Acaricidal toxicity of 2'-hydroxy-4'-methylacetophenone isolated from Angelicae koreana roots and structure-activity relationships of its derivatives

The acaricidal activities of 2'-hydroxy-4'-methylacetophenone derived from Angelica koreana roots and its derivatives against Dermatophagoides farinae, Dermatophagoides pteronyssinus, and Tyrophagus putrescentiae were examined by vapor phase and contact toxicity bioassays. In the vapor phase toxicity bioassay, 2'-methylacetophenone (1.25 μg/cm(2)) was 8.0 times more toxic against D. farinae than benzyl benzoate (10.00 μg/cm(2)), followed by 3'-methylacetophenone (1.26 μg/cm(2)), 4'-methylacetophenone (1.29 μg/cm(2)), 2'-hydroxy-4'-methylacetophenone (1.75 μg/cm(2)), and 2'-hydroxy-5'-methylacetophenone (1.96 μg/cm(2)). In the contact toxicity bioassay, 3'-methylacetophenone (0.58 μg/cm(2)) was 17.24 times more effective against D. farinae than benzyl benzoate (7.52 μg/cm(2)), followed by 2'-methylacetophenone (0.64 μg/cm(2)), 2'-hydroxy-4'-methylacetophenone (0.76 μg/cm(2)), 4'-methylacetophenone (0.77 μg/cm(2)), and 2'-hydroxy-5'-methylacetophenone (1.16 μg/cm(2)). The acaricidal activities of 2'-hydroxy-4'-methylacetophenone derivatives against D. pteronyssinus and T. putrescentiae were similar to those against D. farinae. In terms of structure-activity relationships, acaricidal activity against the three mite species changed with the introduction of hydroxyl and methyl functional groups onto the acetophenone skeleton. Furthermore, some of 2'-hydroxy-4'-methylacetophenone derivatives could be useful for natural acaricides against three mite species.     

Acaricidal activity of Paeonia suffruticosa root bark-derived compounds against Dermatophagoides farinae and Dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

The acaricidal activities of materials derived from the root bark of Paeonia suffruticosa against adults of Dermatophagoides farinae and Dermatophagoides pteronyssinus were examined using direct contact and fumigation bioassays and compared with those of benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (deet), widely used acaricides. The active constituents of Paeonia root bark were identified as paeonol and benzoic acid by spectroscopic analyses. On the basis of 24-h LD50 values, the acaricidal activities of paeonol (7.82 microg/cm3) and benzoic acid (6.58 microg/cm3) against adult D. farinae were comparable to that of benzyl benzoate (7.72 microg/cm3) but higher than those of deet (36.34 microg/cm3) and dibutyl phthalate (33.92 microg/cm3). Against adult D. pteronyssinus, the acaricidal activities of paeonol (7.08 microg/cm3) and benzyl benzoate (7.22 microg/cm3) were comparable to that of benzyl benzoate (7.14 microg/cm3). Deet and dibutyl phthalate were less effective. In fumigation tests with both mite species, paeonol and benzoic acid were much more effective in closed containers than open ones, indicating that the effect of these compounds was largely a result of action in the vapor phase. Neither benzyl benzoate, deet, nor dibutyl phthalate exhibited fumigant toxicity. Paeonia root bark-derived materials, particularly paeonol and benzoic acid, merit further study as potential acaricides or lead compounds for the control of D. farinae and D. pteronyssinus.     

Acaricidal activity of clove bud oil compounds against Dermatophagoides farinae and Dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

The acaricidal activity of clove (Eugenia caryophyllata) bud oil-derived eugenol and its congeners (acetyleugenol, isoeugenol, and methyleugenol) against adults of Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using direct contact application and fumigation methods and compared with those of benzyl benzoate and N,N-diethyl-m-toluamide (DEET). Responses varied according to compound, dose, and mite species. On the basis of LD(50) values, the compound most toxic to D. farinae adults was methyleugenol (0.94 microg/cm(2)) followed by isoeugenol (5.17 microg/cm(2)), eugenol (5.47 microg/cm(2)), benzyl benzoate (9.22 microg/cm(2)), and acetyleugenol (14.16 microg/cm(2)). Very low activity was observed with DEET (37.59 microg/cm(2)). Against D. pteronyssinus adults, methyleugenol (0.67 microg/cm(2)) was much more effective than isoeugenol (1.55 microg/cm(2)), eugenol (3.71 microg/cm(2)), acetyleugenol (5.41 microg/cm(2)), and benzyl benzoate (6.59 microg/cm(2)). DEET (17.85 microg/cm(2)) was least toxic. These results indicate that the lipophilicity of the four phenylpropenes plays a crucial role in dust mite toxicity. The typical poisoning symptom of eugenol and its congeners was a similar death symptom of the forelegs extended forward together, leading to death without knockdown, whereas benzyl benzoate and DEET caused death following uncoordinated behavior. In a fumigation test with both mite species, all four phenylpropenes were much more effective in closed containers than in open ones, indicating that the mode of delivery of these compounds was largely due to action in the vapor phase. Eugenol and its congeners merit further study as potential house dust mite control agents or as lead compounds.     

Acaricidal activity of active constituent isolated in Chamaecyparis obtusa leaves against Dermatophagoides spp

Acaricidal activities of materials derived from Chamaecyparis obtusa leaves against Dermatophagoides farinae and Dermatophagoides pteronyssinus were examined using the dry film method and compared with that of commercial benzyl benzoate and N,N-diethyl-m-toluamide (DEET). The active constituent of the C. obtusa leaves was identified as beta-thujaplicin (C10H12(O2)) by spectroscopic analyses. Responses varied with dose. On the basis of a 24 h LC50 value, acaricidal activity against D. farinaewas more pronounced with beta-thujaplicin (72.2 mg/m2) than benzyl benzoate (89.9 mg/m2) and DEET (377 mg/m2). Acaricidal activity against D. pteronyssinus was more pronounced in beta-thujaplicin (62.1 mg/m2) than benzyl benzoate (72.4 mg/m2) and DEET (193 mg/m2). These results indicate that acaricidal activity of C. obtusa leaves likely results from by beta-thujaplicin. Beta-thujaplicin merits further study as potential house dust mite control agents or lead compounds.     

Acaricidal constituents isolated from Sinapis alba L. seeds and structure-activity relationships

Allyl isothiocyanate (AITC) and phenethyl isothiocyanate (PEITC) were isolated from Sinapis alba L. seeds and their effects against Dermatophagoides farinae and D. pteronyssinus were evaluated using the impregnated fabric disk method. The LD 50 values of their compounds and derivatives were then compared with those of a commercial acaricide, benzyl benzoate. On the basis of the LD 50 values against D. farinae, PEITC (0.21 microg/cm(2)) was the most toxic, followed by benzyl isothiocyanate (0.55 microg/cm(2)), phenyl isothiocyanate (1.09 microg/cm(2)), butyl isothiocyanate (1.24 microg/cm(2)), and AITC (1.36 microg/cm(2)); acetyl isothiocyanate (195.01 microg/cm(2)) was the least toxic. In addition, the acaricidal effects of AITC and PEITC against D. farinae were 7.4- and 47.8-fold greater than those of benzyl benzoate, respectively. Against D. pteronyssinus, PEITC was the most toxic (0.19 microg/cm(2)), followed by benzyl isothiocyanate (0.77 microg/cm(2)), phenyl isothiocyanate (1.37 microg/cm(2)), butyl isothiocyanate (1.50 microg/cm(2)), and AITC (2.88 microg/cm(2)); acetyl isothiocyanate (168.82 microg/cm(2)) was the least toxic. AITC and PEITC were 3.3- and 50.4-fold more active than benzyl benzoate against D. pteronyssinus, respectively. Taken together, these findings indicate that AITC, PEITC, and partial derivatives may be useful as preventive agents against dust mites. In addition, these results indicate that structure-activity is related to the aromatic structure, the number of carbon atoms, and the compounds hydrophobicity.     

Acaricidal activity of butylidenephthalide identified in Cnidium officinale rhizome against dermatophagoides farinae and dermatophagoides pteronyssinus (Acari: Pyroglyphidae)

The acaricidal activity of materials derived from the rhizome of Cnidium officinale against adults of Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using direct contact application and fumigation methods and compared with that of benzyl benzoate and N,N-diethyl-m-toluamide (DEET). The active constituent of the Cnidium rhizome was identified as butylidenephthalide by spectroscopic analyses. Responses varied with dose. On the basis of 24-h LD(50) values, the acaricidal activity of butylidenephthalide (6.77 microg/cm(2)) against D. farinae adults was comparable to that of benzyl benzoate (8.54 microg/cm(2)). Very low activity was observed with DEET (37.59 microg/cm(2)). Against D. pteronyssinus adults, butylidenephthalide (6.46 microg/cm(2)) and benzyl benzoate (6.68 microg/cm(2)) were equitoxic. DEET (17.98 microg/cm(2)) was relatively inactive. The typical poisoning symptom of butylidenephthalide was lethargy of treated mites, leading to death without knockdown, whereas benzyl benzoate and DEET caused death following uncoordinated behavior. In a fumigation test with both mite species, butylidenephthalide was much more effective in closed containers than open ones. Naturally occurring C. officinale rhizome-derived materials merit further study as potential house dust mite control agents or lead compounds.     

Acaricidal activity of constituents identified in Foeniculum vulgare fruit oil against Dermatophagoides spp. (Acari: Pyroglyphidae)

Acaricidal activities of components derived from Foeniculum vulgare fruit oil against Dermatophagoides farinae and Dermatophagoides pteronyssinus were examined using direct contact application and compared with that of the commercial repellent benzyl benzoate. The major biologically active constituent of Foeniculum fruit oil was characterized as (+)-fenchone by spectroscopic analyses. On the basis of LD(50) values, the compound most toxic to D. farinae was p-anisaldehyde (11.3 mg/m(2)) followed by (+)-fenchone (38.9 mg/m(2)), (-)-fenchone (41.8 mg/m(2)), benzyl benzoate (89.2 mg/m(2)), thymol (90.3 mg/m(2)), and estragol (413.3 mg/m(2)). Against D. pteronyssinus, p-anisaldehyde (10.1 mg/m(2)) was much more effective than benzyl benzoate (67.5 mg/m(2)), thymol (68.5 mg/m(2)), and estragol (389.9 mg/m(2)). These results indicate that the acaricidal activity of F. vulgare fruit oil likely results from (+)-fenchone and p-anisaldehyde. (+)-Fenchone was 20.3 times more abundant in the oil than p-anisaldehyde. (+)-Fenchone and p-anisaldehyde merit further study as potential house dust mite control agents or as lead compounds.     

Toxicity of atractylon and atractylenolide III Identified in Atractylodes ovata rhizome to Dermatophagoides farinae and Dermatophagoides pteronyssinus

The acaricidal activity of materials derived from rhizome of Atractylodes ovata (Atractylodes macrocephala) toward adult Dermatophagoides farinae and Dermatophagoides pteronyssinus was examined using fabric-circle residual contact and vapor-phase toxicity bioassays. Results were compared with those of the currently used acaricides: benzyl benzoate, dibutyl phthalate, and N,N-diethyl-m-toluamide (Deet). The active principles of A. ovata rhizome were identified as the sesquiterpenoids, atractylenolide III (1) and atractylon (2), by spectroscopic analysis. In fabric-circle residual contact bioassays with adult D. farinae, atractylenolide III (LD50, 103.3 mg/m2) and atractylon (136.2 mg/m2) were five and four times more toxic than Deet and 1.7- and 1.3-fold more active than dibutyl phthalate, respectively, based on 24 h LD50 values. These compounds were less toxic than benzyl benzoate (LD50, 45.8 mg/m2). Against adult D. pteronyssinus, atractylenolide III (LD50, 73.8 mg/m2) and atractylon (72.1 mg/m2) were eight times more active than Deet and 2.5-fold more toxic than dibutyl phthalate. These compounds were slightly less effective than benzyl benzoate (LD50, 46.0 mg/m2). In vapor-phase toxicity tests with both mite species, atractylenolide III and atractylon were effective in closed but not in open containers. These results indicate that the effect of these sesquiterpenoids was largely a result of action in the vapor phase. Naturally occurring atractylenolide III and atractylon merit further study as potential house dust mite control agents or leads because of their great activity as a fumigant.     

Acaricidal activity of pine essential oils and their main components against Tyrophagus putrescentiae,a stored food mite

Some essential oils obtained from the branches of four Pinus species (P. pinea L., P. halepensis Mill., P. pinaster Soil in Ait., and P. nigra Arnold) have been evaluated for their acaricidal activity by aerial diffusion against the stored food mite Tyrophagus putrescentiae (L.). All the essential oils showed a good efficacy, but P. pinea oil and its two constituents 1,8-cineole and limonene were the most effective compounds, showing 100% acaricidal activity at 8 microL; 1,8-cineole showed the same activity at 6 microL.     

Synthesis and antifungal activities of carabrol ester derivatives

Thirty-eight new ester derivatives of carabrol were designed, synthesized, and characterized by (1)H and (13)C NMR and HR-ESI-MS. Their antifungal activities against the fungal pathogen Colletotrichum lagenarium were evaluated using a spore germination assay. Of these 38 ester derivatives, 16 showed higher antifungal activity than that of carabrol and 7 showed higher antifungal activity than that of carabrone. It was found that the C-4 position of carabrol was a key position involving its antifungal activity, which showed the variation of 50% inhibition concentration (IC(50)) from 2.70 to 52.33 μg/mL. When substituted by the phenyl ring, the ester derivatives with electron-attracting groups showed higher activity than those with electron-donating ones. Two ester derivatives, carabryl 4-cynaobenzoate (II-17, IC(50) 2.70 μg/mL) and carabryl 4-isopropylbenzoate (II-27, IC(50) 2.82 μg/mL), showed only slightly lower antifungal activity than that of the positive control chlorothalonil (IC(50) 0.87 μg/mL) and have been identified as promising leads for development of new environmentally friendly fungicides.     

Carotenoid accumulation and characterization of cDNAs encoding phytoene synthase and phytoene desaturase in garlic (Allium sativum)

Phytoene synthase (PSY) and phytoene desaturase (PDS), which catalyze the first and second steps of the carotenoid biosynthetic pathway, respectively, are key enzymes for the accumulation of carotenoids in many plants. We isolated 2 partial cDNAs encoding PSY (AsPSY-1 and AsPSY-2) and a partial cDNA encoding PDS (AsPDS) from Allium sativum. They shared high sequence identity and conserved motifs with other orthologous genes. Quantitative real-time PCR analysis was used to determine the expression levels of AsPSY1, AsPSY2, and AsPDS in the bulbils, scapes, leaves, stems, bulbs, and roots of garlic. High-performance liquid chromatography demonstrated that carotenoids were not biosynthesized in the underground organs (roots and bulbs), but were very abundant in the photosynthetic organs (leaves) of A. sativum. A significantly higher amount of β-carotene (73.44 μg·g(-1)) was detected in the leaves of A. sativum than in the other organs.     

Synthesis, insecticidal, and acaricidal activities of novel 2-aryl-pyrrole derivatives containing ester groups

A series of novel 2-aryl-pyrrole derivatives containing ester groups were synthesized, and their structures were characterized by (1)H NMR spectroscopy and elemental analysis. The insecticidal activities against oriental armyworm, mosquito, diamondback moth, green rice leafhopper, and bean aphids and acaricidal activities against spider mite of these new compounds were evaluated. The results of bioassays indicated that some of these title compounds exhibited excellent insecticidal and acaricidal activities. The insecticidal activities against oriental armyworm of compounds IVa, IVd, IVe, IVf, IVg, IVi, IVk, and IVp were equal to commercialized Chlorfenapyr, and the insecticidal activities of most of compounds IVb, IVc, IVd, IVf, IVg, IVj, IVk, IVl, IVs, IVt, IVu, IVw, IVx, IVz, and Chlorfenapyr against mosquito at 0.10 mg kg (-1) were 100%, and the acaricidal activities of compounds IVd, IVe, IVf, IVg, IVh, IVi, and IVk were equal or superior to Chlorfenapyr. Especially, the results indicated that the acaricidal activity of [4-bromo-2-(4-chlorophenyl)-3-cyano-5-(trifluoromethyl)pyrrol-1-yl]methyl 3-methylbutanoate ( IVg) against spider mite was 2.65-fold as high as that of Chlorfenapyr from the value of LC 50.     

Repellent activity of essential oils and some of their individual constituents against Tribolium castaneum herbst

A tool for integrated pest management is the use of essential oils (EOs) and plant extracts. In this study, EOs from Tagetes lucida , Lepechinia betonicifolia , Lippia alba , Cananga odorata , and Rosmarinus officinalis , species grown in Colombia, were analyzed by gas chromatography-mass spectrometry. These oils as well as several of their constituents were tested for repellent activity against Tribolium castaneum , using the area preference method. The main components (>10%) found in EOs were methylchavicol, limonene/α-pinene, carvone/limonene, benzyl acetate/linalool/benzyl benzoate, and α-pinene, for T. lucida, L. betonicifolia, L. alba, C. odorata, and R. officinalis, respectively. All EOs were repellent, followed a dose-response relationship, and had bioactivity similar to or better than that of commercial compound IR3535. EOs from C. odorata and L. alba were the most active. Compounds from EOs, such benzyl benzoate, β-myrcene, and carvone, showed good repellent properties. In short, EOs from plants cultivated in Colombia are sources of repellents against T. castaneum.     

Design, synthesis, structure, and acaricidal/insecticidal activity of novel spirocyclic tetronic acid derivatives containing an oxalyl moiety

A series of novel spirocyclic tetronic acid derivatives containing an oxalyl moiety was designed and synthesized via the key intermediate 3-(2,4,6-trimethyl)-2-oxo-1-oxaspiro[4.4]-decyl-3-en-4-ol. The target compounds were identified by (1)H NMR and elemental analysis or high-resolution mass spectrum (HRMS). The results of bioassays indicated that most of the target compounds possessed excellent acaricidal activities against carmine spider mite larvae and eggs. Especially, diisopropylamino oxalyl compound 7g and piperidine oxalyl compound 7h were 1.4- and 2.3-fold as high as the activities of commercial Spiromesifen, respectively, against spider mite eggs. Moreover, most of the target compounds exhibited insecticidal activities against Lepidoptera pest. Interestingly, compounds containing alkylamino-substituted oxalyl moiety showed obvious selectivity between spider mite larvae and eggs because the activities against spider mite eggs of 7g and 7h were 25-fold those against spider mite larvae, whereas Spiromesifen had no significant differences in these activities. This meant that the introduction of an oxalyl moiety to spirocyclic tetronic acid might lead to novel biological activity characteristics.     

Synthesis of a combinatorial library of amides and its evaluation against the fall armyworm, Spodoptera frugiperda

The fall armyworm Spodoptera frugiperda is a polyphagous pest that causes important damage in different regions of America and mainly affects corn crops in both tropical and subtropical areas. Currently, control relies on both transgenic plants and/or chemical pesticides. In this work we describe the preparation of an indexed combinatorial library of amides and its toxic effect by contact against S. frugiperda . (E)-1-(1-Piperidinyl)-3-[4-(trifluoromethoxy)phenyl]-2-propen-1-one was the most active compound with an LD(50) = 0.793 μg mg(-1) of larva. This amide was also evaluated by ingestion and at the lowest concentration (1 mg kg(-1)) achieved 83.3% mortality.     

Determination of chlorophylls in Taraxacum formosanum by high-performance liquid chromatography-diode array detection-mass spectrometry and preparation by column chromatography

Taraxacum formosanum, a well-known Chinese herb shown to be protective against hepatic cancer as well as liver and lung damage, may be attributed to the presence of abundant carotenoids and chlorophylls. However, the variety and content of chlorophylls remain uncertain. The objectives of this study were to develop an high-performance liquid chromatography-diode array detection-mass spectrometry method for determination of chlorophylls in T. formosanum and preparation by column chromatography. An HyPURITY C18 column and a gradient mobile phase of water (A), methanol (B), acetonitrile (C), and acetone (D) could resolve 10 chlorophylls and an internal standard Fast Green FCF within 30 min with a flow rate at 1 mL/min and detection at 660 nm. Both chlorophylls a and a' were present in the largest amount (1389.6 μg/g), followed by chlorophylls b and b' (561.2 μg/g), pheophytins a and a' (31.7 μg/g), hydroxychlorophyll b (26.5 μg/g), hydroxychlorophylls a and a' (9.8 μg/g), and chlorophyllides a and a' (0.35 μg/g). A glass column containing 52 g of magnesium oxide-diatomaceous earth (1:3, w/w) could elute chlorophylls with 800 mL of acetone containing 50% ethanol at a flow rate of 10 mL/min. Some new chlorophyll derivatives including chlorophyllide b, pyropheophorbide b, hydroxypheophytin a, and hydroxypheophytin a' were generated during column chromatography but accompanied by a 63% loss in total chlorophylls. Thus, the possibility of chlorophyll fraction prepared from T. formosanum as a raw material for future production of functional food needs further investigation.     

NMR, HPLC-ESI-MS, and MALDI-TOF MS analysis of condensed tannins from Delonix regia (Bojer ex Hook.) Raf. and their bioactivities

The structures of the condensed tannins isolated from leaf, fruit, and stem bark of Delonix regia (Bojer ex Hook.) Raf. have been investigated with (13)C nuclear magnetic resonance ((13)C NMR) and high performance liquid chromatography electrospray ionization mass spectrometry (HPLC-ESI-MS) coupled with thiolysis and matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF MS) analyses. The results showed that these condensed tannins from D. regia possessed structural heterogeneity in monomer units and degree of polymerization. Propelargonidin (PP) and procyanidin (PC) were found in the leaf, fruit, and stem bark of D. regia, while prodelphinidin (PD) was found only in the leaves. The polymer chain lengths of condensed tannins from leaf and fruit organs were detected to be trimers to hexadecamers but from trimers to tridecamers for stem bark. B-type linkages were present in all these compounds. Condensed tannins from different parts of D. regia can be explored as tyrosinase inhibitors and food antioxidants because of their potent antityrosinase and antioxidant activities. The inhibitor concentration leading to 50% enzyme activity (IC(50)) was estimated to be 38 ± 1, 73 ± 2, and 54 ± 1.5 μg/mL for the condensed tannins of leaf, fruit, and stem bark. Condensed tannins extracted from stem bark exhibited the highest antioxidant activity; the DPPH scavenging activity (IC(50)) and the FRAP values were 90 ± 2 μg/mL and 5.42 ± 0.09 mmol AAE/g, respectively.     

Synthesis and biological activities of novel pyrazole oxime derivatives containing a 2-chloro-5-thiazolyl moiety

A series of novel pyrazole oxime derivatives containing a 2-chloro-5-thiazolyl moiety were synthesized. Their structures were confirmed by (1)H NMR, (13)C NMR, and elemental analysis. The preliminary bioassays showed that all of the title compounds had low acaricidal activity against Tetranychus cinnabarinus . However, most of them exhibited excellent insecticidal activity against Aphis medicagini at the dosage of 0.5 mg/mL, and some compounds still showed good insecticidal activity against A. medicagini even at the dosage of 0.2 mg/mL. Meanwhile, some title compounds displayed fungicidal and plant growth regulatory activities.     

Isolation, characterization and antifungal activity of major constituents of the Himalayan lichen Parmelia reticulata Tayl

Antifungal activity of hexane, ethyl acetate and methanol extracts of Parmelia reticulata was evaluated against soilborne pathogenic fungi, namely, Sclerotium rolfsii, Rhizoctonia solani, R. bataticola, Fusarium udum, Pythium aphanidermatum and P. debaryanum by poisoned food technique. Maximum antifungal activity was exhibited by hexane and ethyl acetate extracts against most of the test pathogens. Secondary metabolites, namely, (±)-isousnic acid, (±)-protolichesterinic acid, atranorin, evernyl, ethyl hematommate, ethyl orsellinate, methyl hematommate (3-formyl-2,4-dihydroxy-6-methylbenzoic acid methyl ester), 2-hydroxy-4-methoxy-3,6-dimethylbenzoic acid, 1-hydroxy-3,6-dimethoxy-8-methyl-xanthen-9-one, baeomycesic acid and salazinic acid, were isolated from the above extracts and identified by 1H NMR, 13C NMR and mass spectroscopic methods. When these metabolites were tested for antifungal activity against test pathogens, maximum antifungal activity was exhibited by (±)-protolichesterinic acid against R. solani (ED50=23.09 μg mL(-1)) and P. debaryanum (ED50=16.07 μg mL(-1)) and by atranorin against S. rolfsii (ED50=39.70 μg mL(-1)). The antifungal activity of protolichesterinic acid was found to be comparable to that of hexaconazole, a commercial fungicide.     

Effect of different vitamin D supplementations in poultry feed on vitamin D content of eggs and chicken meat

According to a new European Union regulation, vitamin D(3) can be partially or totally substituted with 25-hydroxyvitamin D(3) (25-OH-D(3)) in hens' feed. The purpose of this study was to clarify how this regulation has affected the vitamin D content of commercial eggs and chicken meat. Another aim was to investigate how effectively 25-OH-D(3) is transferred from the hens' diet to egg yolk by analyzing eggs from farms using known commercial feeds and by conducting an animal study. Vitamin D determinations were made by HPLC methods. The vitamin D(3) contents of two commercial egg yolk pools were 4.9 ± 0.14 and 4.0 ± 0.10 μg/100 g, and the 25-OH-D(3) contents were 1.3 ± 0.19 and 1.0 ± 0.07 μg/100 g. The chicken meat pools contained 0.2-0.3 μg of vitamin D(3)/100 g, whereas the content of 25-OH-D(3) was ≤0.2 μg/100 g. These results are comparable to earlier data. The animal and farm studies showed that 25-OH-D(3) was effectively transferred from the hens' diet to yolk. However, because the relative activity between 25-OH-D(3) and vitamin D(3) is unknown, it remains questionable whether the use of 25-OH-D(3) in hens' feed is beneficial to human vitamin D intake from eggs.