Efficacy of plant extracts against stored-products fungi

The activity of leaf extracts, fractions, and isolated compounds from Ptaeroxylon obliquum against nine phytopathogenic fungi and the nematode Meloidogyne incognita

Phytopathogenic fungi and nematodes cause great losses in economically important crops and food production especially in developing countries. To minimize the use of fungicides and nematicides, researchers have concentrated on the use of natural products for crop disease prevention or control. The aim of the study was to investigate the antifungal activity of Ptaeroxylon obliquum leaf extracts, fractions, and isolated compounds (obliquumol and a mixture of lupeol and β-amyrin) and nematocidal activity of fractions (hexane, chloroform and 30% water in methanol and the isolated compounds) on Meloidogyne incognita. Nine phytopathogenic fungi (Aspergillus niger, A. parasiticus, Colletotrichum gloeosporioides, Fusarium oxysporum, Penicillium digitatum, P. expansum, P. italicum, P. janthinellum, and Rhizoctonia solani) were used for testing and nematocidal activity was determined on motility of plant parasitic nematode Meloidogyne incognita race 2 juveniles. Serial microdilution test was utilized to determine the minimum inhibitory concentration (MIC) of each sample against the fungus. Motility tests was done on the second-stage juveniles (J2s) of M. incognita. The most susceptible phytopathogenic fungal species to the acetone crude leaf extracts were A. niger, C. gloeosporioides and P. digitatum with MIC of 80 μg/ml which is considered pharmacological significant. Rhizoctonia solani was the most susceptible fungus against obliquumol and, lupeol and β-amyrin mixture with MIC values of 8 μg/ml and 16 μg/ml respectively. Lupeol & β-amyrin mixture had good activity on juvenile motility at high concentrations used which was significantly high (p ≤ 0.05) after 24 h, further incubation resulted in temporary paralysis at lower concentrations. Fractions and obliquumol showed good activity after 48 h, stable paralysis was observed up to 72 h. The extracts and isolated compounds may be useful as fungicides if the in vitro results can be confirmed under field conditions at levels not toxic to beneficial soil organisms.

Bio-preservatives and essential oils as an alternative to chemical preservatives in the baking industry: a concurrent review

The use of chemical preservatives in the baking industry is a common practice to extend the shelf life of baked goods However, there is growing interest in natural alternatives due to worries about the security and potential health risks of these chemicals. The purpose of this concurrent review is to investigate the potential of using essential oils and bio-preservatives in place of chemical preservatives in the baking industry. With a focus on their efficiency in extending the shelf life of baked goods, the review includes a thorough analysis of the most recent research on the use of bio-preservatives and essential oils in food preservation. The findings suggest that bio-preservatives and essential oils can be effective in preserving baked goods and may offer a safer and more natural alternative to chemical preservatives. However, further research is needed to fully understand the potential of these natural alternatives and to optimize their use in the baking industry.

The phytochemical profiling, pharmacological activities, and safety of malva sylvestris: a review

Malva sylvestris is a plant commonly found in Europe, Asia, and Africa. The leaves and flowers of this plant have been used for centuries in traditional medicine to treat various ailments such as cough, cold, diarrhoea, and constipation. Google Scholar, PubMed, Scopus, and Web of Science were used to search for relevant material on the phytochemical profiling and pharmacologic activities of Malva sylvestris. The techniques used in phytochemical profiling and the pharmacologic activity of each compound were extracted from the included studies, including in vitro, in vivo, and clinical studies. The phytochemical analysis of Malva sylvestris revealed that the leaves and flowers are the most commonly used parts of the plant and contain various bioactive compounds such as flavonoids, mucilages, terpenoids, phenol derivatives, coumarins, sterols, tannins, saponins, and alkaloids. These phytochemicals are responsible for the many pharmacological activities of Malva sylvestris, such as anti-inflammatory, antimicrobial, hepatoprotective, laxative, antiproliferative and antioxidant properties. This review has presented an overview of the antinociceptive and anti-inflammatory activities and the cytotoxic effects of Malva sylvestris on different types of cancer cells. It has also summarised the work on developing copper oxide nanoparticles using Malva sylvestris leaf extract and its potential use in food and medicine. This review aims to highlight the traditional uses, phytochemistry, pharmacological activities, and safety of Malva sylvestris.

A Review on Health Benefits of Malva sylvestris L. Nutritional Compounds for Metabolites, Antioxidants, and Anti-Inflammatory, Anticancer, and Antimicrobial Applications

The utilization of medicinal plants and their derivatives in treating illnesses is more appropriately recognized as herbal remedy than traditional medicine. For centuries, medicinal herbs have been used for the treatment of diseases in many countries. Malva sylvestris L. is a kind of mallow derived from Malvaceae species and is recognized as common mallow. This amazing plant has antimicrobial, hepatoprotective, anti-inflammatory, and antioxidant properties and is considered as one of the most promising herbal medicinal species. This plant's traditional use in treating many diseases and preparing pharmaceutical compounds can show us how to know in depth the plant origin of drugs used to produce antibiotics and other therapeutic agents.

Effectiveness of essential oil extracted from pompia leaves against Penicillium digitatum

BACKGROUND

In recent years, interest in the use of natural compounds as possible substitutes for chemicals, to prevent microbial food spoilage has grown. The antimicrobial activity of the essential oils (EOs) is well known and nowadays there is renewed interest in their application as natural preservatives in postharvest management. The aims of this study were to characterize the EO extracted from pompia leaves and to evaluate its effectiveness for the control of the postharvest decay agent Penicillium digitatum, when applied as vapor contact in new airtight boxes, supplied with a heating system.

RESULTS

Fumigation was performed in vitro and on food using two concentrations of the EO, heated at controlled temperature. The headspace analysis revealed that the heating of the EO favored the evaporation of the volatile compounds, without altering their functionality. The treatments reduced the pathogen growth in vitro and rot on inoculated food by about 50%.

CONCLUSION

The chemical analysis of the vapor composition demonstrated that heating the oil did not alter the components and thus the antimicrobial effect of the oil. The treatment by vapor contact with the EO was effective in controlling the pathogen growth in vitro but, above all, it was successful in halving rot in vivo. Due to their bioactivity in the vapor phase, EOs could be delivered as fumigants during postharvest protection; however, the techniques commonly employed are not ideal for simulating real pre-treatment conditions. The new device allows real large-scale conditions to be reproduced. © 2020 Society of Chemical Industry.

Phytochemical analysis and wound healing studies on ethnomedicinally important plant Malva neglecta Wallr

ETHNOPHARMACOLOGICAL RELEVENCE

The use of herbal medicines is increasing in developed countries as alternative and/or supportive therapy to conventional health care medicines. Malva neglecta Wallr. (Family: Malvaceae) has been reported as wound healing remedy in traditional medicines, however no experimental data is available on its wound healing potentials. The aim of this study was to explore phytochemistry and validate wound healing potentials of the plant using animal models.

MATERIALS AND METHODS

M. neglecta crude methanolic extract (Mn.Cme) was chemically characterized using HPLC-DAD and GCMS analysis. Acute dermal toxicity was determined in albino rats following Organization of Economic Co-operation and Development (OECD) 402 established standards. Wound healing potentials were evaluated in rats using excision wound model. Wounds (177 mm²) were made by an excision on the skin of rats which were placed individually in cages. Mn.Cme was formulated in ointment form and was applied topically onto the wound area once daily for 14 days. The wound area was measured with translucent paper and thereafter estimated on a 1 mm² graph sheet every 3rd day until epithelialization and complete wound closure was recorded. Wound contraction was calculated as a percentage of the original wound size. Antioxidant potentials were also evaluated via FRAP, DPPH and H₂O₂ free radicals scavenging assays.

RESULTS

HPLC-DAD analysis revealed 25 phenolic compounds with higher amounts of hydrotyrosol (109.3 mg/g), coumaroylhexoside (97.4 mg/g), kaempferol-3-(p-coumaroyldiglucoside)-7-glucoside (37.2 mg/g), quercetin-3-O-rutinoside (31.5 mg/g) and epicatechin-3-O-(4-O-methyl)-gallate (31.3 mg/g). In GC-MS analysis, oleic acid (19.67%), taurine (17.60%), ethylene dimercaptan (14.67%), isoeugenol (14.61%), patchoulane (10.36%), methyl 12-methyltetradecanoate (8.47%) and isopropyl myristate (7.02%) were highly abundant compounds. No sign of toxicity was observed in the acute dermal toxicity test. Our test sample (Mn.Cme) exhibited considerable wound healing tendency at all doses (1 g, 1.5 g, 2 g per 10 g of ointment base) with reduced epithelialization period in a dose-related manner. Absolute healing was observed after application of 2 g of Mn.Cme ointment. Further, Mn.Cme exhibited considerable anti-radical potential in all assays.

CONCLUSION

It may be concluded that M. neglecta possess very potent secondary metabolites which are previously reported for wound healing potentials. The plant has considerable antioxidant and wound healing properties and thus warrant further studies to uncover the molecular mechanism its wound healing potentials.

Essential and Recovery Oils from Matricaria chamomilla Flowers as Environmentally Friendly Fungicides Against Four Fungi Isolated from Cultural Heritage Objects

Recovery oils, obtained from the hydro-distillation of the fresh flowers of Matricaria chamomilla, as well as essential oils, were studied for their environmental purposes in cultural heritage. These oils were assayed for their antifungal activity against the growth of four molds isolated from archaeological manuscripts (Aspergillus niger), museum gypsum board Antique (A. flavus), museum archaeological tissue (A. terreus), and museum organic materials (Fusarium culmorum) of cultural heritage objects. Oils were applied to inhibit the growth of fungi at amounts of 25, 50, 75 and, 100 µL/mL, and compared with negative controls (0 µL/mL) or positive controls (Sertaconazol 3g/L). Using GC/MS analysis, the main chemical compounds identified in the essential oil were (Z)-β-farnesene (27%), D-limonene (15.25%), and α-bisabolol oxide A (14.9%), while the compounds identified in the recovery oil were α-bisabolol oxide A (18.6%), d-limonene (8.82%), and α-bisabolol oxide B (7.13%). A low amount of chamazulene was observed in both essential and recovery oils, with amounts of 0.73% and 3.50%, respectively. Recovery oil, at a concentration of 75 and 100 µL/mL, showed fungal mycelial inhibition (FMI) percentage for the growth of A. niger, with values of 78% and 85%, respectively. At a concentration of 100 µL/mL, both oils showed 100% FMI of A. terreus. Oils showed weak activity against the growth of A. flavus. Essential oils at 100 µL/mL had good activity against the growth of F. culmorum, with FMI of 86.6%. The results suggest the potential use of essential and recovery oils from M. chamomilla fresh flowers as environmentally friendly bio-fungicides.

Inhibition of Fusarium culmorum, Penicillium chrysogenum and Rhizoctonia solani by n-hexane extracts of three plant species as a wood-treated oil fungicide

AIMS

Wood as a packing tool is used for packaging and transportation of fruits and vegetables for a time period varying from hours to days. During transportation, fruits and vegetables can be affected by moulds with significant postharvest problems. The present study describes the possibility of using wood-treated oil fungicide of n-hexane extracts from Eucalyptus camaldulensis (aerial parts), Vitex agenus-castus (leaves) and Matricaria chamomilla (flowers) against the infestation of Fusarium culmorum, Rhizoctonia solani and Penicillium chrysogenum.

METHODS AND RESULTS

Air-dried wood samples of Melia azedarach were prepared with the dimensions of 0·5 × 1 × 2 cm and treated with the oily extracts at the concentrations of 0, 1, 2 and 3%. Oils extracted with n-hexane from E. camaldulensis and V. agenus-castus showed promising antifungal activities against the isolated and molecularly identified three fungi F. culmorum, R. solani and P. chrysogenum, while M. chamomilla observed the lowest activity against the studied fungi. GC/MS analysis of oils reported that the major components in E. camaldulensis were β-fenchol (25·51%), Cyclobuta[1,2:3,4]dicyclooctene-1,7(2H,6bH)-dione,dodecahydro,(6αβ,6βα,12αα,12ββ)- (17·05), 1,8-cineole (eucalyptol) (12·01%) and sabinene (9·45%); in V. agenus-castus were eucalyptol (22·17%), (E)-β-caryophyllene (18·39%), and β-sitosterol (12·44%); while in M. chamomilla were bisabolol oxide A (27·87%), (Z)-β-farnesene (16·11%), D-limonene (14·18%) and chamazulene (11·27%).

CONCLUSIONS

The results suggest using n-hexane oily extracts from E. camaldulensis and V. agenus-castus as a biofungicide for wood protection.

SIGNIFICANCE AND IMPACT OF THE STUDY

This study highlights the importance of using bio-friendly fungicide agents to protect wood against most common moulds occurring during handling of food packaging.

Essential oils as natural preservatives for bakery products: Understanding the mechanisms of action, recent findings, and applications

Bakery products, as an important part of a healthy diet, are characterized by their limited shelf-life. Microbiological spoilage of these products not only affects the quality characteristics and result in the economic loss but also threatens consumer's health. Incorporation of chemical preservatives, as one of the most conventional preserving techniques, lost its popularity due to the increasing consumer's health awareness. Therefore, the bakery industry is seeking alternatives to harmful antimicrobial agents that can be accepted by health-conscious customers. In this regard, essential oils have been previously used as either a part of product ingredient or a part of the packaging system. Therefore, the antimicrobial aspect of essential oils and their ability in delaying the microbiological spoilage of bakery products have been reviewed. Several types of essential oils, including thyme, cinnamon, oregano, and lemongrass, can inhibit the growth of harmful microorganisms in bakery products, resulting in a product with extended shelf-life and enhanced safety. Research revealed that several bioactive compounds are involved in the antimicrobial activity of essential oils. However, some limitations, such as the possible negative effects of essential oils on sensory parameters, may limit their applications, especially in high concentrations. In this case, they can be used in combination with other preservation techniques such as using appropriate packaging materials. Further research regarding the commercial production of the bakery products formulated with essential oils is required in this area.

Molecular authentication of Anthemis deserti Boiss. (Asteraceae) based on ITS2 region of nrDNA gene sequence

The dried plant material of medicinally important Anthemis deserti Boiss. (family: Asteraceae) especially when it remains in the powdered form often look similar to Anthemis melampodina Del.; and therefore, difficult to distinguish, finally lead to chances of adulteration. The adulteration in medicinal plants effects on the efficacy of the drugs. The molecular authentication of herbal plant materials such as based on the internal transcribed spacer 2 (ITS2) sequences of nuclear ribosomal DNA (nrDNA) is considered as more reliable method compared to other the biochemical or histological methods. The present study aims to molecular authentication ofA. deserti based on molecular phylogenetic analyses of ITS2 gene sequence of nrDNA region. The ITS2 region of nrDNA of A. deserti were sequenced, and the molecular phylogenetic analyses were performed together with the GenBank sequences. The Maximum Parsimony tree revealed the close relationships of A. deserti with A. melampodina; however, the Neighbor-Joining and Maximum Likelihood tree clearly revealed that A. deserti is distinct from A. melampodina, which is also supported by the differences in nucleotides at five diffident positions (i.e. 22, 28, 87, 175 and 198) in the DNA sequence alignment.

Evidence Supports Tradition: The in Vitro Effects of Roman Chamomile on Smooth Muscles

The dried flowers of Chamaemelum nobile (L.) All. have been used in traditional medicine for different conditions related to the spasm of the gastrointestinal system. However, there have been no experimental studies to support the smooth muscle relaxant effect of this plant. The aim of our research was to assess the effects of the hydroethanolic extract of Roman chamomile, its fractions, four of its flavonoids (apigenin, luteolin, hispidulin, and eupafolin), and its essential oil on smooth muscles. The phytochemical compositions of the extract and its fractions were characterized and quantified by HPLC-DAD, the essential oil was characterized by GC and GC-MS. Neuronally mediated and smooth muscle effects were tested in isolated organ bath experiments on guinea pig, rat, and human smooth muscle preparations. The crude herbal extract induced an immediate, moderate, and transient contraction of guinea pig ileum via the activation of cholinergic neurons of the gut wall. Purinoceptor and serotonin receptor antagonists did not influence this effect. The more sustained relaxant effect of the extract, measured after pre-contraction of the preparations, was remarkable and was not affected by an adrenergic beta receptor antagonist. The smooth muscle-relaxant activity was found to be associated with the flavonoid content of the fractions. The essential oil showed only the relaxant effect, but no contracting activity. The smooth muscle-relaxant effect was also detected on rat gastrointestinal tissues, as well as on strip preparations of human small intestine. These results suggest that Roman chamomile extract has a direct and prolonged smooth muscle-relaxant effect on guinea pig ileum which is related to its flavonoid content. In some preparations, a transient stimulation of enteric cholinergic motoneurons was also detected. The essential oil also had a remarkable smooth muscle relaxant effect in this setting. Similar relaxant effects were also detected on other visceral preparations, including human jejunum. This is the first report on the activity of Roman chamomile on smooth muscles that may reassure the rationale of the traditional use of this plant in spasmodic gastrointestinal disorders.

Nectandra grandiflora By-Products Obtained by Alternative Extraction Methods as a Source of Phytochemicals with Antioxidant and Antifungal Properties

Nectandra grandiflora Nees (Lauraceae) is a Brazilian native tree recognized by its durable wood and the antioxidant compounds of its leaves. Taking into account that the forest industry offers the opportunity to recover active compounds from its residues and by-products, this study identifies and underlines the potential of natural products from Nectandra grandiflora that can add value to the forest exploitation. This study shows the effect of three different extraction methods: conventional (CE), ultrasound-assisted (UAE) and microwave-assisted (MAE) on Nectandra grandiflora leaf extracts (NGLE) chemical yields, phenolic and flavonoid composition, physical characteristics as well as antioxidant and antifungal properties. Results indicate that CE achieves the highest extraction phytochemical yield (22.16%), but with similar chemical composition to that obtained by UAE and MAE. Moreover, CE also provided a superior thermal stability of NGLE. The phenolic composition of NGLE was confirmed firstly, by colorimetric assays and infrared spectra and then by chromatographic analysis, in which quercetin-3-O-rhamnoside was detected as the major compound (57.75–65.14%). Furthermore, the antioxidant capacity of the NGLE was not altered by the extraction methods, finding a high radical inhibition in all NGLE (>80% at 2 mg/mL). Regarding the antifungal activity, there was observed that NGLE possess effective bioactive compounds, which inhibit the Aspergillus niger growth.

Evaluation of antioxidant and antifungal properties of the traditional plants against foodborne fungal pathogens

OBJECTIVE

To determine the antioxidant and antifungal activities of the essential oils from five aromatic herbs, including Thymus vulgaris, Chamaemelum nobile, Ziziphora clinopodioides, Zingiber officinale and Cuminum cyminum, against different Aspergillus and Penicillium species.

METHODS

The oils were subjected to screening for their possible antioxidant activity using the 2,2-diphenyl-1-picrylhydrazyl (DPPH) assay. The susceptibility test for the oils was carried out in terms of minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) using microdilution method.

RESULTS

The values of the essential oils in DPPH assay were as follows: T. vulgaris (450.11±5.23 μg/mL), Ch. nobile (602.73±4.8 μg/mL), Ziz. clinopodioides (1238.82±9.3 μg/mL), Cu. cyminum (1255.52±8.92 μg/mL) and Zin. officinale (5595.06±8.24 μg/mL). Our findings also indicated a strong activity against tested fungi for the oil of T. vulgaris (1250 μg/mL), followed by Cu. cyminum (1416 μg/mL), Zin. officinale (1833 μg/mL), Ziz. clinopodioides (2166 μg/mL) and Ch. nobile (3750 μg/mL). This study confirmed the excellent antifungal and antioxidant properties of the essential oils, especially T. vulgaris, against foodborne pathogenic fungi.

CONCLUSION

Owing to their strong protective features, these oils could be used in ethno-medicine as preventers of lipid peroxidation and cellular damage, and in food industries as preservers of foodstuffs against spoilage fungi. Also, they could be the candidates to develop new antibiotics and disinfectants to control infective agents.

Anatomy, Histochemistry, and Antifungal Activity of Anacardium humile (Anacardiaceae) Leaf

Leaves of Anacardium humile are used in Brazilian traditional medicine for the treatment of intestinal disturbances and skin lesions. This study aimed to define leaf diagnostic structural characters, to propose a new method of phytochemical analysis of secretions, prospect flavonoids and alkaloids, and to evaluate their inhibitory activity on Candida albicans. Common anatomical, phytochemical, and microbiological methods were used. Leaves of Anacardium occidentale were used as a reference for the structural analyses. The main structural characters were closed vascular system, absence of ducts at the medulla, bilateral mesophyll, absence of bundle sheath extension, and secretory idioblasts at the xylem. The ducts present schizogenous origin, and secreting activity is restricted to the initial phases of leaf blade expansion. The proposed new phytochemical method is practical and inexpensive and has potential for wide application. The abundance of tannins and flavonoids is related to medicinal use. A single peak in high-performance liquid chromatography indicated the presence of a pure substance not previously reported. The extract had a strong inhibitory effect on C. albicans. The obtained results confirm the potential of A. humile for the prospection of new bioactive compounds.

Malva sylvestris Inhibits Inflammatory Response in Oral Human Cells. An In Vitro Infection Model

The aim of this study was to investigate the in vitro anti-inflammatory activity of Malva sylvestris extract (MSE) and fractions in a co-culture model of cells infected by Aggregatibacter actinomycetemcomitans. In addition, we evaluated the phytochemical content in the extract and fractions of M. sylvestris and demonstrated that polyphenols were the most frequent group in all samples studied. An in vitro dual-chamber model to mimic the periodontal structure was developed using a monolayer of epithelial keratinocytes (OBA-9) and a subepithelial layer of fibroblasts (HGF-1). The invasive periodontopathogen A. actinomycetemcomitans (D7S-1) was applied to migrate through the cell layers and induce the synthesis of immune factors and cytokines in the host cells. In an attempt to analyze the antimicrobial properties of MSE and fractions, a susceptibility test was carried out. The extract (MIC 175 μg/mL, MBC 500μg/mL) and chloroform fraction (MIC 150 μg/mL, MBC 250 μg/mL) were found to have inhibitory activity. The extract and all fractions were assessed using a cytotoxicity test and results showed that concentrations under 100 μg/mL did not significantly reduce cell viability compared to the control group (p > 0.05, viability > 90%). In order to analyze the inflammatory response, transcriptional factors and cytokines were quantified in the supernatant released from the cells. The chloroform fraction was the most effective in reducing the bacterial colonization (p< 0.05) and controlling inflammatory mediators, and promoted the down-regulation of genes including IL-1beta, IL-6, IL-10, CD14, PTGS, MMP-1 and FOS as well as the reduction of the IL-1beta, IL-6, IL-8 and GM-CSF protein levels (p< 0.05). Malva sylvestris and its chloroform fraction minimized the A. actinomycetemcomitans infection and inflammation processes in oral human cells by a putative pathway that involves important cytokines and receptors. Therefore, this natural product may be considered as a successful dual anti-inflammatory-antimicrobial candidate.

Effects of Malva sylvestris and Its Isolated Polysaccharide on Experimental Ulcerative Colitis in Rats

Malva sylvestris is an edible plant that is consumed as a herbal supplement for its antiulcer and colon cleansing properties in traditional Persian medicine. This study was designed to evaluate its effects on ulcerative colitis, which is a chronic gastrointestinal inflammation. Colitis was induced by rectal instillation of acetic acid solution. Rats in different groups received aqueous, n-hexane, or ethanolic fractions of the plant before induction of colitis. Isolated polysaccharide of plant was also tested in 2 groups before and after induction of colitis. Macroscopic and microscopic evaluation of colitis showed that the aqueous fraction was very effective in preventing the inflammation and efficacy was lower for ethanolic and n-hexane fractions. Polysaccharide was effective in reducing signs of inflammation, especially as pretreatment. These beneficial effects provide evidences that this plant can be suggested for patients with this disease to improve their health condition or to reduce adverse effects of their medication.

Application of plant derived compounds to control fungal spoilage and mycotoxin production in foods

Food decay by spoilage fungi causes considerable economic losses and constitutes a health risk for consumers due to the potential for fungi to produce mycotoxins. The indiscriminate use of synthetic antifungals has led to the development of resistant strains which has necessitated utilization of higher concentrations, with the consequent increase in toxic residues in food products. Numerous studies have demonstrated that plant extracts contain diverse bioactive components that can control mould growth. The metabolites produced by plants are a promising alternative because plants generate a wide variety of compounds, either as part of their development or in response to stress or pathogen attack. The aim of this article is to summarize the results from the literature on in vitro and in vivo experiments regarding the effects of plant-derived products for controlling fungal growth. Data from research work on the mode of action of these metabolites inside the fungal cell and the influence of abiotic external factors such as pH and temperature are also covered in the present review. Furthermore, an analysis on how the stress factor derived from the presence of plant extracts and essential oils affects secondary metabolism of the fungus, specifically mycotoxin synthesis, is developed. Finally, the effectiveness of using plant-derived compounds in combination with other natural antimicrobials and its application in food using novel technologies is discussed.

Fusarium culmorum: causal agent of foot and root rot and head blight on wheat

Fusarium culmorum is a ubiquitous soil-borne fungus able to cause foot and root rot and Fusarium head blight on different small-grain cereals, in particular wheat and barley. It causes significant yield and quality losses and results in contamination of the grain with mycotoxins. This review summarizes recent research activities related to F. culmorum, including studies into its population diversity, mycotoxin biosynthesis, mechanisms of pathogenesis and resistance, the development of diagnostic tools and preliminary genome sequence surveys. We also propose potential research areas that may expand our basic understanding of the wheat-F. culmorum interaction and assist in the management of the disease caused by this pathogen.

TAXONOMY

Fusarium culmorum (W.G. Smith) Sacc. Kingdom Fungi; Phylum Ascomycota; Subphylum Pezizomycotina; Class Sordariomycetes; Subclass Hypocreomycetidae; Order Hypocreales; Family Nectriaceae; Genus Fusarium.

DISEASE SYMPTOMS

Foot and root rot (also known as Fusarium crown rot): seedling blight with death of the plant before or after emergence; brown discoloration on roots and coleoptiles of the infected seedlings; brown discoloration on subcrown internodes and on the first two/three internodes of the main stem; tiller abortion; formation of whiteheads with shrivelled white grains; Fusarium head blight: prematurely bleached spikelets or blighting of the entire head, which remains empty or contains shrunken dark kernels. IDENTIFICATION AND DETECTION: Morphological identification is based on the shape of the macroconidia formed on sporodochia on carnation leaf agar. The conidiophores are branched monophialides, short and wide. The macroconidia are relatively short and stout with an apical cell blunt or slightly papillate; the basal cell is foot-shaped or just notched. Macroconidia are thick-walled and curved, usually 3-5 septate, and mostly measuring 30-50 × 5.0-7.5 μm. Microconidia are absent. Oval to globose chlamydospores are formed, intercalary in the hyphae, solitary, in chains or in clumps; they are also formed from macroconidia. The colony grows very rapidly (1.6-2.2 cm/day) on potato dextrose agar (PDA) at the optimum temperature of 25 °C. The mycelium on PDA is floccose, whitish, light yellow or red. The pigment on the reverse plate on PDA varies from greyish-rose, carmine red or burgundy. A wide array of polymerase chain reaction (PCR) and real-time PCR tools, as well as complementary methods, which are summarised in the first two tables, have been developed for the detection and/or quantification of F. culmorum in culture and in naturally infected plant tissue.

HOST RANGE

Fusarium culmorum has a wide range of host plants, mainly cereals, such as wheat, barley, oats, rye, corn, sorghum and various grasses. In addition, it has been isolated from sugar beet, flax, carnation, bean, pea, asparagus, red clover, hop, leeks, Norway spruce, strawberry and potato tuber. Fusarium culmorum has also been associated with dermatitis on marram grass planters in the Netherlands, although its role as a causal agent of skin lesions appears questionable. It is also isolated as a symbiont able to confer resistance to abiotic stress, and has been proposed as a potential biocontrol agent to control the aquatic weed Hydrilla spp.

USEFUL WEBSITES

http://isolate.fusariumdb.org/; http://sppadbase.ipp.cnr.it/; http://www.broad.mit.edu/annotation/genome/fusarium_group/MultiHome.html; http://www.fgsc.net/Fusarium/fushome.htm; http://plantpath.psu.edu/facilities/fusarium-research-center; http://www.phi-base.org/; http://www.uniprot.org/; http://www.cabi.org/; http://www.indexfungorum.org/

Ethnobotanical and scientific aspects of Malva sylvestris L.: a millennial herbal medicine

OBJECTIVES

Malva sylvestris L., known as common mallow, is native to Europe, North Africa and Asia. In the Mediterranean region, this species has a long history of use as food, and due to its therapeutic relevance, some parts of this plant have been employed in traditional and ethnoveterinary medicines. The leaves in particular have been reported to have potent anti-inflammatory, antioxidant, anti-complementary, anticancer and skin tissue integrity activity. Additionally, an anti-ulcerogenic effect was recently proven, demonstrating that the aqueous extract was more effective than cimetidine, a potent medicine used to treat gastric ulcers. Due to its wide use and medicinal importance, many studies have been conducted; however, the information in the literature is very extensive and disseminated, making it difficult to use.

KEY FINDINGS

A complete review involving the ethnobotanical and scientific aspects of M. sylvestris has been made. The research has provided evidence that M. sylvestris has potential use as a medicinal plant and has highlighted a need for more studies involving clinical and toxicological aspects of its use.

SUMMARY

This review can contribute to the field with its historical context, and by describing the progress made, new ideas for researchers can arise.