Search

Capsicum chinense Jacq. (ghost pepper), a naturally occurring chili species of Northeast India is known throughout the world for its high pungency and a pleasant aroma. The economic importance is due to the high capsaicinoid levels, the main source for pharmaceutical industries. The present study focused on identifying important traits necessary for increasing the yield and pungency of ghost pepper and to determine the parameters for the selection of superior genotypes. A total of 120 genotypes with more than 1.2% capsaicin content (>1,92,000 Scoville Heat Unit, w/w on dry weight basis) collected from different northeast Indian regions were subjected to variability, divergence and correlation studies. Levene's homogeneity test of variance studied for three environments did not show significant deviation and so homogeneity of variance was reasonably met for analysis of variance study. Genotypic and phenotypic coefficient of variation was highest for fruit yield per plant (33.702, 36.200, respectively), followed by number of fruits per plant (29.583, 33.014, respectively) and capsaicin content (25.283, 26.362, respectively). The trait number of fruits per plant had maximum direct contribution to fruit yield per plant and the trait fruit yield per plant towards capsaicin content in the correlation study. High heritability with high genetic advance, which is the most favored selection criteria was observed for fruit yield per plant, number of fruits per plant, capsaicin content, fruit length and fruit girth. The genetic divergence study partitioned the genotypes into 20 clusters, where fruit yield per plant contributed maximum towards total divergence. Principal components analysis (PCA) studied to determine the largest contributor of variation showed 73.48% of the total variability, of which the PC1 and PC2 contributed 34.59% and 16.81% respectively., Competing Interests: Mohan Lal is an Academic Editor for PeerJ., (©2023 Baruah et al.)

Background: Kaempferia galanga (L.) is one of the prospective therapeutic plants with an aromatic rhizome, and belongs to the Zingiberaceae family. This herb is commonly used by local practitioners in traditional Asian medicine., Methods: In the present investigation, the novel Kaempferia galanga rhizome essential oil rich in ethyl p-methoxy cinnamate (EMCKG) was evaluated using GC/MS for chemical composition analysis. EMCKG was analyzed for its possible antimicrobial, neurodegenerative inhibitory, acetylcholinesterase, anti-inflammatory, and antioxidant activities as well as for the genotoxic effects using the standard methodologies. ANOVA and post hoc was performed to test the statistical significance of the study., Results: GC/MS analysis identified ethyl p-methoxy cinnamate as the major component of EMCKG essential oil with an area percentage of 66.39%. The EMCKG exhibited moderate (DPPH assay IC 50 = 15.64 ± 0.263 µg/mL; ABTS assay IC 50 = 16.93 ± 0.228 µg/mL) antioxidant activity than standard ascorbic acid (DPPH assay IC 50 = 21.24 ± 0.413 µg/mL; ABTS assay IC 50 = 21.156 ± 0.345 µg/mL). Similarly, EMCKG showed comparable activity in albumin denaturation (IC 50 = 2.93 ± 0.59 µg/mL) and protease inhibitor assay (IC 50 = 17.143 ± 0.506 µg/mL) to that of standard sodium diclofenac (IC 50 = 23.87 ± 0.729 µg/mL and IC 50 = 19.18 ± 0.271 µg/mL, respectively). The EMCKG exhibited a dose-dependent antimicrobial activity pattern with the highest inhibitory activity at 500 µg/mL against Staphylococcus aureus and considerable anticholinesterase activities (IC 50 = 21.94 ± 0.109 µg/mL) compared to the standard galanthamine (IC 50 = 27.18 ± 0.511 µg/mL). EMCKG also showed strong anti-diabetic activity (IC 50 = 18.503 ± 0.480 µg/mL) and anti-tyrosinase activity (IC 50 = 14.756 ± 0.325 µg/mL) as compared to the standards used (acarbose IC 50 = 20.39 ± 0.231 µg/mL and kojic acid IC 50 = 17.73 ± 0.192 µg/mL) in the study. Genotoxicity analysis of EMCKG revealed that at 1 µg/mL concentration has no toxic effects in mitosis of Allium cepa roots (Mitotic Index MI = 13.56% and chromosomal aberration CA = 07.60%). The ANOVA confirmed that except for the anticholinesterase activity, there is insignificant difference for essential oil and standards used for all the other bioactivities thus confirming their interchangeable applicability., Conclusions: Current research provides the basis for the fact that besides being a rich source of ethyl p-methoxycinnamate, EMCKG has the potential for future formulation and development of an inexpensive skin-care agent and for the preparation of anti-diabetic drugs., Competing Interests: The authors declare that they have no competing interests., (© 2023 Begum et al.)