Jakob Avi Shimshoni

Agricultural Research Organization- Volcani Center

Cannabis is used to treat various medical conditions, and lines are commonly classified according to their total concentrations of Δ9-tetrahydrocannabinol (THC) and cannabidiol (CBD). Based on their ratio of total THC to total CBD, cannabis cultivars are commonly classified into high-THC, high-CBD, and hybrid classes. While cultivars from the same...

Cannabis sativa L. is used to treat a wide variety of medical conditions, in light of its beneficial pharmacological properties of its cannabinoids and terpenes. At present, the quantitative chemical analysis of these active compounds is achieved through the use of laborious, expensive, and time-consuming technologies, such as high-pressure liquid-...

Cannabis based products are widely used for various medicinal conditions. Currently, the most common method to identify and quantify cannabinoids are liquid chromatographic methods coupled to UV-VIS or mass spectrometric detectors. As cannabinoids are fluorescent compounds, fluorescent-based detection methods are gaining increasing interest. Conseq...

Cannabinoids are commonly identified and quantified using chromatographic based methods. In the present study, fluorescence spectroscopic method coupled with Parallel Factor Analysis (PARAFAC) modeling was developed and validated as a simple and fast alternative technique for identification and quantification of major cannabinoids. A PARAFAC model...

Introduction: Cannabis sativa L. inflorescences are rich in secondary metabolites, particularly cannabinoids. The most common techniques for elucidating cannabinoid composition are expensive technologies, such as high-pressure liquid chromatography (HPLC). Objectives: We aimed to develop and evaluate the performance of a novel fluorescence spect...

Introduction Cannabis sativa L. inflorescences are rich in cannabinoids and terpenes. Traditional chemical analysis methods for cannabinoids and terpenes, such as liquid and gas chromatography (using UV or MS detectors), are expensive and time‐consuming. Objectives This study explores the use of Fourier transform near‐infrared (FT‐NIR) spectroscop...

Myrtus communis is a Mediterranean shrub cultivated in Israel for traditional, ceremonial use only, with more than 98 % of the crop biomass, equivalent to 26–27 tons per ha per annum, considered agricultural waste. Therefore, potentially profitable use for this excess is being highly sought. As Myrtus is also known for its unique terpene and terpen...

Introduction Cannabis sativa L. inflorescences are widely used in the medicinal field as treatments for a variety of symptoms and illnesses due to their unique phytochemicals such as cannabinoids and terpenes. Common postharvest procedures for cannabis inflorescence include trimming, followed by drying, curing, and subsequent storage. The postharve...

Background Bacterial strains in the rhizosphere may secrete an array of volatile organic compounds (VOCs), many of which are vital for inter- and intra-kingdom signaling, modulating microbe-microbe and microbe-plant interactions. In this study, we tested the plant growth promoting effect of VOCs emitted by Bacillus sp. NYG5 on several plants, focus...

A limited number of studies have examined how drying conditions affect the cannabinoid and terpene content in cannabis inflorescences. In the present study, we evaluated the potential of controlled atmosphere drying chambers for drying medicinal cannabis inflorescence. Controlled atmosphere drying chambers were found to reduce the drying and curing...

The effort to maintain cannabinoid and terpene levels in harvested medicinal cannabis inflorescence is crucial, as many studies demonstrated a significant concentration decrease in these compounds during the drying, curing, and storage steps. These stages are critical for the preparation and preservation of medicinal cannabis for end-use, and any d...

Myrtus communis is a Mediterranean shrub cultivated in Israel for traditional, ceremonial use only, with more than 98% of the crop biomass, equivalent to 26–27 tons per ha per annum, considered agricultural waste. Therefore, potentially profitable use for this excess is being highly sought. As Myrtus is also known for its unique terpene and terpeno...

BACKGROUND In recent years, hydroponically cultivated basil has gained extensive popularity over soil‐based cultivation. Evidence for potential differences between both cultivation methods, in terms of resistance to biotic and abiotic stress factors, storage properties and shelf‐life, is still lacking and the potential effect of cultivation method...

BACKGROUND Varroa control is essential for the maintenance of healthy honey bee colonies. Overuse of acaricides has led to the evolution of resistance to those substances. Studies of the short‐term acaricidal effects and safety of various lithium (Li) salts recently have been reported. This study examined the long‐term in vitro and in vivo bee toxi...

BACKGROUND Terpene, eugenol and polyphenolic contents of basil are major determinants of quality, which is affected by genetics, weather, growing practices, pests and diseases. Here, we aimed to develop a simple predictive analytical method for determining the polyphenol, eugenol and terpene content of the leaves of major Israeli sweet basil cultiv...

Although amitraz is one of the acaricides most commonly applied within beehives, to date, its time-dependent oral toxicity in honeybees has not been investigated, due to amitraz’s instability in aqueous media. In aqueous media such as honey, amitraz rapidly forms a continuously changing tertiary mixture with two of its major hydrolysis products, DM...

Pyrrolizidine alkaloids (PAs) are genotoxic carcinogenic phytotoxins mostly prevalent in the Boraginaceae, Asteraceae and Fabaceae families. Heliotropium species (Boraginaceae) are PA-producing weeds, widely distributed in the Mediterranean region, that have been implicated with lethal intoxications in livestock and humans. In Israel, H. europaeum,...

Honeybees are exposed to a wide range of pesticides for long periods via contaminated water, pollen and nectar. Some of those pesticides might constitute health hazards in a time- and dose-dependent manner. Time-dependent toxicity profiles for many applied pesticides are lacking, despite the fact that such profiles are crucial for toxicological eva...

Throughout the world, more than six billion people consume milk and milk products yearly. The safety and quality of dairy milk are regularly monitored in most countries worldwide. The Israeli monitoring program of chemical residues in milk has not changed in the last decades, focusing only on major veterinary drugs and few selected environmental co...

Postharvest application of fungicides is commonly applied in order to reduce food loss. Prochloraz is currently the only postharvest fungicide registered in Israel and Europe in avocado fruits. Due to its unfavorable toxicological properties, prochloraz will be banned from the end of 2020 for future postharvest usage and therefore a substitute cand...

The increased demand of high quantity and quality of cherry tomatoes requires the application of a wide range of pre-harvest pesticides. The application of dozens of pre-harvest pesticides frequently results in multiple pesticide residues, to which the end consumer is exposed. Incorrect usage of these pesticides may result in hazardous food contami...

Objective To report the use of gas chromatography–mass spectrometry to confirm a diagnosis of synthetic cannabis toxicosis in a dog and to describe the clinical course of the intoxication. Case Summary An 11‐year‐old neutered female Boxer dog was referred due to acute onset of vomiting, ataxia, dull mentation, and delirium that progressed to gener...

Beehive products such as honey, beeswax and recently pollen have been regarded for many years as appropriate sentinels for environmental pesticide pollutions. However, despite yearly application of hundreds of approved pesticides in agricultural fields, only a minor fraction of these organic compounds were actually detected in honey and beeswax sam...

MRM transition and optimized parameters for pesticides analyzed by LC-MS/MS. (PDF)

Linear regression F-test of LogD vs time. (PDF)

MRM transition and optimized parameters for the pesticides analyzed by GC-MS/MS with positive EI ionization. (PDF)

5-Methoxy-2-aminoindane (MEAI) is a novel psychoactive aminoindane derivative, exerting euphoric, alcohol-like tipsy experience and reduced desire to consume alcoholic beverages. Our previous toxicological evaluation of MEAI in rats, clearly indicated MEAI's potential to be further evaluated as a promising binge mitigating agent due to its favorabl...

In February 2014 a new law was approved by the Israeli parliament, namely the Control of Animal Feed Law. The law intends to regulate the production and marketing of animal feed. In preparation for the law's implementation in 2017, we have assessed the current feed and food safety challenges in Israel in recent years in association with the presenc...

The epidemiological investigation of an incident that killed 98 sows (170-220 kg b.w.) out of a total of 180 sows was described. The sows were at the beginning (1-2 weeks) of their lactation period. The incident started with the sudden death of 8 sows and lasted 20 days. No clinical signs of disease were observed prior to the death of the first ani...

Pyrrolizidine alkaloids are among the most common poisonous plants affecting livestock, wildlife, and humans. Exposure of humans and livestock to toxic pyrrolizidine alkaloids through the intake of contaminated food and feed may result in poisoning, leading to devastating epidemics. During February 2014, 73 mixed breed female beef cows from the Gal...

3,4-Methylenedioxy-N-methylamphetamine (MDMA) has been shown to be effective in the treatment of post-traumatic stress disorder (PTSD) in numerous clinical trials. In the present study, we have characterized the neurochemical binding profiles of three MDMA-benzofuran analogues (1-(benzofuran-5-yl)-propan-2-amine, 5-APB; 1-(benzofuran-6-yl)-N-methyl...

The Israeli feed safety legislation, which came to prominence in the early 1970's, has undergone a major change from simple feed safety and quality regulations to a more holistic concept of control of feed safety and quality throughout the whole feed production chain, from farm to the end user table. In February 2014 a new law was approved by the I...

Inspection of feed and animal derived food products is of utmost importance in providing safe feed and food products. Chemical as well as microbial contaminants are frequently encountered in various food and feed commodities thereby potentially endangering public health as well as animal well-being. In February 2014 a new law, namely the Control of...

Dehydro pyrrolizidine alkaloids (dehydro PAs) are carcinogenic phytotoxins prevalent in the Borginaceae, Asteracea and Fabacea families. Dehydro PAs enter the food and feed chain by co-harvesting of crops intended for human and animal consumption as well as by carry-over into animal-based products such as milk, eggs and honey. Recently the occurren...

Abstract 3-Methyl-methcathinone (3-MMC) is a novel, synthetic cathinone analog, recently linked to poisoning events among recreational users. The lack of pharmacological data on 3-MMC, prompted us to explore its pharmacokinetic profile as well as its effect on feeding behavior, weight gain, and serum biochemistry. 3-MMC was administered to male pig...

Pyrrolizidine alkaloids (PAs) are carcinogenic and genotoxic phytochemicals found exclusively in angiosperms. The ingestion of PA-containing plants often results in acute and chronic toxicities in man and livestock, targeting mainly the liver. During February 2014, a herd of 15-18 months old mixed breed beef cattle (n=73) from the Galilee region in...

Pyrrolizidine alkaloids (PAs) are carcinogenic and genotoxic phytochemicals found exclusively in angiosperms. The ingestion of PA-containing plants often results in acute and chronic toxicities in man and livestock, targeting mainly the liver. During February 2014, a herd of 15−18-month-old mixed-breed beef cattle (n = 73) from the Galilee region i...

all-trans-Retinoic acid (atRA), the active metabolite of vitamin A, induces gene transcription via binding to nuclear retinoic acid receptors (RARs). The primary hydroxylated metabolites formed from atRA by CYP26A1, and the subsequent metabolite 4-oxo-atRA, bind to RARs and potentially have biological activity. Hence CYP26A1, the main atRA hydroxyl...

Novel acyl-urea containing compounds, processes of preparing same, compositions containing same and uses thereof in the treatment of neurological diseases and disorders such as epilepsy, neuropathic pain, bipolar disorder, status epilepticus, chemically-induced convulsions and/or seizure disorders, febrile convulsions conditions, metabolic disturba...

Ionophores are used as feed additives for the control of coccidiosis and growth promotion in farm animals. Reports of maduramicin toxicosis in farm animals are scarce. The present work describes an acute maduramicin toxicosis affecting 22 pregnant gilts, 2 pregnant sows and 2 boars, resulting in a total mortality of 65% within 2 days. The clinical...

A 17-month-old male King Charles cavalier was presented with acute onset of generalized body tremors and facial twitching after being exposed to 2 different compounds of the pyrethrins/pyrethroids group and imidacloprid. Bifenthrin toxicity was confirmed by gas chromatography mass spectrometry. Initial therapy consisted of diazepam, metacarbamol an...

Ticks are obligatory blood parasites responsible for transmitting a variety of diseases to humans and animals. Since ticks share similar morphological features, accurate identification of tick species is important for control and management of disease-associated risks. Here, we report the application of gas chromatography mass spectrometry for anal...

Anticoagulant rodenticides are frequently a cause of poisoning of domestic animals, wildlife, and human beings. A toxicosis in 6,000 laying hens caused by the malicious addition of unknown amounts of coumatetralyl bait as well as the insecticides aldicarb, methomyl, and imidacloprid in the drinking water, was investigated in the current study. In o...

Cuticular fatty acids (CFA) are important constituents of the arthropod exoskeleton, serving as structural and defense components, and participating in intra-species communication. Here we describe for the first time a comparative analysis of the CFA profiles of three tick species of the genus Rhipicephalus: R. annulatus, R. bursa and R. sanguineus...

Silage is an important feed source for intensive dairy herds worldwide. Fungal growth and mycotoxin production before and during silage storage is a well-known phenomenon, resulting in reduced nutritional value and a possible risk factor for animal health. With this in mind, a survey was conducted to determine for the first time the occurrence of m...

The potent hepatotoxin and carcinogen aflatoxin B1 (AFB1) is a common mycotoxin contaminant of grains used in animal feeds. Aflatoxin M1 (AFM1) is the major metabolite of AFB1 in mammals, being partially excreted into milk, and is a possible human carcinogen. The maximum permitted concentration of AFM1 in cows' milk is 0.05 μg/kg in Israel and the...

All-trans-retinoic acid (atRA), the major active metabolite of vitamin A, plays a role in many biological processes, including maintenance of epithelia, immunity, and fertility and regulation of apoptosis and cell differentiation. atRA is metabolized mainly by CYP26A1, but other P450 enzymes such as CYP2C8 and CYP3As also contribute to atRA 4-hydro...

The bisdichloroacetyldiamine WIN 18,446 reversibly inhibits spermatogenesis in many species, including humans; however, the mechanism by which WIN 18,446 functions is unknown. As retinoic acid is essential for spermatogenesis, we hypothesized that WIN 18,446 might inhibit retinoic acid biosynthesis from retinol (vitamin A) within the testes by inhi...

Whole brain cholinesterase activity was measured in 26 species of wild birds in Israel, and compared to depressed cholinesterase activities of birds known to having been exposed to certain organophosphorus and carbamate insecticides. The purpose of the study was to establish a reference range of normal whole brain cholinesterase activities, which w...

A series of glycinamide conjugates and N-methoxy amide derivatives of valproic acid (VPA) analogs and constitutional isomers were synthesized and evaluated for anticonvulsant activity. Of all compounds synthesized and tested, only N-methoxy-valnoctamide (N-methoxy-VCD) possessed better activity than VPA in the following anticonvulsant tests: maxima...

Valproic acid (VPA) is the most widely prescribed epilepsy treatment worldwide, but its mechanism of action remains unclear. Our previous work identified a previously unknown effect of VPA in reducing phosphoinositide production in the simple model Dictyostelium followed by the transfer of data to a mammalian synaptic release model. In our current...

All-trans-retinoic acid (atRA) is the active metabolite of vitamin A. atRA is also used as a drug, and synthetic atRA analogs and inhibitors of retinoic acid (RA) metabolism have been developed. The hepatic clearance of atRA is mediated primarily by CYP26A1, but design of CYP26A1 inhibitors is hindered by lack of information on CYP26A1 structure an...

The ability of chronic valproate (VPA) to reduce arachidonic acid (AA) turnover in brain phospholipids of unanesthetized rats has been ascribed to its inhibition of acyl-CoA synthetase (Acsl)-mediated activation of AA to AA-CoA. Our aim was to identify a rat Acsl isoenzyme that could be inhibited by VPA in vitro. Rat Acsl3-, Acsl6v1- and Acsl6v2-,...

Valproic acid (VPA) is used to treat epilepsy and bipolar disorders, as well as for migraine prophylaxis. However, its clinical use is limited by two life-threatening side effects: hepatotoxicity and teratogenicity. To develop a more potent and safer second-generation VPA drug, the urea derivatives of four VPA analogs (2-ethyl-3-methylpentanoyl ure...

Valproic acid (VPA, 1) is a major broad spectrum antiepileptic and central nervous system drug widely used to treat epilepsy, bipolar disorder, and migraine. VPA's clinical use is limited by two severe and life-threatening side effects, teratogenicity and hepatotoxicity. A number of VPA analogues and their amide, N-methylamide and urea derivatives,...

The purpose of this study was to evaluate the stereoselective anticonvulsant activity, neurotoxicity, pharmacokinetics, and teratogenic potential of two stereoisomers of valnoctylurea (VCU), a central nervous system (CNS)-active urea derivative of valnoctic acid, which is a constitutional isomer of valproic acid (VPA). VCU stereoisomers (2S,3S)-VCU...

Propylisopropylacetic acid (PIA) is a constitutional isomer of valproic acid (VPA). It has previously been found to be a weak antiepileptic, but in common with mood stabilizers, causes inositol depletion and growth cone spreading, suggesting the basis of a new series of mood stabilizers. To assess this possibility, we have compared the effects of r...

A composite time lapse movie (Quicktime) of typical growth cones recorded at 1 frame per 30 s for up to 15 min.

Although valproic acid (VPA) is used extensively for treating various kinds of epilepsy, it causes hepatotoxicity and teratogenicity. In an attempt to develop a more potent and safer second generation to VPA drug, the amide derivatives of the tetramethylcyclopropyl VPA analogue, 2,2,3,3-tetramethylcyclopropanecarboxamide (TMCD), N-methyl-TMCD (MTMC...

The purpose of this study was to evaluate the anticonvulsant activity and teratogenic potential of branched aliphatic acylureas represented by isovaleroylurea (IVU), pivaloylurea (PVU) and 3,3-dimethylbutanoylurea (DBU), as potential second-generation drugs to valproic acid (VPA). The anticonvulsant activity of IVU, PVU, and DBU was determined in m...

As part of our ongoing research on potential new antiepileptic drugs (AEDs), a series of tetramethylcyclopropanecarboxamide derivatives containing benzene ring were designed, synthesized, and evaluated for anticonvulsant activities in the murine maximal electroshock (MES) and subcutaneous pentylenetetrazole (scMet) seizure tests. The most potent co...

Valproic acid (VPA) is a major antiepileptic drug (AED); however, its use is limited by two life-threatening side effects: teratogenicity and hepatotoxicity. Several constitutional isomers of VPA and their amide and urea derivatives were synthesized and evaluated in three different anticonvulsant animal models and a mouse model for AED-induced tera...

Valproic acid (VPA) is an effective antiepileptic drug with an additional activity for the treatment of bipolar disorder. It has been assumed that both activities arise from a common target. At the molecular level, VPA targets a number of distinct proteins that are involved in signal transduction. VPA inhibition of inositol synthase reduces the cel...

Antiepileptic drugs (AEDs) are often utilized in the treatment of neuropathic pain. The major AED valproic acid (VPA) is of particular interest as it is thought to engage a variety of different neural mechanisms simultaneously. However, the clinical use of VPA is limited by two rare but life-threatening side effects: teratogenicity and hepatotoxici...

The tumor cells toxicity of the antiepileptic drug valproic acid (VPA) has been associated with the inhibition of histone deacetylases (HDACs). We have assessed, in comparison to VPA, the HDACs inhibition and tumor cells cytotoxicities of CNS-active VPA's constitutional isomers, valnoctic acid (VCA), propylisopropylacetic acid (PIA), diisopropylace...