Three new quinolizidine alkaloids from the roots of Sophora tonkinensis.

Three new quinolizidine alkaloids (1 - 3), including one new naturally isoflavone and cytisine polymer (3), along with 6 known ones were isolated from the ethanol extract of Sophora tonkinensis Gagnep. Their structures were elucidated by comprehensive spectroscopic data analysis (IR, UV, HRESIMS, 1D and 2D NMR), combined with ECD calculations. The antifungal activity against Phytophythora capsica, Botrytis cinerea, Gibberella zeae, and Alternaria alternata of the compounds was evaluated in a mycelial inhibition assay. Biological tests indicated that compound 3 exhibited strong antifungal activity against P. capsica with EC50 values of 17.7 µg/ml.

Quantitation of Lupinus spp. Quinolizidine Alkaloids by qNMR and Accelerated Debittering with a Resin-Based Protocol.

Quinolizidine alkaloids (QAs) are toxic secondary metabolites of the Lupinus species, the presence of which limits the expansion of lupin beans consumption, despite their high protein content. Evaluation of the level of alkaloids in edible Lupinus species is crucial from a food safety point of view. However, quantitation of QAs is complicated by the fact that not all important alkaloids used for quantitation are commercially available. In this context, we developed a method for the simultaneous quantitation of eight major lupin alkaloids using quantitative NMR spectroscopy (qNMR). Quantitation and analysis were performed in 15 different seed extracts of 11 Lupinus spp. some of which belonged to the same species, with different geographical origins and time of harvest, as well as in all aerial parts of L. pilosus. The mature seeds of L. pilosus were found to be a uniquely rich source of multiflorine. Additionally, we developed a protocol using adsorption or ionic resins for easy, fast, and efficient debittering of the lupine seeds. The protocol was applied to L. albus, leading to a decrease of the time required for alkaloids removal as well as water consumption and to a method for QA isolation from the debittering wastewater.

A pan-genome and chromosome-length reference genome of narrow-leafed lupin (Lupinus angustifolius) reveals genomic diversity and insights into key industry and biological traits.

Narrow-leafed lupin (NLL; Lupinus angustifolius) is a key rotational crop for sustainable farming systems, whose grain is high in protein content. It is a gluten-free, non-genetically modified, alternative protein source to soybean (Glycine max) and as such has gained interest as a human food ingredient. Here, we present a chromosome-length reference genome for the species and a pan-genome assembly comprising 55 NLL lines, including Australian and European cultivars, breeding lines and wild accessions. We present the core and variable genes for the species and report on the absence of essential mycorrhizal associated genes. The genome and pan-genomes of NLL and its close relative white lupin (Lupinus albus) are compared. Furthermore, we provide additional evidence supporting LaRAP2-7 as the key alkaloid regulatory gene for NLL and demonstrate the NLL genome is underrepresented in classical NLR disease resistance genes compared to other sequenced legume species. The NLL genomic resources generated here coupled with previously generated RNA sequencing datasets provide new opportunities to fast-track lupin crop improvement.

Quinolizidine alkaloids from Sophora alopecuroides with anti-inflammatory and anti-tumor properties.

Forty-three quinolizidine alkaloids (1-43), including twelve new matrine-type ones, sophalodes A-L (1-7, 17, 19 and 28-30), were isolated from the seeds of Sophora alopecuroides. Structurally, compounds 1-4 were the first examples of C-11 oxidized matrine-type alkaloids from Sophora plants. The structures and absolute configurations of new compounds were elucidated by extensive spectroscopic techniques, X-ray diffraction analysis, and quantum chemical calculation. In addition, the NMR data and absolute configuration of compound 18 was reported for the first time. All the isolates were evaluated for their inhibition on nitric oxide production induced by lipopolysaccharide in RAW 264.7 macrophages, among them, compounds 29, 38 and 42 exhibited the most significant activity with IC50 values of 29.19, 25.86 and 33.30 µM, respectively. Further research about new compound 29 showed that it also suppressed the protein levels of iNOS and COX-2, which revealed its anti-inflammatory potential. Moreover, additional research showed that compound 16 exhibited marginal cytotoxicity against HeLa cell lines, with an IC50 value of 24.27 µM.

Antimalarial alkaloid from Hypoestes forskaolii.

Following on from previous studies, we brought further our quest for anti-malarial agents isolated from plants grown in the Saudi Arabian Peninsula. Methanolic extracts were prepared from eighteen Saudi plants and then tested in vitro to assess their anti-malarial effects on Plasmodium falciparum K1, (a chloroquine-resistant strain) as well as their cytotoxicity on MRC5 (human diploid embryonic lung cell line) cells. Moderate anti-malarial activity was observed in extracts prepared from Hypoestes forskaolii (Vahl) R. Br. (IC50 value of 5.5 µg/ml) and Rhus retinorrhaea (IC50: 7.71 µg/ml). The remaining sixteen plant extracts appeared to be inactive (IC50 > 12.5 µg/ml). A novel phenanthro-quinolizidine alkaloid, 15ß-hydroxycryptopleurine-N-oxide, was isolated from H. forskaolii using bio-guided fractionation procedures. Chloroquine-resistant (K1) and chloroquine-sensitive (FCR3) strains of P. falciparum appeared very sensitive to the anti-malarial activity of 15ß-hydroxycryptopleurine-N-oxide, giving IC50 of 6.11 and 5.13 nM respectively. It showed cytotoxicity against MRC5 "IC50 of 24.45 nM" with selectivity indices of 4.0 and 4.76 against K1 and FCR3 strains, respectively. It is our understanding that this is the first account on phenanthro-quinolizidine alkaloids anti-malarial activity on a chloroquine-resistant P. falciparum strain.

Effects of two debittering processes on the alkaloid content and quality characteristics of lupin (Lupinus mutabilis Sweet).

BACKGROUND: The presence of quinolizidine alkaloids (QAs) in the species Lupinus mutabilis Sweet limits the expansion of its consumption and use, despite its high protein content. The objective of this research was therefore to determine the effect of two thermal treatments, aqueous (ATT) and saline (STT), on the QAs and total protein content, as well as on the texture (fracturability and hardness), visual perception attributes - hue (H*), luminosity (L*) and chromatism (C*) - and grain size in three lupin varieties (INIAP-450, INIAP-451, and Criollo). The water consumption required by each treatment was also measured. RESULTS: The debittering process with ATT helped to concentrate the total nitrogen by 560 g kg-1 and decreased the grain hardness to 2037 gf (grams of force) in the Criollo variety, while the chromatic parameters H* and C* increased in the three varieties. The STT treatment was more efficient than the ATT treatment in terms of the time required and the volume of water used to reduce the QAs to safe levels for consumption (2.5-3.5 g kg-1 ). The size of the grain increased to four times its original size; the luminosity L* decreased during cooking to a value of 41.49 in the Criollo variety and then increased to 57.42 during grain washing. CONCLUSIONS: The STT treatment is advisable for lupin debittering, although the extent of the effect was dependent on the variety. © 2020 Society of Chemical Industry.

Quinolizidine alkaloids are transported to seeds of bitter narrow-leafed lupin.

Narrow-leafed lupin (NLL, Lupinus angustifolius) is a promising legume crop that produces seeds with very high protein content. However, NLL accumulates toxic quinolizidine alkaloids (QAs) in most of its tissues, including the seeds. To determine the level of in situ biosynthesis in the seeds, we compared the accumulation of QAs with the expression of the biosynthetic gene lysine decarboxylase (LDC) in developing seeds and pods of a bitter (high-QA) variety of NLL. While QAs accumulated steadily in seeds until the drying phase, LDC expression was comparatively very low throughout seed development. In contrast, both QA accumulation and LDC expression peaked early in pods and decreased subsequently, reaching background levels at the onset of drying. We complemented these studies with MS imaging, which revealed the distribution patterns of individual QAs in cross-sections of pods and seeds. Finally, we show that a paternal bitter genotype does not influence the QA levels of F1 seeds grown on a maternal, low-QA genotype. We conclude that the accumulation of QAs in seeds of bitter NLL is mostly, if not exclusively, transported from other tissues. These results open the possibility of using transport engineering to generate herbivore-resistant bitter NLL varieties that produce QA-free seeds.

Quinolizidine and Pyrrolizidine Alkaloid Chemical Ecology - a Mini-Review on Their Similarities and Differences.

This mini-review summarizes over 40 years of research on quinolizidine (QAs) and pyrrolizidine alkaloids (PAs). Emphasis is on the chemical ecology of both groups of alkaloids, which serve as general defense compounds against herbivores for the plants producing them. For QAs and PAs, a number of insects (aphids, moths, beetles) have acquired tolerance. These specialists store the alkaloids and use them as defense chemicals against predators. In some PA sequestering moths, the adaptation is even more intricate and advanced. PAs can function as a morphogen to induce the formation of male coremata, inflatable organs that dissipate pheromones. In these insects, PAs are additionally used as a precursor for male pheromones. Female moths utilize their own PAs and those obtained from males via the spermatophore as nuptial gift, to transfer them to the eggs that thus become chemically protected. Novel genomic technologies will allow deeper insights in the molecular evolution of these two classes of alkaloids in plant-insect interactions.

Five New Alkaloids from the Roots of Sophora flavescens.

Five new quinolizidine alkaloids, including three sparteine-type alkaloids (1 - 3) and two cytisine-type alkaloids (4 and 5), along with four known ones, were isolated from the roots of Sophora flavescens. Their structures were determined by extensive spectroscopic techniques including IR, UV, NMR, and HR-ESI-MS. All the compounds were evaluated for their antibacterial activities against Staphylococcus aureus and Escherichia coli.

Transcript profiling of a bitter variety of narrow-leafed lupin to discover alkaloid biosynthetic genes.

Lupins (Lupinus spp.) are nitrogen-fixing legumes that accumulate toxic alkaloids in their protein-rich beans. These anti-nutritional compounds belong to the family of quinolizidine alkaloids (QAs), which are of interest to the pharmaceutical and chemical industries. To unleash the potential of lupins as protein crops and as sources of QAs, a thorough understanding of the QA pathway is needed. However, only the first enzyme in the pathway, lysine decarboxylase (LDC), is known. Here, we report the transcriptome of a high-QA variety of narrow-leafed lupin (L. angustifolius), obtained using eight different tissues and two different sequencing technologies. In addition, we present a list of 33 genes that are closely co-expressed with LDC and that represent strong candidates for involvement in lupin alkaloid biosynthesis. One of these genes encodes a copper amine oxidase able to convert the product of LDC, cadaverine, into 1-piperideine, as shown by heterologous expression and enzyme assays. Kinetic analysis revealed a low KM value for cadaverine, supporting a role as the second enzyme in the QA pathway. Our transcriptomic data set represents a crucial step towards the discovery of enzymes, transporters, and regulators involved in lupin alkaloid biosynthesis.

[Bioactive quinolizidine alkaloids from Sophora tonkinensis].

Twelve quinolizidine alkaloids were isolated from Sophora tonkinensis by means of silica gel, preparative MPLC, and preparative HPLC. On analysis of NMR spectroscopic data, their structures were established as 3-(4-hydroxyphenyl)-4-(3-methoxy-4-hydroxyphenyl)-3,4-dehydroquinolizidine(1), lanatine A(2), cermizines C(3), senepodines G(4), senepodines H(5), jussiaeiines A(6), jussiaeiines B(7),(+)-5α-hydroxyoxysophocarpine(8),(-)-12ß-hydroxyoxysophocarpine(9),(-)-clathrotropine(10),(-)-cytisine(11), and (-)-N-methylcytisine(12), respectively. Compounds 1-7 were first isolated from Sophora L. plant. In the in vitro assays,the isolated compounds 1, 3, 6-10 exhibited potent activity against CVB3 with IC50 of 6.40, 3.25, 4.66, 3.21, 0.12, 0.23 and 1.60, and with selective index values(SI=TC50/IC50)of 12.0, 5.6, 13.0, 15.1, 50.1, 26.2, and 23.6, respectively. Compounds 1, 3, and 7 exhibited activity against staphylococcus aureus(ATCC 29213)with MICvalues of 8.0, 3.5, 6.0 g•L⁻¹, respectively. Compounds 1, 3, 7, and 12 exhibited activity against staphylococcus aureus(ATCC 33591)with MIC values of 18.0, 7.5, 8.0, 12.0 g•L⁻¹, respectively. Compounds 2, 6, 7 exhibited activity against Escherichia coli(ATCC 25922) with MIC values of 1.0, 3.2, 0.8 g•L⁻¹.

Filling in the gaps of the papilionoid legume phylogeny: the enigmatic Amazonian genus Petaladenium is a new branch of the early-diverging Amburaneae clade.

Recent deep-level phylogenies of the basal papilionoid legumes (Leguminosae, Papilionoideae) have resolved many clades, yet left the phylogenetic placement of several genera unassessed. The phylogenetically enigmatic Amazonian monospecific genus Petaladenium had been believed to be close to the genera of the Genistoid Ormosieae clade. In this paper we provide the first DNA phylogenetic study of Petaladenium and show it is not part of the large Genistoid clade, but is a new branch of the Amburaneae clade, one of the first-diverging lineages of the Papilionoideae phylogeny. This result is supported by the chemical observation that the quinolizidine alkaloids, a chemical synapomorphy of the Genistoids, are absent in Petaladenium. Parsimony and Bayesian phylogenetic analysis of nuclear ITS/5.8S and plastid matK and trnL intron agree with a new interpretation of morphology that Petaladenium is sister to Dussia, a genus comprising ∼18 species of trees largely confined to rainforests in Central America and northern South America. Petaladenium, Dussia, and Myrospermum have papilionate flowers in a clade otherwise with radial floral symmetry, loss of petals or incompletely differentiated petals. Our phylogenetic analyses also revealed well-supported resolution within the three main lineages of the ADA clade (Angylocalyceae, Dipterygeae, and Amburaneae). We also discuss further molecular phylogenetic evidence for the undersampled Amazonian genera Aldina and Monopteryx, and the tropical African Amphimas, Cordyla, Leucomphalos, and Mildbraediodendron.

Quinolizidine alkaloids reduced mortality in EV71-infected mice by compensating for the levels of T cells.

Recent outbreak of hand, foot and mouse disease caused by enterovirus 71 is a serious threat to infants and children in Asia-Pacific countries. No vaccines or antiviral therapies are available against this infection. In this study, we found that quinolizidine alkaloids could improve the levels of T cells in mice. The structure-activity relationships demonstrated that the oxidation and double bonds are important for the excellent potency. Oxysophocarpine, the most effective compound of six quinolizidine alkaloids, could also relieve symptoms and reduce mortality in lethal enterovirus 71-infected mice through compensating for the decreased levels of T cells. This work suggested that quinolizidine alkaloids have the potential against enterovirus 71 for further development of novel antiviral drugs.

Lupanine Improves Glucose Homeostasis by Influencing KATP Channels and Insulin Gene Expression.

The glucose-lowering effects of lupin seeds involve the combined action of several components. The present study investigates the influence of one of the main quinolizidine alkaloids, lupanine, on pancreatic beta cells and in an animal model of type-2 diabetes mellitus. In vitro studies were performed with insulin-secreting INS-1E cells or islets of C57BL/6 mice. In the in vivo experiments, hyperglycemia was induced in rats by injecting streptozotocin (65 mg/kg body weight). In the presence of 15 mmol/L glucose, insulin secretion was significantly elevated by 0.5 mmol/L lupanine, whereas the alkaloid did not stimulate insulin release with lower glucose concentrations. In islets treated with l-arginine, the potentiating effect of lupanine already occurred at 8 mmol/L glucose. Lupanine increased the expression of the Ins-1 gene. The potentiating effect on secretion was correlated to membrane depolarization and an increase in the frequency of Ca(2+) action potentials. Determination of the current through ATP-dependent K⁺ channels (KATP channels) revealed that lupanine directly inhibited the channel. The effect was dose-dependent but, even with a high lupanine concentration of 1 mmol/L or after a prolonged exposure time (12 h), the KATP channel block was incomplete. Oral administration of lupanine did not induce hypoglycemia. By contrast, lupanine improved glycemic control in response to an oral glucose tolerance test in streptozotocin-diabetic rats. In summary, lupanine acts as a positive modulator of insulin release obviously without a risk for hypoglycemic episodes.

Quinolizidine alkaloids and phomopsin A in animal feed containing lupins: co-occurrence and carry-over into veal products.

Lupins are used in animal feed because of their excellent nutritional composition. Australian and European Lupinus angustifolius seeds are incorporated in compound feed of calves for veal production in Belgium. To investigate the co-occurrence of quinolizidine alkaloids (QAs) and phomopsin A (PHO A) in lupin seeds and lupin-containing feed, and the potential transfer to animal-derived foods, representative samples were obtained from various actors in the chain. A UHPLC-MS/MS method was validated for the simultaneous quantification of seven QAs and PHO A in relevant matrices. Results indicate highly consistent total QA (TQA) levels in Australian lupins (173 ± 24 mg/kg) (n = 25), while European samples showed a high variability (1442 ± 1497 mg/kg) (n = 15). PHO A was detected in 7 of 40 samples. Lupin-containing feed had a mean TQA content of 42 ± 28 mg/kg (n = 20). An in vivo feeding trial demonstrated the transfer of QAs to muscle and liver of calves that were fed the lupin-containing feed. Highest concentrations were found for lupanine in liver tissue samples (67 ± 46 µg/kg). PHO A concentrations were below the LOD in all feed and tissue samples. These results indicate that animal-derived foods (veal meat/liver) are a potential route for QAs to enter the food chain.

Quinolizidine Alkaloids and Isoflavones from the Herb of Thermopsis lupinoides and Their Antiviral, Antifungal, and Insecticidal Activities.

As part of our ongoing investigation of natural bioactive substances from the genus Thermopsis of the tribe Fabaceae for agricultural protection, the chemical constituents of the herb Thermopsis lupinoides were systematically investigated, which led to the isolation of 39 quinolizidine alkaloids (QAs) (1-39), including 14 new QAs (1-14) and 14 isoflavones (40-53). Their structures were elucidated through comprehensive spectroscopic data analysis (IR, UV, NMR, HRESIMS), ECD calculations, and X-ray crystallography. The antitomato spotted wilt virus (TSWV) and antifungal (against Botrytis cinerea, Gibberella zeae, Phytophythora capsica, and Alternaria alternata) and insecticidal (against Aphis fabae and Tetranychus urticae) activities of the isolated compounds were screened using the lesion counting method, mycelial inhibition assay, and spray method, respectively. The bioassay results showed that 34 exhibited excellent protective activity against TSWV, with an EC50 value of 36.04 µg/mL, which was better than that of the positive control, ningnanmycin (86.03 µg/mL). The preliminary mechanistic exploration illustrated that 34 induced systemic acquired resistance in the host plant by acting on the salicylic acid signaling pathway. Moreover, 1 showed significant antifungal activity against B. cinerea (EC50 value of 20.83 µg/mL), while 2 exhibited good insecticidal activity against A. fabae (LC50 value of 24.97 µg/mL). This research is promising for the invention of novel pesticides from QAs with high efficiency and satisfactory ecological compatibility.

Community ecological succession of endophytic fungi associates with medicinal compound accumulation in Sophora alopecuroides.

Endophytic fungi of medicinal plants are symbiotic with the host and play an important role in determining metabolites. To understand the relationship between the accumulation of Sophora alopecuroides' medicinal bioactive compounds and the ecological succession of endophytic fungi, here we collected samples from S. alopecuroides at four developmental stages (adult, flowering, podding, and mature) and different organs (roots, stems, leaves, and seeds) at the mature stage. We then used high-performance liquid chromatography-mass spectrometry and high-throughput sequencing on the internal transcribed spacer region to identify the medicinal compounds and endophytic fungal communities in each sample. The endophytic fungal community characteristics and accumulation of medicinally bioactive compounds of S. alopecuroides varied with the host's developmental stages and organs, with the highest total alkaloids content of 111.9 mg/g at the mature stage. Membership analysis and network connection analysis showed a total of 15 core endophytic fungi in different developmental stages and 16 core endophytic fungi in different organs at the mature stage. The unclassified Ascomycota, Aspergillus, and Alternaria were significantly and positively correlated with the medicinal compounds of S. alopecuroides at the mature stage (r > 0.6 or r < -0.6; P < 0.05). In this study, we identified key endophytic fungal resources that affect the content of medicinally bioactive compounds in S. alopecuroides. This discovery could lay the foundation for enhancing the yield of medicinally bioactive compounds in S. alopecuroides and the development and application of functional endophytic fungi.IMPORTANCESophora alopecuroides is a traditional Chinese herbal medicine. The major medicinal chemicals are considered to be quinolizidine alkaloids. Quinolizidine alkaloids have been widely used for the treatment of tumors, dysentery, and enteritis. Previous studies have found that endophytic fungi in S. alopecuroides can promote the accumulation of host quinolizidine alkaloids. However, the relationship between the accumulation of S. alopecuroides' medicinal bioactive compounds and the ecological succession of endophytic fungi remains unclear. In this study, we screened the key endophytic fungal resources affecting the content of medicinally bioactive compounds and laid the foundation for subsequent research on the mechanism by which endophytic fungi promote the accumulation of medicinally bioactive compounds in S. alopecuroides.

New Analytical Approach to Quinolizidine Alkaloids and Their Assumed Biosynthesis Pathways in Lupin Seeds.

Alkaloids play an essential role in protecting plants against herbivores. Humans can also benefit from the pharmacological effects of these compounds. Plants produce an immense variety of structurally different alkaloids, including quinolizidine alkaloids, a group of bi-, tri-, and tetracyclic compounds produced by Lupinus species. Various lupin species produce different alkaloid profiles. To study the composition of quinolizidine alkaloids in lupin seeds, we collected 31 populations of two wild species native to Israel, L. pilosus and L. palaestinus, and analyzed their quinolizidine alkaloid contents. Our goal was to study the alkaloid profiles of these two wild species to better understand the challenges and prospective uses of wild lupins. We compared their profiles with those of other commercial and wild lupin species. To this end, a straightforward method for extracting alkaloids from seeds and determining the quinolizidine alkaloid profile by LC-MS/MS was developed and validated in-house. For the quantification of quinolizidine alkaloids, 15 analytical reference standards were used. We used GC-MS to verify and cross-reference the identity of certain alkaloids for which no analytical standards were available. The results enabled further exploration of quinolizidine alkaloid biosynthesis. We reviewed and re-analyzed the suggested quinolizidine alkaloid biosynthesis pathway, including the relationship between the amino acid precursor l-lysine and the different quinolizidine alkaloids occurring in seeds of lupin species. Revealing alkaloid compositions and highlighting some aspects of their formation pathway are important steps in evaluating the use of wild lupins as a novel legume crop.

Impacts of Different Processes on the Nutritional and Antinutritional Contents of White and Blue Lupin Seeds and Usage Possibilities for Sustainable Poultry Production.

In the current era, it is important to consider economic and ecological sustainability issues while optimally meeting the nutrient needs of poultry. The use and research of alternative feedstuffs have gained importance due to these factors. The aim of this study is to reveal the raw lupin seeds' nutrient ingredients as an alternative feedstuff and the effects of debittering methods. In the present study, two different treatments (germination for 2 days; heat treatment in an autoclave at 130 °C for 20 min) were applied to white and blue lupin seeds, and the differences in nutrient compositions between them and raw seeds were determined. When fatty acid compositions were analyzed, oleic, γ-linolenic, arachidic, behenic, erucic, and lignoceric acid values were found to be the highest in the raw, autoclaved, and germinated forms of white lupin (p < 0.01). The highest values of palmitic, stearic, and linoleic acids were observed in blue lupin (p < 0.01). While the value of total quinolizidine alkaloids (QA) in raw white lupin grains was higher than 1.943 mg/g, it was higher than 1.800 mg/g in autoclaved and germination-treated grains. Similarly, the total QA value of raw blue lupin grains was 0.894 mg/g, 0.609 ± 0.244 mg/g in germination-treated seeds, and 0.705 ± 0.282 mg/g in autoclave-treated seeds. As a result of these findings, it can be said that the methods applied for the removal of bitterness gave promising results. Furthermore, it would be rewarding to use these lupin varieties in in vitro and in vivo experiments to reveal the impacts and mechanisms of debittering methods on poultry.

Antidermatophytic quinolizidine alkaloids from Calpurnia aurea subsp. aurea (Aiton) Benth.

From the leaves and stem bark of the Kenyan medicinal plant Calpurnia aurea subsp. aurea, four previously undescribed quinolizidine alkaloids namely, 2ß-methoxy-13α-O-(2'-pyrrolylcarbonyl) virgiline, 2α-methoxy-13ß-O-(2'-pyrrolylcarbonyl) virgiline, 3α-O-angelate-2ß-hydroxy-13α-O-(2'-pyrrolylcarbonyl) virgiline, 2,3-dehydro-virgiline were isolated together with four known ones. Structural elucidation of the compounds was based on 1D and 2D NMR spectroscopy and mass spectrometry. Their relative configurations were determined by NOESY correlations and literature. The quinolizidine alkaloids were tested against Trichophyton rubrum, Trichophyton interdigitale, Trichophyton benhamiae, Microsporum canis and Nannizzia gypsea, common causative agents of most of the tinea infections in human. All the isolated quinolizidine alkaloids exhibited antidermatophytic activity with MIC ranging from 37.5 µg/ml to 300 µg/ml.