulated traits (pyocyanin, pyoverdine, biofilm) of Pseudomonas aeruginosa. In combination with antibiotics, it enhanced susceptibility of the test bacterium to antibiotics like cephalexin and tetracycline. Effect of Panchvalkal formulation (PF) on QS-regulated traits of P. aeruginosa was not reversed even after repeated exposure of the bacterium to PF. In vivo efficacy of PF was demonstrated employing Caenorhabditis elegans as the model host, wherein PF-treated bacteria were able to kill lesser worms than their extract-unexposed counterparts. Whole transcriptome study revealed that approximately 14% of the P. aeruginosa genome was expressed differently under the influence of PF. CONCLUSIONS: Major mechanisms through which Panchvalkal seems to exert its anti-virulence effect are generation of nitrosative and oxidative stress, and disturbing iron and molybdenum homeostasis, besides interfering with QS machinery. This study is a good demonstration of the therapeutic utility of the 'polyherbalism' concept, so common in ayurved. It also demonstrates utility of the modern 'omics' tools for validating the traditional medicine i.e. ayuromics.

Anti-Pathogenic Efficacy and Molecular Targets of a Polyherbal Wound- Care Formulation (Herboheal) Against Staphylococcus aureus.

BACKGROUND: A polyherbal formulation (Herboheal) traditionally indicated for woundcare was investigated for its anti-virulence potential against the notorious pathogen Staphylococcus aureus. OBJECTIVE: This study aimed at evaluating anti-virulence potential of Herboheal formulation against S. aureus in vitro as well as in vivo, followed by studying its effect on target bacterium's gene expression at the whole transcriptome level. METHODS: In vitro efficacy of the test formulation was evaluated using broth dilution assay, whereas in vivo efficacy was assayed employing the nematode Caenorhabditis elegans as the model host. Molecular targets of the test formulation in S. aureus were elucidated through whole transcriptome analysis. RESULTS: This formulation could exert inhibitory effect on bacterial growth and quorum sensingregulated pigment (staphyloxanthin) production at ≥ 0.025% v/v. It not only could inhibit S. aureus biofilm formation, but also eradicated pre-formed biofilm effectively. This formulation could modulate antibiotic susceptibility of S. aureus, enhanced its susceptibility to human serum heavily, while compromising its haemolytic potential. Herboheal-treated bacteria expressed notably lesser virulence towards the nematode worm Caenorhabditis elegans. Even repeated exposure of S. aureus to this polyherbal formulation did not give rise to resistant phenotype. Whole transcriptome analysis revealed genes associated with hemolysis, virulence, enzyme activity, transport, basic cellular processes, quorum sensing, and transcriptional regulators as the major targets of Herboheal in S. aureus. CONCLUSION: This study validates the traditional use of Herboheal formulation in wound-care by demonstrating its efficacy against one of the pathogenic bacteria most commonly involved in wound infections.

Prophylactic potential of a Panchgavya formulation against certain pathogenic bacteria.

A Panchgavya preparation was evaluated for its prophylactic efficacy against bacterial infection, employing the nematode worm Caenorhabditis elegans as a model host. Worms fed with the Panchgavya preparation prior to being challenged with pathogenic bacteria had a better survival rate against four out of five test bacterial pathogens, as compared to the control worms. Panchgavya feeding prior to bacterial challenge was found to be most effective against Staphylococcus aureus, resulting in 27% (p=0.0001) better worm survival. To the best of our awareness, this is the first report demonstrating in vivo prophylactic efficacy of Panchgavya mixture against pathogenic bacteria.

Importance of Selecting Appropriate Wavelength, While Quantifying Growth and Production of Quorum Sensing Regulated Pigments in Bacteria.

BACKGROUND: Pigment production is regulated by quorum-sensing (QS) in certain bacteria which are being widely used as model organisms in different QS labs. This paper emphasizes importance of selecting an appropriate wavelength for quantification of bacterial growth and pigmentation. While screening different natural/synthetic preparations for their possible QSmodulating potential, it becomes very much necessary to establish that the observed effect is truly QS-associated, and not falsely inflated owing to inaccurate quantification of bacterial cell density/ pigment intensity. METHODS: Pigments were extracted in suitable organic solvents, whereas quantification of bacterial growth and extracted pigments was done photometrically. RESULTS: Findings reported in this paper, suggest that while quantifying cell density in a pigmented bacterial suspension, such a wavelength (e.g. 764 nm) should be selected at which pigment interference is either absent or minimum. Additionally, importance of appropriate dilution of the bacterial cell suspensions, prior to photometric measurement has been highlighted. CONCLUSION: This work indicates that while working with pigmented bacteria, it is important to pay attention to the absorption spectrum of the pigment(s) involved, and also to dilute the dense bacterial suspensions appropriately prior to measuring optical density, so as to avoid any major deviation of OD from the proportionality to the cell density. Besides presenting the experimental data in this paper, patents regarding measurement of cell growth, as well as those indicating the potential of commercialization of various aspects of QS research have been mentioned.