A cross talk based critical analysis of solvent free microwave extraction to accentuate it as the new normal for extraction of essential oil: an attempt to overhaul the science of distillation through a comprehensive tutelage.

Microwave-assisted extraction (MAE) is a sustainable non-contact heating source and has been extensively researched for extraction of plant bioactives. There are various derivatives or modules available for MAE and solvent free microwave extraction (SFME) is one of them where by operational aspects of MAE have been maneuvered to make it compatible for extraction of essential oil (EO). This article makes an attempt to overhaul the science of distillation by revisiting SFME and trying to learn through a comprehensive tutelage comprising of 20 years of published literature in Web of Science so that a shrewd decision can be obtained through a cross talk based critical analysis on the science SFME. A total of 312 articles within the time frame of 2001-2020 were extracted from WOS and critically analyzed. Considering the various uncertainties involved with SFME the articles establishes some global working standards and tries to explore the dynamic relationship between plant part/genus and microwave power, microwave power and time, microwave power and extracted volatile principles, prioritizes plant family selection and also presents a research blueprint of SFME. A techno-commercial feasibility study has been presented for smooth industrial transition of SFME. The tutelage presented decodes the publication trends and SFME blueprint.

Assessment of mycorrhizal association of a threatened medicinal plant Clerodendrum indicum (L.) O. Kuntze (Verbenaceae) in different ecological variations.

Mycorrhizae association is reported to enhance the survivability of the host plant under adverse environmental conditions. The present study aims to explore the mycorrhizal association in the roots of different ecotypes of a threatened medicinal plant, Clerodendrum indicum (L.) O. Kuntze (Verbenaceae), collected from W.B., India, which correlates the degree of root colonization to the nutritional status of the native soil. Ten ecotypes of C. indicum having diverse morphological variations were collected. The mycorrhizae were characterized by both morphological and molecular methods. The nutritional status of the native soils was estimated. The study revealed that all the ecotypes have an association with mycorrhizal forms like hyphae, arbuscules, and vesicles. The molecular analysis showed Glomus intraradices and Rhizophagus irregularis as the associated arbuscular mycorrhizal fungi (AMF). A significant variation in arbuscule and vesicle formation was found growing in the varied nutritional statuses concerning soil parameters. The arbuscule was found negatively correlated with pH, conductivity, and potassium and positively correlated with organic carbon, nitrogen, and phosphorus. The vesicle was found positively correlated with pH, organic carbon, and potassium and negatively correlated with conductivity, nitrogen, and phosphorus. The interaction between conductivity: nitrogen, conductivity: phosphorus, organic-carbon: nitrogen, and pH: conductivity was significant in influencing vesicle formation. However, none of the interactions between parameters was found significant in influencing arbuscule formation. Thus, the study concludes that G. intraradices and R. irregularis are the principle mycorrhizae forming the symbiotic association with the threatened medicinal plant, C. indicum. They form vesicles and arbuscules based on their soil nutritive factors. Therefore, a large-scale propagation through a selective AMF association would help in the conservation of this threatened species from extinction.

Anti-enteric efficacy and mode of action of tridecanoic acid methyl ester isolated from Monochoria hastata (L.) Solms leaf.

Monochoria hastata (L.) Solms (family Pontederiaceae), an ethnomedicinal aquatic herb, is used to remedy several gastrointestinal diseases by various ethnic groups in India. The present study aimed to purify and characterize the antibacterial active ingredient against gastrointestinal (GI) diseases and its mode of action using in vitro experimental models. The active lead molecule in the ethyl acetate extract (EA-Mh) fraction has been purified and characterized through high-performance liquid chromatography (HPLC), proton nuclear magnetic resonance (1H NMR), and electrospray ionization mass spectrometry (ESI-MS) methods. The anti-enteric efficacy has been evaluated against enteropathogenic Gram-positive and Gram-negative bacteria by minimum inhibitory concentration (MIC), minimum bactericidal concentration (MBC), lactate dehydrogenase (LDH), and scanning electron microscopy (SEM) studies. The synergistic and antagonistic studies were done on E. coli MTCC 723 using standard antibiotics (ampicillin and kanamycin, final conc. 50 µg/ml) in a sterilized 96-well micro-plate, incubated at 37 ℃ for 24 h. The chromatographic and spectroscopic analyses revealed the presence of tridecanoic acid methyl ester (TAME) in the bioactive fraction. The compound causes significant extracellular leakage activity by disrupting cellular morphology in the Enterococcus faecalis MCC 2041 T and Salmonella enterica serovar Typhimurium MTCC 98, at a dose of 375 µg/ml and 750 µg/ml, respectively. The SEM study shows a significant rupturing of E. coli and E. faecalis cells due to TAME induced autolysis. It has synergistic activity with ampicillin. The in silico molecular docking through the AutoDock Vina 4.2 and GROMACS (ver. 5.1) Charmm27 force field results showed that the TAME had a strong binding affinity Escherichia coli DNA Gyrase B (PDB ID: 5l3j.pdb) protein and caused conformational changes. Thus, the manuscript reports the first time on the characterization of TAME from this plant with a detailed antibacterial mode of action studies.

A status report with critical analysis of research trends in exploring medicinal plants as antiviral: Let us dig into the history to predict the future.

The review article serves as a mini directory of medicinal plants (662 medicinal plants have been identified) that have been investigated for antiviral property between 2015 and 2019. Data have been extracted from Scopus using specific keywords followed by manual sorting to avoid any duplication. Critical analyses of handpicked data have been presented. Mapping of medicinal plants, followed by critical analysis on the families and plant parts investigated in the said tenure, and its correlation with the participating countries and virus types have been critically analyzed. Interceptive role of phytochemicals in impeding viral replication has also been taken note of. Emphasis on India's exploration of various medicinal plants has also been given. Also presents a tutelage, which is likely to revive the interest in natural products for search of potential antivirals. This review is expected to serve as a rich data bank and as a guiding principle for researchers who are planning to explore medicinal plants in search for potential antiviral. It is time that researchers need to revisit their countries' own history of traditional medicine to predict something worthful in future.

In search of suitable extraction technique for large scale commercial production of bioactive fraction for the treatment of diabetes: The case Diospyros melanoxylon Roxb.

Diospyros melanoxylon Roxb. (D. melanoxylon) belongs to the family Ebenaceae and its leaves are very well known for making beedi throughout the World. The current study estimated the comparative extraction technique and its in-vitro antidiabetic prospective of the leaves of D. melanoxylon. Qualitative phytochemicals analysis of the samples from D. melanoxylon was carried out for the detection of secondary metabolites. Total phenolics, flavonoids, triterpenoids and tannins content of D. melanoxylon were estimated using colorimetric assay. Microwave-assisted extraction (MAE) technique with a low carbon output was observed for the speedy extraction of bioactive compounds obtained from Diospyros melanoxylon leaf extract. MAE produced a maximum yield of bioactive compounds which was found to be more efficient than ultrasound, soxhlet and maceration extraction. Qualitative HPLC analysis was performed for bioactive compounds. The in-vitro antidiabetic assay was performed using α-amylase and α-glucosidase inhibitory activity. In conclusion, the fractions exhibited the concentration-dependent inhibitory effect with significant (P < 0.0001) result. So the above performance might be accountable for the antidiabetic activity of D. Melanoxylon leaf extract due to presence of bioactive compounds.

Critical analysis and mapping of research trends and impact assessment of polyaromatic hydrocarbon accumulation in leaves: let history tell the future.

The article is basically an attempt to provide a consolidated report on impact assessment and trends in research pertaining to accumulation and curbing the menace of polyaromatic hydrocarbon (PAH) accumulation in leaves. Emphasis is given to understand the consequences of the fact that edible/medicinal plants cultivated in PAH contaminated soil or close to such places which are potential liberators of PAHs can virtually act as transporters for direct PAH entry into biological systems. An attempt has been made to predict the future by digging out golden facts from history. Extensive Scopus-based data mining has been done to dig out research data since last 10 years (2006-2016) pertaining to the said area. Critical analysis of statistical data on research trends highlighting the different aspects of evaluation of PAH accumulation in leaves has been described. The concentrate of all researches for the said period have been presented as few golden principles which shall serve as important facts for researchers and policy makers for curbing the menace of PAH-induced oxidative stress in plants and shall also provide start-up ideas for researchers new to the area. Critical analysis of trends in phytoremediation aspect has also been duly highlighted to measure the intensity of restoration steps taken by researchers and government to safeguard the future generations.

Physicochemical and elemental studies of Hydrocotyle javanica Thunb.for standardization as herbal drug

Objective:To explore the leaves of Hydrocotylejavanica Thunb.as a source of safe and effective antibacterial herbal medicine.Methods:The standardization was validated by stepwise physicochemical studies,element analysis,determination of ash values,fluorescence analysis,assessment of moisture content,extractive values in different solvent systems and extraction methods.Heavy metal contents,mineral and element contents were analysed by atomic absorption spectrophotometry,inductively coupled plasma-mass spectrometer and CHNS/O analyser,respectively.Results:The methanol extract of the folklore medicinal plant having antibacterial efficacy contained flavonoids and phenolic OH groups.The ICP multi standard indicated the presence of three major compounds with molecular mass of 161 190 and 221 Da.Heavy metals viz.lead,mercury and copper content were 4.38 ppm,＜ 0.05 ppm and 24.70 ppm,respectively.Minerals content of calcium,phosphorus,potassium and iron were 1 190.94 mg/100 g,375.57 mg/100 g,2820 mg/100 g and 340.20 mg/100 g of plant sample,respectively.Elements like carbon,hydrogen,nitrogen and sulphur contents were 38.18％,5.67％,2.23％ and 0.51％,respectively.Heavy metal profile of the tested plant was within the permissible limits of the regulatory authorities.Conclusions:Hence the present physicochemical and elements studies reveals that the plant Hydrocotylejavanica Thunb.could be a potent source of herbal preparation as well as a safe and novel synthetic antibacterial drug.

Assessment of traditional knowledge of the antidiabetic plants of Darjeeling and Sikkim Himalayas in the context of recent phytochemical and pharmacological advances.

Darjeeling and Sikkim Himalayas, a part of Eastern Himalayan Hotspot, is characterized by its richness of plant diversity. Herbal medicine has been one of the most popular and reliable healing practices among the different ethnic groups of this region for ages. However, the lack of documentation practice by the traditional healers has led to obscurity regarding the efficacy of herbal medicine among the present generation, though they have to depend on the same quite often. Meanwhile, several reviews have attempted to document the plants used for the treatment of diabetes from this region, but interestingly, very few research works can be obtained regarding the characterization of antidiabetic properties of the plants of this region. Therefore, it demands a better understanding of the potentiality of these plants in the purview of scientific evidence. This review article reports 55 such plant species which have been reported to be frequently used in the treatment of hyperglycemia and our objective was to validate the potentiality of the plants in the light of recent phytochemical and pharmacological researches being carried out locally or elsewhere.

Advances in herbal medicine for treatment of ischemic brain injury.

Ischemic brain injury is one of the leading causes of death worldwide and has attracted a lot of attention in the field of drug discovery. Cerebral ischemia is a complex pathological process involving a series of mechanisms, including generation of free radicals, oxidative stress, disruption of the membrane function, release of neurotransmitters and apoptosis. Thrombolytic therapy is the most effective therapeutic strategy, but the benefits are far from being absolute. Increased attention in the field of drug discovery has been focused on using natural compounds from traditional medicinal herbs for neuroprotection, which appears to be a promising therapeutic option for cerebral ischemia with minimal systemic adverse effects that could limit their long term use. The scenario calls for extensive investigations which can result in the development of lead molecules for neuroprotection in the future. In this context, the present review focuses on possible mechanisms underlying the beneficial effects of herbal drugs in patients with cerebral ischemic injury. Natural compounds have been demonstrated to have neurofunctional regulatory actions with antioxidative, anti-inflammatory, calcium antagonizing and anti-apoptotic activities. Among the several leads obtained from plant sources as potential neuroprotective agents, resveratrol, EGb761, curcumin and epigallocatechin-3-gallate have shown significant therapeutic benefits in cerebral ischemic conditions. However, ligustilide, tanshinone, scutellarin and shikonin are the few lead molecules which are under investigation for treatment of cerebral ischemia.

Modernization of Ayurveda: a brief overview of Indian initiatives.

Ayurveda has been the main guiding force in drug discovery from traditional medicine. In concept, this system is rooted in folk or ethnomedicine and in practice it shows further refinement and development in accordance with local traditions. Isolation of active principles from crude drugs, their pharmacological evaluation, therapeutic proving and clinical application resulted in the genesis of modem or so called allopathic medicine. To keep the opportunity alive for further development in traditional as well as modem medicines, it is necessary to have an uninterrupted connection with ethnomedicine. Since the practice of ethnomedicine is based on the age-long indigenous knowledge which has been orally transmitted through generations and sustained in traditions there is an urgent need to document such knowledge. The ongoing strategies adopted in India to document the precious traditional knowledge and conserve medicinal plants are discussed in this communication. India with her rich plant wealth and traditional knowledge about the medicinal use of plants has tremendous scope to provide leadership in ensuring human health and longevity.

A brief understanding of process optimisation in microwave-assisted extraction of botanical materials: options and opportunities with chemometric tools.

INTRODUCTION: Extraction forms the very basic step in research on natural products for drug discovery. A poorly optimised and planned extraction methodology can jeopardise the entire mission. OBJECTIVE: To provide a vivid picture of different chemometric tools and planning for process optimisation and method development in extraction of botanical material, with emphasis on microwave-assisted extraction (MAE) of botanical material. METHODS: A review of studies involving the application of chemometric tools in combination with MAE of botanical materials was undertaken in order to discover what the significant extraction factors were. Optimising a response by fine-tuning those factors, experimental design or statistical design of experiment (DoE), which is a core area of study in chemometrics, was then used for statistical analysis and interpretations. RESULTS: In this review a brief explanation of the different aspects and methodologies related to MAE of botanical materials that were subjected to experimental design, along with some general chemometric tools and the steps involved in the practice of MAE, are presented. A detailed study on various factors and responses involved in the optimisation is also presented. CONCLUSION: This article will assist in obtaining a better insight into the chemometric strategies of process optimisation and method development, which will in turn improve the decision-making process in selecting influential extraction parameters.

An inside to the better understanding of the ethnobotanical route to drug discovery--the need of the hour.

For pharmaceuticals ranging from Digitalis to vincristine, the ethnobotanical approach to drug discovery has proven successful. The value of ethnobotanical information in drug development is based on several factors, which are discussed. Published ethnomedical information has many strengths and weaknesses relative to the ability to establish a corresponding biological effect in the laboratory. The ability to correlate ethnomedical reports with corresponding scientific studies could lead to improved selection of plants for further scientific studies. The application of NAPRALERT database in this regard is also discussed. An elaborate plant to drug pathway has been traced out for young researchers to make the drug discovery pathway more approachable. Various cautions related to possible errors during the ethnobotanical approach have also been highlighted.

Recent advances in herbal medicine for treatment of liver diseases.

CONTEXT: Liver disease is a serious ailment and the scenario is worsened by the lack of precise therapeutic regimens. Currently available therapies for liver ailments are not apposite and systemic toxicity inhibits their long term use. Medicinal plants have been traditionally used for treating liver diseases since centuries as the toxicity factor appears to be on the lower side. OBJECTIVE: Several phytochemials have been identified which have significant hepatoprotective activity with minimal systemic adverse effects which could limit their long term use. The scenario calls for extensive investigations which can lead to development of lead molecules for hepatoprotective molecules of future. This review deals with the biological activity, mode of action and toxicity and forthcoming application of some of these leads. METHODS: These generally have strong antioxidative potential and cause induction of antioxidant enzymes like superoxide dismutase, reduced glutathione and catalase. Additional mechanisms of hepatoprotection include stimulation of heme oxygenase-1 activity, inhibition of nitric oxide production, hepatocyte apoptosis and nuclear factor-κB activation. RESULTS AND CONCLUSION: Out of the several leads obtained from plant sources as potential hepatoprotective agents, silymarin, andrographolide, neoandrographolide, curcumin, picroside, kutkoside, phyllanthin, hypophyllanthin, and glycyrrhizin have been established as potent hepatoprotective agents. The hepatoprotective potential of several herbal medicines has been clinically evaluated. Significant efficacy has been seen with silymarin, glycyrrhizin and Liv-52 in treatment of hepatitis, alcoholic liver disease and liver cirrhosis.

Effective Control of Type 2 Diabetes through Antioxidant Defense by Edible Fruits of Diospyros peregrina.

The matured fruits of Diospyros peregrina are successfully employed by the traditional healers and local people of costal West Bengal, India for the treatment of diabetes. Present investigation was undertaken to evaluate the role of hydroalcoholic extract of D. peregrina (HDP) on type 2 diabetes as well as the augmented oxidative stresses associated with it. Oral administration of HDP at 25, 50 and 100 mg kg(-1) body weight per day to diabetic rats was found to possess significant dose-dependent hypoglycemic and hypolipidemic activity. The diabetic rats showed lower activities of superoxide dismutase (SOD), catalase (CAT) and reduced glutathione (GSH) content in hepatic and renal tissues as compared to normal rats. The activities of SOD, CAT and GSH were found to be increased in extract-treated diabetic rats in selected tissues. The increased level of lipid peroxidation (thiobarbituric acid reactive substances) in diabetic rats was also found to be reverted back to near normal status in extract-treated groups. Thus it may be concluded that the HDP may produce its hypoglycemic effect through antioxidant defense mechanism.

Anti-inflammatory activity of a polyphenolic enriched extract of Schima wallichii bark.

In the present investigation, the anti-inflammatory activity of a polyphenolic enriched extract of Schima wallichii bark was evaluated in vitro using human peripheral blood mononuclear cells (PBMCs) and in vivo by carrageenan-induced paw oedema assay (acute study) and cotton pallet granuloma assay (chronic study). The extract exhibited significant inhibition of the production of tumour necrotic factor-α and interleukin-6 by PBMCs stimulated with lipopolysaccharide (LPS) in a concentration-dependent manner. The extract at the selected doses of 150 and 300 mg kg(-1) body weight p.o. exhibited significant dose-dependent anti-inflammatory responses, with 44.32 and 38.65% inhibition of inflammation in carrageenan-induced paw oedema and cotton pallet granuloma, respectively.

Role of modifier in microwave assisted extraction of oleanolic acid from Gymnema sylvestre: application of green extraction technology for botanicals.

This work highlights the development of a green extraction technology for botanicals with the use of microwave energy. Taking into consideration the extensive time involved in conventional extraction methods, coupled with usage of large volumes of organic solvent and energy resources, an ecofriendly green method that can overcome the above problems has been developed. The work compares the effect of sample pretreatment with untreated sample for improved yield of oleanolic acid from Gymnema sylvestre leaves. The pretreated sample with water produced 0.71% w/w oleanolic acid in one extraction cycle with 500 W microwave power, 25 mL methanol and only an 8 min extraction time. On the other hand, a conventional heat reflux extraction for 6 hours could produce only 0.62% w/w oleanolic acid. The detailed mechanism of extraction has been studied through scanning electron micrographs. The environmental impact of the proposed green method has also been evaluated.

Design and optimization of ultrasound assisted extraction of curcumin as an effective alternative for conventional solid liquid extraction of natural products.

The first step in the qualitative and quantitative analysis of medicinal plant constituents is the extraction step. Ideally, an extraction procedure should be exhaustive with respect to the constituents to be analyzed, rapid, simple, and for routine analysis amenable to automation. Usually, the traditional techniques require long extraction times, with more consumption of energy resources and organic solvent, have low efficiency and are often unsafe for thermolabile botanicals. The Taguchi based optimization technique was adapted for the process optimization of ultrasound assisted extraction (UAE) of Curcuma longa to identify the effect of four major factors namely, extraction time, solvent viscosity, grinding degree and solvent volume on the percentage extraction of curcumin. The reproducibility and recovery of the method was also investigated. The efficiency of the new extraction method was then compared with conventional solid liquid extraction procedures. Using this novel method, long hours of conventional Soxhlet extraction were cut down to 70 minutes of UAE with greater reproducibility and recovery. The study clearly shows that this method can be effectively utilized for cutting down long extraction time of botanicals to just a few minutes without the aid of heat.