The effect of casing and gypsum on the yield and psychoactive tryptamine content of Psilocybe cubensis (Earle) Singer

Psychedelic fungi have experienced a surge in interest in recent years. Most notably, the fungal secondary metabolite psilocybin has shown tremendous promise in the treatment of various psychiatric disorders. The mushroom species that produce this molecule are poorly understood. Here we sought to examine for the first time, the response of a psilocybin-producing species Psilocybe cubensis to casing (peat moss and vermiculite) and supplementation with gypsum (calcium sulfate dihydrate), two common practices in commercial mushroom cultivation. Mycelial samples of genetically authenticated P. cubensis were used to inoculate popcorn grain bags. The fully colonized bags of popcorn grain (0.15 kg) were transferred to bins of 0.85 kg pasteurized horse manure, with or without 1 cm thick layer of casing and/or 5 % gypsum. Our results indicate that the use of a casing layer significantly increases the biological efficiency (161.5 %), by approximately four fold, in comparison to control (40.5 %), albeit with a slight delay (∼2 days) for obtaining fruiting bodies and a somewhat reduced total tryptamine content (0.85 %) as gauged by High Performance Liquid Chromatography measurements. Supplementation with both casing and gypsum, however, appears to promote maximal yields (896.6 g/kg of dried substrate), with a biological efficiency of 89.6 %, while also maintaining high total tryptamine expressions (0.95 %). These findings, revealing methods for maximizing yield of harvest and expressions of psychoactive tryptamines, may prove useful for both home growers and commercial cultivators of this species, and ultimately support the growth of a robust industry with high quality natural products.

In silico characterization of the psilocybin biosynthesis pathway

Nearly all mushrooms of the Psilocybe genus contain the natural product psilocybin, which is a psychoactive alkaloid derived from l-tryptophan. Considering their use in ancient times, as well as their psychedelic properties, these mushrooms have re-emerged with psychotherapeutic potential for treating depression, which has triggered increased pharmaceutical interest. However, the psilocybin biosynthesis pathway was only recently defined and, as such, little exists in the way of structural data. Accordingly, the aim of this study was to structurally characterize this pathway by generating homology models for the four Psilocybe cubensis enzymes involved in psilocybin biosynthesis (PsiD, a decarboxylase; PsiH, a monooxygenase; PsiK, a phosphotransferase; PsiM, a methyltransferase). Following initial model generation and alignment with the identified structural templates, repeated refinement of the models was carried out using secondary structure prediction, geometry evaluation, energy minimization, and molecular dynamics simulations in water. The final models were then evaluated using molecular docking interactions with their substrates, i.e., psilocybin precursors (l-tryptophan, tryptamine, 4-hydroxytryptamine, and norbaeocystin/baeocystin), all of which generated feasible binding modes for the expected biotransformation. Further plausibility of the psilocybin → aeruginascin, 4-hydroxytryptamine → norpsilocin, and tryptamine → N,N-dimethyltryptamine conversions, all mediated by the generated model for PsiM, suggests valid routes of formation for these key secondary metabolites. The structural characterization of these enzymes and their binding modes which emerged from this study can lead to a better understanding of psilocybin synthesis, thereby paving the way for the development of novel substrates and selective inhibitors, as well as improved biotechnological manipulation and production of psilocybin in vitro.

Dibenzyl trisulfide induces caspase-independent death and lysosomal membrane permeabilization of triple-negative breast cancer cells

The Petiveria alliacea L. (P. alliacea) plant is traditionally used in folklore medicine throughout tropical regions of the world to treat arthritis, asthma, and cancer. Dibenzyl trisulfide (DTS) is one of the active ingredients within the P. alliacea plant. Triple-negative breast cancer (TNBC) is associated with a poor prognosis, particularly among women of West African ancestry, due in part to limited effective therapy. Though potent anticancer actions of DTS have been reported in a TNBC cell line, the mechanism of DTS-mediated cytotoxicity and cell death remains ill-defined. In the current study, we show that DTS exhibits cytotoxicity in a panel of triple-negative breast cancer (TNBC) cells derived from patients of European and West African ancestry. We found that DTS inhibits proliferation and migration of CRL-2335 cells derived from a patient of West African ancestry. DTS induces the expression of pro-apoptotic genes BAK1, GADD45a, and LTA in CRL2335 cells though it primarily promotes caspase-independent CRL-2335 cell death. DTS also promotes destabilization of the lysosomal membrane resulting in cathepsin B release in CRL-2335 cells. Finally, Kaplan-Meier survival curves reveal that higher expression of BAK1 and LTA in tumors from patients with TNBC is associated with longer relapse-free survival. Collectively, our data suggest that DTS confers promising antitumor efficacy in TNBC, in part, via lysosomal-mediated, caspase-independent cell death to warrant furthering its development as an anticancer agent.

Abstract PO-110: Plant isolate dibenzyl trisulfide induces caspase-independent death in triple negative breast cancer cells derived from patients of West African descent

Patients with triple negative breast cancer (TNBC) possess tumors that lack estrogen receptor, progesterone receptor, and human epidermal growth receptor expression. While these patients traditionally receive chemotherapy to combat this aggressive breast cancer subtype, others use natural remedies. Dibenzyl trisulfide (DTS) is derived from Petiveria alliacea, a perennial shrub that grows in tropical regions of the world. Many TNBC patients residing in the tropics are of West African descent. Therefore, we evaluated the anticancer actions of DTS in TNBC cells, including those derived from patients of West African descent. We found that DTS inhibited TNBC cell viability, migration and proliferation in a dose-dependent manner. Interestingly, DTS blocked the propensity of pro-carcinogen benzo-A-pyrene to induce proliferation of immortalized breast epithelial cells. Moreover, we found that DTS induced early apoptosis in TNBC cells, which was only partially attenuated following pretreatment with pan-caspase inhibitor zVAD-fmk. Though DTS induced pro-apoptotic gene and protein expression along with PARP cleavage, it failed to produce appreciable caspase 3 cleavage and promote significant apoptotic body formation. This suggests that this plant isolate induces caspase-independent and non-apoptotic death of TNBC cells. Furthermore, DTS promoted lysosomal membrane destabilization and cathepsin B release in TNBC cells. Taken together, DTS exhibits promising chemotherapeutic and chemopreventive ability by inducing non-apoptotic TNBC cell death and thwarting TNBC progression, supporting its evaluation in clinical trials as an agent to combat TNBC among patients of West African descent.

Citation Format: Jonathan Wooten, Shaniece Wooten, Cristina Araújo, Joyce Aja, Nicole Mavingire, Rupika Delgoda, Eileen Brantley. Plant isolate dibenzyl trisulfide induces caspase-independent death in triple negative breast cancer cells derived from patients of West African descent [abstract]. In: Proceedings of the AACR Virtual Conference: 14th AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2021 Oct 6-8. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2022;31(1 Suppl):Abstract nr PO-110.

Challenges in the control of neglected insect vector diseases of human importance in the Anglo-Caribbean

INTRODUCTION

Neglected tropical diseases (NTDs) in developing countries like the Caribbean, negatively affect multiple income-generating sectors, including the tourism industry upon which island states are highly dependent. Insect-transmitted NTDs include, but are not limited to, malaria, dengue and lymphatic filariasis. Control measures for these disease, are often ignored because of the associated cost. Many of the developing country members are thus retained in a financially crippling cycle, balancing the cost of prophylactic measures with that of controlling an outbreak.The purpose of the paper is to bring awareness to NTDs transmitted by insects of importance to humans, and to assess factors affecting such control, in the English-speaking Caribbean.

METHOD

Comprehensive literature review on reports pertaining to NTDs transmitted by insects in the Caribbean and Latin America was conducted. Data search was carried out on PubMed, and WHO and PAHO websites.

RESULTS AND CONCLUSION

Potential risk factors for NTDs transmitted by arthropods in the English-speaking Caribbean are summarised. The mosquito appears to be the main insect-vector of human importance within the region of concern. Arthropod-vectors of diseases of veterinary importance are also relevant because they affect the livelihood of farmers, in highly agriculture based economies. Other NTDs may also be in circulation gauged by the presence of antibodies in Caribbean individuals. However, routine diagnostic tests for specific diseases are expensive and tests may not be conducted when diseases are not prevalent in the population. It appears that only a few English-speaking Caribbean countries have examined secondary reservoirs of pathogens or assessed the effectivity of their insect control methods. As such, disease risk assessment appears incomplete. Although continuous control is financially demanding, an integrated and multisectoral approach might help to deflect the cost. Such interventions are now being promoted by health agencies within the region and various countries are creating and exploring the use of novel tools to be incorporated in their insect-vector control programmes.

Dibenzyl trisulfide binds to and competitively inhibits the cytochrome P450 1A1 active site without impacting the expression of the aryl hydrocarbon receptor

The toxicological manifestation of many pollutants relies upon their binding to the aryl hydrocarbon receptor (AHR), and it follows a cascade of reactions culminating in an elevated expression of cytochrome P450 (CYP) 1 enzymes. CYP1A1 and CYP1B1 are associated with enhanced carcinogenesis when chronically exposed to certain polyaromatic hydrocarbons, and their inhibition may lead to chemoprevention. We evaluated dibenzyl trisulfide (DTS), expressed in the ethnomedical plant, Petiveria alliacea, for such potential chemoprevention. Using recombinant human CYP1A1 and CYP1B1 bactosomes on a fluorogenic assay, we first demonstrated that DTS moderately inhibited both enzymes with half maximal inhibitory concentration (IC50) values of 1.3 ± 0.3 and 1.7 ± 0.3 μM, respectively. Against CYP1A1, DTS was a reversible, competitive inhibitor with an apparent inhibitory constant (Ki) of 4.55 ± 0.37 μM. In silico molecular modeling showed that DTS binds with an affinity of -39.8 kJ·mol-1, situated inside the binding pocket, approximately 4.3 Å away from the heme group, exhibiting interactions with phenylalanine residue 123 (Phe-123), Phe-224, and Phe-258. Lastly, zebrafish (Danio rerio) embryos were exposed to 0.08-0.8 μM DTS from 24 to 96 h post fertilization (hpf) with the in vivo ethoxyresorufin-O-deethylase (EROD) assay, and, at 96 hpf, DTS significantly suppressed EROD CYP1A activity in a dose-dependent manner, with up to 60% suppression in the highest 0.8 μM exposure group. DTS had no impact on gene transcription levels for cyp1a and aryl hydrocarbon receptor 2 (ahr2). In co-exposure experiments, DTS suppressed CYP1A activity induced by both B[a]P and PCB-126, although these reductions were not significant. Taken together, these results demonstrate that DTS is a direct, reversible, competitive inhibitor of the carcinogen-activating CYP1A enzyme, binding in the active site pocket close to the heme site, and shows potential in chemoprevention.

Selective cytotoxic and anti-metastatic activity in DU-145 prostate cancer cells induced by Annona muricata L. bark extract and phytochemical, annonacin

BACKGROUND

Annona muricata L. was identified as a popular medicinal plant in treatment regimens among cancer patients in Jamaica by a previously conducted structured questionnaire. Ethnomedically used plant parts, were examined in this study against human prostate cancer cells for the first time and mechanisms of action elucidated for the most potent of them, along with the active phytochemical, annonacin.

METHODS

Nine extracts of varying polarity from the leaves and bark of A. muricata were assessed initially for cytotoxicity using the MTT (3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay on PC-3 prostate cancer cells and the ethyl acetate bark (EAB) extract was identified as the most potent. EAB extract was then standardized for annonacin content using High-performance Liquid Chromatography - Mass Spectrometry (HPLC-MS) and shown to be effective against a second prostate cancer cell line (DU-145) also. The mode of cell death in DU-145 cells were assessed via several apoptotic assays including induction of increased reactive oxygen species (ROS) production, reduction of mitochondrial membrane potential, activation of caspases and annexin V externalization combined with morphological observations using confocal microscopy. In addition, the potential to prevent metastasis was examined via inhibition of cell migration, vascular endothelial growth factor (VEGF) and angiogenesis using the chorioallantoic membrane assay (CAM).

RESULTS

Annonacin and EAB extract displayed selective and potent cytotoxicity against the DU-145 prostate carcinoma cells with IC50 values of 0.1 ± 0.07 μM and 55.501 ± 0.55 μg/mL respectively, without impacting RWPE-1 normal prostate cells, in stark contrast to chemotherapeutic docetaxel which lacked such selectivity. Docetaxel's impact on the cancerous DU-145 was improved by 50% when used in combination with EAB extract. Insignificant levels of intracellular ROS content, depolarization of mitochondrial membrane, Caspase 3/7 activation, annexin V content, along with stained morphological evaluations, pointed to a non-apoptotic mode of cell death. The extract at 50 μg/mL deterred cell migration in the wound-healing assay, while inhibition of angiogenesis was displayed in the CAM and VEGF inhibition assays for both EAB (100 μg /mL) and annonacin (0.5 μM).

CONCLUSIONS

Taken together, the standardized EAB extract and annonacin appear to induce selective and potent cell death via a necrotic pathway in DU-145 cells, while also preventing cell migration and angiogenesis, which warrant further examinations for mechanistic insights and validity in-vivo.

Hypotensive and antihypertensive effects of an aqueous extract from Guinep fruit (Melicoccus bijugatus Jacq) in rats

Melicoccus bijugatus Jacq (Mb) has been reported to have cardiovascular modulatory effects. In this study, we evaluated the antihypertensive effects and mechanism of action of Mb on N^G-Nitro-l-arginine Methyl Ester (l-NAME) and Deoxycorticosterone Acetate (DOCA) rat models. Aqueous extract of Mb fruit (100 mg/kg) was administered for 6 weeks to rats by gavage and blood pressure was recorded. Effects of the extract on vascular reactivity was evaluated using isolated organ baths, and tissues were collected for biochemical and histological analysis. The systolic blood pressure (SBP), diastolic blood pressure (DBP) and mean arterial pressure (MAP) were significantly (P < 0.05) reduced with extract (100 mg/kg) administration and treatment compared to the hypertensive models. Mb (100 µg/mL) reduced the vascular contractility induced by phenylephrine (PE), and caused a dose-dependent relaxation of PE-induced contraction of aortic vascular rings. The vasorelaxation properties seemed to be endothelium dependent, as well as nitric oxide (NO) and guanylyl cyclase, but not prostaglandin dependent. Histomicrograph of transverse sections of the ventricles from the Mb group did not show abnormalities. The extract significantly (P < 0.05) reduced an l-NAME induced elevation of cardiac output and Creatine Kinase Muscle-Brain (CKMB), but had no significant impact on the activities of arylamine N-acetyltransferase. In conclusion, Mb significantly decreased blood pressure in hypertensive models. The extract possesses the ability to induce endothelium dependent vasodilation, which is dependent on guanylyl cyclase but not prostaglandins.

Abstract 6553: Plant power: Plant isolate dibenzyl trisulfide induces death of triple-negative breast cancer cells derived from an African American patient

Triple negative breast cancer (TNBC), characterized by tumors that lack estrogen receptor, progesterone receptor, and human epidermal growth receptor expression, represents one of the most aggressive subtypes of breast cancer. TNBC carries a poor prognosis due, in part, to a lack of clinically available targeted therapy. Novel therapeutic strategies to combat TNBC primarily involve the use of synthetic small molecules. However, the World Health Organization reports that there is increased use of natural remedies and traditional medicine to treat diseases. Our lab has investigated the chemotherapeutic and chemopreventive effects of a variety of plant isolates. Dibenzyl trisulfide (DTS) is derived from Petiveria alliacea, a perennial shrub that grows in tropical regions of the world. Previous investigations surrounding DTS are limited to anticancer actions in European American breast cancer cells. The purpose of this study was to evaluate the anticancer actions of DTS in CRL-2335 cells which are derived from an African American patient with TNBC. We found that DTS inhibited TNBC cell migration and proliferation using wound healing and colony forming assays. Furthermore, we found DTS induced apoptotic body formation and nuclear fragmentation using relief contrast and fluorescence microscopy respectively. Moreover, using the Annexin V/PI assay we found that DTS induced early apoptosis, which was partially attenuated in cells pretreated with pan-caspase inhibitor zVAD-fmk. Finally, quantitative polymerase chain reaction analyses revealed that DTS induced the expression of pro-apoptotic genes BAK1, LTA and GADD45A. Our data suggest that DTS effectively induces caspase-independent death of TNBC cells derived from an African American patient and represents a promising agent to treat more refractory forms of breast cancer.

Citation Format: Jonathan Wooten, Cristina Araújo, Shaniece Wauchope, Joyce Aja, Nicole Mavingire, Rupika Delgoda, Eileen Brantley. Plant power: Plant isolate dibenzyl trisulfide induces death of triple-negative breast cancer cells derived from an African American patient [abstract]. In: Proceedings of the Annual Meeting of the American Association for Cancer Research 2020; 2020 Apr 27-28 and Jun 22-24. Philadelphia (PA): AACR; Cancer Res 2020;80(16 Suppl):Abstract nr 6553.

Abstract C126: Plant isolate dibenzyl trisulfide potently inhibits cytochrome P450 1 enzyme activity and the growth of breast cancer cells derived from African American patients

Triple-negative breast cancer (TNBC), characterized by tumors that lack expression of the estrogen receptor (ER), progesterone receptor (PR), and human epidermal growth factor receptor 2 (HER2), carries a poor prognosis. African American women develop TNBC at disproportionately higher rates than women of other ethnic groups. Dibenzyl trisulfide (DTS), found expressed in the Jamaican plant Petiveria alliacea, has been shown to inhibit the growth of several cancer types. However, little is known about whether this plant isolate displays anticancer activity in TNBC cells from African American patients or modulates cytochrome P450 1 (CYP1) enzyme activity. This work, as part of an ongoing ethnopharmacology-based bioactivity screening, was designed to fill this deficit. African American TNBC (AA-TNBC) cells HCC1806 and MDA-MB-468 were treated with varying concentrations of DTS for 48 h and cell viability was assessed using the Alamar Blue assay. DTS potently inhibited the growth of HCC1806 and MDA-MB-468 cells, producing IC50 values of 10.6 ± 1.2μM and 10.3 ± 2.0μM, respectively. Additionally, we discovered that DTS induced apoptosis in these cells. Furthermore, we investigated the ability DTS to impact the activities of the CYP1 family of enzymes, which are known to convert procarcinogens to carcinogens. The IC50 values obtained for CYPs 1A1, 1A2 and 1B1 were 1.68 ± 0.3μM, 1.9 ± 0.2μM and 1.29 ± 0.3μM, respectively. These data indicate DTS exhibits potent inhibition of the activities of these enzymes. In particular, DTS was able to bind to CYP1A2 in accordance with irreversible kinetics. In addition, DTS reduced CYP1 mRNA expression in both cell lines. Our findings provide a rationale for in vivo evaluations of DTS as a potential candidate for chemoprevention and for treating AA-TNBC patients.

Citation Format: Jonathan V. Wooten, Shaniece Wauchope, Nicole Mavingire, Petreena Campbell, JéAnn Watson, Maxine Gossell-Williams, Rupika Delgoda, Eileen Brantley. Plant isolate dibenzyl trisulfide potently inhibits cytochrome P450 1 enzyme activity and the growth of breast cancer cells derived from African American patients [abstract]. In: Proceedings of the Eleventh AACR Conference on the Science of Cancer Health Disparities in Racial/Ethnic Minorities and the Medically Underserved; 2018 Nov 2-5; New Orleans, LA. Philadelphia (PA): AACR; Cancer Epidemiol Biomarkers Prev 2020;29(6 Suppl):Abstract nr C126.

Reliance on medicinal plant therapy among cancer patients in Jamaica

PURPOSE

Patients' perspective of their treatment regime plays a vital role in its success. Recognizing the high prevalence of medicinal plant usage among Jamaicans at large, we investigated the engagement of such remedies by cancer patients, with the aim of uncovering self-medicating habits, perceptions and details of utilized plants.

METHODS

A structured, interviewer-based questionnaire was administered to 100 patients attending the oncology and urology clinics at the University Hospital of the West Indies in Kingston, Jamaica. A method of convenience sampling was employed and the data were analyzed using summary statistics and statistical significance tests.

RESULTS

A large proportion (n = 80, 80%) of interviewed patients, engaged medicinal plants in their treatment regimes. Such habits were independent of person's education, economic status and were higher among the 55-74 age groups (p < 0.05) compared with younger patients. The use of herbs was hinged on the patient's strong sense of tradition and positive perspective of herbal efficacy (88%), fueled by anecdotal accounts from fellow patients. Majority of such users (74.7%) were under concomitant treatment with a prescription medicine, and worryingly, only 15% of patients made their oncologists aware. Annona muricata L. and Petiveria alliacea L. were the most commonly used plants for treating breast and prostate cancers, respectively.

CONCLUSION

A large proportion of Jamaican cancer patients use medicinal plants in self-medicating practices and their perceptions and habits need to be considered by physicians, in the design of safe and effective care regimes.

Two New Oxodolastane Diterpenes from the Jamaican Macroalga Canistrocarpus cervicornis

The chemical investigation of the organic extract of Canistrocarpus cervicornis, collected at Drunken Man's Cay at Port Royal, Jamaica, has led to the isolation of two new dolastane diterpenes 4R-acetoxy-8S,9S-epoxy-14S-hydroxy-7-oxodolastane (1) and 4R-hydroxy-8S,9S-epoxy-14S-hydroxy-7-oxodolastane (2) and the previously isolated dolastane (4R,9S,14S)-4,9,14-trihydroxydolast-1(15),7-diene (3) as a major diterpene constituent. The structures of the new compounds were elucidated by extensive spectroscopic analyses. Compounds 1-3 were evaluated for their cytotoxicity against human tumor cell lines PC3 and HT29. The results revealed that the dolastane diterpenes (1-3) displayed moderate, concentration dependent, cytotoxicity.

Aqueous extract from leaf of Artocarpus altilis provides cardio-protection from isoproterenol induced myocardial damage in rats: Negative chronotropic and inotropic effects

ETHNOPHARMACOLOGICAL RELEVANCE

The leaves of Artocarpus altilis (Parkinson ex F.A.Zorn, Fosberg) (Moraceae) are used in the management of hypertension; this study assessed the cardio-protective effects of the leaf extract on isoproterenol (ISO) induced myocardial damage in rats.

MATERIAL AND METHODS

Twenty (20) adult male Sprague-Dawley rats (175-230g) were divided into 5 groups. Group 1 (Control), 2 (AA) received 50mg/Kg Artocarpus altilis (AA) only; 3 (ISO) received 85mg/Kg ISO only; 4 (ISO+AA/50) and 5 (ISO+AA/100) received 50 and 100mg/Kg AA respectively for 6 days, after induced with ISO twice (85mg/Kg) at a 24-h period. Blood pressure readings were taken before and after the administering of ISO using the tail cuff method. ECG was performed on anaesthetized rats. Cardiac contractility was measured in isolated right atrial muscles. Assessment of myocardial infarct (MI) size, heart/body weight ratio, biochemical, hematological and histo-morphological parameters were conducted at the end of seven days. An aqueous extract from leaves of A. altilis was analyzed for organic compounds using UHPLC mass spectrometry.

RESULTS

ISO induced myocardial damage through an elevation of the heart rate (HR), infarct size and ECG distortions. Treatment with AA significantly (p˂0.05) reduced heart/body weight ratio (49%), MI (96%), HR (27%), sympathovagal imbalance (36%) and serum cardiac biomarkers (AST, LDH, HDL, triglycerides and CCK) caused by ISO. AA decreased the beat frequency of isolated right atrium (11%) cause by ISO, an action similar to propranolol (beta-adrenergic antagonist; 20%), but showed no significant changes in the QTc intervals of the ECG (suggesting no cardio-toxic drug-herb interactions), Thirty nine compounds were detected using high resolution LC-MS analysis (HPLC-Orbitrap-APCI-MS) in the extract. Pure compounds, as gallic acid and rutin, presented a higher negative chronotropic effect, similar to propranolol.

CONCLUSION

Oral administration of aqueous extract of Artocarpus artilis has cardio-protective functions in myocardial injury, in part, by decreasing the HR, reduced contractility and infarct size. These findings may explain the cardio-protective use of A. altilis in traditional medicine.

Glaucarubulone glucoside from Castela macrophylla suppresses MCF-7 breast cancer cell growth and attenuates benzo[a]pyrene-mediated CYP1A gene induction

Quassinoids often exhibit antioxidant and antiproliferative activity. Emerging evidence suggests that these natural metabolites also display chemopreventive actions. In this study, we investigated the potential for the quassinoid glaucarubulone glucoside (Gg), isolated from the endemic Jamaican plant Castela macrophylla (Simaroubaceae), to display potent cytotoxicity and inhibit human cytochrome P450s (CYPs), particularly CYP1A enzymes, known to convert polyaromatic hydrocarbons into carcinogenic metabolites. Gg reduced the viability of MCF-7 breast adenocarcinoma cells (IC₅₀ = 121 nm) to a greater extent than standard of care anticancer agents 5-fluorouracil, tamoxifen (IC₅₀ >10 μm) and the tamoxifen metabolite 4-hydroxytamoxifen (IC₅₀ = 2.6 μm), yet was not cytotoxic to non-tumorigenic MCF-10A breast epithelial cells. Additionally, Gg induced MCF-7 breast cancer cell death. Gg blocked increases in reactive oxygen species in MCF-10A cells mediated by the polyaromatic hydrocarbon benzo[a]pyrene (B[a]P) metabolite B[a]P 1,6-quinone, yet downregulated the expression of genes that promote antioxidant activity in MCF-7 cells. This implies that Gg exhibits antioxidant and cytoprotective actions in non-tumorigenic breast epithelial cells and pro-oxidant, cytotoxic actions in breast cancer cells. Furthermore, Gg inhibited the activities of human CYP1A according to non-competitive kinetics and attenuated the ability of B[a]P to induce CYP1A gene expression in MCF-7 cells. These data indicate that Gg selectively suppresses MCF-7 breast cancer cell growth without impacting non-tumorigenic breast epithelial cells and blocks B[a]P-mediated CYP1A induction. Taken together, our data provide a rationale for further investigations of Gg and similar plant isolates as potential agents to treat and prevent breast cancer. Copyright © 2017 John Wiley & Sons, Ltd.

TRAMIL ethnomedicinal survey in Jamaica

ETHNOPHARMACOLOGICAL RELEVANCE

A survey was undertaken in Jamaica to document medicinal plants frequently used in the treatment or prophylaxis of illness and trends in their use, following the methodology established by the TRAMIL network. TRAMIL, a Caribbean-wide applied research programme, scientifically evaluates and documents the efficacy and safety of medicinal plant remedies used for primary health care. Initial results from this survey, on an aspect of safety, focusing on the concomitant use and prevalence of medicinal plant use in combination with pharmaceutical drugs in Jamaica, were published in an earlier paper in 2011. This paper now reports survey results on the ethnobotanical use of medicinal plants by Jamaicans.

MATERIALS AND METHODS

A survey using a structured and modified TRAMIL questionnaire was administered to 407 adults selected randomly from systematically selected households within randomly selected clusters. The clusters were selected from each of the three areas that were purposefully selected.

KEY FINDINGS

Respondents identified their use of 107 botanically identified medicinal plants distributed in 51 plant families to treat illnesses or maintain health in the previous twelve months. Fourteen plants, with significant use equal to or greater than 20% for a specified health issue were shortlisted, representing Jamaica׳s first submission to the TRAMIL database. Andrographis paniculata (Burm. f.) Nees (Rice Bitters) was reported as a plant remedy with significant use for the first time in a TRAMIL survey. Informant consensus factor (ICF) values were high for a number of health issues such as mental health (nerves, insomnia, etc.), respiratory system (cold/flu/cough etc.) and for health maintenance with tonics (washout and blood cleanse), indicating strong cultural coherence in medicinal plant selection for these categories. Forty two per cent (113/270) of medicinal plant users utilised mixtures, combining more than one plant. Leaf material was the most commonly used plant part (69%), with fresh material (98%) most commonly prepared as a tea for internal use by decoction (87%). The majority of medicinal plant respondents sourced plants from their backyards (75%) and cited grandmothers (33%) and mothers (32%) as their main sources of information. Jamaicans reported limited use of complementary and alternative medicine (CAM), supporting the assertion that a significant number of citizens in developing countries continue to rely on the use of medicinal plants for primary healthcare.

CONCLUSIONS

Medicinal plant use continues to play an important role in primary healthcare in Jamaica. Fourteen plant remedies with significant use are reported, five previously reported elsewhere and recommended (REC) for the same health condition. Eight plant remedies, including one Jamaican endemic, are reported for different health issues for the first time to TRAMIL and will be investigated (INV) for the new health conditions, together with one plant remedy reported for the first time. This latest survey will be followed by literature reviews, appropriate laboratory screens (TRIG) and community outreach activities (TRADIF) in Jamaica.

Hyptis verticillata Jacq: a review of its traditional uses, phytochemistry, pharmacology and toxicology

ETHNOPHARMACOLOGICAL RELEVANCE

Hyptis verticillata Jacq. (Lamiaceae) (John Charles) is an important medicinal plant with a long history of traditional use, originating in Central America and now extending from Florida to Colombia and across the Caribbean. Records of its earliest use date back to the ancient Mayan and Aztec cultures of Mesoamerica. There is no indication that this plant is being used outside of the Americas.

AIM OF THE REVIEW

This review aims to provide a comprehensive overview of the traditional use, phytochemistry, pharmacological activity and toxicology of Hyptis verticillata and to highlight the opportunities for greater development of the plant's medicinal properties at a local and international level.

MATERIALS AND METHODS

An extensive and systematic review of the literature was undertaken and all relevant abstracts and full-text articles analysed and included in the review.

KEY FINDINGS

A wide range of traditional uses are cited in the literature, from internal uses for conditions affecting the respiratory system, digestive tract and gynaecological system to external uses for conditions affecting the skin and musculoskeletal system. Pharmacological studies to date have demonstrated significant activity which support the traditional use of the plant as an antiinflammatory, antimicrobial, antisecretory agent and hormone modulator. In addition studies have identified anti-cancer, acaricidal, insecticidal and molluscicidal activity. No clinical trials had been completed at the time of this review. A number of key phytochemicals have been isolated, identified and published to date including: 17 lignans; 4 triterpenes; 11 diterpenes, 3 sesquiterpenes, 3 monoterpenes, 2 flavonoids, 1 polyphenol and 1 alkaloid. Nine of these phytochemicals are novel to Hyptis verticillata. Plant extracts and isolated phytochemicals exhibit a broad range of activities that include: antimitotic; antiproliferative; cytotoxic; antioxidant; antiinflammatory; antibacterial; antifungal; antiviral; anti-HIV; antisecretory; hepatoprotective; insecticidal and acaricidal.

CONCLUSIONS

Hyptis verticillata is a medicinal plant with current widespread traditional use in the Americas that warrants further research, clinical trials and product development to fully exploit its medicinal value.

Antiproliferative activity and absolute configuration of zonaquinone acetate from the Jamaican alga Stypopodium zonale

The chemical investigation of specimens of the Jamaican brown alga Stypopodium zonale led to the isolation of a cytotoxic compound, zonaquinone acetate (1), along with known compounds flabellinone, not previously identified in S. zonale, stypoldione, 5',7'-dihydroxy-2'-pentadecylchromone and sargaol. The structures of the metabolites were established by analysis of the spectral data including 1D and 2D NMR experiments while the stereochemistry of 1 was assessed by VCD measurements. Cytotoxic activity was reported in vitro for 1 against breast cancer and colon cancer cell lines at IC(50) values of 19.22-21.62 μM and 17.11-18.35 μM respectively, comparing favorably with standard treatments tamoxifen (17.22-17.32 μM) and fluorouracil (27.03-31.48 μM). When tested with liver cancer cells (Hep G2), no activity was observed. Weak antioxidant activity was observed with 1 but sargaol exhibited high activity.

Possible mechanisms of action of the aqueous extract of Artocarpus altilis (breadfruit) leaves in producing hypotension in normotensive Sprague-Dawley rats

CONTEXT AND OBJECTIVES

Artocarpus altilis (Parkinson) Fosberg (Moraceae) (breadfruit) leaves are used as an antihypertensive remedy. We investigated the possible mechanisms of action of its aqueous extract and its effect on cytochromes P450 (CYP) enzyme activities.

MATERIALS AND METHODS

Intravenous administration of an aqueous leaf extract (20.88-146.18 mg/kg) of A. altilis on mean arterial pressure and heart rate were recorded via cannulation of the carotid artery on anaesthetized normotensive Sprague-Dawley rats. Recordings of the contractile activity of the aortic rings to the extract (0.71-4.26 mg/mL) were studied using standard organ bath techniques. Inhibitions of human CYP3A4 and CYP2D6 enzyme activities were evaluated by means of a fluorometric assay in 96 well plates using heterologously expressed microsomes.

RESULTS

A. altilis caused significant (p < 0.05) hypotensive and bradycardiac responses unaffected by atropine (2 mg/kg) and mepyramine (5 mg/kg), but attenuated by propranolol (1 mg/kg) and N(G)-nitro-L-arginine methyl ester (5 mg/kg). The extract (0.71-4.26 mg/mL) significantly (p < 0.05) relaxed phenylephrine (10⁻⁹-10⁻⁴ M) and 80 mM KCl-induced contractions in endothelium intact and denuded aortic rings; and caused a significant (p < 0.05) rightward shift of the Ca²⁺ dose-response curves in Ca²⁺-free Kreb's solution. Moderate inhibitions of cytochrome P450s (CYP3A4 and CYP2D6) enzyme activities with IC₅₀ values of 0.695 ± 0.187 and 0.512 ± 0.131 mg/mL, respectively, were produced.

CONCLUSION

A. altilis exhibits negative chronotropic and hypotensive effects through α-adrenoceptor and Ca²⁺ channel antagonism. Drug adversity effects are unlikely if the aqueous leaf extract is consumed with other medications reliant on CYP3A4 and CYP2D6 metabolism. This study thus provides scientific evidence for the use of the breadfruit in the treatment of hypertension.

Cytotoxic and potent CYP1 inhibitors from the marine algae Cymopolia barbata

Background

Extracts from the marine algae Cymopolia barbata have previously shown promising pharmacological activity including antifungal, antitumor, antimicrobial, and antimutagenic properties. Even though extracts have demonstrated such bioactivity, isolated ingredients responsible for such bioactivity remain unspecified. In this study, we describe chemical characterization and evaluations of biological activity of prenylated bromohydroquinones (PBQ) isolated from the marine algae C. barbata for their cytotoxic and chemopreventive potential.

Methods

The impact of PBQs on the viability of cell lines (MCF-7, HT29, HepG, and CCD18 Co) was evaluated using the MTS assay. In addition, their inhibitory impact on the activities of heterologously expressed cytochrome P450 (CYP) enzymes (CYP1A1, CYP1A2, CYP1B1, CYP2C19, CYP2D6, and CYP3A4) was evaluated using a fluorescent assay.

Results

7-Hydroxycymopochromanone (PBQ1) and 7-hydroxycymopolone (PBQ2) were isolated using liquid and column chromatography, identified using ¹ H and ¹³ C NMR spectra and compared with the spectra of previously isolated PBQs. PBQ2 selectively impacted the viability of HT29, colon cancer cells with similar potency to the known chemotherapeutic drug, fluorouracil (IC_50, 19.82 ± 0.46 μM compared to 23.50 ± 1.12 μM, respectively) with impact toward normal colon cells also being comparable (55.65 ± 3.28 compared to 55.51 ± 3.71 μM, respectively), while PBQ1 had no impact on these cells. Both PBQs had potent inhibition against the activities of CYP1A1 and CYP1B1, the latter which is known to be a universal marker for cancer and a target for drug discovery. Inhibitors of CYP1 enzymes by virtue of the prevention of activation of carcinogens such as benzo-a-pyrene have drawn attention as potential chemopreventors. PBQ2 potently inhibited the activity of CYP1B1 (IC₅₀ 0.14 ± 0.04 μM), while both PBQ1 and PBQ2 potently inhibited the activity of CYP1A1 (IC₅₀s of 0.39 ± 0.05 μM and 0.93 ± 0.26 μM, respectively). Further characterizations showed partial noncompetitive enzyme kinetics for PBQ2 with CYP1B1 with a K_i of 4.7 × 10^–3 ± 5.1 × 10^–4 μM and uncompetitive kinetics with CYP1A1 (K_i = 0.84 ± 0.07 μM); while PBQ1 displayed partial non competitive enzyme kinetics with CYP1A1 (K_i of 3.07 ± 0.69 μM), noncompetitive kinetics with CYP1A2 (K_i = 9.16 ± 4.68 μM) and uncompetitive kinetics with CYP1B1 (K_i = 0.26 ± 0.03 μM) .

Conclusions

We report for the first time, two isolated ingredients from C. barbata, PBQ1 and PBQ2, that show potential as valuable chemotherapeutic compounds. A hydroxyl moiety resident in PBQ2 appears to be critical for selectivity and potency against the cancer colon cells, HT29, in comparison to the three other malignant cell lines studied. PBQs also show potency against the activities of CYP1 enzyme which may be a lead in chemoprevention. This study, the first on isolates from these marine algae, exemplifies the value of searching within nature for unique structural motifs that can display multiple biological activities.

The prevalence of herbal medicine home use and concomitant use with pharmaceutical medicines in Jamaica

ETHNOPHARMACOLOGICAL RELEVANCE

The work described in this paper aimed to study the prevalence of herbal medicine use in treating illness and concomitant use with pharmaceutical medicines in Jamaica.

MATERIALS AND METHODS

A survey using a structured questionnaire was administered by a trained interviewer to randomly selected adults in systematically selected households within randomly selected urban and rural clusters. Categorical data analysis was performed using Stata version 10 software.

RESULTS

91.4%(372/407) of selected people agreed to participate. 72.6%(270/372) self-medicated with herbs within the previous year. Commonly treated were illnesses of the respiratory system (RS, 77.8%(210/270)), gastro-intestinal tract (GIT, 53.3%(144/270)) and health maintenance using tonics (29.6%(80/270)). 26.7%(72/270) of respondents used pharmaceuticals concomitantly with medicinal plants. Commonly treated were illnesses of the RS (20.4%(55/270)), GIT (13.7%(37/270)) and hypertension (10.0%(27/270)). 19.4% (14/72) of physicians knew of such practices. There was significant association of herb use with/without drugs with age (p<0.001), employment status (p<0.001), religion (p=0.004), gender (p=0.02) and educational level (p=0.031). Thus prevalence of herb use alone was greatest amongst people aged 35-44 and 45-54 years; those employed; Rastafarians; those without health insurance; males and people who had completed secondary education. Whilst prevalence of concomitant herb-drug use was greater amongst people aged 65 years and older; those retired; those of religions other than Rastafarians and Christians, females and people who had attained primary education and below.

CONCLUSIONS

Self-medication with herbs in Jamaica is highly prevalent and highest for self-limiting conditions of the RS, GIT and health maintenance with tonics. Concomitant herb and drug use is highest for self-limiting conditions of the RS, GIT and hypertension, and the use of combined therapy highlights the need for investigations on potential drug-herb interactions. Physicians have limited awareness and knowledge of such concomitant usage, further highlighting the need for increased dialogue with patients, knowledge of medicinal plants and their uses and a heightened pharmacovigilance to avoid adversities that may arise from potential drug-herb interactions.

The prevalence of herbs use in conjunction with conventional medicines in Jamaica

Due to the global rise in the popularity of herbal medicines, adversities resulting from concomitant use of both prescription drugs and herbs are becoming an increasingly important public health issue.

OBJECTIVES

To estimate the prevalence of the use of herbal medicines among persons on prescription medicines in Jamaica. Findings are thought to aid in estimates of the risk of adversities from drug-herb interactions through laboratory investigations and to provide awareness among policy makers responsible for the design of appropriate pharmacovigilance systems in the country.

METHODS

A survey was conducted in eighteen pharmacies throughout Jamaica and patients or parents/carers of children who were on at least one prescription medicine were administered a structured questionnaire by trained interviewers.

RESULTS

Of 399 persons invited to participate in the study 365 (91.5% response rate) agreed to do so and were included in the study. This study population consisted of 306 adults and 60 children and of that 243 adults (80.6%) and 45 children (75.6%) engaged in the concomitant use of herbs and drugs. Patients with a variety of disease conditions, in both rural and urban environs engaged in concomitant herb-drug use. Persons with higher salary (P<0.1) and those with health insurance (P<0.02) tended to have a lower prevalence of herb-drug concomitant use. Among persons indicating such practices the most commonly cited reason for concurrent use of prescription medicine and herbal preparations was the belief that there was no harm in taking both (269, 94.0%) followed by the belief that the prescription medicine alone was not adequate cure (211, 71%). Only 55 (18%) respondents who practised such co-medication indicated that their doctors knew of their use of herbal preparations.

CONCLUSION

There is a high prevalence of herb-drug concomitant use in Jamaica, and an awareness within the medical community and those monitoring adversities would serve well to mitigate risks from potential drug-herb interactions.

Inhibition of CYP1A1 by Quassinoids found in Picrasma excelsa

Infusions of the plant Picrasma excelsa, known as Jamaican bitterwood tea, are commonly consumed to lower blood sugar levels in diabetics who are already on prescription medicines. We therefore investigated the inhibition properties of this tea against a panel of cytochrome P450 (CYP) enzymes, which are primarily responsible for the metabolism of a majority of drugs on the market. The two major ingredients, quassin and neoquassin, were then isolated and used for further characterization. Inhibition of the activities of heterologously expressed CYP microsomes (CYPs 2D6, 3A4, 1A1, 1A2, 2C9, and 2C19) was monitored, and the most potent inhibition was found to be against CYP1A1, with IC (50) values of 9.2 microM and 11.9 microM for quassin and neoquassin, respectively. The moderate inhibition against the CYP1A1 isoform by quassin and neoquassin displayed partial competitive inhibition kinetics, with inhibition constants ( K(i)) of 10.8 +/- 1.6 microM, for quassin and competitive inhibition kinetics, with a K(i) of 11.3 +/- 0.9 microM, for neoquassin. We then docked these two inhibitors into the active site of a model of CYP1A1, which provided insight at the atomic level into the structure-activity relationship of quassinoids with respect to this important CYP isoform known to be an activator of carcinogens, thus providing a useful basis for the search for more potent inhibitors of CYP1A1 that may have implications in chemoprotection.

Herbal interactions involving cytochrome p450 enzymes: a mini review

The metabolism of a drug can be altered by another drug or foreign chemical, and such interactions can often be clinically significant. Cytochrome P450 (CYP) enzymes, a superfamily of enzymes found mainly in the liver, are involved in the metabolism of a plethora of xenobiotics and have been shown to be involved in numerous interactions between drugs and food, herbs and other drugs. The observed induction and inhibition of CYP enzymes by natural products in the presence of a prescribed drug has (among other reasons) led to the general acceptance that natural therapies can have adverse effects, contrary to the popular beliefs in countries where there is an active practice of ethnomedicine. Herbal medicines such as St. John's wort, garlic, piperine, ginseng, and gingko, which are freely available over the counter, have given rise to serious clinical interactions when co-administered with prescription medicines. Such adversities have spurred various pre-clinical and in vitro investigations on a series of other herbal remedies, with their clinical relevance remaining to be established. Although the presence of numerous active ingredients in herbal medicines, foods and dietary supplements complicate experimentation, the observable interactions with CYP enzymes warrant systematic studies, so that metabolism-based interactions can be predicted and avoided more readily. This article highlights the involvement of CYP enzymes in metabolism-related drug-herb interactions and the importance of gaining a mechanism-based understanding to avoid potential adverse drug reactions, in addition to outlining other contributory factors, such as pharmacogenetics and recreational habits that may compound this important health issue.

The practice of polypharmacy involving herbal and prescription medicines in the treatment of diabetes mellitus, hypertension and gastrointestinal disorders in Jamaica

The interference in the metabolism of a drug by another drug, food or other foreign chemical is commonly observed and often leads to clinically significant adverse drug reactions. In Jamaica, there is an extensive use of natural products as medicines, although there is little information on whether natural medicines are used along with prescription medicines, which might increase the likelihood of drug adversities. This current pilot survey was initiated to gain information on the prevalence of such polypharmacy practices. Two concurrent surveys were carried out in Kingston (an urban parish) and Clarendon (a rural parish) in 743 patients above age 14 years with diabetes mellitus, hypertension and gastrointestinal disorders of persons who visited health centres and pharmacies. Patrons visiting these places at various times of the day were informed of the nature of the questionnaire and willing participants with the above disease conditions and who were on prescription medicines were included in the survey. The results indicated that 80% of the respondents reported combining natural products in their treatment along with prescription medicines, with only 13% of those patients informing their physicians of such practices. Such polypharmacy practices were independent of the type of disease among both males and females and was statistically most prevalent (p < 0.001) in the 47-57-year age group. There was a significant association (p < 0.001) between such treatment practices and place of residence with 92% of the rural community engaging in polypharmacy but 70% of the urban did likewise. Therefore, being aware of the prevalence of multiple therapy practices would be especially useful when designing a pharmaco-vigilance system.

NMR investigation of the catalytic mechanism of arylamine N-acetyltransferase from Salmonella typhimurium

Arylamine N-acetyltransferases (NAT) are a family of enzymes found in both eucaryotes and procaryotes, which catalyse the N-acetylation of a range of arylamine and hydrazine drugs and carcinogenic arylamines, using acetyl Coenzyme A as a cofactor. Here we describe a nuclear magnetic resonance (NMR) investigation of the interaction of substrates with Salmonella typhimurium NAT. For solution NMR investigations, pure recombinant NAT from S. typhimurium was used at up to 0.1 mM. We demonstrate that a hydrazine substrate, isoniazid (INH), binds to the protein in the absence of the cofactor, acetyl CoA, and thereby suggest that even though the catalysis may follow a ping-pong pathway, ligand-enzyme interactions can occur in the absence of acetyl CoA.

Structure of arylamine N-acetyltransferase reveals a catalytic triad

Enzymes of the arylamine N-acetyltransferase (NAT) family are found in species ranging from Escherichia coli to humans. In humans they are known to be responsible for the acetylation of a number of arylamine and hydrazine drugs, and they are strongly linked to the carcinogenic potentiation of certain foreign substances. In prokaryotes their substrate specificities may vary and members of the gene family have been linked to pathways including amide synthesis during rifamycin production. Here we report the crystal structure at 2.8 A resolution of a representative member of this family from Salmonella typhimurium in the presence and absence of a covalently bound product analog. The structure reveals surprising mechanistic information including the presence of a Cys-His-Asp catalytic triad. The fold can be described in terms of three domains of roughly equal length with the second and third domains linked by an interdomain helix. The first two domains, a helical bundle and a beta-barrel, make up the catalytic triad using a structural motif identical to that of the cysteine protease superfamily.

Cloning and characterization of arylamine N-acetyltransferase genes from Mycobacterium smegmatis and Mycobacterium tuberculosis: increased expression results in isoniazid resistance

Arylamine N-acetyltransferases (NATs) are found in many eukaryotic organisms, including humans, and have previously been identified in the prokaryote Salmonella typhimurium. NATs from many sources acetylate the antitubercular drug isoniazid and so inactivate it. nat genes were cloned from Mycobacterium smegmatis and Mycobacterium tuberculosis, and expressed in Escherichia coli and M. smegmatis. The induced M. smegmatis NAT catalyzes the acetylation of isoniazid. A monospecific antiserum raised against pure NAT from S. typhimurium recognizes NAT from M. smegmatis and cross-reacts with recombinant NAT from M. tuberculosis. Overexpression of mycobacterial nat genes in E. coli results in predominantly insoluble recombinant protein; however, with M. smegmatis as the host using the vector pACE-1, NAT proteins from M. tuberculosis and M. smegmatis are soluble. M. smegmatis transformants induced to express the M. tuberculosis nat gene in culture demonstrated a threefold higher resistance to isoniazid. We propose that NAT in mycobacteria could have a role in acetylating, and hence inactivating, isoniazid.

Purification, characterization, and crystallization of an N-hydroxyarylamine O-acetyltransferase from Salmonella typhimurium

The N-hydroxyarylamine O-acetyltransferase from Salmonella typhimurium has been expressed as a histidine-tagged fusion protein in Escherichia coli and purified to apparent homogeneity using single-step immobilized metal ion chromatography. Sufficient quantities of the purified protein have been obtained to allow its characterization by physical methods including dynamic light scattering and electrospray mass spectrometry. The substrate specificity and temperature sensitivity of the enzymatic activity have also been assessed. The enzyme has been crystallized from sodium, potassium tartrate and X-ray diffraction data have been obtained to allow the identification of an orthorhombic unit cell, point group P21212, with dimensions a = 137 A, b = 223 A, and c = 105 A. These crystals will provide a route to a crystallographic determination of the structure of the protein.

Application of pattern recognition techniques to mass spectrometric data for sequencing C-terminal peptide residue series

The application of pattern recognition to sequence elucidation from fast atom bombardment (FAB), collisionally activated dissociation (CAD), and tandem mass spectrometric data of peptides was investigated. Learning machine techniques for pattern recognition were applied to detect C-terminal series amino acid sequences up to the pentapeptide Try-Gly-Gly-Phe-Leu (YGGFL). The approach conditions the data by building upon known fragmentation pathways of peptides in FAB/CAD-related analysis. The intensities of critical sequence ion peaks are used to describe each pattern in the training set. A well-defined training set is then made use of to classify unknown species. The FORTRAN-77 program is adapted from one first developed by P.C. Jurs. It requires only the input of the critical peak intensities and the length of the unit to be tested. The method has potential in applications to larger peptides provided a database for the training set can be constructed.