Aside from being a significant source of highly nutritious and medicinally valuable mushrooms, mushroom cultivation is an important means of environmental remediation. Oyster mushroom (Pleurotus ostreatus) is a versatile mushroom that can be grown in various environmental conditions and non-composted lignocellulosic wastes. The present study was conducted to assess the growth response of oyster mushroom on sesame stalk. Spawn was prepared from a mycelium culture grown on potato dextrose agar. The spawn was inoculated onto sesame stalk and wheat straw substrates and incubated at room temperature in the dark for 21 days. A Completely Randomized Design (CRD) was used with five treatments, including the control (100% wheat straw), which were triplicated. Data was analyzed using Minitab version 19. Significant (P < 0.05) differences in days taken for mycelial colonization, primordial appearance, maturity and yield was observed between the substrate formulations. 100% SS (100% sesame stalk) was fastest (19.00 days) in mycelial colonization period but statistically parity with 75% SS + 25% WS (75% sesame stalk + 25% wheat straw). 75% SS + 25% WS (75% sesame stalk + 25% wheat straw) was faster (3.33 days) for primordial appearance while 100% SS(100% sesame stalk) was faster (6.67 days) in maturity. The highest yield (1850 g) and biological efficiency (185%) was recorded by 100% SS (100% sesame stalk). Pearson’s correlation showed that cap diameter and stipe length directly correlate yield and biological efficiency and faster substrate colonization leads to quicker maturation. The current study suggests that sesame stalk can be an alternative substrate for cultivation of oyster mushrooms.

Probiotic foods have evolved from traditional fermented products to scientifically validated functional foods, defined by the FAO and WHO as live microorganism that confer a health benefit on the host when administered in adequate amounts, with effects being strain, does and end point specific. Initially dominated by dairy‐based products, the growing prevalence of lactose intolerance and environmental concerns has spurred innovation in non‐dairy probiotic alternatives, including fruit juices, cereals, and plant‐based matrices. Probiotics exhibit diverse health‐promoting mechanisms, such as competitive exclusion of pathogens, production of antimicrobial compounds, and enhancement of nutrient bioavailability. Recent advancements in biotechnology, including CRISPR‐engineered strains, microencapsulation, omics technologies, and AI‐driven optimization, are the potential of applications probiotic applications, enabling more precise strain selection and improved viability. While some of these technologies are at the proof of concept stage, their future translation to the food market will require navigating regulatory pathways and addressing consumer acceptance. Beyond health benefits, probiotic foods contribute to sustainable food security by reducing food waste, enhancing nutritional value, and supporting circular economy models through waste upcycling and lower environmental impact. However, challenges such as strain viability, regulatory harmonization, and scalability in developing countries like Ethiopia's Tigray, where indigenous fermented foods remain understudied, must be addressed. This review highlights the latest advancements in probiotic foods, emphasizing their role in sustainable food security through waste reduction, nutritional enhancement, and eco‐friendly production.

Nowadays, the inoculation of plant growth-promoting rhizobia in leguminous and nonleguminous crops is given great emphasis as it improves germination and seedling vigor, resulting in increased yields. In this study, 32 rhizobia isolates were obtained from five different sampling sites in Tigray, Ethiopia. Based on morphological, biochemical, and confirmatory tests, including sugar fermentation, the isolates were identified as belonging to the rhizobia genera. In vitro assessment of plant growth-promoting properties revealed that all isolates produced indole-acetic-acid, ammonia, and solubilized phosphate, except TA8, which did not solubilize phosphate. Only 3 isolates (TA1, TA2, and TA8) produced hydrogen cyanide, so they can be used as biocontrol agents. Nineteen isolates showed a growth reduction activity against Fusarium oxysporum, with a percent inhibition range of 34.2%–65.8%. All isolates tolerated a pH range of 4.0–9.0. The isolates showed growth variations in various temperatures and salt concentrations. A few isolates were tolerant up to 45°C temperature and 6% (w/v) CaCl₂ and NaCl concentrations. Inoculation of the isolates to wheat seeds increased seed germination, seedling shoot/root length, and seedling vigor index compared to the positive and negative controls. Isolates KO3, KO4, ME3, and TA5 increased seed germination by 4%. KO1 (11.60 cm) and TA7 (11.70 cm) showed a significantly enhanced shoot length, and ME3 showed a maximum root length (13.90 cm). SH1, KO2, and the positive control showed a significant ( ) increase in pea seed germination (by 20%) compared to the negative control. The positive control had the longest field pea shoot (5.70 cm), and isolate TA9 had the longest field pea root (5.32 cm) compared to the negative control. Generally, the wheat and field pea seedlings responded differently to the inoculation of different isolates. This study shows that Tigray soils harbor a variety of rhizobia species, which can be used as plant growth-promoting and biocontrol agents.

Different commercially available culture media have been in use for the isolation and identification of microorganisms for many years. However, the high cost and limited availability culture media has been a problem in the local market of Tigray, Ethiopia that hinder researchers from carrying out their study. Therefore, the present study aimed to develop locally available cheap plant-based culture medium from cactus pear (Opuntia ficus-indica) cladodes extract for the growth of Lactobacillus species. For this purpose, free external injuries of cactus pear cladode samples were collected from the vicinity of Adigrat, Tigray, Ethiopia. For the test two Lactobacillus species (Lactobacillus reuteri and Lactobacillus mali) were used. The growth of Lactobacillus species on cactus pear cladode agar and broth (4:100, 4:200 and 4:300 w/v) were evaluated and compared with de Man, Rogosa, and Sharpe (MRS) medium. All prepared cactus pear cladode agar (CPCA) media were transparent and free from particles and turbidity. Both tested Lactobacillus species were produced small, white and round colonies on CPCA at 72 hours without bad odor and any pigments. Exponential growth was observed in cactus pear cladode broth (4:200 w/v) in short time than other cactus pear cladode broth (4:100 and 4:300 w/v) medium. When compared with MRS medium (control), the colony counts of Lactobacillus species in cactus pear cladode broth (4:200 w/v) medium did not differ significantly (P < 0.05). The present study clearly showed that the cactus pear cladode (4:200 w/v) medium could be used as alternative culture medium to support growth of Lactobacillus species.

In Tigray, Ethiopia, the mushroom-growing industry is new and has been introduced as an alternative to ensure sustainable food and nutrition security and create employment opportunities. The culture medium used for the growth of mushroom tissue culture and spawn preparation generally uses potato dextrose agar (PDA) media, but since the price is high, it is necessary to find alternative media and spawn substrates using locally available materials. The objective of this study was to produce readily available and reasonably priced an alternative cladode of Opuntia ficus-indica culture medium for the mycelial growth of Pleurotus ostreatus. Thus, three formulated cactus pear cladode agars (CPCAs) with concentrations of 40, 20, and 13.33 g/L and PDA (control) were used. Chemical composition analysis of the CPCA revealed the presence of carbohydrates (39.54 ± 0.09%), crude fiber (26.25 ± 0.35%), ash (5.32 ± 0.11%), crude protein (18.93 ± 0.01%), and moisture (6.09 ± 0.16%). A larger mycelial diameter (7.97 ± 0.21 cm) and growth rate (1.59 ± 0.04 cm/day) occurred on CPCA (40 g/L) at PDA, in which the mycelial growth diameter and growth rate were found to be 6.32 ± 1.03 cm and 1.15 ± 0.01 cm/day, respectively, after 5 days of measurement. A similar mycelial density on CPCA (40 g/L) and PDA media was observed after 8 days of incubation. Similar mycelial growth was observed on sorghum (the control) and sliced dry cladodes of cactus pear (alternative) after 16 days of incubation. Generally, CPCA (40 g/L) can potentially serve as an inexpensive, locally available alternative medium to grow oyster mushrooms.