Water Extract Of Bark Research Articles

Antioxidant Activities and Protective Effects of Shorea macrophylla Leaf and Bark Extracts

Shorea macrophylla, also known as the ‘Engkabang’ tree or Light Red Meranti, is renowned for its role in reforestation efforts. Despite lacking records of traditional use, the reported biological activities of other species within the Shorea genus spark curiosity about the potential biological activities of this plant. Therefore, this study aims to explore the antioxidant capabilities of S. macrophylla leaf and bark extracts, along with their protective effects against oxidative stress using a brine shrimp model. In the evaluation of antioxidant potential, 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays were employed. Extracts were incubated in DPPH and FRAP solutions, and absorbances were measured at 517 and 593 nm, respectively. The brine shrimp lethality assay (BSLT) involved exposing brine shrimps (Artemia salina) to various concentrations of the extract, with LC50 values determined through probit regression analysis. Oxidative stress protection assays entailed treating brine shrimps with safe doses of S. macrophylla extracts before exposure to H2O2, with subsequent observation of survival rates. The DPPH assay unveiled IC50 values of 1.025 and 0.693 mg/mL for S. macrophylla leaf and bark extracts, respectively, while FRAP values exhibited a concentration-dependent relationship. BSLT demonstrated concentration-dependent mortality, with LC50 values of 0.93 and 0.6455 mg/mL for S. macrophylla leaf and bark extracts, respectively. Pre-treatment with S. macrophylla extracts significantly increased brine shrimp survival against H2O2-induced oxidative stress. In conclusion, both S. macrophylla leaf and bark water extracts demonstrated noteworthy antioxidant activities and exhibited protective effects against oxidative stress in brine shrimps. These findings provide insights into the antioxidant activities and protective effects of S. macrophylla Leaf and Bark extracts.

Dietary supplementation of water extract of Eucommia ulmoides bark improved caecal microbiota and parameters of health in white-feathered broilers.

Eucommia ulmoides has been used as a food and medicine homologue for a long time in China. We hypothesize that Eucommia ulmoidesachieves its health-promoting effects via altering gut microbiota. Here, we investigated the effects of water extract of Eucommia ulmoides bark on caecal microbiota and growth performance, antioxidant activity, and immunity in white-feathered broilers treated for 42 days. A total of 108 one-day-old Cobb white-feathered broilers were randomly assigned to three treatment groups: control diet, 0.75% Eucommia ulmoides diet (EU Ⅰ) and 1.5% Eucommia ulmoides diet (EU Ⅱ). The results showed that EU Ⅱ treatment improved average body weight (ABW), thigh muscle quality and total length of intestines, and decreased the serum total triglycerides and total cholesterol (TC) (p < 0.05). Eucommia ulmoides supplementation increased serum superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), total antioxidant activities and content of immunoglobulins, and reduced levels of malondialdehyde and tumour necrosis factor-α (TNF-α) (p < 0.05). Moreover, the supplementation increased the diversity of caecal microbiota and reduced the pathogenic genera Escherichia Shigella and Helicobacter. The genera Ochrobactrum, Odoribater, Klebsiella, Enterobacter, Georgenia and Bifidobacterium were positively associated with the ABW, total intestinal length, serum levels of GSH-Px, SOD and immunoglobulins (p < 0.001) and negatively associated with the TC and TNF-α (p < 0.01), suggesting an association of the changes of gut microbiota and improvement of broiler health. Meanwhile, Eucommia ulmoides supplementation enriched the Kyoto Encyclopedia of Genes and Genomes pathway of exocrine secretion from the pancreas, circadian entrainmentand inhibited lipopolysaccharide biosynthesis. In conclusion, Eucommia ulmoides water extract can be used as a feed additive to improve poultry industry production.

Antioxidant, phytochemical and fatty acid profile of extracts from bark of Pterocarpus erinaceus

Pterocarpus erinaceus is reported locally to replenish the body nutrient, support the production of red blood cells and possesses anti-inflammatory activity. Standard methods were used to investigate the chemical constituents of the field and market bark samples of P. erinaceus. Field sample of P. erinaceus had significantly higher protein, (14.15%; 13.90%), than the market sample. The bark extracts had iron (4.04mg/100g-5.19mg/100g) and other minerals. Phytochemicals in P. erinaceus bark extracts include; flavonoid, saponin, phytate and tannin. The highest antioxidant activity was obtained from field bark water extract (FBW) with an IC50­­ of 12.53µg/ml. Fatty acid profile of P. erinaceus bark revealed that it contains linoleic acid (72.35%), palmitic acid (18.73%), D-limonene (44.93%) and D-carvone (11.99%). This study gathered that bark extracts of P. erinaceus contain essential nutrients and fatty acid which may support growth in the body and may be employed in the production of functional food.

Cardioprotective effects of Musanga cecropioides Welw. Ex Benth extracts on isoproterenol-induced acute myocardial infarction in Wistar rats.

Background of the study: Acute myocardial infarction (AMI) is a prominent etiology of heart failure-related death worldwide. Musanga cecropioides Welw. Ex Benth bark water extract is used by the Yoruba tribe in Nigeria for the treatment of several metabolic diseases, inflammatory diseases, wounds, coughs, and toothaches. Aim: This work evaluates the cardioprotective effects of M. cecropioides water extract on isoproterenol (ISO)-induced AMI in Wistar rats. Methodology: ISO (100 mg/kg, subcutaneous (s.c.)) was used to induce AMI in rats. Thirty rats (n = 5) were pretreated orally for seven days with normal saline (1.0 ml/kg/day, no-AMI control), normal saline + ISO (1.0 ml/kg/day + 100 mg/kg AMI, control), normal saline + M. cecropioides water extract (1.0 ml/kg/day + 500 mg/kg/day, non-AMI group), M. cecropioides water extract 500 and 1000 mg/kg/day, and captopril (5 mg/kg/po/day) before induction of AMI on the eighth and ninth days. Electrocardiographic changes, lipid peroxidation, biochemical enzyme profile, hematological, and histopathological changes were determined. Results: ISO significantly increased AST, ALT, lipid 15 profile, and oxidative stress marker (MDA). In addition, it caused ST segment elevation, increased heart rate, R-R interval, and degenerative changes in cardiac tissues. Pretreatment with M. cecropioides water extract (500 and 1000 mg/kg) significantly suppressed the biochemical enzyme profile and lipid peroxidation. It also significantly improved changes in histopathological and electrocardiographic imaging of the myocardium. Conclusion: The outcome of this work shows evidence that M. cecropioides water extract may have cardioprotective effects on AMI in rats.

Enzyme-assisted nanofiltration to enrich tannins from softwood bark extract

Softwood bark is a rich source of renewable chemicals, including phenolic compounds known as tannins. Tannins can be extracted from bark with hot water, but the yield can be relatively low, leading to dilute extracts. Next to tannin, a considerable amount of extracted dry matter comprised of carbohydrates, and bark carbohydrates limit the applicability of the extract in applications that demand high purity. This study used membrane filtration to refine and concentrate tannins produced from hot water extracts of softwood bark. Enzymatic hydrolysis of bark carbohydrates prior to membrane filtration was assessed as means to improve the separation of bark sugars from bark phenols. Enzymatic hydrolysis using an optimised enzyme mixture liberated 55% of bark carbohydrates mainly by degradation of pectin and other polysaccharides in spruce unrefined tannins. Separation of bark phenols from the enzyme-treated extract by precipitation at acidic pH and subsequent microfiltration produced low tannin yield. Instead, keeping bark phenols soluble at alkaline pH allowed us to concentrate them 15-fold with good and stable flux using nanofiltration. Additionally, enzymatically liberated sugars permeated well through the nanofiltration membrane, decreasing the free sugar content of the concentrated tannin from 31% to 7.4%. However, diafiltration did not seem to decrease the proportion of free sugars in the concentrate further. This enzyme-assisted nanofiltration concept was successfully upscaled to a pilot scale which was a promising result for improved industrial applicability of softwood bark tannins in the future.

Studies on the Catechin Constituents of Bark of Cinnamomum sieboldii.

Screening for bioactivity related to anti-infective, anti-methicillin-resistant Staphylococcus aureus (MRSA) and anti-viral activity, led us to identify active compounds from a methanol extract of Litsea japonica (Thub.) Juss. and the hot water extract of bark of Cinnamomum sieboldii Meisn (also known as Karaki or Okinawa cinnamon). The two main components in these extracts were identified as the catechin trimers (+)-cinnamtannin B1 and pavetannin B5. Moreover, these extracts exhibited anti-severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) activity. The structures of these catechin trimers were previously determined by chemical and spectroscopic methods. Pavetanin B5 has never been reported to be isolated as a pure form and has been obtained as a mixture with another component. Although other groups have reported the putative structure of pavetannin B5, preparation of the methylated derivative of pavetannin B5 in this study allowed us to obtain the pure form for the first time as the undecamethyl derivative and confirm its exact structure. Commercially available (+)-cinnamtannin B1 and aesculitannin B (C2'-epimer of cinnamtannin B1) both of which contained pavetannin B5 as a minor component, and C. sieboldii bark extract (approx. 5/2 mixture of (+)-cinnamtannin B1/pavetannin B5) were assessed for anti-SARS-CoV-2 activity. Both C. sieboldii bark extract and commercially available aesculitannin B showed viral growth inhibitory activity.

Corrosion Inhibition Mechanism Based on Adsorption Isotherm Model From Water Extract of Merkubung (Macaranga gigantea) Bark Extract on Mild Steel in Sulfuric Acid Solution

The phenolic chemicals found in water extract of Merkubung bark (WEMB) can be employed as corrosion inhibitors. The corrosion inhibition mechanism by WEMB can be studied using an adsorption isotherm model. The Langmuir adsorption isotherm model has an R 2 value that was closest to 1 one compared to the Freundlich, Temkin, Florry Huggins, and Frumkin adsorption isotherm models, as shown by an analysis of the adsorption isotherm model. Due to the interaction between the WEMB and the steel surface, the adsorption isotherm model reveals that the inhibitor of WEMB on the surface coating of mild steel tends toward chemisorption.

Qualitative and Quantitative Analysis of Phytochemicals and Anti-microbial Activity of Madhuca bourdillonii (Gamble) Lam.

The aim of the present study was to investigate the qualitative and quantitative analysis of Madhuca bourdillonii extracts and demonstrate its biological activities. The results of phytochemical analysis showed that the leaf water extract consists of more amount of total phenolics and tannins respectively of 7.4 mg of gallic acid/g and 113.28 mg%. Flavonoid content was found to be more in water extract of bark amounting to 40.73 mg of quercetin/g while the acetone extract of leaves showed more amounts of alkaloids accounting to 30.25 mg%. All the extracts of leaves and stems were evaluated for antimicrobial activity against gram-positive, gram-negative bacteria and pathogenic fungi using agar disc diffusion as well as well diffusion assays and subsequently MIC and MBC values were determined. Among all the bacteria tested, S. flexneri was most susceptible in both the assays exhibiting a zone of inhibition of 12.4 mm &amp; 14.2 mm and 12.2 mm &amp; 14.6 mm respectively for water and acetone extracts of bark. The IC50 values were found to be in the range of 4.52 - 31.34 mg/ml for all the tested bacteria. Among the fungal species tested, C. albicans was found to be susceptible with a zone of inhibition of 7.63 mm for bark water extract in disc diffusion assay and 12.36 mm with leaf ethanol extract in well diffusion assay. The IC50 values were found to be 12.37 - 31.65 mg/ml for C. albicans and F. oxysporium. The results show that Madhuca bourdillonii has excellent anti-bacterial properties which might help the development of novel lead drugs for treatment of various diseases.

Aktivitas Antioksidan dan Antidiabetes In Vitro Ekstrak Air Kulit Batang Kayu Manis (Cinnamomum burmannii) Asal Kota Jambi

Cinnamon (Cinnamomum burmannii) is an herbal plant that has a function, one of which is lowering glucose in the blood and warding off free radicals that cause oxidative stress. This study aims to determine the inhibitory activity of the enzyme compound α-glucosidase and the suppression of DPPH free radicals using the first, second, and third replications of cinnamon bark water extract (C. burmannii) as a natural source of antidiabetic drug candidates. The extraction method uses the infundation technique and is carried out using a spectronometer. The highest yield was obtained in the extraction of the first repeat, which is with an average of 0.674%, the yield did not differ markedly (p&gt;0.05) with the second and third repeats. The highest results of total phenolic testing were obtained in the second repeat extraction of 100.374 GAE g-1, the results differed markedly (p&lt;0.05) with the first and third repeats. The highest results of testing antioxidant activity were obtained at the extraction of the first repeat which was 9.012 mg of AAE g-1, the results differed markedly (p&lt;0.05) with the second and third repeats. The highest result of testing of enzyme inhibition activity α-glucosidase was found in the extraction of the first repeat which was 99.650%, the results did not differ markedly (p&gt;0.05) with the second and third repeats.

Screening and evaluation of cytotoxicity and antiviral effects of secondary metabolites from water extracts of Bersama abyssinica against SARS-CoV-2 Delta

BackgroundBersama abyssinica is a common herb in Africa, with diverse medical uses in different areas. The plant is well-known in Tanzania for treating respiratory disorders such as TB, tonsillitis, bronchitis, and asthma, and it has lately been utilized to treat COVID-19 symptoms. Water extract of leaf and stem bark has been registered as an herbal medication known as 'Coviba Dawa' in Tanzania for the relief of bacterial respiratory infections. The extracts, however, have not been scientifically tested for their anti-viral activities. The aim of this work was to test for the cytotoxicity and antiviral effects of bioactive ingredients from B. abyssinica extracts against the Delta variant of the SARS-CoV-2 coronavirus.MethodsB. abyssinica leaves and stem bark were dried under shade in room temperature and then pulverized to obtain small pieces before soaking into different solvents. One hundred grams of each, leaves and stem bark, were extracted in petroleum ether, dichloromethane, ethyl acetate and methanol. Water extract was obtained by decoction of stem bark and leaves into water. Phenols, flavonoids, tannins, and antioxidants were confirmed as components of the extracts. Analysis of polar extracts of bark stem bark and leaves was done. Antiviral screening and cytotoxicity experiments were conducted in a Biosafety Level 3 (BSL-3) Laboratory facility according to International Standard Operating Procedures (SOPs).ResultsBy the use of LC–MS/MS analysis, this study confirmed the existence of four phenolic compounds in B. abyssinica water extract; 2,4-di-tert-butylphenol, 4-formyl-2-methoxyphenyl propionate, 7,8-Dihydroxy-4-methylcoumarin, and 2,3, 6-trimethoxyflavone with antioxidant activity. This study showed that, while the water extracts of B. abyssinica had significant antiviral activity against SARS Cov2 virus, it showed no cytotoxicity effect on Vero E6 cells. In particular, the water extract (Coviba dawa) showed 75% while ethylacetate fraction of B. abyssinica leaves showed a 50% in vitro viral inhibition, indicating that these substances may be useful for the development of future anti-viral agents.ConclusionWe therefore recommend isolation of compounds for further profiling and development with a broader concentration range. We further recommend studies that determine the antiviral activity of extracts of B.abyssinica on other viral pathogens of clinical concern.

Assessment of Erythrophleum suaveolens (Brenan) leaves and stem bark water extracts antifungal potency on Aspergillus flavus incidence from maize (Zea mays L.) seeds

Aspergillus flavus has been associated with fungi attacks on stored maize seeds. Erythrophleum suaveolens had been reported to have antifungal properties which could protect some crops against fungi attack. This study aimed at evaluating the antifungal protection potency of both water extract of E. suaveolens leaves and stem bark on maize seeds varieties from A. flavus attack post six months of its application. Water extract of E. suaveolens leaves and stem barks (1, 10 and 100% concentration) were independently applied on four different varieties of maize seeds (OBA 98, OBA Super 6, SAMAZ 52 and SAMAZ 47) and stored alongside maize seeds without the extract application for 6 months. The fungal growth determination was carried out on Potato Dextrose Agar (PDA) media plates by placing maize seeds from both the group to which the extract was applied and those without the extract and incubating at 28 °C for 48 hours. The results indicated that all the maize seeds that the E. suaveolens leaves and stem bark water extract was applied at a varying concentration (1, 10 and 100%), recorded no growth of A. flavus unlike the maize seeds without the water extracts application which shows the incidence of A. flavus growth. In conclusion, E. suaveolens leaves and stem bark water extracts under varying concentration of 1, 10 and 100% had demonstrated to be an effective antifungal agent against A. flavus even after 6 months post application.

Phytochemical profile and antimicrobial activity of the leaves and stem bark of Symphonia globulifera L.f. and Allophylus abyssinicus (Hochst.) Radlk

IntroductionSymphonia globulifera and Allophylus abyssinicus are used in the management of skin rashes and sores, cough, malaria, digestive diseases, stomach ache, wounds and helminthic infections among others in Uganda, Kenya, Ethiopia, Cameroon. This study aimed at determining the phytochemical profile and antimicrobial activity of these two plants.MethodsThe stem bark and leaves of both plants were collected from Bwindi Impenetrable National Park and air-dried under shade at room temperature. Cold maceration, decoction and infusion with methanol, water and ethyl acetate as solvents were used in phytochemical extraction. Preliminary qualitative screening and thin layer chromatography were used for phytochemical profiling. Antimicrobial activity was analysed by agar well diffusion assay, broth macro-dilution assay and fractional inhibition concentration index (FICI).ResultsThe leaves and stem bark of both plants have a diverse set of phytochemical compounds of variable polarity including, tannins, alkaloids, flavonoids, saponins, quinones and anthraquinones among others. Generally, methanol and water extracts of S. globulifera and A. abyssinicus had in-vitro bactericidal activity against Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa but weak fungistatic activity against Candida albicans. Allophylus abyssinicus leaf water and S. globulifera leaf methanol extract combination had a synergistic activity (ΣFICI = 0.37) against S. aureus. Similarly, A. abyssinicus stem bark water extract and A. abyssinicus leaf water extract combination had an additive effect (ΣFICI = 1) against P. aeruginosa.ConclusionThe leaves and stem bark crude extracts of S. globulifera and A. abyssinicus possess a wide range of bioactive phytochemical compounds but have weak antimicrobial activity against S. aureus, E. coli, P. aeruginosa and C. albicans.

The Extract of Ilex cornuta Bark Promotes Bone Healing by Activating Adenosine A2A Receptor.

IntroductionBone fracture is a common reason causing human disability. The delay union and nonunion rates are approximately 5–10% despite patients receiving active treatment. Currently, there is a limited number of drugs directly accelerating bone healing, especially direct extracts from plants. Moreover, the pharmacological effects of Ilex cornuta bark are still unknown. This study aimed to explore the effects and mechanisms of Ilex cornuta bark in bone healing.Methods and ResultsFirst, the promoting effects of Ilex cornuta bark on bone healing were verified by the mice femur fracture model as Ilex cornuta bark increased the callus formation and enhanced the biomechanical stability during the bone healing process. Second, the target gene of Ilex cornuta bark in bone healing identified by bioinformatics analysis and immunofluorescence validation was ADORA2A. Third, 410 main compound compositions of Ilex cornuta bark were explored by a non-target metabolomic analysis, where 190 of them were neg ion mode, and 220 were pos ion mode. Molecular docking was used to predict the regulatory effect of the compounds on adora2a (adenosine A2A receptor), and ursonic acid had the lowest binding energy with adora2a. Finally, nfkb1 was the transcription factor (TF) of adora2a, and ursonic acid also had the lowest binding energy by bioinformatic analysis and molecular docking.ConclusionOverall, Ilex cornuta bark water extract was a new plant extract on promoting bone healing; in addition, the mechanism of it might be activating adora2a though Nfkb1.

Investigation of anaesthetic potentials of various extracts of Annona muricata (sour sop) in Wister albino rat and dog

ObjectivesLocal and general anaesthetics currently used in clinical practice are not absolutely safe and efficacious. Hence two or more drugs are used for induction and maintenance of general anaesthesia. MethodsIn view of this, local and general anaesthetic potentials of Annona muricata extracts were investigated prospectively in laboratory using rat and dog. A total of 15 animals comprising 6 rats (3 males; 3 females) and 9 dogs (5 males; 4 females) were used. Secondary metabolites in root bark, leaf, stem bark and seed of Annona muricata were qualitatively and quantitatively determined. Methanol and water extracts were tested for induction and maintenance of surgical anaesthesia in rat and dog. The dose of the extracts (1250 mg/kg body weight of rat) that produced deep anaesthesia in rats was translated to 150, 170 and 150 mg/kg of root bark methanol extract (RBME), stem bark water extract (SBWE) and seed water extract (SWE), respectively. Each extract was administered to female and male dog for induction and maintenance of anaesthesia. Laparatomy was carried out via linea alba, and the length of small intestine (220 cm) and large intestine (32 cm) were measured using measuring ruler. ResultsPhenols and tannins were significantly lower (p < 0.05) as compared to saponins, flavonoids, alkaloids and glycosides. The median lethal dose (LD50) of methanol extract was < 5000 mg/kg in female and > 5000 mg/kg in male rats, respectively. Sedation, anaesthesia, male mounting and death were observed within 4 days of extract administration in the female rats, However, 12.5 mg/kg showed significant (p < 0.05) local anaesthesia on the test surgical sites. The male administered 170 mg/kg of SBWE showed salivation, significantly decreased respiratory rate, and loss of palpebral reflex, excretion, urination that characterized plane III; stage III of anaesthesia (deep anaesthesia) which lasted for 67 min. ConclusionsAqueous extract of Annona muricata have very potent local and general anaesthetic effects for a period of over 1 h. The observed effects may be due to presence of secondary metabolites.

The Inhibitory Activity and Kinetics of α-Glucosidase by Toona sinensis Stem Bark Extracts

Research on the potential of the Surian tree (Toona sinensis) for medicine has been carried out, especially for the leaves. However, the bark section has not been done much. This study aimed to determine the inhibitory activity of -glucosidase and IC50 extract as well as the fraction of surian bark as antidiabetic in vitro. The reflux method with water at 90oC and maceration using 70% ethanol at room temperature was carried out to obtain aqueous and ethanol extracts. Furthermore, the ethanol extract was fractionated successively using n-hexane, diethyl ether, and ethyl acetate. Phytochemical screening test showed that the aqueous extract contained flavonoids, saponins, and tannins. Meanwhile, the 70% ethanol extract and its fraction showed terpenoid content, in addition to flavonoid compounds, saponins, and tannins. The best -glucosidase inhibition was shown by 70% ethanol extract, which was 70.45 ppm followed by ethyl acetate fraction, n-hexane fraction, diethyl ether fraction, and water extract of surian bark with values of 81.96 g/mL, 98.76 g/mL, respectively. , 140.25 g/mL, and 242.85 g/mL. Kinetics of -glucosidase inhibition showed that 70% ethanol extract of surian bark inhibited through a non-competitive inhibition mechanism, characterized by a decrease in Vmax from 8.29x10-3 mM/min to 1.65x10-3 mM/min and a decrease in Km from 0.17 mM to 0.03 mM.

Evaluation of antioxidant activities and quantitative estimation of phytochemicals in Kandelia candel (L.) Druce

Kandelia candel, a mangrove belonging to the family Rhizophoraceae, the whole plant is reported to have anti-diabetic properties and was studied for the evaluation of in vitro antioxidant and antidiabetic study. Total Phenolic Content (TPC), Total Flavonoid Content (TFC) and Total Alkaloid Content were quantitatively estimated by using standard protocols. The study evaluated the antioxidant activity of the extract and the method was employed for the evaluation of antioxidant activity are DPPH radical scavenging assay, reducing power assay and Phosphomolybdenum assay. Potent antioxidant activities were shown by the acetonitrile extract and water extract of leaf and stem in all the assays. Acetonitrile extract of bark showing highest DPPH scavenging activity (IC50 = 31.84 g/ml). Plant extract showing poor, reducing power. The better reduction of molybdenum was shown by acetonitrile extract of bark followed by leaf (617.33 ± 4.44). Chloroform, acetonitrile and water extract of leaf and bark of Kandelia candel, were evaluated for antidiabetic activity by alpha-amylase inhibition assay, Water and acetonitrile extract show good inhibition. Highest TPC and TFC were obtained for the acetonitrile extract of bark (237.6 ± 1.06 and 1277.19 ± 3.41). These findings show that the polyphenolic constituents in the extracts are responsible for free radical scavenging capacity. The results of this study indicate that this plant is medicinal with prominent antioxidant activities.

Advantages of MW-assisted water extraction, combined with steam explosion, of black alder bark in terms of isolating valuable compounds and energy efficiency

“Green” extraction of black alder bark using deionized water as an alternative to organic solvents and microwave (MW) - induced heating instead of convective/conductive heating was studied. An extractor of original construction with the MW capacity of 2.4 kW, equipped with a pressurized extraction chamber (V = 1350 cm3) and a condenser section, was used. The MW-assisted heating of the suspension up to the desirable temperature was performed with a uniform high rate of ~ 30 ℃ min−1. The yield of the black alder bark water extracts obtained by MW-assisted extraction varied from 15.4% to 26.4% (on bark dry matter) increasing with increasing extraction temperature (70–150 ℃) and increasing duration of the isothermal step of extraction (0–30 min). The electricity consumption per dry weight of obtained products needed for MW-assisted heating of the substrate containing suspension varied from 6.2 to 32.0 kWh kg−1 being higher at higher extraction temperature and longer duration of isothermal heating step. UHPLC-ESI-MS/MS, GC-FID, Py-GS/MS/FID, UV spectroscopy methods revealed that the main constituents of the obtained black alder bark water extracts were diarylheptanoids, condensed tannins, carbohydrates, organic acids, flavonoids, lignin related phenols. The MW-induced depolymerization of alder bark cell wall constituents (hemicellulose, lignin) evidenced by Py-GC/MS/FID, GC-FID, wet chemistry analyses of extracts and bark residues after extraction, resulted in the disruption of the bark cell wall and isolation of metabolites bound within it by microwaves-assisted extraction (MAE). Therefore, the black alder bark water extracts, obtained by MAE at 70–110 ℃, compared to those isolated by advanced accelerated solvent extraction (ASE) at a given temperature, have higher diversity and higher contents of different groups of phenolic extractives, including a higher content of their major class in alders – diarylheptanoids. The increase of the extraction temperature above 110 ℃ and the duration of extraction up to 30 min led to an increase of the content of carbohydrates and noticeable decrease of phenolics content in extracts, including the dominating diarylheptanoid - oregonin. The content of oregonin, having a high antioxidant activity and valuable biological activities, was in focus of our research and practical interest. MAE with dynamic heating to 90 ℃ without keeping of isothermal heating is the most attractive for obtaining of oregonin-enriched extracts, containing up to 57% of oregonin, in contrast to ASE water extracts with the maximum oregonin content of 39%. In this regime, two-fold less energy consumption (7 vs 15 kWh kg−1) and two and a half times more productivity (1.5 vs 0.6)% min−1 was achieved in comparison to the case of the ASE method used as reference.

In vitro antidiabetic and anti-inflammatory activities of the bark of Ehretia acuminata R.Br.

Ehretia acuminata is native to Southeast Asia, America, and Africa. It is commonly used as fodder and in quite a variety of medicinal applications. E. acuminata is widely used in India, but there are few reports in the literature of studies on its biological properties. In this study, the antidiabetic and anti-inflammatory activities of plant E. acuminata was evaluated. The antidiabetic activity of the different extracts was measured by α-amylase and α-glycosidase inhibition method. The anti-inflammatory activity was evaluated by the egg albumin of hen. Petroleum ether, chloroform, ethyl acetate, ethanol and water extracts of bark of E. acuminata was evaluated for in-vitro anti-inflammatory and antidiabetic activity. Ethyl acetate and ethanol extract showed significant anti-inflammatory effects (IC 50 170 and 172 µg/mL respectively). Chloroform is the only extract that showed significant inhibition against the antidiabetic effect (IC 50 42-45 µg/mL). The findings suggest that the bark of E. acuminata contains potential antidiabetic and anti-inflammatory compounds, which could be tested as drug candidates against diabetic and inflammation-related pathological processes in medicinal chemistry studies.

Enhancing Biobutanol Production from biomass willow by pre-removal of water extracts or bark

Aiming to understand the importance of debarking on the controlled utilization of phenolic-rich willow biomass, biobutanol was produced from it by using Clostridium acetobutylicum. Acid-catalysed steam explosion and enzymatic hydrolysis (EH) were investigated before the acetone-butanol-ethanol (ABE) fermentation. The hydrolysable sugar yield and ABE fermentation efficiency were found to decline progressively from willow wood (WW) to HWE WB (hot water extracted willow biomass), WB (willow biomass) and the WW + HWE (willow wood plus the artificial willow bark water extracts), indicating that the pre-removal of water extracts or the bark can significantly improve ABE yield. Notably, the ABE productivity of WW achieved 12.7 g/L at the solvent yield of 31%, and the butanol concentration (i.e. 8.5 g/L) generated by WW is relatively high among the reported lignocellulosic-derived biomass. Additionally, it is hypothesized that under acidic conditions and high temperatures the fructose present in willow water extracts form hydroxymethylfurfural during steam explosion, which then spontaneously condenses with phenolic substances of willow bark to form a solid furanic precipitate. The formed furanic precipitates play inhibitory role in the enzymatic hydrolysis and are thereby deleterious to the ABE fermentation.

Endogenous metabolic content of the cutting positions and ndole-3-butyric acid influence rooting of Toona ciliata var. pubescens stem cuttings

Toona ciliata var. pubescens (family Meliaceae) is an endangered species of mahogany endemic to China. It is now under Class II protection, and stem cuttings are an important means for its clonal propagation. However, the metabolic changes that occur in the cuttings during adventitious root formation and how these are influenced by indole-3-butyric acid (IBA) are still unclear. This study investigated the influence of cutting positions (top, middle and base) on the rooting ability and the associated metabolic changes during adventitious root formation. We compared treatment with 800 mg l−1 IBA with controls. The results showed that the rooting percentage, taproots per cutting, and longest root length differed significantly depending on the cutting position. Base cuttings had the best rooting ability and exhibited the highest average rooting percentage, the longest roots, and most taproots per cutting. The contents of soluble sugar, starch, non-structural carbohydrates (NSCs) and soluble proteins, and the peroxidase (POD) activity, were significantly higher in base cuttings than in middle and top cuttings; however, polyphenol oxidase (PPO) activity did not differ significantly among the positions. Metabolic changes occurred during the cutting process. The levels of POD and PPO activities increased significantly until 20 days after planting, suggesting that this period is key for the induction of adventitious rooting in this species. In the rooting process, IBA promoted an increase in the contents of soluble sugar, starch, NSCs and soluble proteins in the stem cuttings and it also increased the activities of POD and PPO. Bark-water extract from the stem cuttings inhibited the germination of Chinese cabbage seeds in a concentration-dependent manner, irrespective of the cutting position.