The fabrication and assessment of mosquito repellent cream for outdoor protection.

Mosquito-borne infections like dengue, malaria, chikungunya, etc. are a nuisance and can cause profound discomfort to people. Due to the objectional side effects and toxicity associated with synthetic pyrethroids, N,N-diethyl-3-methylbenzamide (DEET), N,N-diethyl phenylacetamide (DEPA), and N,N-di ethyl benzamide (DEBA) based mosquito repellent products, we developed an essential oil (EO) based mosquito repellent cream (EO-MRC) using clove, citronella and lemongrass oil. Subsequently, a formulation characterization, bio-efficacy, and safety study of EO-MRC were carried out. Expression of Anti-OBP2A and TRPV1 proteins on mosquito head parts were studied by western blotting. In-silico screening was also conducted for the specific proteins. An FT-IR study confirmed the chemical compatibility of the EOs and excipients used in EO-MRC. The thermal behaviour of the best EOs and their mixture was characterized by thermogravimetric analysis (TGA). GC-MS examination revealed various chemical components present in EOs. Efficacy of EO-MRC was correlated with 12% N,N-diethyl benzamide (DEBA) based marketed cream (DBMC). Complete protection time (CPT) of EO-MRC was determined as 228 min. Cytotoxicity study on L-132 cell line confirmed the non-toxic nature of EO-MRC upon inhalation. Acute dermal irritation study, acute dermal dose toxicity study, and acute eye irritation study revealed the non-toxic nature of EO-MRC. Non-target toxicity study on Danio rerio confirmed EO-MRC as safer for aquatic non-target animals. A decrease in the concentration of acetylcholinesterase (AChE) was observed in transfluthrin (TNSF) exposed Wistar rats. While EO-MRC did not alter the AChE concentrations in the exposed animals. Results from western blotting confirmed that Anti-OBP2A and TRPV1 proteins were inhibited in TNSF exposed mosquitoes. Mosquitoes exposed to EO-MRC showed a similar expression pattern for Anti-OBP2A and TRPV1 as the control group. In silico study revealed eight identified compounds of the EOs play significant roles in the overall repellency property of the developed product. The study emphasizes the mosquito repellent activity of EO-MRC, which could be an effective, eco-friendly, and safer alternative to the existing synthetic repellents for personal protection against mosquitoes during field conditions.

Syzygium cumini (L.) Skeels extracts; in vivo anti-nociceptive, anti-inflammatory, acute and subacute toxicity assessment.

ETHNOPHARMACOLOGICAL RELEVANCE: Syzygium cumini (L.) Skeels has been extensively used in the ancient medical system of Pakistan, India, Bangladesh, and Sri Lanka to combat diabetes, inflammation, and renal disorders. These health-promoting aspects of S. cumini are related to bioactive metabolites such as phenolic acids, anthocyanins, tannins, and flavonoids. AIM OF THE STUDY: Earlier to this study, we have reported S. cumini extracts as potential sources of bioactive compounds bearing antioxidant and anti-inflammatory properties. However, prior further suggesting S. cumini fruit extracts for consumption against inflammatory disorders, it was mandatory to validate the claim and explore toxicity of the extracts. This study aims to determine the in vivo anti-nociceptive, anti-inflammatory, acute, and subacute toxicity properties of S. cumini crude extracts, followed by identifying and quantifying bioactive metabolites. MATERIAL AND METHODS: In the present study, the anti-nociceptive and anti-inflammatory potential of S. cumini sequential crude extracts were evaluated using formalin and glutamate-induced paw licking method in mice. The acute and sub-acute toxicity assessment of active extract was performed by oral administration in rats. An acute toxicity trial was performed with two different doses, i.e., 2000 mg/kg and 3000 mg/kg for consecutive 14 days, whereas a sub-acute toxicity study was conducted at doses of 750 mg/kg and 1500 mg/kg for the next 28 days. Identification of bioactive compounds was performed using HPLC, and at the end, in silico docking calculations of identified compounds were performed. RESULTS: The 100% methanolic extract (SCME) protected the mice from painful stimulation of formalin and glutamate in a dose-dependent manner with the maximum effect of 49% and 67% at 200 mg/kg, respectively, followed by moderate and non-influential effects of 50% methanolic extract and dichloromethane (DCM) extracts when compared to control, i.e., normal saline. The results of acute toxicity recorded LD50 of SCME over 3000 mg/kg, and no antagonistic effects were recorded during the subacute study when SCME dispensed at the rate of 750 mg/kg and 1500 mg/kg. SCME was found to induce no adverse effects to kidney, heart, liver, spleen, and paired lungs examined by hematological, serum biochemical, histological analysis. HPLC analysis of S. cumini 100% methanolic extracts revealed the presence of delphinidin 3-glucoside, peonidin-3,5-diglucoside, scopoletin, and umbelliferone at the concentration of 127.4, 2104, 31.3, 10.4 µg/g whereas in 50% methanolic extract, the quinic acid, catechin, and myricetin were present at the concentration of 54.9, 63.7, 12.3 µg/g, respectively. Umbelliferone and scopoletin are newly reported compounds in the present study. In silico docking calculations of these compounds indicated the potential of anti-nociceptive and anti-inflammatory activities. CONCLUSIONS: These findings validate that S. cumini fruit extracts are a rich source of bioactive compounds that needs to be considered to enhance biological activities with lesser side effects.

Assessment of in vitro and in vivo antimalarial efficacy and GC-fingerprints of selected medicinal plant extracts.

A hallmark of mortality and morbidity, malaria is affecting nearly half of the world's population. Emergence of drug-resistant strains of malarial parasite prompts identification and evaluation of medicinal plants and their constituents that may hold the key to a new and effective anti-malarial drug. In this context, nineteen methanolic extracts from seventeen medicinal plants were evaluated for anti-plasmodial potential against Plasmodium falciparum strain 3D7 (Chloroquine (CQ) sensitive) and INDO (CQ resistant) using fluorescence based SYBR-Green assay and for cytotoxic effects against mammalian cell lines. Leaf extract of two plants showed promising in vitro anti-malarial activity (Pf3D7 IC50 ≤ 10 µg/ml); one plant extract showed good activity (Pf3D7 IC50 = 10.1-20 µg/ml); seven were moderately active (IC50 = 20.1-50 µg/ml), four plant extracts showed poor activity (PfD7 IC50 = 50.1-100 µg/ml) and five extracts showed no activity up to IC50 = 100 µg/ml. Further, six extracts were found equipotent to PfINDO (resistance index ranging 0.4-2) and relatively nontoxic to mammalian cell lines HEK293 (cytotoxicity index ranging 1.4-12.5). Based on good resistance and selectivity indices, three extracts were evaluated for in vivo activity in Plasmodium berghei ANKA infected mice at a dose of 500 mg/kg and they showed significant suppression of P. berghei parasitemia. Further, these active plant extracts were fractionated using silica-gel chromatography and their fractions were evaluated for anti-plasmodial action. Obtained fractions showed enrichment in antimalarial activity. Active fractions were analyzed by gas chromatography and mass-spectrometery. Results suggests that the three active plant extracts could serve as potent source of anti-malarial agent and therefore require further analysis.

FEMA GRAS assessment of natural flavor complexes: Clove, cinnamon leaf and West Indian bay leaf-derived flavoring ingredients.

In 2015, the Expert Panel of the Flavor and Extract Manufacturers Association initiated the safety re-evaluation of over 250 natural flavor complexes (NFCs) used as flavor ingredients. This publication, 4th in a series focusing on the safety evaluation of NFCs, presents an evaluation of NFCs rich in hydroxyallylbenzene and hydroxypropenylbenzene constituents using a procedure initially published in 2005 and updated in 2018 that evaluates the safety of naturally occurring mixtures for their intended use as flavoring ingredients. The procedure requires the characterization of the chemical composition for each NFC and subsequent organization of the constituents into defined congeneric groups. The safety of each NFC is evaluated using the conservative threshold of toxicological concern (TTC) approach together with studies on absorption, metabolism and toxicology of the NFC and its constituent congeneric groups. By the application of this procedure, seven NFCs, derived from clove, cinnamon leaf and West Indian bay leaf were affirmed as "generally recognized as safe (GRAS)" under their conditions of intended use as flavor ingredients. An eighth NFC, an oleoresin of West Indian bay leaf, was affirmed based on its estimated intake, which is below the TTC of 0.15 µg/person per day for compounds with structural alerts for genotoxicity.

In vivo assessment of anticoagulant and antiplatelet effects of Syzygium cumini leaves extract in rabbits.

BACKGROUND: Syzygium cumini (L.) Skeels. is one of the very popular traditionally used medicinal plants with numerous pharmacological activities including antioxidant, hypoglycemic and anti-inflammatory. However, actions of S. cumini on blood coagulation and other parameters of blood were poorly pharmacologically studied. Therefore, aim of this present investigation is to examine the effects of methanolic extract of S. cumini on blood coagulation and anticoagulation factors in healthy white albino rabbits at different doses. METHODS: Blood samples were drawn twice during this study and biochemical assays were performed to determine the effect on different parameters such as coagulation, anticoagulation, hematological, Protein C (PC) and thrombin antithrombin (TAT) complex and platelet aggregation. RESULTS: The results showed significant increase in RBCs, hemoglobin, hematocrit and platelets counts up to 1.4 × 103/cm, 2.2 g/dl, 6%, 248.2 × 103/cm respectively. While, thrombin and bleeding time were also prolonged in dose dependent manner which is highly significant (p ≤ 0.005) as compared to control. Similarly, highly significantly increased (p ≤ 0.005) in levels of protein C, thrombin antithrombin complex at dose of 500 mg/kg were observed. Whereas, levels of platelets aggregation and fibrinogen were decreased at high doses. CONCLUSION: The obtained findings of hematological and coagulation tests concludes possibly S. cumini possess anticoagulant and antiplatelet effects.

Phenolic contents-based assessment of therapeutic potential of Syzygium cumini leaves extract.

Syzygium cumini (S. cumini) is an evergreen tropical plant that is well recognized for its therapeutic potential of common diseases. In this study, the therapeutic potential and biomedical application of S. cumini are assessed in vitro and in vivo to find its effectiveness for different complications. The methanolic crude extract of S. cumini leaves were screened for total phenolic and flavonoid content. In vitro, the DPPH scavenging assay, XTT assay, prothrombin and activated partial thromboplastin time were used to assess antioxidant, cytoprotective and thrombolytic activity of the S. cumini extract, respectively. The anti-inflammatory potential and the analgesic activity of the S. cumini extract were analyzed in rabbits by the Carrageenan induced paw edema method and the writhing method, respectively. Phytochemical analysis showed the presence of considerable amounts of total phenolic (369.75 ± 17.9 mg GAE/g) and flavonoid (75.8 ± 5.3 mgRE/g) content in the S. cumini extract. The DPPH assay demonstrated a higher antioxidant potential (IC-50 value of 133 µg/ml), which was comparable to the IC-50 of ascorbic acid (122.4 µg/ml). Moreover, the S. cumini extract showed a dose dependent cytoprotective effect against H2O2 treated bone marrow mesenchymal stem cells (BM-MSCs). S. cumini also possesses significant anticoagulant activity with a prothrombin time of 28.3 ± 1.8 seconds vs 15.8 ± 0.2 seconds of control, p<0.05. The leaf extract also demonstrated an analgesic effect in rabbits as indicated by the decrease in writhing (12.2 ± 1.7 control vs. 3.7 ± 0.6 treated) and anti-inflammatory activity in rabbits paw with a protection against inflammation of 64.1 ± 2.4%. Our findings suggest that the methanolic extract of S. cumini leaves has antioxidant, cytoprotective, anticoagulant, analgesic and anti-inflammatory properties, and therefore, can be applied for treating cardiovascular diseases and cancers.

Rapid quantification of clove (Syzygium aromaticum) and spearmint (Mentha spicata) essential oils encapsulated in a complex organic matrix using an ATR-FTIR spectroscopic method.

Essential oils (EOs) are often encapsulated in various and complex matrices to protect them against potential degradation or to control their release. To achieve an optimum use in food products, their rapid and precise quantification after encapsulation and storage is required. Hence, a rapid ATR-FTIR method was developed and tested with two encapsulated essential oils (EOs): clove (Syzygium aromaticum) and spearmint (Mentha spicata);. Despite, the complexity of the matrix, this method coupled with univariate or multivariate regression models exhibited high potential for global quantification of the two encapsulated EOs. For clove EO, in relation to the major presence of eugenol and eugenol acetate, an analysis based on a unique band (1514 cm-1) was sufficient to obtain a good prediction with RMSEP value of 0.0173 g of EO per g of matrix. For spearmint oil which is characterized by numerous terpenoid compound, three bands (799, 885, and 1680-1676 cm-1) were suitable for a good prediction with RMSEP value of 0.0133. ATR-FTIR method was compared with a reference gas chromatography FID quantitative method in an EO release experiment and its efficiency was evaluated through modeling by the Avrami equation. Beside time saving, the ATR-FTIR method was also capable of monitoring the EO profile. This method could be easily adapted as a routine analysis in the EOs industry as quality control.

In vivo assessment of antidiabetic and antioxidative activity of natural phytochemical isolated from fruit-pulp of Eugenia jambolana in streptozotocin-induced diabetic rats.

OBJECTIVES: Eugenia jambolana (E. jambolana) is well known for its antidiabetic potential. The aim of the present study was to investigate the antidiabetic and antioxidative effect of an active compound (FIIc) isolated from fruit-pulp of E. jambolana in streptozotocin (45 mg/kg body weight)-induced diabetic rats. METHODS: FIIc was isolated from the crude aqueous extract of fruit-pulp by ion-exchange column chromatography and high-performance column chromatography. Detailed UV, NMR, and IR spectra suggested that FIIc is α-hydroxy succinamic acid. FIIc was orally administered to diabetic rats at a dose of 10, 15, and 20 mg/kg body weight (mg/kg bwt.) to determine its effective dose. Thereafter, effective dose was administered to 8 weeks to determine its antidiabetic and antioxidative activity by estimation of glycemic index, lipid profile, key enzymes of carbohydrate metabolism, and oxidative stress parameters. RESULTS: Administration of 15 mg/kg dose daily for 8 weeks led to significant (P < 0.001) fall in fasting blood glucose. Treatment with FIIc (15 mg/kg bwt.) showed significant improvement (P < 0.001) in all the biochemical parameters. DISCUSSION: The results demonstrate that FIIc possesses significant antidiabetic and antioxidative activity.

The effectiveness of clove extracts in the inhibition of hydroxyl radical oxidation-induced structural and rheological changes in porcine myofibrillar protein.

Oxidation is a major cause of protein quality deterioration during the storage and processing of food. This study investigated the effects of clove extract (CE) on structural and rheological changes in porcine longissimus myofibrillar proteins (MP) and the effects of oxidizing radicals produced by a Fenton reaction system (FRS). Increased oxidation time was accompanied by increased carbonyl content, reduced Ca-ATPase activity, decreased enthalpy of denaturation, decreased thermal transition temperatures (P<0.05), and increased protein susceptibility to thermal aggregation. The addition of CE significantly inhibited carbonyl formation (P<0.05), enhanced solubility and thermal stability, and improved the gel formation ability (storage modulus, loss modulus) of MP. The protective effect of CE on protein denaturation was demonstrated by its efficacy in maintaining Ca-ATPase activity and decreasing the degree of protein aggregation. Overall, the hydroxyl radical-induced loss of the structural and functional properties of MP was significantly reduced by the presence of CE.

Assessment of metal contents in spices and herbs from Saudi Arabia.

In the recent years, there has been a growing interest in monitoring heavy metal contamination of spices/herbs. Spices and herbs are sources of many bioactive compounds that can improve the tastes of food as well as influence digestion and metabolism processes. In the present study, the levels of some essential and toxic elements such as iron (Fe), zinc (Zn), copper (Cu), chromium (Cr), manganese (Mn), cobalt (Co), nickel (Ni), lead (Pb), and cadmium (Cd), present in common spices/herbs that were purchased from the local market in Saudi Arabia, were analyzed by atomic absorption spectroscopy after digestion with nitric acid/hydrogen peroxide mixture. Samples from the following spices/herbs were used: turmeric, cloves, black pepper, red pepper, cumin, legume, cinnamon, abazir, white pepper, ginger, and coriander. The concentration ranges for the studied elements were found as 48.8-231, 4.7-19.4, 2.5-10.5, below detection level (BDL)-1.0, 8.8-490, 1.0-2.6, and BDL-3.7 µg g(-1) for Fe, Zn, Cu, Cr, Mn, Ni, and Pb, respectively, while Cd and Co levels were below the detection limit. Consumers of these spices/herbs would not be exposed to any risk associated with the daily intake of 10 g of spices per day as far as metals Fe, Zn, Cu, Cr, Mn, Ni, and Pb are concerned.

Kinetic assessment and effect on developmental physiology of a trypsin inhibitor from Eugenia jambolana (Jambul) seeds on Helicoverpa armigera (Hübner).

A trypsin inhibitor was purified from the seeds of Eugenia jambolana (Jambul) with a fold purification of 14.28 and a yield recovery of 2.8%. Electrophoretic analysis of E. jambolana trypsin inhibitor (EjTI) revealed a molecular weight of approximately 17.4 kDa on 12% denaturing polyacrylamide gel electrophoresis with or without reduction. EjTI exhibited high stability over a wide range of temperatures (4-80 °C for 30 min) and pH (3.0-10.0) and inhibited trypsin-like activities of the midgut proteinases of fourth instar Helicoverpa armigera larvae by approximately 86%. Feeding assays containing 0.05, 0.15, and 0.45 (% w/w) EjTI on functionally important fourth-instar larvae indicated a dose-dependent downfall in the larval body weight as well as on extent of survival. The nutritional analysis suggests that EjTI exerts toxic effects on H. armigera. Dixon plot analysis revealed competitive inhibition of larval midgut proteinases by EjTI, with an inhibition constant (Ki ) of approximately 3.1 × 10(-9) M. However, inhibitor kinetics using double reciprocal plots for trypsin inhibition demonstrated a mixed inhibition pattern. These observations suggest the potential of E. jambolana trypsin inhibitor protein in insect pest management.

When trade law meets public health evidence: the World Trade Organization and clove cigarettes.

A recent trade dispute between the USA and Indonesia, overseen by the World Trade Organization, challenges piecemeal approaches to tobacco regulation.

Assessment of antioxidant capacity and cytotoxicity of selected Malaysian plants.

Thirteen Malaysian plants; Artocarpus champeden, Azadirachta indica, Fragaria x ananassa, Garcinia mangostana, Lawsonia inermis, Mangifera indica, Nephelium lappaceum, Nephelium mutobile, Peltophorum pterocarpum, Psidium guajava and Syzygium aqueum, selected for their use in traditional medicine, were subjected to a variety of assays. Antioxidant capability, total phenolic content, elemental composition, as well as it cytotoxity to several cell lines of the aqueous and ethanolic extracts from different parts of these selected Malaysian plants were determined. In general, the ethanolic extracts were better free radical scavengers than the aqueous extracts and some of the tested extracts were even more potent than a commercial grape seed preparation. Similar results were seen in the lipid peroxidation inhibition studies. Our findings also showed a strong correlation of antioxidant activity with the total phenolic content. These extracts when tested for its heavy metals content, were found to be below permissible value for nutraceutical application. In addition, most of the extracts were found not cytotoxic to 3T3 and 4T1 cells at concentrations as high as 100 microg/mL. We conclude that although traditionally these plants are used in the aqueous form, its commercial preparation could be achieved using ethanol since a high total phenolic content and antioxidant activity is associated with this method of preparation.

Safety assessment of Syzygium aromaticum flower bud (clove) extract with respect to testicular function in mice.

The flower buds of Syzygium aromaticum (clove), a common food flavor, have been used as indigenous medicine for the treatment of male sexual disorders in Asian countries. However, the possible mechanism(s) by which it acts at testicular level remain obscure. Therefore, to investigate its effect on testicular function, chronic oral exposure of hexane extract of flower buds of Syzygium aromaticum in three doses (15 mg, 30 mg, and 60 mg/kg BW) were evaluated for a single spermatogenic cycle (35 days) in Parkes (P) strain mice. The treatment did not induce systemic toxicity at the doses tested. Lower dose (15 mg) of the extract increased the activities of Delta(5) 3 beta-HSD and 17 beta-HSD, and serum level of testosterone. The higher doses (30 and 60 mg) of extract inhibited these parameters and induced non-uniform degenerative changes in the seminiferous tubules associated with decrease in daily sperm production and depletion of 1C (round and elongated spermatids) population. Taken together these results suggest biphasic action of hexane extract of Syzygium aromaticum flower bud on testicular function, thereby advocating a cautious use of the flower bud as an aphrodisiac in indigenous systems of medicine in Asian countries.

Antidiabetic drugs used in Europe prior to the discovery of insulin.

Many therapeutic agents had been used for the treatment of diabetes mellitus before insulin was discovered and several hundred plants have shown some extent of antidiabetic activity. This study tries to explore which agents were most widely used in Europe in the pre-insulin era. According to the scientific literature and the proprietary drug industry around 1900, more than 100 agents were considered to have hypoglycemic activity. Most of them seem to have been used only occasionally while some others were recommended and marketed to a large extent. Among the medicinal plants, Syzygium cumini (syn. S. jambolanum, Eugenia jambolana), Vaccinum myrtillus and Phaseolus sp. were most common, and other frequently used agents were opium, opium alkaloids, other alkaloids like quinine or Belladonna alkaloids, salicylates, alkaline substances like sodium (bi)carbonate and even strong poisons like arsenic or uranium salts. Syzygium jambolanum seed powder seems to be one of the most intensively studied antidiabetic agents of plant origin.