Black Pepper Seeds Research Articles

Somatic embryogenesis and plant regeneration in black pepper (Piper nigrum L.): I. Direct somatic embryogenesis from tissues of germinating seeds and ontogeny of somatic embryos

SummaryA protocol was developed for induction, maturation and germination of somatic embryos from the tissues of germinating seeds of black pepper (Piper nigrum L.). Explants were cultured on growth regulator – free solid SH medium maintained in the dark. The first somatic embryos developing directly from the explant tissue were noticed after 60 d of culture. Somatic embryos originated from a ring-like tissue on the micropylar region of the seeds. Sucrose concentration of the medium was found to be crucial for the induction of somatic embryos, and 30 g l–1 was found to be the optimum. Maturation and germination of somatic embryos were achieved on the same medium. Suspension culture enhanced the process of maturation and germination. Regenerated plants were established in soil. Histology confirmed the ontogeny and each stage of development. Growth regulators were found to inhibit the induction of somatic embryogenesis. Cytological analysis of the regenerated plants revealed the normal chromosome number of 2n=52.

Degradation of the natural mutagenic compound safrole in spices by cooking and irradiation

Safrole was determined using gas-liquid chromatography in some common spices as star anise, cumin, black pepper and ginger. Safrole concentration in these spices was 9,325, 3,432, 955 and 500 mg.kg-1, respectively. Black pepper was chosen to use in the following experiments. Using Ames-test with Salmonella TA 98 and TA 100 proved high cytotoxic effects due to pure safrole and black pepper volatile oil in both of them. The degradation of safrole was obvious after drying of the washed seeds of black pepper especially at 70 degrees C for 30 min or with sun-drying. Also, high irradiation doses (20 and 30 kGy) caused high degradation of more than 90% of the initial toxic concentration in black pepper. Whereas, microwave caused same effects at 75 s, but unfortunately, the powder was burned due to moisture absence. Boiling whole seeds or powder of black pepper during cooking for few minutes (1-5 min) were more efficient in decreasing safrole content. Finally, these results proved that the mutagenicity of some spices due to presence of safrole can be destructed during drying of the washed seeds or during cooking either with or without any additional treatment as irradiation. But irradiation of these species became more necessary for using in some food industries as milk products to get more safe for human consumption.

Mutagenicity and antimutagenicity of extracts of three spices and a medicinal plant in Thailand

Three kinds of spices (caraway, coriander and black pepper seeds) and a medicinal plant called ‘tong tak’ in Thai ( Baliospermum axillar, a species of the spurge family) were fractionated into hot water, methanol and hexane extracts. These extracts were not mutagenic for Salmonella typhimurium strains TA98 and TA100 by the Ames assay. However, when the extracts were treated with nitrite, samples of the water and methanol extracts were mutagenic for strain TA100 without metabolic activation. The mutagenicity of the nitrite-treated methanol and hot water extracts of black pepper was highest (8380 and 22,200 His + per 0.1 g of spice powder, respectively), and that of the nitrite-treated hot water extracts of caraway and tong tak was moderate. The hot water extracts were examined for their antimutagenic activity against mutagenicity induced by various carcinogens by the Ames assay, using the preincubation technique. The tested samples (equivalent to 1–2 mg of spice powder) reduced the mutagenicity induced by 2.7 nmole (397 ng) of N-methyl- N′-nitro- N-nitrosoguanidine by more than 84%, and that induced by dimethylnitrosamine (1.48 mg) or ICR-170 (10 ng) by 30–60%. However, they did not inhibit the mutagenic activity of 1-nitropyrene, 3-nitrofluoranthene, AF-2, methyl methanesulfonate, N-ethyl- N′-nitro- N-nitrosoguanidine, 2-aminoanthracene, 2-acetylaminofluorene, benzo[ a]pyrene or IQ.

Trace Element Analysis of Food Spices by Instrumental Neutron Activation Analysis. I. Trace Elements in Food Spices Belonging to Umbelliferae, Myrtaceae, Piperaceae, Zingiberaceae and Lauraceae Families

Abstract Spices are extensively used in oriental and Latin American cooking and some of these are also used in pharmacy and perfumery. Therefore, concentrations of essential and toxic elements have been measured by instrumental neutron activation analysis (INAA) in seven different spices consumed in the area of Islamabad/Rawalpindi. Cumin and caraway seeds were found to contain relatively high amounts of essential as well as toxic elements. The comparison of our values with Canadian and Egyptian data shows variation in trace element contents of black pepper and cumin seeds. The studies show that these food spices are additional sources of trace element intake.