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Floral diversity of Croton, the second largest genus in Euphorbiaceae, is currently under-explored. Several clades demonstrate an unusual floral morphology, e.g., lower or higher stamen number, bilateral symmetry and reduced ovary, but have never been investigated in a comparative study with typical Croton. This study examined morphology and ontogeny of flowers in nine Croton species from different clades within the genus with light and scanning microscopy, resin sectioning and micro-computed tomography. In staminate flowers, great variations of stamen number and arrangement are observed. The ancestral androecium likely consisted of two or more whorls with the outermost antepetalous stamen whorl developing centrifugally. Modification by reduction of the antepetalous whorl resulted in an outer alternipetalous stamen whorl in Croton section Moacroton, subgenus Quadrilobi. Several species in the subgenus Geiseleria show an independent reduction of stamen numbers by absence of a centrifugal development with the antepetalous whorl the first whorl to develop. Petal losses are observed in the distantly related C. setiger and C. dioicus. Chaotic stamen arrangement is found in C. celtidifolius (subgenus Adenophylli) as a result of a secondary stamen increase. In pistillate flowers, reduction of carpel numbers happened three times in the subgenus Geiseleria. C. monanthogynus has a bicarpellate ovary, while in C. setiger and C. michauxii the ovary is monocarpellate. Reduction of carpel number is linked with merism change and perianth reduction. The ovary in C. michauxii has basal placentation which is unique among all Croton. Moreover, strong bilateral sepals and nectaries are observed in species from section Julocroton. Therefore, the floral diversity of some species in the genus Croton could be explained by developmental modification of an ancestral form via reduction, rearrangement of stamen whorls, and symmetry shifts. [ABSTRACT FROM AUTHOR]

• Croton is a genus with over 1300 species that are endemic to the tropics and subtropics. • Diterpenoids make up 67.2 % of the compounds reported in this genus. • Based on predicted drug-likeness, 38 % of Croton compounds obey Lipinski's rule of five. • Croton compounds have comparable physicochemical properties to FDA-approved drugs. The genus Croton (Euphorbiaceae family) is constituted of approximately 1300 species with remarkable ethnomedicinal backgrounds supported by extensive pharmacological studies alongside over 900 compounds associated with some of the activities. However, there is no systematic review of the compounds' physicochemical features in tandem with their absorption, distribution, metabolism, extraction, and toxicity (ADMET) to corroborate both ethnomedicinal and pharmacological potential. This study focused on a virtual analysis of the physicochemical-ADMET properties of compounds from the genus Croton reported between 1990 and 2024. Various electronic databases, namely Google, Google Scholar, Scopus, ScienceDirect, Biomed Central, and Pubmed, were used to search for information related to the chemistry and pharmacology of Croton species. The physicochemical, ADMET and Scaffold information of the reported croton compounds were obtained from SWISSADME, pKCSM, and Data Warrior webservers, which were then analyzed by Origin Pro 2023 statistical software. Diterpenoids (67.2 %), alkaloids (11.1 %), sesquiterpenes (4.7 %), flavonoids (3.2 %), other terpenoids (Sesterterpenoid and triterpenoids; 2.7 %), monoterpenoids (1.7 %), megastigmane glycosides (2.2 %), proanthocyanidins (0.8 %), and other assorted compounds (6.4 %) make up the total of 900 compounds reported among the genus Croton between 1990 and 2024. Based on principal component analysis (PCA) results (PC1 and PC2, with total variances of 43.79 % and 16.50 %, respectively), most of these compounds have the same chemical space as FDA-approved medications. The biological activity that was most frequently reported was cytotoxicity (52 %) followed by anti-inflammatory actions (13 %). After the ADME screening, 38 % of the Croton compounds met the predetermined criteria for drug-likeness while toxicity analysis cleared 35.487 %, as nontoxic. The primary appropriate therapeutic candidates identified by the post- ADMET analysis were clerodanes, kauranes, labdanes and abietanes compounds, with respective ratios of 10, 10, 10, and 5 %. Alkaloids (5 %), crotofolanes at 20 %, and sesquiterpene majorly at 40 % were too determined to be appropriate therapeutic candidates. The majority of these compounds are drug-like with recommended ADME/Tox profiles. Given the promising cytotoxic potential of compounds from the genus Croton , further studies are warranted to determine their therapeutic applications and optimize their pharmaceutical development. [Display omitted] [ABSTRACT FROM AUTHOR]

Croton antisyphiliticus Mart. is a plant popularly used in folk medicine by traditional communities from Brazilian savannah to treat general inflammation. According to ethnopharmacological data, this specie can be considered a source of biologically active molecules for the development of new drugs. Thereby, this study reports the results of the dereplication approach of C. antisyphiliticus roots extracts and the in vivo evaluation of its potential antinociceptive and anti-inflammatory in albino Swiss mice. Based on HPLC coupled to Q-Exactive Orbitrap Mass Spectrometer and using GNPS, a total of thirteen polyphenolic compounds were noticed, including four compounds that have been reported for the first time in the genus Croton. Ethanolic and aqueous roots extracts demonstrated a dose-dependent inhibition for the number of writes, reduced pain induced by formalin and hyperalgesia induced by carrageenan. These extracts also reduced paw edema, cell migration, and myeloperoxidase activity, with effects similar to indomethacin and dexamethasone drugs. [ABSTRACT FROM AUTHOR]

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Objective(s): Cognizant of the harsh chemical method of nanoparticles synthesis, researchers are shifting towards the green phyto-mediated synthetic approaches. We herein report the green synthesis of Ag NPs and Co3O4 NPs using silver nitrate solution and cobalt nitrate solution as precursors added to aqueous extract of Croton Macrostachyus leaf extract to evaluate their antibacterial activity. Materials and Methods: The Characterization of the biosynthesized NPs were carried out by using spectroscopic techniques as X-ray diffraction (XRD), UV-Vis spectroscopy, Fourier Transform Infrared (FTIR), and scanning electron microscopy (SEM). Results: The average crystallite size of Ag NPs was found to be 12.62 nm from the XRD data, indicating a cubic crystal structure whereas that of Co3O4 NPs was found to be 12.75 nm, indicating a cubic spinel crystal structure. The energy band gap for Ag NPs and Co3O4 NPs were 3.38 eV, and 3.34 eV respectively. The SEM images showed non-homogeneity of particles distribution with irregular geometries attributable to their shape and size for Ag NPs whereas spherical as well as irregular geometries attributed to non-homogeneity of the particles for Co3O4 NPs. The FTIR identifies the functional groups of the bioactive molecules that were actively involved as stabilizing and capping agents to prevent agglomeration of Ag NPs and Co3O4 NPs. The agar-well diffusion method was employed to evaluate the antibacterial activities of the produced nanoparticles against gram-positive (S. aureus and E. faecalis) and gram-negative (E. coli, S. typhimrium) bacterial strains. Conclusion: The biosynthesized nanoparticles showed promising antibacterial activities with Ag NPs exhibiting the best inhibition activities towards all bacteria species. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The reported investigations were aimed at establishing anticancer potential of the leaf extracts from Croton dictyophlebodes (CDE), C. kilwae (CKE) and C. longipedicellatus ssp austrotanzanicus (CLE). In vitro cytotoxicity assays of the extracts were performed against human laryngeal cancer cell line (HEp-2) and human breast cancer cell line (MCF-7), while in vivo toxicological studies were done using Swiss albino mice (Mus musculus) following the Organization for Economic Cooperation and Development guideline number 423 of 2001. Results for in vitro assays revealed that CDE and CLE induced cytotoxicity to MCF-7 and HEp-2 cell lines at EC50 values of 86 and 63 μg/mL, respectively, while CKE was inactive to HEp-2 cells at 100 μg/mL. For in vivo studies, mice were given calculated doses based on globally harmonized standards and monitored for 14 days to observe signs of toxicity. Haematological analysis was also carried out to obtain information on changes in blood conditions. The findings showed that LD50 for CKE and CDE were > 2000 mg/kg, while for CLE was 175 mg/kg body weight (b. w.). The oral administration of CDE and CKE did not reveal significant changes in haematological parameters of treated mice, while CLE provoked some. Thus, the studied extracts may be considered potential cancer remedies with safety precautions that warrant further investigations. [ABSTRACT FROM AUTHOR]

The expenses of medical services are increasing across the globe. As a result, pressure is placed on government and insurance companies' budgets. The amounts of money collected are not enough to cover the claim payments. Therefore, it threatens the sustainability of the health insurance companies due to the mismatch of income and expenditures. This study aimed to model and forecast claim payments for the national health insurance fund (NHIF) in Tanzania. The claim payment data for the period of 2001-2021 from NHIF were used in building the ARIMA model. It was proven that ARIMA (0, 2, 2) is the most accurate model for forecasting the claim payments from 2022 to 2031. Furthermore, numerical results show that the claim payments for NHIF will grow by 68% by 2031. [ABSTRACT FROM AUTHOR]

The species endemics Croton micradenus, Croton myricifolius and Croton spiralis among others the genus, integrate the main populations in this Oriental region of Cuba. A wide range of uses are attributed to the species of the genus, among which medicinal uses stand out. Among the secondary metabolites present in Croton species, nonpolar compounds constitute a group that has shown biological activity against pathogenic microorganisms. In this sense, our objective is to compare the chemical composition, determine the major components and the potential chemo-taxonomic markers; as well as, the antimicrobial activity of the hexanic extracts of the leaves and stems of the three species, by GC-MS and pharmacological assays. The samples tested showed activity against at least two of the four microorganisms studied. The presence of octacosanol and palmitic acid (majority components), as oleic acid, stigmasterol and sitosterol in the extracts of the three species confer responsibility for the biological activity expressed. [ABSTRACT FROM AUTHOR]

Trichomes are key functional traits that protect plants against abiotic stresses, herbivores and pathogens. In addition to their ecological roles, trichomes show high morphological variability in many lineages, providing useful characters for species characterization and taxon delimitation. Here, we focus on trichomes in Croton , a megadiverse genus (c. 1200 spp.) of Euphorbiaceae, in which these structures are ubiquitous and exhibit significant variation in form, location on the plant body, density and function. Owing to their functional and taxonomic relevance and the current need for further standardization of their terminology and classification, we revised previous trichome classifications used in the genus. We also provide new trichome data by expanding taxon sampling and using different methodological approaches in plant anatomy to improve understanding of the structural patterns of the trichome types present in the genus. On the basis of our results and literature review, we propose a new classification for trichomes in Croton based on well-defined parameters; this clarifies existing redundancies, is consistent with anatomical evidence and can be easily updated as new types are revealed in future surveys. This contribution will improve communication among taxonomists and promote more meaningful morphological comparability across systematics studies, including those focusing on morphological evolution and functional traits. [ABSTRACT FROM AUTHOR]

The article offers information about the achievements of Dr. N.P. Balakrishnan, a prominent figure in Indian botany. It details his educational background, career in the Botanical Survey of India, and contributions to the field, including his work on the family Euphorbiaceae in India. This article is part of a series called "Living Legends of Indian Botany," which aims to honor and recognize outstanding botanists.

Over the years, ethnopharmacological and phytochemical investigations have been conducted to understand the potential effects of the Croton genus on several diseases. It has been revealed that these terpenoid-rich species traditionally used to treat gastrointestinal diseases, heal wounds, and relieve pain have a wide range of therapeutic effects; however, those used to treat diabetes, as well as their action mechanisms, have not been reviewed so far. Therefore, the main objective of this review was to compile all Croton species that have shown pharmacological effects against diabetes and describe their action mechanisms. Through a search of the literature, 17 species with hypoglycemic, antihyperglycemic, antilipidemic, antihypertensive, antioxidant, and anti-inflammatory effects were found. Among the mechanisms by which they exerted these effects were the inhibition of α-glucosidases, the promotion of insulin secretion, and the increase in glucose uptake. Interestingly, it was found that some of them may have antihyperglycemic properties, although there were no ethnopharmacological reports that support their traditional use. Moreover, others only presented studies on their hypoglycemic effect in fasting, so further works are encouraged to describe the mechanisms involved in lowering fasting blood glucose levels, such as hepatic glucose production, especially for C. cajucara, C. cuneatus, C. gratissimus var. gratissimus, C. guatemalensis, and C. membranaceus. It is expected that this review contributes to the plant science knowledge of the genus, and it can be used in future references on the identification and development of new molecules/phytomedicines that help in the treatment of diabetes. [ABSTRACT FROM AUTHOR]

Using essential oils to control vectors, intermediate hosts, and disease-causing microorganisms is a promising approach. The genus Croton in the family Euphorbiaceae is a large genus, with many species containing large amounts of essential oils, however, essential oil studies are limited in terms of the number of Croton species investigated. In this work, the aerial parts of C. hirtus growing wild in Vietnam were collected and analyzed by gas chromatography/mass spectrometry (GC/MS). A total of 141 compounds were identified in C. hirtus essential oil, in which sesquiterpenoids dominated, comprising 95.4%, including the main components β-caryophyllene (32.8%), germacrene D (11.6%), β-elemene (9.1%), α-humulene (8.5%), and caryophyllene oxide (5.0%). The essential oil of C. hirtus showed very strong biological activities against the larvae of four mosquito species with 24 h LC50 values in the range of 15.38–78.27 μg/mL, against Physella acuta adults with a 48 h LC50 value of 10.09 μg/mL, and against ATCC microorganisms with MIC values in the range of 8–16 μg/mL. In order to provide a comparison with previous works, a literature survey on the chemical composition, mosquito larvicidal, molluscicidal, antiparasitic, and antimicrobial activities of essential oils of Croton species was conducted. Seventy-two references (seventy articles and one book) out of a total of two hundred and forty-four references related to the chemical composition and bioactivity of essential oils of Croton species were used for this paper. The essential oils of some Croton species were characterized by their phenylpropanoid compounds. The experimental results of this research and the survey of the literature showed that Croton essential oils have the potential to be used to control mosquito-borne and mollusk-borne diseases, as well as microbial infections. Research on unstudied Croton species is needed to search for species with high essential oil contents and excellent biological activities. [ABSTRACT FROM AUTHOR]

Croton (Euphorbiaceae) is a very large genus of over 1 200 species of herbs, shrubs and trees occurring mainly in the (sub)tropics. The major diversity of Croton is within the Neotropics; and there are comparatively few species in South-East Asia. This contribution provides a revision of Croton from the Sumatran region in Indonesia, including descriptions and a determination key. In total sixteen species are recognized for Sumatra, including four species new to science, C. beccarii, C. scalaeus, C. simalurensis, and C. viridifolius. Two new synonyms and lectotypification of numerous names are also included. Besides a taxonomic treatment, a molecular analysis, using the nuclear ribosomal internal transcribed spacer (ITS), based on former data extended with Sumatran species, was performed to create a phylogeny that places the Sumatran species in a phylogenetic context. In total 13 new sequences were created, which were combined with 56 sequences obtained from GenBank. The results from the phylogenetic analysis, based on Bayesian inference, are in line with the phylogeny as published for mainly the Australian species of Croton by Van Ee et al. (2015). [ABSTRACT FROM AUTHOR]

The phytochemical study of Croton lauioides Radcl.-Sm. & Govaerts led to the isolation of twenty-one compounds (1 – 21) , including three diterpenoids (1 – 3), two triterpenoids (4 – 5), eight flavonoids (6 – 13), three lignans (14 – 16), four aromatic compounds (17 – 20), and one glycolipid (21). Their structures were determined by NMR spectroscopic analysis as well as comparison with previously reported data. All compounds (1 – 21) were isolated from C. lauioides for the first time, while twelve compounds 3 , 5 , 9 – 10 , 12 – 18 , and 21 were firstly isolated from the family Euphorbiaceae, and two compounds 2 , and 20 were isolated from the genus Croton for the first time. Meanwhile, the chemotaxonomic significance of these isolated compounds from the whole plant of C. lauioides was also discussed. • Twenty-one compounds (1 – 21) have been isolated from Croton lauioides for the first time. • Twelve compounds 3 , 5 , 9 – 10 , 12 – 18 , and 21 were firstly isolated from the family Euphorbiaceae. • The chemotaxonomic significance of the isolates was discussed. [ABSTRACT FROM AUTHOR]

The use of plants has grown constantly worldwide, being a rich source of compounds that serve as established treatments for various diseases and conditions. This paper discusses the elemental composition and the level of environmental risk of heavy metals of selected medicinal plants. The extracts are investigated by energy dispersive X-ray fluorescence, a non-destructive, fast, multi-element, highly accurate and environmentally friendly analysis compared to other elementary detection methods. The studied plants Croton dioicus and Phoradendron villosum are native to Mexico. Both showed high levels of Cu and Ni, while their extracts present levels within the permissible range. [ABSTRACT FROM AUTHOR]

The present work performed to study the toxic effects of the crude plant extracts of Croton tiglium seeds on some histological changes of the terrestrial snail species Monacha obstructa. The molluscicidal efficacy of ethanol and acetone extracts of Croton tiglium seeds were tested against the adult snails of M. obstructa (L. Pfeiffer) (Gastropoda: Hygromiidae) at four concentrations using contact technique under laboratory conditions for seven days. Also, the impact of crude seed extracts was studied on some histological changes of the land snail, M. obstructa. The results revealed that the hexane and ethanolic extracts of croton exhibited molluscicidal activities against M. obstructa land snails. The ethanolic extract displayed the highest potency where LC50 was (0.08 %) while the LC50 of hexane extracts was (0.12 %). Histological inspections of the digestive gland and foot of snails exposed to LC50 croton extract showed that the digestive tubules showed various destruction, shrinkage in different types of cells lining the digestive tubules, marked increase in the width of most of the digestive tubules lumen and filled with secretory materials, rupture of basement membrane and the intertubular loose connective tissue between the digestive tubules showed necrosis. The histological alterations in the foot included rupture of the epithelial covering with necrosis, destruction of muscular tissue and necrosis of connective tissue with presence of dark brown pigment. Thus, these results indicated that croton seed crude extracts possessed molluscicidal potential for controlling the land snail with more future studies to develop and ensure its wider applicability as a molluscicide. [ABSTRACT FROM AUTHOR]

Croton gratissimus Burch. is a deciduous shrub used in traditional medicines and a local traditional herbal tea in South Africa. C. gratissimus is used in treating several disease conditions, including cough, influenza, colds, malaria, fever, bleeding gums, chest complaints, indigestion, skin inflammation, earache, respiratory disorders, diabetes, and oedema. This review focuses on the botanical attributes, distribution, traditional uses, phytochemistry, nutritional constituents and pharmacological properties of C. gratissimus. A wide-range search of previous literature on various scientific databases, including Google, Google Scholar, Science Direct, PubMed, Scopus, theses, dissertations, and ethnobotanical textbooks, was conducted. The search showed that C. gratissimus has several reported traditional uses, with over 55 compounds identified and isolated from it. Some of the compounds include cembrane-, trachylobane- and pimarane-type diterpenes, triterpenes, sesquiterpenes, sterols, flavonoids and flavonoids glycosides. The bioactive compounds had biological activities such as antioxidant, antiplasmodial, anticancer, antibacterial, vasorelaxant, and cholinesterase inhibitory action. C. gratissimus is reported to have antimicrobial, antidiabetic, antiparasitic, antiviral, antioxidant, haemostatic, anticancer, anti-inflammatory, toxicity, and immune-boosting properties. Other pharmacological activities of C. gratissimus include analgesic, anticonvulsant, antipyretic, nephroprotective, and ulcerogenic properties. C. gratissimus' nutritional constituents include total sugar, protein, amino acids, fat, dietary fibre, carbohydrate, energy, ash, moisture, dry matter, and calcium. It is hoped that the present review will add further value to the scientific research on C. gratissimus and boost the increased interest in the study, development, and sustainable commercial exploitation of C. gratissimus as a medicine and as a health herbal tea. [ABSTRACT FROM AUTHOR]

Croton gratissimus is an important plant in Africa setup and across the globe for its ethnomedicinal uses in managing a wide range of diseases. Its phylogeny, pharmacological properties, ethnomedicinal uses, phytochemistry, and cytotoxicity have been highlighted in various articles and journals. This review article aims to give a comprehensively overviewed literature about Croton gratissimus genus. Authentic literature sources such as books, peer reviewed articles, journals, theses, Google Scholar, Science Direct, and any other validated internet source have been used to develop this review. Croton gratissimus is richly found across different climatic zones because of its ability to adapt to various climatic conditions. It is mainly found in rocky hills as a scrub that is about 12–15 m tall. Its leaves are glossy, green on the top, and silvery underneath. Some of the leaves may look brick red rusty. Croton gratissimus has been explored traditionally to manage a number of diseases among the human race since time immemorial. It has been used to treat different ailments ranging from respiratory tract infections, urinary tract infections, malaria, diabetes, hypertension, dermatological conditions, arthritis, gastrointestinal disorders, fever, sexually transmitted diseases, and infertility. Studies have shown that parts of this plant have antioxidative, antimicrobial, anticholinesterases inhibitory, antidiabetic, antihyperlipidemic, anticonvulsant, antiulcer, antihypertensive, antiproliferative, antiplasmodial, and anti-inflammatory activities. Terpenoids and flavonoids have shown to be the major classes of compounds in this plant. Its toxicity has not been well established; some studies have suggested that Croton gratissimus can cause hepatotoxicity and genotoxicity. More studies are needed to elucidate the compounds and their structures giving this plant a wide range of pharmacological activities, efficacy, safety, and toxicity levels, since the plant has greater ethnomedicinal uses. This would give a great indication of discovering new novelties that can give a breakthrough in drug discovery. [ABSTRACT FROM AUTHOR]

Plants are good sources of various bioactive substances and have significant importance for the discovery of new drugs. In this study, Croton macrostachyus plant roots from six different sites in the Central Gondar Zone, Ethiopia, were collected; and their phenolic and flavonoid contents, as well as antioxidant and antibacterial activities were investigated. Total phenolics and flavonoid contents of the root extracts were determined by the Folin–Ciocalteu and aluminum chloride methods, respectively. The antioxidant activity was determined by the DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging method. Moreover, the antibacterial activities were evaluated by disk diffusion method. Results revealed that total polyphenols and flavonoid contents were in the range of 802 ± 53–1557 ± 75 mg GAE/100 g and 342 ± 26–745 ± 32 mg CE/100 g, respectively. Root extracts of C. macrostachyus were found to have higher antioxidant activities ranging from 3.53 ± 0.38 to 6.38 ± 0.62 mg AAE/g sample. They also showed inhibition zones of 5.8, 6.2, 5.9 and 6.0 mm for Staphylococcus aurous, Staphylococcus pneumonia, Escherichia coli and Klebsiella pneumonia, and had equivalent potency with the reference Gentamicin antibiotic. Pearson correlation result indicated a strong relationship between total polyphenol contents and their respective antioxidant activities. This study articulates that the root extracts accumulated a substantial quantity of polyphenols and bears a considerable antioxidant activity. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Introduction: Human immunodeficiency virus (HIV) affects the body's defense mechanisms and leads to a number of opportunistic infections which later cause fatality as a result of an acquired immunodeficiency syndrome (AIDS). More than half a million individuals have lost their life in 2020 due to this disease. Antiretroviral drugs have played a great role in improving the quality of life of HIV infected individuals. The side effects of these drugs coupled with resistance of the virus to the various regimens, necessitates the search for potentially new and effective antiretroviral medication. The objective of this study is to evaluate anti-HIV activity of crude extracts of three Croton plants. Methods: As part of our effort in screening anti-HIV medications, we evaluated the cytotoxicity and anti-HIV activity of three Croton species used as herbal medicine in Africa. Crude extracts of Croton macrostachyus, Croton megalocarpus and Croton dichogamus were tested for their replication inhibition activity against laboratory adapted strains HIV-1IIIB in Human T-lymphocytic MT-4 cell line. Results: Based on our findings, the crude aerial part extract of C. dichogamus displayed the highest anti-HIV activity by inhibiting 73.74% of viral induced cytopathic effect (CPE) at IC50 value of 0.001 + 0.00 μg/mL giving a selectivity index (SI) of 3116.0. In addition, the crude leaf extract of C. megalocarpus showed higher anti-HIV activity by inhibiting 74.65% of CPE at IC50 value of 0.05 + 0.03 μg/mL giving an SI of 571.3. Conclusion: Out of five extracts from three Croton species screened for anti-HIV activity using human T-lymphocytic MT-4 cells, the leaf extract of Croton megalocarpus and aerial part extract of Croton dichogamus could be considered as promising extracts as they display high antiviral activity with low toxicity and high selectivity index values. To investigate the active constituents responsible for the anti-HIV activity, chemical identification of the active constituents is now in progress in our laboratory. Since there is no previously reported anti-HIV activity for these plants, there is a great need to isolate the compounds responsible for the noted activity. [ABSTRACT FROM AUTHOR]

Croton megalocarpus oil is a non-edible oil with potential to produce biodiesel in East Africa. Transesterification of the oil and methanol to produce fatty acid methyl ester (FAME) was studied using heterogeneous alkaline earth BaO, SrO, CaO, Nano CaO, Reoxidised CaO (CaO RO), MgO, Nano MgO, BeO catalysts; by conventional heating and by microwave irradiation. Catalysts were characterised by surface area, porosity, basic strength and basicity. FAME yield was obtained through Gas chromatography. Central Composite Design (CCD) was used to optimise process variables (reaction temp. /time, methanol-to-oil ratio, catalyst conc.) for the highest FAME yield through Response Surface Methodology (RSM) plots. Conventional heating gave a higher maximum yield, in the order: BaO(83%) > SrO(77%) > Nano CaO(74%) > CaO RO(42%) > CaO(32%) > Nano MgO(25%) > MgO(20%) > BeO(–). Yields were in order of the observed catalyst basicity, and independent of surface area. New catalyst CaO RO obtained from CaO showed higher activity. BeO showed no activity (<5%). Microwave irradiation gave slightly reduced maximum yields for BaO(78%), SrO(72%) and Nano CaO(62%). However, no such maxima were observed for other catalysts for the chosen reaction time. Microwave was found to be a superior heating mode due to highly reduced reaction times. [ABSTRACT FROM AUTHOR]

Eight experiments were carried out at Antoniades Research Branch, Ornamental Plants Research and Landscape Gardening Department Horticulture Research Institute, A.R.C., Alexandria, Egypt during the eight successive seasons, i.e. winter, spring, summer and fall during 2019 and 2020 to investigate the effect of indole butyric acid and seasonal changes on stem cuttings and rooting growth of Croton plants (Codiaeum variegatum L.). The cuttings were treated with four different concentrations of IBA at the rate of 1000, 2000, 3000 and 4000 ppm besides the control. Both 2000 and 3000 ppm IBA significantly improved rooting percentage%, survival % of cuttings and produced a significant increase in all vegetative root growth parameters (number of roots, fresh and dry weight of roots and root length). In addition, treated cuttings with 2000ppm also decreased the number of days to root. After 45 days, the rooting percentage gradually increased in comparison to the increase in IBA concentration to over 2000ppm, with results exceeding 88 percent in February. Furthermore, low-efficiency doses of growth regulators have led to fewer roots per cutting, potentially jeopardising the cuttings' survival under greenhouse conditions. In contrast, the greater temperature beneath the greenhouse and endogenous -auxin in the cuttings may be responsible for the rise in rooting percentage and improvement in root system metrics seen in the winter and spring after the autumn. [ABSTRACT FROM AUTHOR]

Background: Ayanin (3,7,4'-Tri-O-methylquercetin) and 3,7-Di-O-methylquercetin (DMQ) are the main active metabolites isolated by bioguided fractionation from Croton schiedeanus, species known popularly in Colombia as "almizclillo", which has been studied in experimental models in rats, exerting vasodilator and antihypertensive effects. Also, when the effect of these flavonoids was studied separately, important vasodilation was observed. Objective: To evaluate whether flavonoids from Croton schiedeanus have synergistic vasodilator properties when different combinations are used in isolated aorta rings. Methods: Cumulative concentrations of ayanin (10-8 M - 6x10-5 M or 0.01 μM - 60 μM) were assayed in the absence and presence of an increasing concentration of 3,7-Di-O-methylquercetin (DMQ) (10-8 - 3x10-5 M or 0.01-30 μM) in isolated rings from Wistar rats, pre-contracted with phenylephrine. The concentration-response curve with the maximal effect was compared with that obtained by Croton schiedeanus whole ethanolic extract (10-6 - 3x10-4 g/mL). Also, this combination was assayed in the presence of the nitric oxide synthetase inhibitor L-NAME (10-4 M) and the guanylate cyclase inhibitor methylene blue (10-4 M) to assess the role of the NO/cGMP pathway in this interaction. Results: Ayanin and DMQ display a dual interaction in vascular relaxant response: agonism at higher concentration ranges (10-6 - 3x10-5 M or 1-30 μM) and antagonism at lower concentration ranges (10-8 - 3x10-7 M or 0.01-0.3 μM). The efficacy at the highest concentration was greater than that obtained by the whole extract (Emax: 98.4% vs. 33.9%). This response was decreased but not reverted in the presence of L-NAME and methylene blue. Thus, the vasodilator effect of this combination does not depend entirely on the NO/cGMP cyclic pathway. Conclusion: The combined use of appropriate concentrations of these flavonoids could represent an advantage over Croton schiedeanus whole extract for vasodilator purposes. [ABSTRACT FROM AUTHOR]

Copyright of Biotropica is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study on two Croton species of Euphorbiaceae was carried out to differentiate their morphological, anatomical and phytochemical characteristics. The present study reveals their morphological, anatomical and phytochemical individualities. It also highlights its great value for future studies to disclose their potential medicinal values for human welfare. [ABSTRACT FROM AUTHOR]

Structurally unique halimanes EBC‐232 and EBC‐323, isolated from the Australian rainforest plant Croton insularis, proved considerably difficult to elucidate. The two diastereomers, which consist an unusual oxo‐6,7‐spiro ring system fused to a dihydrofuran, were solved by unification and consultation of five in silico NMR elucidation and prediction methods [i.e. ACDLabs, olefin strain energy (OSE), DP4, DU8+ and TD DFT CD]. Structure elucidation challenges of this nature are prime test case examples for empowering future AI learning in structure elucidation. [ABSTRACT FROM AUTHOR]

Croton menyharthii root bark is used to manage female reproductive ailments in Tana River County, Kenya. The plant treats dysmenorrhea, prevents abortion, stops post-partum hemorrhage and is also a contraceptive. Toxicological and phytochemical profile of the plant is still unknown. Preliminary phytochemical screening of Dichloromethane-Methanol and aqueous Croton menyharthii root bark extracts was carried out as per method used by Kisianan et al., 2019. Acute oral toxicity study was conducted using female rats by using OECD 423 guidelines whereas the sub-acute toxicity study was carried out using OECD 407 guidelines. General behavior, adverse effects and mortality were keenly observed throughout the experimental period. Food intake, water intake, body weight, organ weight, hematological and biochemical parameters were evaluated. Alkaloids, saponins, phenols, cardiac glycosides and tannins were present in both organic and aqueous extract. Both extracts had acute oral toxicity greater than 2000 mg/kg. In the sub-acute toxicity study, there was a significant dose-dependent decrease in the levels of total protein in rats treated with 200 (P<0.006), 400 (P<0.00) and 800 mg/kg (P< 0.00) aqueous extract relative to the control. None of the extracts caused a significant effect on haematological parameters. Long term administration of Croton menyharthii root bark extract is associated with significant alterations in renal physiology. Given the finding, we recommend the judicious use of the root bark extracts of Croton menyharthii particularly when long term use is being considered. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Plant Production is the property of Egyptian National Agricultural Library (ENAL) and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The study on two Croton species of Euphorbiaceae was carried out to differentiate their morphological, anatomical and phytochemical characteristics. The present study reveals their morphological, anatomical and phytochemical individualities. It also highlights its great value for future studies to disclose their potential medicinal values for human welfare. [ABSTRACT FROM AUTHOR]

The empirical use of plants for medicinal purposes is an ancient practice. The Croton genus specifically is frequently utilized by indigenous communities in South America to treat a variety of infections. In this work, the potency of the latex coming from the Croton gossypiifolius (Euphorbiaceae) tree as antimicrobial agent was studied. Also known as "Dragon's blood", it was tested over microorganisms associated to infections in humans. The bacteria utilized were Klebsiella pneumoniae, Escherichia coli, Staphylococcus aureus, Pseudomona aeruginosa and the fungi Aspergillus niger. The "Dragon's blood" was collected directly from the cortex of the trees by making V shaped cuts. It was then added to nutritious agar and saburoud plates, where the bacteria and fungi were grown separately for the optimum time and temperature of each species. An inhibition of the growth of S. aureus was observed. To quantify this inhibitory effect, S. aureus was cultivated in a Luria Bertani liquid medium adding different latex concentrations (0.6%, 1.25%, 1.9%, 2.5%, 3.3%) for 6 hours on each concentration. The growth was measured in Petri plates as colonyforming units per ml (CFU/ml). A dose dependent effect was observed. For 0.6% the mean growth was 900 CFU/ml, and the growth value decreased as the latex concentration increased until the smallest value of 10 CFU/ml was observed when the concentration was 3.0%. The latex did not cause any inhibition in the growth of the bacteria E. coli, K. pneumoniae y P. aeruginosa, nor the fungi A. niger but it did inhibit the growth of S. aureus and the effect was dose dependent. [ABSTRACT FROM AUTHOR]

Fertilizer management is an essential step in the production process, as it allows the plant to use its productive capacity to the fullest extent possible. Researchers have tested maximum nutrient use with reduced losses to the environment aiming to increase productivity with fewer environmental impacts. This study compared the effects of controlled-release fertilizers (CRFs) with water-soluble fertilizer (WSF) and clear water (control) on the growth and nutrient uptake of croton (Codiaeum variegatum L.) and nitrogen leaching. The experiment was conducted with three replications and six treatments: two rates (1.5 g and 3.0 g per liter of substrate) of two CRFs [Osmocote Plus (15% N, 3.93% P, and 9.96% K) and Basacote (15% N, 3.49% P, and 9.96% K)], WSF, and clean water as control. All CRFs were applied before planting and WSF was supplied as nutrient solution through automated moisture sensor activated irrigation system. Plant growth (number of leaves, leaf area, stem height, root volume, and shoot and root dry weights) and total nutrient contents in the leaf tissue were evaluated every 30 days. Electrical conductivity (EC), pH, nitrate, ammonium, and total nitrogen contents were measured in the leached solution. Indeed, results showed that CRFs at a low rate provided similar development and quality of croton plants compared with WSF. Plant growth indicators were similar until 90 days after transplanting (DAT). After that, at 150 DAT, the highest values to number of leaves and leaf area occurred with WSF and with the lowest CRF rate as compared with the other treatments and control. The highest root volume was found with the WSF, which resulted in larger roots compared with the other treatments. These results showed WSF can be replaced by CRFs at low rates on croton growth. Moreover, according to the visual scale, the best treatments were WSF and Basacote at the low rate, where plants were bright, with multicolored leaves with prominent orange shades. However, CRFs maintained pH and EC within the recommended range for the growth of croton and reduced the nitrogen leaching from the pots. [ABSTRACT FROM AUTHOR]

Lung cancer has been the most common cancer in the world for several decades, and it was also the most common cause of death from cancer. Despite the several advances in the last few years into treatment of lung cancer, the survival remains extremely low. There is an urgent need to discover viable leads that can be developed into new clinically therapeutic drugs with good treatment effects. The analysis of current reported literatures suggest that natural products possess strong inhibitory efficacy against lung cancer. The plants of Croton genus belonging to Euphorbiaceae family, are widely used as herbal medicine in the folk. Which are reported to have abilities to treat several cancer cell lines especially lung cancer, a successive study was carried out to identify selective anticancer agents from these plants specie. Herein we employed a network pharmacological approach to understand its multi-therapeutics potentiality in Croton genus against lung cancer. In total, the database of the compound was established based on the methods of network pharmacology prediction and the compound-disease target network was constructed. We believed that our study would provide important clues for finding novel drug inhibitors for lung cancer. [ABSTRACT FROM AUTHOR]

This study aimed to characterize the chemical diversity of essential oils of 37 Croton tetradenius plants grown in municipalities of the state of Sergipe, Brazil, as well as evaluate their antibacterial activities. Twenty-five compounds were identified in the essential oils of C. tetradenius, and low chemical variation was observed among the plants studied. Monoterpenes, such as α-pinene, α-terpinene, p-cymene, 1,8-cineole, trans-pinocarveol, camphor, pinocarvone, cis-ascaridole and trans-ascaridole were detected as major compounds. The Cluster Analysis revealed two different clusters. The antibacterial activity of the essential oils was tested against Bacillus cereus ATCC 4504, Staphylococcus aureus ATCC 8095, Listeria monocytogenes ATCC7644, Salmonella thyphimurium ATCC 14,028, and Escherichia coli ATCC 23,226. The minimum inhibitory concentration varied from 7.81 to 125 µL/mL for E. coli and the other species, respectively. The knowledge of the chemical diversity of the essential oil of native plants of C. tetradenius may encourage further studies on the potential use of these and other metabolites and help the adoption of strategies for the conservation of this medicinal species. [ABSTRACT FROM AUTHOR]

BACKGROUND Within its natural habitat, Croton ehrenbergii exhibits an innate defense mechanism that is not seen in other plants; it grows unharmed amidst predators and nature, while other species perish. In light of its capacity for defense, C. ehrenbergii was evaluated to better understand the scope of its phytotoxic and nematicide properties. To assess this, fractions obtained by bipartition of a hydro‐alcoholic extract, and l‐quebrachitol, the main constituent of C. ehrenbergii, were evaluated on Lactuca sativa (dicotyledon) and Lolium perenne (monocotyledon) seeds. Additionally, bipartition fractions and l‐quebrachitol were evaluated on a population of Meloidogyne incognita for their nematicide activity. RESULTS: From this phytochemical research, l‐quebrachitol (1), phenylalanine (2), trans‐4‐hydroxy‐N‐methylproline (3) and the flavonoids: kaempferol (4), tiliroside (5), nicotiflorine (6) and rutin (7) were identified by spectroscopic analysis. Both methanol and hexane fractions from aerial parts of the plant inhibited the germination and elongation of roots and stems in L. sativa, but not in Lolium perenne, showing that these fractions mostly inhibit the dicotyledon species used in this research. l‐Quebrachitol showed slightly higher seed germination inhibition for Lolium perenne in comparison with L. sativa. Three of the fractions evaluated showed nematicide activity against Meloidogyne incognita larvae (J2) at the 48 h benchmark, compared with carbofuran. l‐Quebrachitol shows higher mortality after 48 h exposure at a lower concentration than carbofuran. CONCLUSION: A variety of compounds were isolated from this research, some were common within the Croton genus (4–7), whereas others were not (1–3). This is the first phytochemical, phytotoxic and nematicide report on C. ehrenbergii. Methanol and hexane fractions from the aerial parts of C. ehrenbergii and l‐quebrachitol could be used as alternative natural herbicides, predominantly against dicotyledon weed seeds. All fractions had a good mortality percentage against J2 Meloidogyne incognita larvae. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

The aim of this research was to determine the phytoconstituents of the essential oil (EO) obtained from stems of Croton tricolor and to study its antifungal activity against several Candida species. The EO was extracted from C. tricolor stems by hydrodistillation with a Clevenger apparatus. This EO was characterized by four major components: epiglobulol, α-bisabolol, α-trans-bergamotol and β-caryophyllene. Microbiological assays were performed using the microdilution method in liquid medium to determine the minimum inhibitory concentration (MIC) for each Candida strain. EO concentrations from 1.0 to 1024 μg/mL inhibited the growth of all tested strains. Overall, the microbiological assays showed that C. tricolor EO has significant inhibitory activity against several Candida species. Thus, the C. tricolor stem EO is a promising natural product in the treatment of candidiasis. [ABSTRACT FROM AUTHOR]

Croton macrosepalus Sodré & M.J.Silva (sp. nov.), a new species found in the states of Bahia, Goiás, and Tocantins, in Brazil, is described and illustrated. Although it is morphologically similar to Croton spica, the novel species can be differentiated from it by having large glandular stipules, entire or sometimes serrulate leaf margins, petioles with 2-8 cylindrical nectary glands at the apex, ovate pistillate sepals, and a hat-shaped caruncle. The habitat, conservation status, phenology, and morphological relationships of the species are also discussed. Morphological data and molecular analyses using ITS and trnL-trnF support the placement of C. macrosepalus and C. spica in Croton sect. Geiseleria. A geographic distribution map, images, notes about the leaf anatomy of both species, and their phylogenetic relationships are provided. [ABSTRACT FROM AUTHOR]

Investigation of the Australian rainforest plant Croton insularis revealed seven new cis‐, two new trans‐cyclopropane casbanes, and the first trans‐cyclopropane seco‐casbane. The relative configuration of the cyclopropane moiety for all compounds (EBC‐182, 217, 218, 220, 343, 357, 358, 361, 365, 373; EBC=EcoBiotics Compound) was assigned using 13C NMR data. Comparison of the experimental electronic circular dichroism (ECD) spectra with the theoretical curves, calculated by TD‐DFT at the B3LYP/6‐31+G**//B3LYP/6‐31+G** level, in conjunction with NOE data afforded the absolute configuration. EBC‐180, 181 and 220 displayed potent activity against cervical carcinoma (HeLa cells). Ask for casbanes andCrotongiveth: The Australian rainforest plant Croton Insularis revealed new cis‐ and trans‐casbanes, along with the first trans‐seco‐casbane. Absolute configuration of all 10 casbanes was determined by ECD and one derivative displayed potent activity against HeLa cells. [ABSTRACT FROM AUTHOR]

A comprehensive study was conducted to evaluate the effects of ambient air pollution, land use, and soil properties on ground cover vegetation in the urban area of Varanasi city, situated in the Indo Gangetic Plain of India. Twelve leaf functional traits were assessed on eight most dominant herbaceous species belonging to four angiospermic families in three different land uses with varying air pollution loads and soil properties. Particulate matter (PM10 and TSP), gaseous pollutants (SO2, NO2, and O3), land uses (built-up area, shrub, and grass cover), and soil properties showed significant variability among the land uses. Air pollution was identified as the major stress factor which influenced leaf functional traits of ground cover vegetation followed by soil properties and land uses. Among the plants, Croton sparsiflorus was found to be the most responsive plants to all the factors. Plants responded differently under varying environmental factors as Euphorbia hirta was maximally influenced by air pollution, whereas the effect of land use was maximum in C. sparsiflorus. Influence of soil properties was highest in Digitaria ciliaris and Scoparia dulcis. All the environmental factors in combination maximally influenced non-enzymatic antioxidants (ascorbic acid and polyphenolics) followed by photosynthetic pigments among the different leaf functional traits. Among the environmental factors, NO2 and PM were identified as the most influencing factors regulating leaf functional traits followed by K level in soil and shrub cover. It can be concluded that responses of different leaf functional traits of ground cover vegetation varied with different environmental factors and responses were mostly species specific. [ABSTRACT FROM AUTHOR]

The plants of Croton genus, belonging to Euphorbiaceae family, are widely used as herbal medicine in the folk. Popular uses include treatment of cancer, HIV, fever, hypertension, inflammation, intestinal worms, malaria, pain, ulcers and weight-loss. Diterpenoids are very common in Croton, corresponding to clerodanes, tiglianes, kauranes, labdanes, cembranes, halimanes, trachylobanes, crotofolanes and sarcopetalanes. There are numerous studies indicated that the main active chemical constituents of Croton were diterpenoids. The plants of Croton genus have been closely watched by researchers due to its multiple activities and good development prospect. To obtain a more comprehensive perspective, it is necessary to publish a review focusing on the "diterpenoids from the genus Croton". This paper is presented as a review concentered on the diterpenoids different core frameworks and its pharmacological effects of Croton genus, which is useful to the further research and development of this plant. [ABSTRACT FROM AUTHOR]

Copyright of Brazilian Journal of Biology is the property of Instituto Internacional de Ecologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In the present study, the potential of aqueous whole plant extract of Croton sparsiflorus for biosynthesis of silver nanoparticles (AgNPs) was evaluated. The formation of AgNPs was confirmed by color changes and UV-Visible spectroscopy, which showed absorbance maxima peak at 417nm. The scanning electron microscope (SEM) analysis confirmed the particle size and x-ray diffraction (XRD) confirmed the crystalline character of AgNPs. AFM analysis also confirmed the surface morphology of synthesized AgNPs. Fourier transform infrared (FTIR) authorized the presence of alcoholic and phenolic groups played an important reduction role in the synthesis process. It shows the antibacterial efficiency against gram negative bacteria, Klebsiella pneumoniae and Salmonella paratyphi. From the results, it is suggested that green synthesized AgNPs could be used effective in future biomedical engineering. [ABSTRACT FROM AUTHOR]

Introduction: Croton macrostachyus (Broad-leaved Croton), belonging to the family Euphorbiaceae, has been used for the treatment of several human health problems including diabetes, malaria, and dysentery. An emerging antibiotic resistance among bacterial pathogens brings the most serious public health problems. Therefore, scientists are forced to explore new antibacterial agents from the medicinal plants. Objective: The present study aimed to analyze and evaluate the in vitro antibacterial activities of ethanol and methanolic extracts of C. macrostachyus stem barks against Staphylococcus aureus, Escherichia coli O157:H7, Salmonella typhi, and Shigella boydii. Materials and Methods: The stem barks of C. macrostachyus were extracted with ethanol and methanol and the antibacterial activities were evaluated against test bacteria by agar disk diffusion method, and the minimum inhibitory concentration and minimum bactericidal concentrations were determined using broth dilution method. Results: The results revealed that the ethanolic extracts of C. macrostachyus stem bark showed significant antibacterial activity against S. aureus at 150 mg/ml with the zone of inhibition of 18.00 ± 1.00 mm and 16.66 ± 0.57 mm, respectively. S. typhi was the most resistant bacterial pathogen to both crude extracts showing inhibition zones of 13.0 ± 1.0 mm and 14.66 ± 0.57 with methanolic and ethanolic extracts of C. macrostachyus at 150 mg/ml, respectively. Phytochemical screening of the methanolic and ethanolic extracts of C. macrostachyus indicated the presence of alkaloids, tannins, saponins, terpenoids, and steroids while flavonoids were found only in the ethanolic extract. Conclusion: From this study, it can be concluded that the ethanolic extract of the stem bark of C. macrostachyus served as a potential source of natural antibacterial agents, further purification of the active chemical compounds and testing them against a variety of pathogenic bacteria is suggested for the future for the development of therapeutic antibiotics. [ABSTRACT FROM AUTHOR]

The genus Croton belongs to the Euphorbiaceae family, which comprises approximately 1300 species. Many Croton species have been used as folk medicines. This review focuses on the chemical constituents from Croton species and their relevant biological activities, covering the period from 2006 to 2018. A total of 399 new compounds, including 339 diterpenoids, were reported. Diterpenoids are characteristic components of the Croton species. These isolated compounds exhibited a broad spectrum of bioactivities, including cytotoxic, anti-inflammatory, antifungal, acetylcholinesterase inhibitory, and neurite outgrowth-promoting properties. The present review provides a significant clue for further research of the chemical constituents from the Croton species as potential medicines. [ABSTRACT FROM AUTHOR]

Chemical investigation of the roots of Croton crassifolius led to the isolation of five pyran-2-one derivatives, including two brand new compounds ( 1 – 2 ), one new natural product ( 3 ) and two known compounds ( 4 – 5 ). Their structures and absolute configurations were established by spectroscopic analyses as well as comparison between the calculated optical rotation (OR) values with the experimental data. Interestingly, the new compound 1 showed an unusual negative chemical shift at H-11. It is well known that negative chemical shift values of 1 H NMR spectrum are extremely rare in natural products. Such a negative chemical shift of 1 H NMR spectrum was reproduced by density functional theory (DFT) calculations and explained by the shielding effect from the pyran-2-one ring over the hydrogen atom in the 3D conformations. Then, MTT assay was applied to evaluate the cytotoxicity of the isolated compounds ( 1 – 5 ) against two liver cancer cell lines (HepG2 and MHCC97H). The results suggested that compound 1 displayed the highest cytotoxicity with an IC 50 value of 9.8 μM against HepG2 cells. Moreover, there was no obvious cytotoxicity of compounds 1 – 5 on normal liver cell line LO2. Furthermore, the mechanism of apoptosis induction in compound 1 -treated HepG2 cells was investigated. The results showed that compound 1 could induce apoptosis via p53-mediated Ras/Raf/ERK suppression in HepG2 cells. [ABSTRACT FROM AUTHOR]

Pyrolysis of biodiesel at high temperatures may result in the formation of transient and stable free radicals immobilized on particulate emissions. Consequently, free radicals adsorbed on particulates are believed to be precursors for health-related illnesses such as cancer, cardiac arrest, and oxidative stress. This study explores the nature of free radicals and particulate emissions generated when Croton megalocarpus biodiesel is pyrolyzed at 600 °C in an inert environment of flowing nitrogen at a residence time of 0.5 s at 1 atm. The surface morphology of thermal emissions were imaged using a field emission gun scanning electron microscope (FEG SEM) while the radical characteristics were investigated using an electron paramagnetic resonance spectrometer (EPR). A g-value of 2.0024 associated with a narrow ∆Hp-p of 3.65 G was determined. The decay rate constant for the radicals was low (1.86 × 10−8 s−1) while the half-life was long ≈ 431 days. The observed EPR characterization of Croton megalocarpus thermal particulates revealed the existence of free radicals typical of those found in coal. The low g-value and low decay rate constant suggests that the free radicals in particulates are possibly carbon-centered. The mechanistic channel for the formation of croton char from model biodiesel component (9-dodecenoic acid, methyl ester) has been proposed in this study. [ABSTRACT FROM AUTHOR]