Volatile fraction of neem oil as a spermicide

Screening essential oils for their antimicrobial activities against the foodborne pathogenic bacteria Escherichia coli and Staphylococcus aureus

The application of essential oils as antimicrobials is a current subject of research and a promising approach in terms of natural food preservation. Due to the diversity of EO producing plant genera and the inconsistent use of susceptibility testing methods, information on the antibacterial potency of many EO varieties is fragmentary. This study was performed to assess the minimal inhibitory concentrations (MIC) of 179 EO samples from 86 plant varieties, using a single method approach, excluding emulsifying agents. MICs were acquired in a broth microdilution assay, using a dispersion based approach to incorporate EOs in a concentration range of 6400 to 50 μg/ml. Staphylococcus aureus and Escherichia coli were used as model bacteria. At concentrations below 400 μg/ml S. aureus was inhibited by 30, E. coli by 12 EO varieties. Azadirachta indica (50 μg/ml vs. S. aureus) and Litsea cubeba (50 μg/ml vs. S. aureus, 200 μg/ml vs. E. coli) essential oils were identified as promising new antimicrobial EO candidates with significant antimicrobial activity against the two foodborne pathogenic bacteria.

Effect of the essential oil of Rosmarinus officinalis (L.) on rooster sperm motility during 4°C short-term storage

AIM

This study aimed to investigate the protective effect of Rosmarinus officinalis (L.) essential oil on rooster sperm motility during 4°C short-term storage.

MATERIALS AND METHODS

R. officinalis essential oil was analyzed using gas chromatography coupled to mass spectrometry to identify the active components. 10 of 45-week-old Hubbard commercial broilers were subjected to biweekly semen collections during 3 weeks. At each collection, sperm was pooled and divided into four aliquots and then diluted with Tris extender supplemented with 870, 87, or 8.7 µg/ml of R. officinalis essential oil, identified as treatments R, R5, and R10, respectively. Tris-based extender without any supplementation was considered as a control group. Diluted sperm was then stored at 4°C in the refrigerator and analyzed at 0, 6, 24, and 48 h using a computer-assisted sperm analyzer. Different semen parameters were measured including total motility, progressive motility, gametes velocities (straight line velocity [VSL], curvilinear velocity [VCL], and average path velocity [VAP]), amplitude of the lateral head displacement [ALH], and beat-cross frequency [BCF].

RESULTS

The phytochemical analysis of R. officinalis essential oil revealed the presence of 25 active components including seven major molecules: Camphor (18.88%), camphene (5.17%), 1,8-cineole (7.85%), β-thujene (13.66%), α-thujene (4.87%), chrysanthenone (12.05%), and β-cubenene (7.97%). The results showed a beneficial effect of R. officinalis essential oil on sperm cells motility, particularly when using the lowest concentrations, 8.7 and 87 µg/ml. Progressive motility and gametes velocities (VCL, VSL, and VAP), materializing the quality of gametes motility, showed highly statistically significant values (p<0.01) in 8.7 and 87 µg/ml treatments, especially from 6 h of storage at 4°C. Conversely, the highest concentration (870 µg/ml) showed harmful effects with a total spermicidal activity after 24 h of storage.

CONCLUSION

The current results revealed the positive impact of R. officinalis essential oil on rooster sperm at 4°C short-term storage probably through fighting against oxidative stress and cold shock damages.

Azadirachta indica treatment on the congenital malformations of fetuses from rats

ETHNOPHARMACOLOGICAL RELEVANCE

Azadirachta indica A. Juss, popularly known as neem, presents medicinal and insecticide properties. However, the repercussions of the neem maternal treatment on fetal development should be investigated. Thus, the aim of this study was to evaluated the effects of Azadirachta indica (neem) on the frequency of congenital malformations in fetuses from rats.

MATERIALS AND METHODS

Pregnant rats were randomly distributed into three experimental groups: NT=non-treated; TOil=treated with neem seed oil (1.2 mL/day); TAP=treated with active principle of Azadirachta indica (azadirachtin-1.0 mg/mL/day). The neem oil (1.2 mL/day) or azadirachtin (1.0 mg/mL/day) treatments were orally administered throughout pregnancy. Blood samples were collected on days 0, 7, 14 and 20 of pregnancy. Oral glucose test tolerance (OGTT) was performed at day 17 of pregnancy for estimation of total area under the curve (AUC). At term, the fetuses were collected and external and internal (visceral and skeletal) malformations were analyzed.

RESULTS

The data showed that the dams treated with neem seed oil and Azadirachtin had no significant change in glucose levels and AUC. It was also verified that neem oil treatment contributed to increase the frequency of malformation/variation, in particular the visceral in their fetuses, while neither significant result was observed in TAP group.

CONCLUSION

In conclusion, neem seed oil treatment administered during pregnancy caused abnormalities in rat fetuses, showing teratogenic effect but the Azadirachtin (active principle) presented no impairment in the fetuses.

Review on pharmacological and toxicologyical effects of oleum azadirachti oil

Oleum azadirachti consists of the oil obtained from dried seeds of Azadirachta indica A. Juss. (family: Meliaceae). Local names of Azadirachta indica A. Juss. are Abodua, aforo-oyinbo, anwe egyane, arista, azad dirakht, azadarakht, azedarach and bead tree. Indigenous to India, and widely distributed in South and South-East Asia and cultivated in Africa, the South Pacific Islands, South and Central America and Australia, and in southern Florida and California, United States of America, it is a straight-boled deciduous tree, which is 6-25 m high. Bark is dark-brown, externally fissured with a buff inner surface and fibrous fracture. Leaves alternately arranged, pinnately compound and up to 40 cm long, and composed of 8-18 short-petiolate narrow-ovate, pointed and curved toothed leaflets, 3-10 cm long and 1-4 cm wide arranged in alternate pairs. The major constituents are oxidized tetranortriterpenes including azadirachtin (azadirachtin A), azadiriadione, epoxyazadiradione, azadirone, nimbidin, nimbin, deacetylnimbin, salannin, gedunin, mahmoodin, 17-hydroxydiradione and related derivatives. It is of various medicinal uses, such as a contraceptive for intravaginal use, a mosquito repellent, and treatment of vaginal infections, treatment of gastric ulcers, cardiovascular disease, malaria, rheumatism and skin disorders, external applications for treatment of septic wounds, ulcers and boils, treatment of allergic skin reactions, asthma, bruises, colic, conjunctivitis, dysmenorrhoea, fever, gout, headache, itching due to varicella, kidney stones, leukorrhoea, psoriasis, scabies, sprains and muscular pain, and wounds. It is also used as an emmenagogue, tonic, stomatic and vermicide. In conclusion, the plant oil had antifertility, antihyperglycaemic, anti-inflammatory, antimicrobial, antiviral, antiulcer, estrogenic, immune, contraceptive, antibacterial, insect repellent, and skin treatment effects.

Spermicidal activity of Indian seaweeds: an in vitro study

Contraceptive properties of seaweeds are still stands as lacuna; in this context, the screening of in vitro male contraceptive properties of crude ethanolic extract of Indian seaweeds against normal human sperm is carried out. In total, twelve seaweeds were screened for in vitro spermicidal activity. Among these twelve seaweeds, Halimeda gracilis showed 100% inhibition of human spermatozoa at 10 mg ml(-1) concentration in 20 s and its EC50 value was 2.05 mg ml(-1) in 20 s. Further, dose- and time-dependent spermicidal assay revealed that the sperm was completely immobilised for 20 s. Plasma membrane of sperm was damaged due to the exposure of H. gracilis extract. MTT assay with H. gracilis extract showed 88.5% of cytotoxic incidence. H. gracilis extract tested for cytotoxicity against Artemia salina recorded LC50 value of 34.8 μg ml(-1) . Phytochemical analysis of H. gracilis extract evidenced the presence of alkaloids, flavonoids, proteins and sugars. Results of this study clearly inferred that the synergistic effect of active principles reside within the H. gracilis extract had shown better contraceptive activity.

Identification of a sulfonoquinovosyldiacylglyceride from Azadirachta indica and studies on its cytotoxic activity and DNA binding properties

Chromatographic separation of the methanolic extract of the leaves of Azadirachta indica led to the isolation of a sulfonoglycolipid characterized as a sulfonoquinovosyldiacylglyceride (SQDG), by extensive 2D NMR and mass spectral analysis. SQDG induces apoptosis in a dose dependent manner with IC(50) 8.3 μM against acute lymphoblastic leukemia (ALL) MOLT-4 cell lines. The compound showed significant DNA binding properties as evidenced by the enhancement of melting temperature and perturbation of the characteristic B-form in CD evidence of calf thymus DNA. The DNA binding was also characterized by isothermal calorimetry where a predominantly enthalpy driven binding to CT DNA was revealed.

Isolation and identification of the antibacterial active compound from petroleum ether extract of neem oil

From a petroleum ether extract of neem oil (Azadirachta indica A. Juss) the new tetrahydrofuranyl diester 1 was isolated as an anti-bacterial constituent. 1 showed significant activities against three standard bacterial strains, including Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922 and Salmonella enteritidis CMCC (B) 50041.

Contraceptions masculines non déférentielles : revue de la littérature

OBJECTIVES

To review the state of progress of the various male contraceptive methods (with the exception of deferential methods).

MATERIAL AND METHODS

A review of the literature was performed by using the key words: male/contraception, limiting the search to original articles in English and French. Articles on vasectomy and the other deferential methods of contraception are not considered in the present review.

RESULTS

Three methods of male contraception are widely used at the present time: withdrawal, male condom and vasectomy, although other types of male contraception have been shown to be effective, including hormonal contraception, which appears to be the most promising technique and the subject of the majority of research. Other contraceptive methods (immunological, thermal...) could constitute possible alternatives.

CONCLUSION

Male contraception remains under-used, as only male condoms are commonly used (apart from withdrawal and vasectomy). Consequently, new research protocols in the field of male contraception must be strongly encouraged.

Lack of toxic effect of technical azadirachtin during postnatal development of rats

Azadirachtin, a biopesticide has been evaluated for its possible toxic effects during postnatal development of rats over two generations. Rats were fed 100, 500 and 1000ppm technical azadirachtin through diet which is equivalent to 5, 25 and 50mg/kg body weight of rats. Technical azadirachtin has not produced any adverse effects on reproductive function and data were comparable to control animals over two generations. There were no toxicological effect in parent rats as evidenced by clinical signs of toxicity, enzymatic parameters like AST, ALT, ALP, S. bilirubin, S. cholesterol, total protein and histopathology of liver, brain, kidney and testes/ovary. The litters of F(1B) and F(2B) generations were devoid of any morphological, visceral and teratological changes. The percent cumulative loss and growth index of pups were also comparable to respective controls in successive growth period of 0, 4, 7, 14 and 21 days in two generations. There were no major malformations in fetuses while some insignificant minor skeletal variations like missing 5th sternebrae and bipartite thoracic centre found were not compound or dose related. No significant pathomorphological changes were observed in liver, kidney, brain and gonads of F(2B) pups. In conclusion rats fed technical azadirachtin showed no evidence of cumulative effects on postnatal development and reproductive performance over two generations. Absence of any major adverse reproductive effects in adults as well as in 21 days old pups of F(2B) generation suggest the safe use of technical azadirachtin as a biopesticide.

Neem-An Omnipotent Plant: A Retrospection

Neem (Azadirachta indica A. Juss.) has universally been accepted as a wonder tree because of its diverse utility. Multidirectional therapeutic uses of neem have been known in India since the Vedic times. Besides its therapeutic efficacies, neem has already established its potential as a source of naturally occurring insecticide, pesticide and agrochemicals. Safe and economically cheaper uses of different parts of neem in the treatment of various diseases and in agriculture are discussed in this article. It further deals with the active chemical constituents of various neem formulations. Commercially available neem products are also mentioned along with their respective applications. Furthermore, evaluation of safety aspects of different parts of neem and neem compounds along with commercial formulations are also taken into consideration. Systematic scientific knowledge on neem reported so far is thus very useful for the wider interests of the world community.

Spermicidal activity of Azadirachta indica (neem) leaf extract

The present study was carried out to evaluate the effective concentration of aqueous extract of old and tender Azadirachta indica (neem) leaves to immobilize and kill 100% human spermatozoa within 20 s. Sander-Cramer test was used to study the spermicidal activity of neem leaf extract. Under the test conditions, minimum effective spermicidal concentrations for tender and old leaf extracts were 2.91 +/- 0.669 mg/million sperm and 2.75 +/- 0.754 mg/million sperm, respectively. The effect of extracts on morphology and viability of sperm was also studied and no change was observed in morphology of head, mid-piece and tail and no viable sperm seen. The leaf extracts were found to be water soluble and carbohydrate in nature. The effect of different concentrations of extracts (old and tender) on percentage motility of the sperm was also studied. With an increase in concentration, there is a linear decrease in percentage motility, becoming zero at a 3-mg dose within 20 s.

Spermicidal activity of the crude ethanol extract of Sedum praealtum in mice

Ethanol extract of Sedum praealtum in intravaginal doses of 10, 20, 40, 50, 100 and 150 mg/kg body weight showed a toxic effect in spermatozoa viability after 24h of administration. Spermatozoa viability was 94, 83, 58 and 24%, respectively, for extract doses of 10, 20, 40 and 50mg/kg body weight, while only dead spermatozoa were found in the vagina of the treated female mice with doses of 100 and 150 mg/kg body weight.

Spermicidal activity of seed oil of Pongamia glabra

The medicinal properties of seed oil of Pongamia glabra are well known in traditional Indian medicine. It has antimicrobial activity against several organisms. It is used in the treatment of herpes and scabies and, systemically, it is also used in the treatment of dyspepsia with sluggish liver. The present study demonstrates that in vitro, Pongamia oil has strong spermicidal activity.

Current status of fertility control methods in India

Approximately 48.2% of couples of 15 to 49 years of age practice family planning methods in India. Female sterilization accounts for 34.2%, with male sterilization declining from 3.4% in 1992-93 to 1.9% in 1998-99. Use of the condom increased to 3.1% from 2.4%. There is an urgent need for research to develop new contraceptive modalities especially for men and also for women and to make existing methods more safe, affordable and acceptable. Current efforts in India to develop a male contraceptive are mainly directed towards (i) development of antispermatogenic agents to suppress sperm production, (ii) prevention of sperm maturation, (iii) prevention of sperm transport through vas deferens or rendering these sperm infertile and (iv) prevention of sperm deposition. Research work in the field of prevention of sperm transport through vas deferens has made significant advances. Styrene maleic anhydride (SMA) disturbed the electrical charge of spermatozoa leading to acrosome rupture and consequent loss in fertilizing ability of sperm. A multicentre phase-III clinical trial using SMA is continuing and it is hoped that the SMA approach would be available in the near future as an indigenously developed injectable intra-vasal male contraceptive. The safety and efficacy of available oral contraceptives were evaluated. An indigenously developed oral contraceptive 'Centchorman', which is a nonsteroidal, weakly estrogenic but potently antiestrogenic, was found to be safe and effective and is now being marketed in India since 1991 as a 'once a week' pill. Cyclofem and Mesigyna have been recommended as injectable contraceptives with proper counselling and service delivery by Indian studies. It has been recommended that these injectable contraceptives be added to the existing range of contraceptive methods available in the National Family Planning Programme. Based on the Indian studies CuT 200 was also recommended. Studies have indicated the advantage of intrauterine devices (IUD); they are long acting, relatively easily removed and fertility returns rapidly after their removal. Recent studies have recommended CuT 200 for use up to 5 years. The combination of some plant products i.e. Embelia ribes, Borax and Piper longum has been found to be safe and effective as a female contraceptive and the results of phase-I clinical trials are encouraging. Research work is going on in the country in various areas with special reference to hormonal contraceptive - a three monthly injectable contraceptive, immuno-contraceptives, antiprogestins, etc.

Anti-microbial activity of a new vaginal contraceptive NIM-76 from neem oil (Azadirachta indica)

Efficacy of NIM-76, a spermicidal fraction from neem oil, was investigated for its antimicrobial action against certain bacteria, fungi and Polio virus as compared to whole neem oil. The NIM-76 preparation showed stronger anti-microbial activity than the whole neem oil. It inhibited growth of various pathogens tested including Escherichia coli and Kleibsiella pneumoniae which were not affected by the whole neem oil. NIM-76 also exhibited antifungal activity against Candida albicans and antiviral activity against Polio virus replication in vero cell lines. It also protected mice from systemic candidiasis as revealed by enhanced % survival and reduced colony forming units of C. albicans in various tissues. This shows that NIM-76 has a potent broad spectrum anti-microbial activity.

Early post implantation contraceptive effects of a purified fraction of neem (Azadirachta indica) seeds, given orally in rats: possible mechanisms involved

Neem seed and leaf extracts have immunomodulators that induce cellular immune reactions. These aspects of neem were exploited in earlier studies, where the oral administration of the neem seed extracts in rodents and primates could completely abrogate pregnancy at an early post implantation stage. Complete restoration of fertility was observed in the animals treated in the subsequent cycles. For the purpose of using neem as a long term contraceptive, an activity guided fractionation, followed by identification and characterization of the biologically active fraction from neem seeds was carried out. Sequentially extracted fractions of neem seeds were tested orally at an early post implantation stage in rats. The hexane extract of the neem seeds was found to be biologically active and was the precursor for the final active fraction. The active fraction, identified as a mixture of six components, could completely abrogate pregnancy in rodents up to a concentration of 10%. No apparent toxic effects could be seen following treatment with the fraction. The treatment with the active fraction caused a specific activation of T lymphocyte cells of CD8+ subtype as well as phagocytic cells followed by elevation in cytokines gamma-interferon and TNF. The results of the present study show that a pure active fraction of neem seeds could be obtained for the purpose of early post implantation contraception when given orally, and its mechanism of action seems to be by activating cell mediated immune reactions.

Immunomodulatory effects of NIM-76, a volatile fraction from Neem oil

The immunomodulatory properties of NIM-76 have been described in this paper. Pre-treatment of rats with a single i.p. injection of NIM-76 resulted in an increase in polymorphonuclear (PMN) leukocytes with a concomitant decrease in lymphocyte counts. The immunomodulatory activity of NIM-76 was found to be concentration-dependent. At 120 mg/kg body weight, there was an enhanced macrophage activity and lymphocyte proliferation response, while the humoral component of immunity was unaffected. At higher concentrations of NIM-76 (300 mg/kg body weight), there was a stimulation of mitogen-induced lymphocyte proliferation, while macrophage activity remained unaffected. However, a fall in primary and secondary antibody titres was observed. The study indicates that NIM-76 acts through cell-mediated mechanisms by activating macrophages and lymphocytes.

Mechanism of action of NIM-76: a novel vaginal contraceptive from neem oil

The present study was undertaken to elucidate the mechanism of spermicidal action of NIM-76, a fraction isolated from neem oil. The spermicidal activity of NIM-76 was confirmed using a fluorescent staining technique. NIM-76 was found to affect the motility of the sperm in a dose-dependent manner. Supplementation of pentoxifylline, which is known to enhance the motility of the sperm, could not prevent the spermicidal action of NIM-76. There was a gradual leakage of cytosolic LDH from the sperm in the presence of NIM-76. Electron microscopic studies revealed the formation of pores and vesicles over the sperm head, indicating the damage to the cell membrane. Membrane fluidization studies did not reveal any significant change in the fluidity of sperm cell membrane structure.

Termination of pregnancy in rodents by oral administration of praneem, a purified neem seed extract

PROBLEM

Development of an orally administered abortifacient.

METHODS

Subjects were female Wistar rats, weighing 150 to 200 g at the time of experiments. Praneem (a purified extract of neem Azadirachta indica) at a dose of 0.6 ml was given orally from day 8 to 10 after confirming presence and number of implants surgically on day 7 of pregnancy. The animals were examined again under anesthesia on day 15 of pregnancy to check the number of developing embryos. Controls received an equivalent regime of peanut oil. The number and size of implants were counted five days after treatment.

RESULTS

Complete resorption of embryos was observed on day 15 of pregnancy in every animal treated with Praneem in contrast to normally developing embryos in rats given peanut oil. In repeat batch experiments, it was established that the effect of the treatment was reversible and animals regained fertility in cycles subsequent to treatment with Praneem. Cytokines of Th1 type, i.e., gamma interferon and TNF, were raised on administration of Praneem, which may be the probable cause of pregnancy termination.

CONCLUSIONS

Praneem on oral administration can cause termination of pregnancy in rodents, and the action is probably mediated by TH1 cytokines.

Mode of long-term antifertility effect of intrauterine neem treatment (IUNT)

The mode of antifertility action of intrauterine neem treatment (IUNT) was studied. The effect of IUNT on ovarian functions and uterine responsiveness to ovarian hormones was examined in adult Wistar rats. The treated animals had normal reproductive cycles as indicated by the vaginal smears; serum progesterone levels were also in the normal range. Effect of exogenous estradiol following IUNT in ovariectomized rats showed comparable uterine weight gain as in control group; decidual cell reaction of the uterine epithelium following IUNT was also similar to that of control, indicating normal uterine responsiveness to ovarian hormones. Unilateral IUNT followed by mating resulted in degeneration of embryos on the treated side as noted between days 3-5 post coitum; normal embryos were seen on the contralateral side given peanut oil. The study shows that the mode of antifertility action of IUNT is not because of uterine unresponsiveness to the ovarian hormones but is due to impairment of embryo development. The results of this study thus confirm our earlier observations and show further that the antifertility effect of IUNT is at the pre-implantation stage, localized and without any adverse or toxic effect on the fetal development in the contralateral uterine horn of the unilaterally treated rats. The exact mechanism(s) of antifertility action of IUNT is being investigated.

Neem oil inhibits two-cell embryo development and trophectoderm attachment and proliferation in vitro

PURPOSE

The in vitro effect of neem oil was studied on the development of mouse two-cell embryos and trophectodermal cell attachment and proliferation.

METHOD

Female mice were primed with gonadotropins for superovulation and caged with male mice. Early embryos, at the two-cell and the blastocyst stages, were recovered at 40 and 88 hr post-hCG from the oviducts and the uteri, respectively. In the first experiment, two-cell embryos were exposed to culture medium containing different concentrations of neem oil for 1, 12, and 24 hr and then grown in neem oil-free culture medium and assessed for the formation of total and hatching blastocysts at 96 hr. In the second experiment, partially hatching blastocysts were cocultured with human endometrial stromal cell monolayers in culture medium containing different concentrations of neem oil and assessed for the attachment and proliferation of trophectodermal cells at 96 hr.

RESULTS

Exposure of two-cell embryos to neem oil concentrations of 0.050-0.500% for 1 hr, 0.010-0.250% for 12 hr, and 0.005-0.100% for 24 hr caused significant inhibition of the formation of total and hatching blastocysts, in a dose-dependent manner. Neem oil at 0.050-0.100% concentrations inhibited, in a dose-dependent manner, the in vitro attachment and proliferation of trophectodermal cells of partially hatching blastocysts cocultured with human endometrial stromal cells monolayers.

CONCLUSION

Neem oil inhibits the development of two-cell embryos and attachment and proliferation of the trophectodermal cells of partially hatching blastocysts in vitro. The study encourages the use of this herbal product as a postcoital contraceptive that warrants further research.

Synergistic spermicidal activity of neem seed extract, reetha saponins and quinine hydrochloride

In order to identify potent spermicidal agents which are free from the side effects of currently available agents, spermicidal activity of purified neem seeds extract (Praneem), reetha saponins and quinine hydrochloride was studied individually and in combination. Sander-Cramer test was used to assess the activity on human sperm. Under the test conditions, minimum effective spermicidal concentrations for Praneem, reetha saponins and quinine hydrochloride were 25%, 0.05% and 0.346%, respectively. At these concentrations, 100% of the sperm were immobilised within 20 seconds. A positive synergistic effect in the spermicidal activity of these components, if used in combination, was observed which implies the use of reduced concentrations of each to bring about the desired action. The selected combination formulated into a suitable dosage form is likely to offer dual benefit of a potent contraceptive and an antimicrobial preparation.

Antifertility activity of volatile fraction of neem oil

NIM-76, the odorous and volatile fraction of neem oil, was investigated for its antifertility activity in vivo in rats, rabbits and rhesus monkeys. The drug is effective when applied before coitus but not so when applied during post-coital stages. It, therefore, appears to act mainly by its spermicidal effect. No alteration in the estradiol (E2) and progesterone (P) values was observed after the application of the drug in monkeys.