CRISPR/Cas genome editing in plants: Dawn of Agrobacterium transformation for recalcitrant and transgene-free plants for future crop breeding

Genome editing tools based on CRISPR/Cas system have been posed to solve many issues in agriculture and improve food production. Genetic engineering by Agrobacterium-mediated transformation has helped to impart specific traits straightaway in many crops. Many GM crops have also reached the field for commercial cultivation. Genetic engineering requires mostly a transformation protocol often mediated by Agrobacterium to insert a specific gene at a random locus. Genome editing with CRISPR/Cas system is a more precise technique for the targeted modification of genes/bases in the host plant genome. Unlike the conventional transformation system, wherein elimination of marker/foreign gene was possible only post-transformation, CRISPR/Cas system could generate transgene-free plants by delivering CRISPR/Cas reagents such as the Cas protein and guide RNAs gRNA(s) preassembled to form ribonucleoproteins (RNPs) into plant cells. CRISPR reagent delivery might be helpful to overcome issues with plants that are recalcitrant to Agrobacterium transformation and the legal hurdles due to the presence of the foreign gene. More recently, the grafting of wild-type shoots to transgenic donor rootstocks developed by the CRISPR/Cas system has reported transgene-free genome editing. CRISPR/Cas system also requires only a small piece of gRNA besides Cas9 or other effectors to target a specific region in the genome. So this system has been projected to be a key contributor to future crop breeding. In this article, we recap the main events of plant transformation, compare the difference between genetic transformation and CRISPR/Cas-mediated genome editing, and draw insights into the future application of the CRISPR/Cas system.

In vitro growth inhibitory effect of selected 18β-glycyrrhetinic acid esters on Theileriaannulata

Glycyrrhetinic acid (GA) is one of the important Pentacyclic Triterpenoids (PT) found in the roots of licorice. This study aimed to evaluate the in vitro growth inhibitory effect of 18β-GA (18β-Glycyrrhetinic acid) and C-30 esters against Theileria annulata, the causative agent of Tropical Bovine Theileriosis. C-30 esters of 18β-GA were synthesized and their structures were elucidated using spectroscopy. The pharmacodynamic properties of 18β-GA and its C-30 esters were predicted using DataWarrior and Swiss ADME tools. Cattle isolates of T. annulata schizont-infected bovine lymphoblastoid cells were cultured using standard conditions and the growth inhibitory effect of GA and its esters were evaluated using MTT assay. The isopropyl ester of 18β-GA (GI₅₀- 1.638 μM; R²- 0.818) showed improved anti-theileriosis efficacy than other 18β-GA derivatives. The propyl (GI₅₀ - 5.549 μM), ethyl (GI₅₀ - 5.638 μM), and benzyl (GI₅₀ - 7.431 μM) esters also showed considerable inhibitory effect. The GI₅₀ value for 18β-GA was recorded as 6.829 μM. This study throws light on the usefulness of 18β-GA and its esters for the treatment of Tropical Bovine Theileriosis.

Improving abiotic stress tolerance in sorghum: focus on the nutrient transporters and marker-assisted breeding

Identification of molecular markers and characterization of nutrient transporters could help to improve the tolerance under abiotic and low nutrient stresses in sorghum ensuring higher yield to conserve food security Sorghum is an important cereal crop delivering food and energy security in the semi-arid tropics of the world. Adverse climatic conditions induced by global warming and low input agriculture system in developing countries demand for the improvement of sorghum to tolerate various abiotic stresses. In this review, we discuss the application of marker-assisted breeding and nutrient transporter characterization studies targeted towards improving the tolerance of sorghum under drought, salinity, cold, low phosphate and nitrogen stresses. Family members of some nutrient transporters such as nitrate transporter (NRT), phosphate transporter (PHT) and sulphate transporter (SULTR) were identified and characterized for improving the low nutrient stress tolerance in sorghum. Several quantitative trait loci (QTL) were identified for drought, salinity and cold stresses with an intention to enhance the tolerance of sorghum under these stresses. A very few QTL and nutrient transporters have been identified and validated under low nitrogen and phosphorus stresses compared to those under drought, salinity and cold stresses. Marker-assisted breeding and nutrient transporter characterization have not yet been attempted in sorghum under other macro- and micro-nutrient stresses. We hope this review will raise awareness among plant breeders, scientists and biotechnologists about the importance of sorghum and need to conduct the studies on marker-assisted breeding and nutrient transporter under low nutrient stresses to improve the sorghum production.

First record of the Afghan Poplar Hawkmoth Laothoe witti Eitschberger et al., 1998 (Sphingidae: Smerinthinae) from India: a notable range extension for the genus

Laothoe witti Eitschberger, Danner & Surholt, 1998, the Afghan Poplar Hawkmoth, was first described from Afghanistan, after which there have only been isolated reports of the species within the Palaearctic region.  Only five species have so far been reported under the genus Laothoe with no evidence of the occurrence of the genus Laothoe in India till date.  Here we provide information about the record of L. witti from Kashmir that establish first evidence of the occurrence of this species in India, extending the range of the genus Laothoe into the Indian sub-continent.

Expression of PHT1 family transporter genes contributes for low phosphate stress tolerance in foxtail millet (Setaria italica) genotypes

This is a first comprehensive study to analyze the 12 PHT1 family phosphate transporter genes in 20 foxtail millet genotypes for the improvement of millets and other crops for phosphate use efficiency. Phosphorus (P), absorbed from soil solutions as inorganic phosphate (Pi), is a limiting nutrient for plant growth and yield. Twenty genotypes of foxtail millet (Setaria italica) with contrasting degree of growth and Pi uptake responses under low Pi (LP) and high Pi (HP) supply were chosen based on a previous study. To gain molecular insights, expression dynamics of 12 PHosphate Transporter 1 (PHT1) family (SiPHT1;1 to 1;12) genes were analyzed in these 20 genotypes and compared with their Pi and total P (TP) contents. SiPHT1;1, 1;2, 1;3 and 1;8 genes were expressed in shoot tissues of three (ISe 1209, ISe 1305 and Co-6) of the LP best performing genotypes (LPBG); however, they were expressed in only one of the LP worst performing genotype (LPWG) (ISe 748). More importantly, this is correlating with higher shoot Pi and TP contents of the LPBG compared to LPWG. Apart from this condition, expression of SiPHT1 genes and their Pi and TP contents do not correlate directly for many genotypes in other conditions; genotypes with low Pi and TP contents induced more SiPHT1 genes and vice versa. Promoter analysis revealed that genotype ISe 1888 with a high level of SiPHT1;8 expression possesses two additional root box motifs compared to other genotypes. The PHT1 family genes seem to play a key role for LP stress tolerance in foxtail millet and further studies will help to improve the P-use efficiency in foxtail millet and other cereals.

Phenotypic responses of foxtail millet (Setaria italica) genotypes to phosphate supply under greenhouse and natural field conditions

Food insecurity is a looming threat for the burgeoning world population. Phosphorus (P), which is absorbed from soil as inorganic phosphate (Pi), is an essential macronutrient for the growth of all agricultural crops. This study reports phenotype analysis for P responses in natural field and greenhouse conditions, using 54 genotypes of foxtail millet (Setaria italica) representing wide geographic origins. The genotype responses were assessed in natural field conditions in two different seasons (monsoon and summer) under Pi-fertilized (P+) and unfertilized (P-) soil for eight above-ground traits. Enormous variations were seen among the genotypes in phenotypic responses for all the measured parameters under low P stress conditions. Variations were significant for plant height, leaf number and length, tillering ability and seed yield traits. Genotypes ISe 1234 and ISe 1541 were P+ responders, and the genotypes ISe 1181, ISe 1655, ISe 783 and ISe 1892 showed tolerance to low P for total seed yield. Genotypes that performed well under P- conditions were almost as productive as genotypes that performed well under P+ conditions suggesting some genotypes are well adapted to nutrient-poor soils. In the greenhouse, most of the genotypes produced changes in root architecture that are characteristic of P- stress, but to differing degrees. Significant variation was seen in root hair density and root hair number and in fresh and dry weight of shoot and root under P- stress. However, there was not much difference in the shoot and root total P and Pi levels of five selected high and low responding genotypes. We noticed contrasting responses in the greenhouse and natural field experiments for most of these genotypes. The leads from the study form the basis for breeding and improvement of foxtail millet for better Pi-use efficiency.

Antihyperlipidemic effect of iridoid glycoside deacetylasperulosidic acid isolated from the seeds of Spermacoce hispida L. - A traditional antiobesity herb

ETHNOBOTANICAL RELEVANCE

The interest on herbal health supplements for obesity is increasing globally. Our previous ethnobotanical survey in Tiruvallur district, Tamil Nadu, India indicated the use of Spermacoce hispida L. seeds for the treatment of obesity.

AIM OF THE STUDY

This study was aimed to validate the traditional claim and to identify the antihyperlipidemic principle in the seeds of Spermacoce hispida using bioassay guided fractionation method.

METHODS

Bioassay monitored fractionation of the aqueous extract from Spermacoce hispida seeds was carried out using triton WR 1339 induced hyperlipidemic animals. It yielded deacetylasperulosidic acid (DAA) as the active ingredient. Pharmacokinetic properties of DAA were predicted using DataWarrior and SwissADME tools. In vitro antiobesity and antihyperlipidemic effects of DAA were evaluated in 3T3L1 preadipocytes and HepG2 cells, respectively. The chronic antihyperlipidemic efficacy of DAA was evaluated in high fat diet fed rats.

RESULTS

DAA did not show any mutagenic and tumorigenic properties. It bound with PPARα with comparable ligand efficiency as fenofibrate. The treatment with DAA significantly lowered the proliferation of matured adipocytes, but not preadipocytes. The treatment of steatotic HepG2 cells with DAA significantly decreased the LDH leakage by 43.03% (P < 0.05) at 50 μM concentration. In triton WR 1339 induced hyperlipidemic animals, the treatment with 50 mg/kg dose significantly lowered the TC, TG and LDL-c levels by 40.27, 46.00 and 63.65% respectively. In HFD fed animals, the treatment at 10 mg/kg decreased BMI and AC/TC ratio without altering SRBG. It also improved serum lipid, transaminases and phosphatases levels of HFD fed animals. The treatment lowered adipocyte hypertrophy and steatosis of hepatocytes.

CONCLUSION

This preliminary report supported the traditional use of Spermacoce hispida for the treatment of obesity. Further detailed investigations on the long term safety, efficacy and molecular mode of action of Spermacoce hispida and DAA will throw more light on their usefulness for the management of obesity.

The down regulation of PTP1B expression and attenuation of disturbed glucose and lipid metabolism using Borassus flabellifer (L) fruit methanol extract in high fat diet and streptozotocin induced diabetic rats

Borassus flabellifer L. is a tall palm traditionally used for its stimulating, diuretic and anti-inflammatory activities; it is rich in fibers and various pharmacologically important secondary metabolites. This study was undertaken to evaluate the antidiabetic effects of Borassus flabellifer fruit methanol extract (BF-M) on diabetic rats induced with High Fat Diet (HFD)/streptozotocin (STZ). When BF-M (100 or 200 mg/kg) was administered for 21 days orally it led to a sharp decline in triglycerides, total cholesterol, free unsaturated fat, glucose-6-phosphate, fasting blood glucose and fructose 1,6 bisphosphatase in contrast to diabetic control. BF-M also downregulated Protein Tyrosine Phosphatase 1B. In vitro study showed the IC₅₀ value to be 23.98 μg/mL. BF-M significantly increased serum insulin, glycogen content, and body weight. Western blot analysis exhibited significant inhibition of PTP1B in pancreatic tissue which was confirmed by histology and immunohistological studies. GC-MS analysis revelaled that the presence of major compounds such as 5-hydroxymethylfurfural (47.56%), Guanosine (21.01%) and n-hecxadeconoic acid (25.14%) in BF-M. In short, BF-M exerted antidiabetic property by down regulating PTP1B expression, and eventually enhancing glucose stimulated insulin release; it also exhibited favorable effects in diabetes and its secondary complications.

Quantitative analysis of medicinal plants used to treat musculoskeletal ailments by non-institutionally trained siddha practitioners of Virudhunagar district, Tamil Nadu, India

Background

Siddha is one of the traditional medical systems of India; previous ethnobotanical survey in Virudhunagar district indicated a high consensus for treating musculoskeletal ailments.

Objectives

This study was aimed to quantitatively document the medicinal plants used to treat musculoskeletal ailments by non-institutionally trained siddha practitioners of Virudhunagar district, Tamil Nadu, India.

Materials and methods

This work was the outcome of free-list interviews conducted among 45 informants between April 2016 and January 2017. Sampling sufficiency was assessed by plotting Shannon–Wiener's index and cumulative number of UR. Informant consensus was assessed using Informant Consensus Factor (F_ic) and Informant Agreement Ratio (IAR).

Results

This study recorded the data regarding 116 plant species which were used to prepare 129 formulations; analysis of the data yielded 490 UR. Among these, 65.3% of UR dealt with internal applications and 34.6% dealt with external applications. In the case of internally used formulations, pain and general musculoskeletal ailments had high F_ic values. In the case of externally used formulations, headache and pain had high F_ic values.

Conclusion

Important species prescribed by the informants to treat various musculoskeletal ailments were: Azima tetracantha, Ricinus communis, Sesamum indicum, Moringa oleifera, Cardiospermum halicacabum (internal application), Calophyllum inophyllum, Justicia adhatoda, Curcuma longa, Calotropis gigantea, Zingiber officinale, Withania somnifera, Strychnos nux-vomica, Dodonaea viscosa (external application), Azadirachta indica, Clerodendrum phlomidis,Delonix elata, Pergularia daemia and Vitex negundo (internal and external applications). Robust studies on these local claims will help to improve the community healthcare and will yield some novel agents to treat musculoskeletal ailments.

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Siddha is one of major traditional medicinal systems of India.

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Non-institutional training is still major in siddha system of medicine.

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This survey documented the plants used to treat various musculoskeletal ailments.

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Though there were some scientific evidences; many local claims lack rigorous studies.

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Further studies will yield some useful clues for the management of various MSDs.

Swertiamarin, a natural steroid, prevent bone erosion by modulating RANKL/RANK/OPG signaling

Bone erosion is a central feature of rheumatoid arthritis (RA) that is characterized by the infiltration of the synovial lining by osteoclasts and lymphocytes. In the present study, swertiamarin a major secoiridoid glycoside was evaluated for anti-osteoclastogenic property to prevent bone erosion in Freund's complete adjuvant (FCA) induced in-vivo model, in-vitro osteoblast and osteoclasts as well as in co-culture system and in-silico molecular docking analysis. The swertiamarin treatment decreased the expression of TRAP, RANKL, and RANK levels and increased the levels of OPG levels significantly in both in vitro and in vivo models. In in vitro, the compound treatment significantly increased the cell proliferation and ALP levels in osteoblast cells; the high proliferation (153.8600±5.23%) and ALP release (165.6033±4.13%) were observed at 50μg/ml concentration of swertiamarin treatment. At the same time the treatment decreased the TRAP positive cells in osteoclast cells; the high reductions of TRAP positive cells (39.32±3.19%) were observed at 50μg/ml of swertiamarin treatment. The treatment modulated the levels of pro-inflammatory cytokines, MMPs and NF-κB levels in osteoblast and osteoclast co-culture system. In in silico analysis swertiamarin had affinity towards the proteins RANK, RANKL and OPG residues with low binding energy -4.5, -3.92 and -5.77kcal/mol respectively. Thus, the results of this study revealed the anti-osteoclastogenic activity of swertiamarin on the prevention of bone destruction.

Hepatoprotective effect of lawsone on rifampicin-isoniazid induced hepatotoxicity in in vitro and in vivo models

The Drug-induced liver injury is one of the common unfavourable impacts, which seriously affects any drug therapy. This study documented the hepatoprotective efficacy of lawsone, the major bioactive naphthoquinone present in Lawsonia inermis L. (Lythraceae) using in vitro and in vivo models. Lawsone was isolated from the leaves of L. inermis and its structure was confirmed using spectroscopic data. In-vitro antioxidant effect of lawsone was evaluated using ABTS assay. Hepatoprotective effect of lawsone was determined with RIF-INH treated HepG2 cells and Wistar rats. Administration of RIF-INH reduced the viability of the HepG2 cells and the treatment with lawsone significantly restored the viability of the cells even at lower concentration (7.5 μM). The other parameters such as the leakage of transaminases and MDA levels were also significantly reduced by the treatment with lawsone. Oral administration of lawsone to the animals did not show any toxicity up to 2 g/kg b.w. concentration. Treatment with lawsone to the RIF-INH administered animals significantly lowered the serum transaminases levels. The ratio of albumin to globulin was improved and the level of bilirubin was lowered. This study indicated the hepatoprotective effect of lawsone; detailed investigations will give deeper understanding of the application of lawsone for hepatoprotection.

A study on food-medicine continuum among the non-institutionally trained siddha practitioners of Tiruvallur district, Tamil Nadu, India

BACKGROUND

Medicinal properties of the food species are one of the poorly documented and important areas of ethnopharmacology. The present survey quantitatively documented the medicinal foods prescribed by the non-institutionally trained siddha practitioners of Tiruvallur district of Tamil Nadu.

METHODS

Field work was carried out between December 2014 and April 2017 using a questionnaire. The illnesses mentioned by the informants were grouped as illness categories on the basis of emic perceptions. Sufficiency of sampling of this survey was assessed by plotting the cumulative number of UR and Shannon-Wiener's index. The indices such as informant consensus factor (FIC), Index of Agreement on Remedies (IAR), and Cultural Food Significance Index (CFSI) were calculated.

RESULTS

This study documented 165 medicinal foods used by 82 non-institutionally trained siddha practitioners of Tiruvallur district, and 73.93% of these preparations were plant based. Among the animal taxa, 82.05% were represented by fish taxa. The illness category gastrointestinal ailments is the majorly cited illness category treated with plant-based formulations. The illness categories viz., gastrointestinal ailments, hemorrhoids, and neural ailments had high consensus under the group of plant-based medicinal foods. In animal-based medicinal foods, kapha ailments had gained 23.07% of UR. The illness categories such as bone fractures, male reproductive ailments, blood ailments, and anabolic had high FIC values.

CONCLUSIONS

Deeper studies on different dietary cultures of India may help to derive better interpretations on food-medicine continuum. This study identified some important claims such as the use of citron, pomegranate and Solanum americanum (gastrointestinal ailments), Abutilon indicum, onions and elephant foot yam (hemorrhoids), Boerhavia diffusa (urinary ailments), Moringa oleifera (anemia), Aloe vera (gynecological ailments), Eclipta prostrata (liver ailments), ivy gourd (diabetes), citron (hypertension), Centella asiatica (psychological ailments), spade nose shark (lactogogue), reticulate whipray (wheezing and bronchitis), Katelysia opima (impotence), Indian squid (anemia), and Indian oil sardine (anabolic). More studies on these claims will help identify novel functional foods to add to the field of medical nutrition therapy, with traditional brand identity. Robust studies on the documentation of the traditional knowledge on marine resources will yield a good database for various stakeholders and policy makers.

Identification of putative QTLs for seedling stage phosphorus starvation response in finger millet (Eleusine coracana L. Gaertn.) by association mapping and cross species synteny analysis

A germplasm assembly of 128 finger millet genotypes from 18 countries was evaluated for seedling-stage phosphorus (P) responses by growing them in P sufficient (Psuf) and P deficient (Pdef) treatments. Majority of the genotypes showed adaptive responses to low P condition. Based on phenotype behaviour using the best linear unbiased predictors for each trait, genotypes were classified into, P responsive, low P tolerant and P non-responsive types. Based on the overall phenotype performance under Pdef, 10 genotypes were identified as low P tolerants. The low P tolerant genotypes were characterised by increased shoot and root length and increased root hair induction with longer root hairs under Pdef, than under Psuf. Association mapping of P response traits using mixed linear models revealed four quantitative trait loci (QTLs). Two QTLs (qLRDW.1 and qLRDW.2) for low P response affecting root dry weight explained over 10% phenotypic variation. In silico synteny analysis across grass genomes for these QTLs identified putative candidate genes such as Ser-Thr kinase and transcription factors such as WRKY and basic helix-loop-helix (bHLH). The QTLs for response under Psuf were mapped for traits such as shoot dry weight (qHSDW.1) and root length (qHRL.1). Putative associations of these QTLs over the syntenous regions on the grass genomes revealed proximity to cytochrome P450, phosphate transporter and pectin methylesterase inhibitor (PMEI) genes. This is the first report of the extent of phenotypic variability for P response in finger millet genotypes during seedling-stage, along with the QTLs and putative candidate genes associated with P starvation tolerance.

Insert, remove or replace: A highly advanced genome editing system using CRISPR/Cas9

The clustered, regularly interspaced, short palindromic repeat (CRISPR) and CRISPR associated protein 9 (Cas9) system discovered as an adaptive immunity mechanism in prokaryotes has emerged as the most popular tool for the precise alterations of the genomes of diverse species. CRISPR/Cas9 system has taken the world of genome editing by storm in recent years. Its popularity as a tool for altering genomes is due to the ability of Cas9 protein to cause double-stranded breaks in DNA after binding with short guide RNA molecules, which can be produced with dramatically less effort and expense than required for production of transcription-activator like effector nucleases (TALEN) and zinc-finger nucleases (ZFN). This system has been exploited in many species from prokaryotes to higher animals including human cells as evidenced by the literature showing increasing sophistication and ease of CRISPR/Cas9 as well as increasing species variety where it is applicable. This technology is poised to solve several complex molecular biology problems faced in life science research including cancer research. In this review, we highlight the recent advancements in CRISPR/Cas9 system in editing genomes of prokaryotes, fungi, plants and animals and provide details on software tools available for convenient design of CRISPR/Cas9 targeting plasmids. We also discuss the future prospects of this advanced molecular technology.

Larvicidal and Pupicidal Activities of Alizarin Isolated from Roots of Rubia cordifolia Against Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae)

The mosquitocidal activities of different fractions and a compound alizarin from the methanol extract of Rubia cordifolia roots were evaluated on larvae and pupae of Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae). Larvae and pupae were exposed to concentrations of 2.5, 5.0, 7.5 and 10 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the mortality was assessed and the LC50 and LC90 values were estimated for larvae and pupae. Among the 23 fractions screened, fraction 2 from the methanol extract of R. cordifolia showed good mosquitocidal activity against C. quinquefasciatus and A. aegypti. LC50 and LC90 values of fraction 2 were 3.53 and 7.26 ppm for C. quinquefasciatus and 3.86 and 8.28 ppm for A. aegypti larvae, and 3.76 and 7.50 ppm for C. quinquefasciatus and 3.92 and 8.05 ppm for A. aegypti pupae, respectively. Further, the isolated compound alizarin presented good larvicidal and pupicidal activities. LC50 and LC90 values of alizarin for larvae were 0.81 and 3.86 ppm against C. quinquefasciatus and 1.31 and 6.04 ppm for A. aegypti larvae, respectively. Similarly, the LC50 and LC90 values of alizarin for pupae were 1.97 and 4.79 ppm for C. quinquefasciatus and 2.05 and 5.59 ppm for A. aegypti pupae, respectively. The structure of the isolated compound was identified on the basis of spectroscopic analysis and compared with reported spectral data. The results indicated that alizarin could be used as a potential larvicide and pupicide.

Quantitative ethnomedicinal survey of medicinal plants given for cardiometabolic diseases by the non-institutionally trained siddha practitioners of Tiruvallur district, Tamil Nadu, India

ETHNOBOTANICAL RELEVANCE

The burden of cardiometabolic diseases such as dyslipidemia, hyperglycemia, hypertension, visceral obesity and atherosclerotic cardiovascular diseases and the use of traditional medicine for the management of such diseases are high in India; hence there is a need to document and analyze such therapies.

AIM OF THE STUDY

This study documented and analyzed the medicinal plants prescribed for cardiometabolic diseases by the non-institutionally trained siddha practitioners of Tiruvallur district of Tamil Nadu, India.

METHODOLOGY

The field survey was conducted between December 2014 to November 2015. Successive free listing assisted with field-walks was used to interview the informants. After assessing the sampling sufficiency using rarefaction curve analysis, indices such as Informant Consensus Factor (Fic) and Index of Agreement on Remedies (IAR) were calculated for the data. The indicators of informant's medicinal plant knowledge such as Shannon's index, equitability index, etc., were regressed with the demographic profile of the informants.

RESULTS

For this study 70 non-institutionally trained Siddha medical practitioners were approached; the data from 36 practitioners who were treating cardiometabolic diseases were documented. This study recorded the use of 188 species which were used to prepare 368 formulations to treat illnesses categorized under cardiometabolic diseases. In this, 53.04% claims were singletons. Regression analysis showed that single species dominance was reduced and the diversity of medicinal plants was increased with the increase in the age and experience. Increase in the years of formal education increased the equitability in the uses. The plants such as Nelumbo nucifera Gaertn. (cardiovascular diseases), Allium sativum L. (dyslipidemia), Cuminum cyminum L. (hypertension), Macrotyloma uniflorum Verdc. (obesity) and Azadirachta indica A. Juss. (type 2 diabetes) were the highly cited medicinal plants.

CONCLUSION

This survey has identified the plants most commonly used by Siddha practitioners of Tiruvallur district, Tamil Nadu, India for cardiometabolic diseases. The prevalence of chronic, non-communicable metabolic illnesses such as type 2 diabetes, hypertension and obesity are increasing worldwide due to the rapid changes in the lifestyle. These ailments require a life-long care and in such instances, people tend to use complementary therapies in most cases, alongside with conventional therapies. In view of the high use of traditional therapies for treating cardiometabolic illnesses, this study supports the need for more research to evaluate the potential benefits of the treatments and to identify any safety concern.

In vitro antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone induced apoptosis against COLO320 cells through cytochrome c release caspase mediated pathway with PI3K/AKT and COX-2 inhibition

The present study investigated the anticancer activity of 2,3-dihydroxy-9,10-anthraquinone against different cancer cells such as MCF-7, COLO320, HepG-2, Skov-3, MOLM-14, NB-4, CEM, K562, Jurkat, HL-60, U937, IM-9 and Vero. 2,3-dihydroxy-9,10-anthraquinone showed good antiproliferative activity against COLO320 cells when compared to other tested cells. The cytotoxicity results showed 79.8% activity at the dose of 2.07 μM with IC50 value of 0.13 μM at 24 h in COLO320 cells. So we chose COLO320 cells for further anticancer studies. mRNA expression was confirmed by qPCR analysis using SYBR green method. Treatment with 2,3-dihydroxy-9,10-anthraquinone was found to trigger intrinsic apoptotic pathway as indicated by down regulation of Bcl-2, Bcl-xl; up regulation of Bim, Bax, Bad; release of cytochrome c and pro-caspases cleaving to caspases. Furthermore, 2,3-dihydroxy-9,10-anthraquinone stopped at G0/G1 phase with modulation in protein levels of cyclins. On the other hand PI3K/AKT signaling plays an important role in cell metabolism. We found that 2,3-dihydroxy-9,10-anthraquinone inhibits PI3K/AKT activity after treatment. Also, COX-2 enzyme plays a major role in colorectal cancer. Our results showed that the treatment significantly reduced COX-2 enzyme in COLO320 cells. These results indicated antiproliferative activity of 2,3-dihydroxy-9,10-anthraquinone involving apoptotic pathways, mitochondrial functions, cell cycle checkpoint and controlling the over expression genes during the colorectal cancer. Molecular docking studies showed that the compound bound stably to the active sites of Bcl-2, COX-2, PI3K and AKT. This is the first report of anticancer mechanism involving 2,3-dihydroxy-9,10-anthraquinone in COLO320 cells. The present results might provide helpful suggestions for the design of antitumor drugs toward colorectal cancer treatment.

Assessment of genetic diversity, population structure and relationships in Indian and non-Indian genotypes of finger millet (Eleusine coracana (L.) Gaertn) using genomic SSR markers

We evaluated the genetic variation and population structure in Indian and non-Indian genotypes of finger millet using 87 genomic SSR primers. The 128 finger millet genotypes were collected and genomic DNA was isolated. Eighty-seven genomic SSR primers with 60–70 % GC contents were used for PCR analysis of 128 finger millet genotypes. The PCR products were separated and visualized on a 6 % polyacrylamide gel followed by silver staining. The data were used to estimate major allele frequency using Power Marker v3.0. Dendrograms were constructed based on the Jaccard’s similarity coefficient. Statistical fitness and population structure analyses were performed to find the genetic diversity. The mean major allele frequency was 0.92; the means of polymorphic alleles were 2.13 per primer and 1.45 per genotype; the average polymorphism was 59.94 % per primer and average PIC value was 0.44 per primer. Indian genotypes produced an additional 0.21 allele than non-Indian genotypes. Gene diversity was in the range from 0.02 to 0.35. The average heterozygosity was 0.11, close to 100 % homozygosity. The highest inbreeding coefficient was observed with SSR marker UGEP67. The Jaccard’s similarity coefficient value ranged from 0.011 to 0.836. The highest similarity value was 0.836 between genotypes DPI009-04 and GPU-45. Indian genotypes were placed in Eleusine coracana major cluster (EcMC) 1 along with 6 non-Indian genotypes. AMOVA showed that molecular variance in genotypes from various geographical regions was 4 %; among populations it was 3 % and within populations it was 93 %. PCA scatter plot analysis showed that GPU-28, GPU-45 and DPI009-04 were closely dispersed in first component axis. In structural analysis, the genotypes were divided into three subpopulations (SP1, SP2 and SP3). All the three subpopulations had an admixture of alleles and no pure line was observed. These analyses confirmed that all the genotypes were genetically diverse and had been grouped based on their geographic regions.

New antimicrobial anthraquinone 6,61-bis (1,5,7-trihydroxy-3-hydroxymethylanthraquinone) isolated from Streptomyces sp. isolate ERI-26

The present report is about Streptomyces sp. isolate ERI-26 isolated from the soil sample of Nilgiri forest, Western Ghats. The methanol extract of ERI-26 showed good antimicrobial activity against tested microbes. The antimicrobial novel anthraquinones were purified by bioactivity-guided fractionation using a silica gel column and preparative HPLC. The compound was characterized and identified by UV, IR, NMR and MASS spectral data. The compound named as 6,6¹-bis (1,5,7-trihydroxy-3-hydroxymethylanthraquinone), showed significant antimicrobial activities against tested microbes. The isolated compound inhibited the tested bacterial growth, Staphylococcus aureus at 62.5 μg/ml, Staphylococcus epidermidis at 15.62 μg/m, Bacillus subtilis at 62.5 μg/ml, fungi; Trichophyton mentagrophytes at 15.62 μg/m Trichophyton simii at 15.62 μg/ml, Aspergillus niger at. 7.81 μg/ml, Aspergiller flavus at 3.90 μg/ml, Trichophyton rubrum 296 at 62.5 μg/ml, T. rubrum 57/01 at 7.81 μg/ml, Magnaporthe grisea at 15.62 μg/ml. and Botrytis cinerea at 3.90 μg/ml. Isolated anthraquinone compound and its antimicrobial activity were newly reported.

Delivery of chitosan/dsRNA nanoparticles for silencing of wing development vestigial (vg) gene in Aedes aegypti mosquitoes

RNA interference (RNAi) has been used as a gene silencing strategy by the introduction of long double stranded RNA (dsRNA) for the control of pest insects. The aim of the present study was to examine whether the expression of vg gene which is responsible for wing development, can be repressed by chitosan/dsRNA based nanoparticles in Aedes aegypti. The vestigial gene (vg) was amplified from adult mosquito and cloned in pLitmus28i vector. Genetically engineered recombinant plasmid was transformed into RNase III deficient strain for synthesis of bacterially expressed dsRNA. Nanoparticles were prepared via electrostatic interaction between cationic polymer chitosan and anionic nucleic acids (dsRNA). The formation of chitosan/dsRNAnanoparticles and their size were confirmed by Atomic force microscopy (AFM). Chitosan/dsRNA mediated knockdown of Enhanced Green Fluorescence Protein (EGFP) was demonstrated in Sf21 cells. Further, we tested whether such an approach could be used to target vg gene in Ae. aegypti. The results showed that chitosan/dsRNA caused significant mortality, delayed growth development and caused adult wing-malformation. A qRT-PCR analysis confirmed that the chitosan/dsRNA mediated transcriptional level was downregulated. Our findings suggest that vg gene intervention strategies through RNAi can emerge as viable option for pest control.

Effect of active sub-fraction of Ichnocarpus frutescens (L.) R.Br. in the management of obesity

AIM OF THE STUDY

Ichnocarpus frutescens (L.) R.Br. (Apocynaceae) is used by the traditional healers in India to treat diabetes and hyperlipidemia.This work aims to study the antiobesity effect of the active sub-fraction obtained from the leaves of this plant using in vitro and in vivo models.

METHODOLOGY

Active sub-fraction (Sfr3) isolated by column chromatography was analyzed using Gas chromatography and mass spectrometry. Adipogenesis and apoptosis were detected by oil red O and Hoechst-33342 staining, respectively, in 3T3-L1 adipocytes. Expression of specific marker genes involved in lipid metabolism was detected by Reverse Transcriptase Polymerase Chain Reaction in 3T3-L1 adipocytes and adipose tissues of C57 BL/6J mice, fed with high fat diet (HFD) and treated with Sfr3 and fenofibrate for 45 days.

RESULTS

The treatment with Sfr3 decreased lipid accumulation and caused apoptosis in adipocytes. In the HFD induced obese animals, serum and liver lipid levels were decreased and a significant decrease in body weight gain was observed dose dependently in 45 days treatment. Histopathological examination showed decrease in adipose mass and liver lipid accumulation. The effect of Sfr3 on the marker genes of adipocytes was significantly regulated at the treated doses both in vitro and in vivo.

CONCLUSION

Sfr3 of Ichnocarpus frutescens is effective in the management of obesity through adipocyte apoptosis.

In vitro anticancer activity of methyl caffeate isolated from Solanum torvum Swartz. fruit

The present study was undertaken to investigate the anticancer activity of methyl caffeate isolated from Solanum torvum Swartz. fruit and to explore the molecular mechanisms of action in MCF-7 cells. Cytotoxic properties of hexane, ethyl acetate and methanol extracts were carried out against MCF-7 cells using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide assay. Ethyl acetate extract showed good cytototoxic activities compared to hexane and methanol extracts. Methyl caffeate was isolated from the ethyl acetate extract using column chromatography. Cytotoxic properties of methyl caffeate was investigated against MCF-7, A549, COLO320, HepG-2 and Vero cells. The compound showed potent cytotoxic properties against MCF-7 cells compared to A549, COLO320 and HepG-2 cells. Methyl caffeate significantly reduced cell proliferation and increased formation of fragmented DNA and apoptotic body in MCF-7 cells. Bcl-2, Bax, Bid, p53, caspase-3, PARP and cytochrome c release were detected by western blot analysis. The activities of caspases-3 and PARP gradually increased after the addition of isolated compound. Bcl-2 protein was down regulated; Bid and Bax were up regulated after the treatment with methyl caffeate. Molecular docking studies showed that the compound bound stably to the active sites of poly (ADP-ribose) polymerase-1 (PARP1), B cell CLL/lymphoma-2 (BCL-2), E3 ubiquitin-protein ligase (MDM2) and tubulin. The results strongly suggested that methyl caffeate induced apoptosis in MCF-7 cells via caspase activation through cytochrome c release from mitochondria.

Characterization and phylogenetic analysis of novel polyene type antimicrobial metabolite producing actinomycetes from marine sediments: Bay of Bengal, India

OBJECTIVE

To isolate and indentify the promising antimicrobial metabolite producing Streptomyces strains from marine sediment samples from Andrapradesh coast of India.

METHODS

Antagonistic actinomycetes were isolated by starch casein agar medium and modified nutrient agar medium with 1% glucose used as a base for primary screening. Significant antimicrobial metabolite producing strains were selected and identified by using biochemical and 16S rDNA level. Minimum inhibitory concentrations of the organic extracts were done by using broth micro dilution method.

RESULTS

Among the 210 actinomycetes, 64.3% exhibited activity against Gram positive bacteria, 48.5 % showed activity towards Gram negative bacteria, 38.8% exhibited both Gram positive and negative bacteria and 80.85 % isolates revealed significant antifungal activity. However, five isolates AP-5, AP-18, AP-41 and AP-70 showed significant antimicrobial activity. The analysis of cell wall hydrolysates showed the presence of LL-diaminopimelic acid and glycine in all the isolates. Sequencing analysis indicated that the isolates shared 98.5%-99.8% sequence identity to the 16S rDNA gene sequences of the Streptomyces taxons. The antimicrobial substances were extracted using hexane and ethyl acetate from spent medium in which strains were cultivated at 30°Cfor five days. The antimicrobial activity was assessed using broth micro dilution technique. Each of the culture extracts from these five strains showed a typical polyene-like property. The lowest minimum inhibitory concentrations of ethyl acetate extracts against Escherichia coli and Curvularia lunata were 67.5 and 125.0 µg/mL, respectively.

CONCLUSIONS

It can be concluded that hexane and ethyl acetate soluble extracellular products of novel isolates are effective against pathogenic bacteria and fungi.

Toxic Effects of Couroupita guianensis Against Spodoptera litura (Fabricius) (Lepidoptera: Noctuidae)

Laboratory experiments were conducted to find out the efficacy of different crude extracts and fractions of Couroupita guianensis (Lecythidaceae) against Spodoptera litura (Fabricius). Results revealed that hexane, chloroform and ethyl acetate extracts of C. guianensis showed larvicidal and pupicidal activities against S. litura. Maximum larvicidal activity (68.66%) was observed in hexane extract at 5.0% concentration followed by chloroform and ethyl acetate extracts, and least LC50 value of 2.64% was observed in hexane extract. A 100% pupicidal activity was observed in hexane extract. Based on the efficacy of crude extracts, the effective crude extract (hexane extract) was further fractionated and subjected to screening for biological activities against S. litura. Among the eight fractions isolated from the hexane extract, fraction 8 showed maximum antifeedant activity (81. 8%) and larvicidal activity (76.9%) at 1000-ppm concentration; this fraction showed least LC50 value of 375.92 ppm for larvicidal activity. Cent per cent pupicidal activity was recorded. Reduced midgut and hemolymph protein contents were observed at 1000 ppm of fraction 8. Histopathological studies revealed that fraction 8 severely damaged the midgut cells of S. litura. This fraction could be used to develop botanical formulation to control agricultural pests.

Bioassay guided fractionation and identification of active anti-inflammatory constituent from Delonix elata flowers using RAW 264.7 cells

CONTEXT

Delonix elata (L.) Gamble (Fabaceae) has been used in the Indian traditional medicine system to treat rheumatism and inflammation.

AIM

To assess the anti-inflammatory effect of Delonix elata flowers and to isolate the active principle.

MATERIALS AND METHODS

The prompt anti-inflammatory constituent was isolated from Delonix elata flower extracts using bioassay guided fractionation in liposaccharide (LPS) stimulated RAW 264.7 macrophage cell line. The anti-inflammatory activity of extracts/fractions/sub-fractions/compounds (10, 25, and 50 µg/ml) was evaluated by estimating the levels of nitric oxide (NO), TNF-α, and IL-1β after 24 h of LPS induction (1 μg/ml). The isolated active compound was subjected to NMR, IR, and UV analyses for structure determination.

RESULTS

In an attempt to search for anti-inflammatory constituents, the active pure principle was isolated and crystallized as a white compound from Delonix elata flowers methanol extract. This active compound (50 µg/ml) decreased the release of inflammatory mediators levels such as NO (0.263 ± 0.03 µM), TNFα (160.20 ± 17.57 pg/ml), and IL-1β (285.79 ± 15.16 pg/ml) significantly (p < 0.05); when compared to the levels of NO (0.774 ± 0.08 µM), TNFα (501.71 ± 25.14 pg/ml), and IL-1β (712.68 ± 52.25 pg/ml) from LPS-stimulated macrophage cells. The active compound was confirmed as hesperidin with NMR, IR, and UV spectroscopy data. This is the first report of this compound from Delonix elata flowers.

CONCLUSION

The findings of the study support the traditional use of Delonix elata flowers to treat inflammation.

A flavonoid isolated from Streptomyces sp. (ERINLG-4) induces apoptosis in human lung cancer A549 cells through p53 and cytochrome c release caspase dependant pathway

The aim of this study was to investigate the anticancer activity of a flavonoid type of compound isolated from soil derived filamentous bacterium Streptomyces sp. (ERINLG-4) and to explore the molecular mechanisms of action. Cytotoxic properties of ethyl acetate extract was carried out against A549 lung cancer cell line using the 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT) assay. Cytotoxic properties of isolated compound were investigated in A549 lung cancer cell line, COLO320DM cancer cell line and Vero cells. The compound showed potent cytotoxic properties against A549 lung cancer cell line and moderate cytotoxic properties against COLO320DM cancer cell line. Isolated compound showed no toxicity up to 2000 μg/mL in Vero cells. So we have chosen the A549 lung cancer cell line for further anticancer studies. Intracellular visualization was done by using a laser scanning confocal microscope. Apoptosis was measured using DNA fragmentation technique. Treatment of the A549 cancer cells with isolated compound significantly reduced cell proliferation, increased formation of fragmented DNA and apoptotic body. Activation of caspase-9 and caspase-3 indicated that compound may be inducing intrinsic and extrinsic apoptosis pathways. Bcl-2, p53, pro-caspases, caspase-3, caspase-9 and cytochrome c release were detected by western blotting analysis after compound treatment (123 and 164 μM). The activities of pro-caspases-3, caspase-9 cleaved to caspase-3 and caspase-9 gradually increased after the addition of isolated compound. But Bcl-2 protein was down regulated after treatment with isolated compound. Molecular docking studies showed that the compound bound stably to the active sites of caspase-3 and caspase-9. These results strongly suggest that the isolated compound induces apoptosis in A549 cancer cells via caspase activation through cytochrome c release from mitochondria. The present results might provide helpful suggestions for the design of antitumor drugs toward lung cancer treatment.

Novel 1,5,7-trihydroxy-3-hydroxy methyl anthraquinone isolated from terrestrial Streptomyces sp. (eri-26) with antimicrobial and molecular docking studies

Streptomyces sp. isolate ERI-26 was obtained from the Nilgiris forest soil of Western Ghats, Tamil Nadu, India. Novel anthraquinone compound was isolated from the active fraction 5; it was identified by spectroscopical data using UV, IR, NMR and MASS. The isolated compound 1,5,7-trihydroxy-3-hydroxy methyl anthraquinone was tested against bacteria and fungi at minimum inhibitory concentration level. The compound showed significant antimicrobial activity against bacteria, Staphylococcus aureus at 125 μg/ml, Staphylococcus epidermidis at 62.5 μg/m, Bacillus subtilis at 31.25 μg/ml, fungi; Epidermophyton floccosum at 62.5 μg/ml, Aspergillus niger at 31.25 μg/ml, Aspergiller flavus at 31.25 μg/ml, Trichophyton rubrum at 62.5 μg/ml and Botrytis cinerea at 62.5 μg/ml. The isolated compound was subjected to molecular docking studies for the inhibition of TtgR, topoisomerase IV and AmpC β-lactamase enzymes which are targets for antimicrobials. Docking studies of the compound showed low docking energy indicating its usefulness as antimicrobial agent. 1,5,7-Trihydroxy-3-hydroxy methyl anthraquinone is new, and its antimicrobial and molecular docking properties are reported for the first time.

Isolation, screening and partial purification of antimicrobial antibiotics from soil Streptomyces sp. SCA 7

Thirty-seven actinomycetes strains were isolated from soil samples collected from an agriculture field in Vengodu, Thiruvannamalai District, Tamil Nadu, India (latitude: 12° 54' 0033″, North; longitude: 79° 78' 5216″, East; elevation: 228.6/70.0 ft/m). The isolates were assessed for antagonistic activity against five Gram-positive bacteria, seven Gram-negative bacteria, and two pathogenic fungi. During the initial screening, 43% of the strains showed weak activity, 16% showed moderate activity, 5% showed good activity, and 35% showed no antagonistic activity. Among the strains tested, SCA 7 showed strong antimicrobial activity. Maximum biological activity was obtained on modified nutrient glucose agar (MNGA) medium. The mycelia of SCA 7 were extracted with methanol and tested against microbial pathogens using the disc diffusion method. The crude extract was purified partially using column chromatography and assessed for antimicrobial activity. Fraction 10 showed good activity against Staphylococcus epidermidis (31.25 μg/mL) and Malassezia pachydermatis (500 μg/mL) and the active principle (fraction 10) was identified as 2,4-bis (1,1-dimethylethyl) phenol. Based on morphological, physiological, biochemical, cultural, and molecular characteristics (16S rDNA sequencing), this strain was identified as Streptomyces sp. SCA 7. It could be used in the development of new substances for pharmaceutical or agricultural purposes.

Synthesis of new class of spirocarbocycle derivatives by multicomponent domino reaction and their evaluation for antimicrobial, anticancer activity and molecular docking studies

A series of 25 new spirocarbocycles were synthesized by a three component reaction that involves few cyclic nucleophiles, vinyl malononitriles and aldehydes with variable substitution patterns. All the synthesized compounds were evaluated for their antimicrobial activity and the compounds showed significant activity. Synthesized compounds 4c, 4i and 6i showed good anticancer activity against A549 cancer cell line. Molecular docking studies indicated that compound 4i had the greatest affinity for DNA gyrase receptor than others and compound 6i had the greatest affinity for anaplastic lymphoma kinase (ALK) receptor. These compounds can be better therapeutic agents for microbial and cancer cell lines.

Myroides pelagicus from the gut of Drosophila melanogaster attenuates inflammation on dextran sodium sulfate-induced colitis

BACKGROUND AND AIM

Probiotics are live microorganisms that confer a health benefit on the host when administered in adequate amounts. In the present study, the putative probiotic strain was identified from the gut of Drosophila melanogaster and assessed for its protective effect in inflammatory bowel disease.

METHODS

Active probiotics were screened from the Drosophila melanogaster gut by the selection criteria of gastric juice tolerance, hydrophobic property, antimicrobial potential, adhesion, and invasion properties. The active probiotics were identified by 16s rDNA sequencing and the effect of these active probiotics was evaluated in a Dextran sulphate sodium (DSS)-induced mice model by estimating inflammatory markers and histopathological changes.

RESULTS

Nine Gram-positive and bile salt tolerant bacterial isolates were obtained from the gut samples. The isolates PTH 2, PTH 4, and PTH 7 clearly showed significant activity in antimicrobial potential, hydrophobic (>74%) property, and intestinal juice tolerance. Among these, PTH 7 was selected for further studies due to its significant low-invasion ability and it proved capable of reducing the secretion of proinflammatory cytokines. The 16s rDNA studies revealed that PTH 7 was Myroides pelagicus. Administration of M. pelagicus to the DSS-induced colitic animals significantly suppressed myeloperoxidase, ALP, and malondialdehyde levels, and also lowered levels of proinflammatory cytokine expression. Further, the recovery from the disease by the probiotic treatment was supported by histopathological and macroscopic observation. The treated animals did not show any adverse signs in their physiology or behavior.

CONCLUSION

Myroides pelagicus successfully prohibited inflammatory markers and acted as a potent probiotic. Future studies with this stain might prove its efficacy as a drug for the management of colitis.