جستجوی مقالات مرتبط با کلیدواژه « psidium guajava » در نشریات گروه « پزشکی »

Psidium guajava (guava tree) is widely used in Nigeria to treat diseases. However, a paucity of information exists on the safety of the plant. 

This study determined the safety of P. guajava leaves collected in Birnin Kebbi, Nigeria. 

The methanolic extract of the plant’s leaves was subjected to phytochemical and heavy metal screening using standard protocols, and thereafter, subjected to a cytogenetoxicity test using the Allium cepa toxicity assay. Twenty-one A. cepa bulbs divided equally into seven groups were grown over beakers containing distilled water (negative control), formaldehyde (positive control), as well as 0.25, 0.5, 1, 2, and 4 g of the extract, respectively, for five days. The root-tip cells of the A. cepa bulbs were treated and then examined for chromosomal aberrations. 

The phytochemical screening revealed high levels of saponins, and moderate levels of phenols, tannins, and flavonoids, while quinones and terpenoids were sparingly available. The heavy metal analysis showed non-permissible levels of cadmium and zinc, while two other tested heavy metals (lead and copper) were undetected. Except for the A. cepa treated with 0.25 and 0.5 g, the extract induced dose-dependent root growth and mitotic index inhibition (P<0.05). The extract also induced cytogenetic effects, mainly sticky, vagrant, and fragmented chromosomes as well as anaphase bridges. 

It can be inferred from the results that low to medium doses of the extract are safe but may elicit harmful effects at high doses. Advice from a phytomedicine or phytotherapy expert should be sought before using it.

Osteoarthritis is a major public health consideration which leads to disability because of chronic pain, stiffness, sleeping disorder and depression. Among the herbal products Psidium Guajava L. fruit could be regarded as a potential natural remedy due to its anti-oxidant characteristics. The aim of this study was to evaluate the healing effect of Psidium Guajava L. fruit on osteoarthritis of the knee in rats.

Forty male Sprague-Dawley rats with induced osteoarthritis by intra-articular injection of 500U of type 2 collagenase in the left knee were recruited in four treatment groups (n=10): (A) control, (B) Piascledine (10mg/kg) as positive control, (C) oral administration of hydro-alcoholic extract of Psidium Guajava L. fruit (500mg/kg), and (D) oral administration hydro-alcoholic extract of Psidium Guajava L. fruit (1000mg/kg). After 8 weeks of daily administration, the outcome was evaluated by histopathological and radiographic assessments. The data were analyzed using Kruskal-Wallis nonparametric in SPSS version 23.00, and P<0.05 was considered statistically significant.

Psidium Guajava extract exhibited good radical scavenging activities with IC50 of 0.46 ± 0.13 mg/mL (quercetin as a positive control). Histopathological assessments of the cartilage showed smooth and continuous articular surface with columnar cell distribution in the experimental group that received 1000mg/kg Psidium Guajava L. fruit hydro-alcoholic extract which healed better than others, especially in the control group (p-value =0.02). The radiological assessments of the knee joints showed similar findings in histopathological assessment. 

Psidium Guajava L. fruit hydro-alcoholic extract might be regarded as an effective complementary and alternative treatment for osteoarthritis of the knee in rats.

Several plants have been shown to possess antioxidant and estrogenic properties that can be useful in postmenopausal bone-loss prevention. The present study aimed to investigate the anti-osteoporotic effects of the hydroalcoholic extract of the Psidium guajava (PG) fruit in ovariectomized (OVX) rats. Sixty female Sprague–Dawley rats were randomly divided into 6 groups: a control positive group, a sham-operated group, an OVX group given normal saline (OVX-only group), and 3 treatment groups comprising 2 OVX groups treated orally with 500 and 1000 mg/kg/d of the hydroalcoholic extract of the PG fruit respectively and an OVX group treated with an injection of 0.15 mg/kg of estradiol. The study was conducted over a 12-week period. Samples from the animals’ blood, femoral bones, and uteri were collected for stereological and biochemical analyses. The data were analyzed using SPSS, version 19. A P value equal to or less than 0.05 was considered statistically significant. The results revealed a significant decrease in the levels of calcium, total antioxidant capacity, and phosphorus as well as uterus weight, femoral ash density, femoral volume and weight, and numbers of osteocytes and osteoblasts. Moreover, there was an increase in the levels of alkaline phosphatase and urine deoxypyridinoline together with a rise in the number of osteoclasts in the OVX-only group compared to the control and treatment groups (P≤0.05). The hydroalcoholic extract of the PG fruit increased femoral weight and volume, femoral ash density, numbers of osteocytes and osteoblasts, and trabecular volume of the bones in comparison with the OVX-only group in a dose-dependent manner. No significant difference was observed between the groups in the levels of malondialdehyde and interleukin-6. The hydroalcoholic extract of the PG fruit prevented OVX-induced bone loss in the rats, with no proliferative effect on atrophic uteri; it should, therefore, be considered for treatment purposes.

The aim of this in vitro study was to assess antimicrobial efficacy of Acacia nilotica, Murraya koenigii (L.) Sprengel, Eucalyptus hybrid, Psidium guajava extracts, and their combination on Streptococcus mutans and Lactobacillus acidophilus.
The branches of four plants were collected, identified, and authenticated by a taxonomist. The plants were rinsed in water, healthy leaves were separated and shade dried over a period of 3–4 weeks. Soxhlet apparatus using ethanol was employed for extraction procedure. The combinations of plant extracts were prepared by mixing equal quantities of 10% solutions of each of these extracts. 0.2% chlorhexidine and dimethyl sulfoxide were used as positive and negative controls, respectively. The antimicrobial efficacy testing was done using agar well‑diffusion method under anaerobic conditions. The mean diameter of inhibition zone was computed and compared between different categories using one‑way analysis of variance and Tukey’s post‑hoc test. A qualitative assay was carried out to identify the various phytochemical constituents in the plants. The data was assessed by SPSS version 20. The statistical significance was fixed at 0.05.
All the plants extracts and their combinations inhibited S. mutans and L. acidophilus. However, the quadruple combination of A. nilotica M. koenigii (L.) Sprengel Eucalyptus hybrid P. guajava produced the maximum inhibition zone (23.5 ± 2.2 mm) against S. mutans. Although, 0.2% chlorhexidine produced the highest inhibition zone against L. acidophilus (18.8 ± 1.2 mm), A. nilotica extract produced maximum inhibition among the various plant extracts and their combinations (14.1 ± 1.8 mm).
All the individual plant extracts and their combinations were effective against S. mutans and L. acidophilus. These could be tried as herbal alternates to chlorhexidine. However, these in vitro results have to be further evaluated for any toxicity of the polyherbal combinations in animal models and effectiveness has to be assessed using in vivo studies on humans.